Final One Thesis
Final One Thesis
TULSI THAPA
JULY 2022
EFFECT OF BIOCHAR AND FYM ON SOIL PROPERTIES AND
CAULIFLOWER YIELD AT DASHRATHPUR, SURKHET, NEPAL
TULSI THAPA
THESIS
SUBMITTED TO THE
AGRICULTURE AND FORESTRY UNIVERSITY
FACULTY OF AGRICULTURE
RAMPUR, CHITWAN
NEPAL
JULY 2022
CERTIFICATE
This is to certify that the thesis entitled " EFFECT OF BIOCHAR AND FYM
ON SOIL PROPERTIES AND CAULIFLOWER YIELD AT DASHRATHPUR,
SURKHET, NEPAL" submitted in partial fulfillment of the requirements for the degree
of Master of Science in Agriculture with major Soil Science of the postgraduate
program, Agriculture and Forestry University, Rampur, is a record of original research
carried out by Mrs. TULSI THAPA, Id. No. SSC-09M-2019, under my supervision, and
no part of the thesis has been submitted for any other degree or diploma.
iii
I would express my deep gratitude and respect to my beloved parents Mr.Janak
Bahadur Thapa and Mrs. Belmati Thapa for their utmost cooperation, sacrifice,inspiration,
heartfelt blessing and encouragement during the entire period of my life. At last, I would
like to express my profound sense of gratitude and cordial indebtedness to my husband
Dipak Rawot, my brother Manoj Thapa and sister Meena Thapa.
Tulsi Thapa
iv
TABLE OF CONTENTS
ACKNOWLEDGEMENT....................................................................................................iii
TABLE OF CONTENTS.......................................................................................................v
LIST OF TABLE..................................................................................................................ix
LIST OF FIGURE.................................................................................................................xi
LIST OF APPENDICES......................................................................................................xii
ABSTRACT.......................................................................................................................xvii
शोध सार................................................................................................................................xix
1. INTRODUCTION..................................................................................................1
1.1. Background 1
1.2. OBJECTIVES 3
2. LITERATURE REVIEW.......................................................................................4
v
3.1. Experimental site 17
3.2. Crop rotation of cropping field 18
3.3. Crop and Variety 18
3.4. Physiochemical properties of soil 18
3.5. Biochar characteristics 18
3.6. FYM characteristics 19
3.7. Experimental setup 19
3.7.1. Treatment description..............................................................................................21
3.8. Agrometeorological features 21
3.9. Cultural operations 21
3.9.1. Land preparation......................................................................................................21
3.9.2. Transplantation........................................................................................................22
3.9.3. Biochar application..................................................................................................22
3.9.4. FYM application......................................................................................................22
3.9.5. Weeding and hoeing................................................................................................22
3.9.6. Harvesting...............................................................................................................22
3.10. Observation and measurement 22
3.10.1. Plant height..............................................................................................................22
3.10.2. Number of leaves per plant......................................................................................22
3.10.3. Canopy width..........................................................................................................23
3.10.4. Curd weight.............................................................................................................23
3.10.5. Curd diameter..........................................................................................................23
3.10.6. Fresh weight of the root, shoot, and biomass...........................................................23
3.10.7. Yield of cauliflower.................................................................................................23
3.11. Soil sampling and preparation 23
3.11.1. Soil analysis.............................................................................................................23
3.12. Plant sampling and preparation 24
3.12.1. Plant tissue analysis.................................................................................................24
3.13. Biochar preparation 24
3.14. Biochar analysis 24
3.15. Farm Yard Manure (FYM) preparation 25
3.16. Farm Yard Manure (FYM) analysis 25
3.17. Statistical analysis 25
4. RESULT...............................................................................................................26
vi
4.1. Effects of biochar application in combination with FYM on yield attributing
characteristics of cauliflower 26
4.1.1. Plant height..............................................................................................................26
4.1.2. Number of leaves per plant......................................................................................27
4.1.3. Canopy width..........................................................................................................28
4.2. Effect of biochar application in combination with FYM on yields of cauliflower.
29
4.2.1. Biomass yield..........................................................................................................29
4.2.2. Shoot yield...............................................................................................................30
4.2.3. Root yield................................................................................................................31
4.2.4. Curd diameter..........................................................................................................31
4.2.5. Curd yield................................................................................................................31
4.3. Effects of biochar application in combination with FYM on soil properties 32
4.3.1. Soil pH.....................................................................................................................32
4.3.2. Soil organic matter...................................................................................................33
4.3.3. Bulk density.............................................................................................................33
4.3.4. Primary nutrient contents in soil..............................................................................33
4.4. Effects of nutrient content on cauliflower plants 35
4.4.1. Nitrogen contents.....................................................................................................35
4.4.2. Phosphorous contents..............................................................................................36
4.4.3. Potassium contents..................................................................................................36
5. DISCUSSION.......................................................................................................37
This research was conducted in single season, further long term research is
necessary in different agro-climatic regions........................................................................43
Research limited in sandy loam texture, can be done in variable soil textures....43
vii
LITERATURE CITED........................................................................................................44
APPENDICES......................................................................................................................59
BIOGRAPHIC SKETCH.....................................................................................................67
viii
LIST OF TABLE
1. Relative proportion range of the four main components of biochar (weight percentage)
as commonly found for a variety of source materials and pyrolysis
conditions……………….7
2. Summary of total elemental composition (C,N, mineral N, C:N, P, available Pand K)
and pH ranges and means of biochar from a variety of feedstocks ( wood, green
wastes, crop residues, sewage sludge, litter, nut shells) and pyrolysis consitions (350-
500 ̊C)...................................................................................................................................8
3. Physico-chemical soil properties of experimental site.....................................................17
4. Chemical properties of biochar........................................................................................18
5. Chemical properties of FYM … ……………………………………………………18
6. Treatment descriptions of the experiment.........................................................................20
7. Analysis methods for various soil properties.....................................................................23
8. Analysis methods for various biochar properties...............................................................24
9. Analysis methods for various FYM properties.................................................................24
10. Effects of different rate of biochar application in combination with FYM on plant
height of cauliflower at Dasrathpur, Surkhet, Nepal, 2021............................................…25
11. Effects of different rate of biochar application in combination with FYM on number
of leaves per plant of cauliflower at Dasrathpur, Surkhet, Nepal, 2021............................27
12. Effects of different rate of biochar application in combination with FYM on canopy
width of cauliflower at Dasrathpur, Surkhet, Nepal, 2021.................................................28
13. Effects of different rate of biochar application in combination with FYM on yield of
cauliflower at Dasrathpur, Surkhet, Nepal, 2021...............................................................29
14. Effects of different rate of biochar application in combination with FYM on curd
diameter and curd yield at Dasrathpur, Surkhet, Nepal, 2021...........................................30
15. Effects of different rate of biochar application in combination with FYM on soil pH,
soil organic matter and soil bulk density at Dasrathpur, Surkhet, Nepal, 2021................31
16. Effects of different rate of biochar application in combination with FYM on total
nitrogen,available phosphorous and available potassium content of soil at cauliflower
harvest at Dasrathpur, Surkhet, Nepal, 2021.....................................................................33
17. Effects of different rate of biochar application in combination with FYM on nitrogen,
phosphorous and potassium content in plant sample of cauliflower at harvest at
Dasrathpur, Surkhet, Nepal, 2021......................................................................................34
ix
x
LIST OF FIGURE
Figure 1 Map of Nepal indicating experimental location at Dasrathpur, Surkhet................17
Figure 2 Layout of experimental field showing treatments and replication.........................19
Figure 3 Weather record during experiment at Surkhet, Nepal (2021/22)...........................20
xi
LIST OF APPENDICES
Appendix 1. Weather record during an experiment at Surkhet ( 2021/22)..........................57
Appendix 2. Analysis of variance table for plant height of cauliflower at 15 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................59
Appendix 3. Analysis of variance table for plant height of cauliflower at 30 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................59
Appendix 4. Analysis of variance table for plant height of cauliflower at 45 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................59
Appendix 5. Analysis of variance table for number of leaves of cauliflower at 15 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................60
Appendix 6. Analysis of variance table for the number of leaves of cauliflower at 30 DAT
as influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................60
Appendix 7. Analysis of variance table for the number of leaves of cauliflower at 45 DAT
as influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................60
Appendix 8. Analysis of variance table for canopy width of cauliflower at 15 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................61
Appendix 9. Analysis of variance table for canopy width of cauliflower at 30 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................61
Appendix 10. Analysis of variance table for canopy width of cauliflower at 45 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................61
Appendix 11. Analysis of variance table for biomass yield of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................57
xii
Appendix 12. Analysis of variance table for shoot weight of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................57
Appendix 13. Analysis of variance table for root weight of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................58
Appendix 14. Analysis of variance table for curd yield of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................58
Appendix 15. Analysis of variance table for curd diameter of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22) 58
Appendix 16. Analysis of variance table for soil pH as influenced by different doses of
biochar application in combination with FYM at Dasrathpur, Surkhet, Nepal (2021/22)...62
Appendix 17. Analysis of variance table for soil organic matter as influenced by different
doses of biochar application in combination with FYM at Dasrathpur, Surkhet, Nepal
(2021/22)..............................................................................................................................62
Appendix 18. Analysis of variance table for soil bulk density as influenced by different
doses of biochar application in combination with FYM at Dasrathpur, Surkhet, Nepal
(2021/22)..............................................................................................................................62
Appendix 19. Analysis of variance table for total nitrogen content of soil as influenced by
different doses of biochar application in combination with FYM at Dasrathpur, Surkhet,
Nepal (2021/22)...................................................................................................................63
Appendix 20. Analysis of variance table for available phosphorous content of soil as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................63
Appendix 21. Analysis of variance table for available potassium content of soil as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................63
Appendix 22. Analysis of variance table for total nitrogen content in plant sample as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................64
xiii
Appendix 23. Analysis of variance table for total phosphorous content in plant sample as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................64
Appendix 24. Analysis of variance table for total potassium content in plant sample as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22).................................................................................64
xiv
ACRONYMS AND ABBREVIATIONS
% Percentage
* Significant at 0.05 Probability level
** Significant at 0.01 Probability level
@ At the rate
̊C Degree centigrade
AFU Agriculture and Forestry University
ANOVA Analysis of Variance
BC Biochar
BD Bulk Density
C Carbon
C/N Carbon Nitrogen Ratio
CEC Cation Exchange Capacity
Co2 Carbondioxide
CH4 Methane
CV Coefficient of variance
DAT Days After Transplanting
DM Dry Matter
DMRT Ducans Multiple Range Test
et al. et alii
FYM Farm Yard Manure
g Gram
ha Hectare
Kg kilogram
LSD Least Significane Difference
mg Milligram
Mg Megagram
mm Millimeter
MoAD Ministry of Agriculture Development
NPK Nitrogen, Phosphorus, Potassium
NS Non significant
OM Organic Matter
pH pussiance de Hydrogen
xv
RCBD Randomized Complete Block Design
SEM Standard Error of Mean
SMC Soil Moisture Content
SOM Soil Organic matter
Temp. Temperature
Yr Year
xvi
ABSTRACT
Name: Tulsi Thapa ID. No.: SSC-09M-2019
Semester and year of admission:First, 2019 Degree: M.Sc.Ag.
Major advisor: Prof. Chandeshwar Prasad Shriwastav Department: Soil Science and
Agri-engineering
A field experiment was conducted to evaluate the effects of biochar applicaton in
combination with FYM on soil properties, yield and yield attributing characteristics of
cauliflower (Brassica oleracea L. var. botrytis) at Bheriganga Municipality, Surkhet
district, Karnali Province Nepal from November, 2021 to Febraury, 2022.The experiment
was laid out in a Randomized Complete Block Design (RCBD) with seven treatments
replicated three times. Snowcrown variety of cauliflower was used as a test crop. Maize
cobs were used to prepare biochar and it was prepared under pyrolytic condition and
applied to the field as per the treatments before transplantation of the cauliflower
seedlings. The application of biochar significantly increased the plant height, canopy
width, biomass yield, shoot yield, root yield, curd diameter and curd yield over control.
The highest biomass yield (33.67 t/ha), shoot yield (30.94 t/ha), root yield (2.74 t/ha), curd
diameter (14.82cm) and curd yield (16.62t/ha) was recorded from 20 Mg ha -1 biochar &12
t/ha FYM application. There was no significant difference from the application of different
rates of biochar in combination with FYM on number of leaves per plant and plant height
at 45 DAT. The soil organic matter, total nitrogen, available phosphorous and available
potassium in soil were significantly higher with addition of biochar along with FYM and
soil bulk density significantly decreased as compared to control. Soil pH remained
unaffected by biochar application along with FYM. The highest content of total N (0.07%),
available P (71. 67Kg/ha) and available K (440.24 Kg/ha) in soil were obtained from 20
Mg ha-1 biochar along with 12 t/ha FYM application. Similarly, highest soil organic matter
(3.29%) was obtained from 20 Mg ha -1 biochar along with12 t/ha FYM application and
lowest bulk density (1.27g/cm3) was obtained from 10 and 20 Mg ha -1 biochar along
with12 t/ha FYM application. The highest content of nitrogen (2.38%), phosphorous
(0.028%) and potassium (0.132%) in plant sample of cauliflower was observed from 20
Mg ha-1 biochar along with 12 t/ha FYM application. Thus it is indicated that the
application of 20 Mg ha-1 biochar along with 12 t/ha FYM would be imperative to increase
xvii
soil fertility and yield of cauliflower but higher rate of biochar than 20 Mg ha -1 is not
recommended to be used as too much use of biochar in soil might cause the problems like
soil alkalinity and nutrient locking being unavailable to the plants and there might not be
optimum utilization of biochar and resources.
xviii
शोध सार
इन्जिनियरिङ्ग
दोमट बलौटे किसिमको माटोमा बायोचारको प्रयोगबाट माटोको गुणहरु र फु लगोभिको उत्पादन तथा
उत्पादनमा असर गर्ने गुणहरुको पहिचान गर्न भेरीगंगा नगरपालिका सुर्खेत नेपालमा सन् २०२१
नोबेम्वर देखि सन् २०२२ फे वर्अरी सम्म एउटा अनुसन्धान गरिएको थियो। यो अनुसन्धान
रेन्डोमाइज्ड कम्प्लिट ब्लक डिजाइनमा सातवटा उपचारहरु तिन पटक दोहर्याएयाको थियो |
स्नोक्राउन जातको फु लगोपि अनुसन्धान बालीको रुपमा प्रयोग गरियको थियो।मकै को कोयाबाट
अक्सिजनको अनुपस्थितिमा बायोचार तयार गरी बेर्ना सार्नु भन्दा अगाडि माटोमा मिलाईयो।
बायोचारको प्रयोग गोठे मल संगै गर्दा बोटको उचाई, क्यनोपी चौडाइ, जरा र काण्डको उत्पादन,
फु लगोपीको उत्पादन अर्थपुर्ण रुपले बढेको पाइयो। जम्मा तौल (३३.६७ टन प्रति हे.), काण्डको
तौल (३ 0.94 टन प्रति हे.), जराको तौल (2.७ 4 टन प्रति हे.), फु लगोपीको ब्यास (14.82 से.मी.) र
फु लगोपी उत्पादन (३३.६७ टन प्रति हे.) सबै भन्दा बढि २० मेगाग्राम प्रति हेक्टर बायोचार साथै १२
टन प्रति हेक्टर गोठे मलको उपचारमा पाईयो।पातको संख्या प्रति बोट र बोटको उचाइ बेर्ना सारेको
४५ दिन पछिमा अर्थपुर्ण परिवर्तन पाईएन। बायोचारको प्रयोग गोठे मल संगैगर्दा माटोका गुणहरु
नाइट्रोजन, फस्फोरस र पोटासको मात्रामा अर्थपुर्ण रुपले बृद्धि भएको पाइयो तर माटोको खुद घनत्व
अर्थपुर्ण रुपले घटेको पाइयो। माटोको पि.एचमा भने अर्थपुर्ण बृद्धि नभएको पाइयो। सबैभन्दा बढि
नाइट्रोजन (0.07%), फस्फोरस (71.67 के जी प्रति हे.) र पोटास (440.24 के जी प्रति हे.) को मात्रा
२० मेगाग्राम प्रति हेक्टर बायोचार साथै १२ टन प्रति हेक्टर गोठे मलको उपचारमा पाईयो।त्यसैगरी
सबैभन्दा बढि प्राङ्गारिक पदार्थ (3.29%) २० मेगाग्राम प्रति हेक्टर बायोचार संगै १२ टन प्रति हेक्टर
xix
गोठे मलको उपचारमा पाईयो भने कम माटोको खुद घनत्व (1.27 ग्राम प्रति घन मिटर) १० र २०
मेगाग्राम प्रति हेक्टर बायोचार संगै १२ टन प्रति हेक्टर गोठे मलको उपचारमा पाईयो। बिरुवामा
सबैभन्दा बढि नाइट्रोजन (2.38%), फस्फोरस (0.028%) र पोटास (0.132%) २० मेगाग्राम प्रति
हेक्टर बायोचार संगै १२ टन प्रति हेक्टर गोठे मलको उपचारमा पाईयो।त्यसैले हाम्रो अध्ययनले २०
मेगाग्राम प्रति हेक्टर बायोचार संगै १२ टन प्रति हेक्टर गोठे मलको उपचारले माटोको उर्वरा शक्ति र
फु लगोपीको उत्पादन बढाउनमा महत्वपूर्ण भुमिका खेल्छ तर २० मेगाग्राम प्रति हेक्टर बायोचार
भन्दा बढि माटोमा प्रयोग गर्न उपयुक्त देखिएन किन भने त्यसले क्षारीयपन बढाउने र पोषक तत्व
बिरुवालाई उपलब्ध हुन नदिने भएकाले हामिले बायोचारको अधिकतम प्रयोग गरि फाइदा लिन
सक्दैनौ।
xx
1. INTRODUCTION
1.1. Background
For sustainable agriculture and food production, the soil is an important resource whereas
the risk of rapid degradation of soil is increasing globally (Symeonakis et al., 2016). The
only solution to achieve food security is the restoration of unproductive soil i.e.
enhancement of soil quality by carbon sequestration in soil (Mekuria et al., 2016; Zhang &
Ok, 2014; Bruun et al., 2015). Some researchers reported the crop response to the applied
fertilizer depended on soil organic matter which is the reason application of chemical
fertilizer alone for achieving higher yield has not been enough for crop production
(Ojeniyi, 2012). Approximately 24% of the global land area have found to be covered by
degraded land and in tropical region soil organic carbon stock (SOC) has declined to 41%
(FAO & ITPS, 2015). Long-term application of chemical fertilizer has lots of negative
impacts on soil such as soil physical quality degradation and also such soil prone to
acidification (Ogbodo, 2013). The smallholder farmers of Nepal are facing serious
problems regarding scarcity and the late distribution of fertilizers (Egwu, 2015). There is a
need for a cheaper & environmentally friendly fertilizer for small and commercial farmers
for sustainable agricultural productivity in the region.
Biochar is a charcoal that is produced under high temperatures i.e. from 300 upto 500°C
through the process of pyrolysis of organic materials in an oxygen-limited atmosphere.
Biochar has properties that are suitable for the safe and long-term storage of carbon in the
environment and also has potential to improve soil which could be prepared by using crop
residues, animal manure, or any type of organic material (Bracmort, 2010). Pyrolysis
could be done through two main methods. One is fast pyrolysis in which heating of
biomass in the absence of oxygen is carried out and yields 60% bio-oil, 20% biochar, and
20% syngas and is also completed in seconds (Chan et al., 2007). Next is slow pyrolysis
which is carried out by natural burning or by the combustion of biomass under oxygen-
limited conditions & is optimized to produce substantially more char ( ∼50%), but takes
hours to complete (Sohi et al.,2009). The use of biochar in fields has the potential to
increase crop yields, decrease soil acidity, increases water and nutrient holding capacity,
stimulates nutrient uptake, and reduce the greenhouse gas emissions from the soil due to
these reasons agricultural use of biochar has been growing and attracting more research
interest globally (Sohi et al., 2009 & Quayle, 2010).
1
Higher content of carbon is present in biochar produced through pyrolysis of biomass
which helps in improvement of environmental quality from the reduction of nutrient
leaching losses, bioavailability of environmental contaminants, sequestering carbon,
reducing greenhouse gas emissions, and enhancing crop productivity in degraded soils
(Ippolito et al., 2012). Various organic materials such as crop residues, forest litters, twigs,
and animal residues could use in the production of biochar. In Nepal, agricultural and
forest wastes are available in higher amount and farmers practice of open burning of these
wastes which resulted in a loss of nutrient resources from the soil. So, using these wastes
in biochar production helps to get potential benefits from crop production, and increase
soil fertility, and carbon sequestration. Also, Nepalese farmers have faced a problem of
the unavailability of quality and sufficient quantity of fertilizers on time which is the main
limiting factor for crop production. The conversion of the agriculture and forest waste into
biochar could be one of the best options to prevent the loss of resources and the use of
biochar as a soil amendment could solve the problem of fertilizer unavailability to the
farmers. Although several pieces of researches have been conducted on the efficiency of
biochar elsewhere in the world there is limited information available in Nepal about the
efficiency of biochar to maintain the productivity of soil and crops.
Cauliflower (Brassica oleracea L. var. botrytis) is one of the most important and profitable
vegetable crops in Nepal. Total cultivated area of cauliflower in Nepal is about 35,402 ha
which is 12% of the total area under vegetable crops and it has the highest share in terms
of production which is 528,738 tons followed by cabbage i.e. 494,053tons (MoAD,
2020). The crop is very responsive to soil nutrients and climatic requirements (Nath &
Singh, 1987). The agro-climatic conditions across the country favor the production of
cauliflower even in the summer season with export potentiality. It is a good source of
protein, thiamin, riboflavin, phosphorus and potassium, dietary fiber, vitamin C, vitamin
K, vitamin B6, folate, pantothenic acid, and manganese (Bhandari & Kwak, 2015). It also
has medicinal values and therapeutic effects as it contains a high concentration of
glucothiocyanate, which is effective in the inhibition of carcinogenesis (McDonald, 1971).
Cauliflower requires a considerable amount of nutrients for growth and development .
Farmyard manure is one of the oldest organic manure used by farmers in growing different
crops due to its easy availability and nutrient content. It is the decomposed dung and urine
along with litter and fodder fed to animals. The application of FYM in the soil helps in
increasing the fertility of the soil as physical condition including its water holding
2
capacity. Nutrient release is very slow but steady and also activates soil microbial biomass
(Ayuso et al., 1996; Belay et al., 2001). Better nutrient recycling and improvement of soil
physical attributes is the positive aspect of organic manures as they could sustain the
cropping system (El-Shakweer et al., 1998).
1.2. OBJECTIVES
GENERAL OBJECTIVE
To evaluate the effects of biochar application incombination with FYM
on cauliflower production and soil properties in Surkhet.
SPECIFIC OBJECTIVES
• To determine the effects of biochar and FYM on soil properties and
nutrient uptake by cauliflower
• To determine the effect of biochar and FYM on yield and yield
attributing characters of cauliflower.
3
2. LITERATURE REVIEW
This chapter deals with the review of various literatures regarding the various aspects of
biochar and their effect on soil properties and crop production.
2.1. Biochar as a soil amendment: an overview
Biochar can be used as a soil amendment to increase plant growth yield, improve water
quality, increase soil moisture retention and availability to plants, reduce soil emissions of
GHGs, reduce leaching of nutrients, reduce soil acidity, and reduce irrigation and fertilizer
requirements. The above-mentioned properties depends on the properties of the biochar
and also based on regional conditions such as soil type, condition (depleted or healthy),
temperature, and humidity. Biochar could also be used in the reclamation of degraded and
spoiled lands i.e. acidic and alkaline soils.There are lots of positive effects on soil’s
physical and chemical properties including nutrient availability,CEC,pH,soil strength, and
moisture holding capacity after the addition of biochar to soil. The properties of biochar
being applied reflect the chemical changes that occurred in soil (Chan et al., 2008).
Increase in total C, total N, pH, CEC, available P, and exchangeable cations such as Ca,
Mg, Na, and K in the soil after biochar application has been reported by many researchers
(Van zwietan et al., 2010).
2.2. Carbon sequestration in soils
Beneficial strategy in mitigation of global warming has proposed application of biochar
due to its positive aspects such as increment in the long-term C sequestration potential and
reduction of greenhouse gases emission (Lehmann and Joseph, 2015; Lehmann and
Rondon, 2006; Spokas et al., 2012b; Woolf et al., 2010; Zhang et al., 2013). The
production of a highly stabilized C by the pyrolysis of biomass helps to explain the C
sequestration potential of biochar which is very slowly decomposed in soil (Sohi et al.,
2009). It has been reported that 50% loss of biomass C in biochar production compared to
biomass inputs in agricultural fields has a considerably higher fraction of the stable C
remains in the soil for longer time periods. Additional benefits of biochar are avoided the
emission of CO2 through the decrease in fertilizer demands to achieve crop yields by
improving soil water and nutrient-retention capacities (Woolf et al., 2010). Reduction in
emissions of CO2 (Lehmann, 2007; Stewart et al., 2013), and biochar soil amendment help
to mitigate the emissions of nitrous oxide (N 2O) (Spokas et al., 2009a) and methane (CH 4)
4
(Leng et al., 2012) from agricultural soils by enhancing soil aeration and decreasing
changes in land use due to optimization of crop yields.
2.3. Pyrolysis and biochar
Biochar which is mainly stable black carbon material is derived from pyrolysis generally
between 300 and 1000°C of biomass under oxygen-limited environments (Jeffery et al.,
2011; Tan et al., 2015). Under oxygen-depleted conditions, the thermal decomposition of
biomass material is pyrolysis (Lehmann & Joseph, 2009). Pyrolysis is generally classified
by the rate of reaction into slow pyrolysis, fast pyrolysis, and flash pyrolysis, (Brewer,
2012; Laird et al., 2009). It can be used to transform organic materials into bio-oil, syngas,
and biochar (Bruun et al., 2012). Mainly two thermal conversion processes are being
highly used in biochar production are slow and fast pyrolysis technology (Woolf et al.,
2010). Slow pyrolysis is mostly used and carried out at very low temperatures and heating
rates and longer residence times compared to fast pyrolysis which optimizes biochar yields
over energy production (Kookana et al., 2011; Yuan et al., 2011).
Thermal conversion of biomass helps to yield biochar with greater C concentration and
along with changes in the nutrient concentration and forms. Ancient Amazonian Darks
Earths in Brazil also known as Terra Preta de Indio (Anthrosols) show high soil organic
matter and high concentrations of exchangeable cations and available phosphorus (Sohi et
al., 2010) which resulted from long-term biochar application. The high concentration of
nutrients and carbon in the charred materials has been found to be responsible for
sustaining long-term C stability (several hundred to several thousand years) and
enhancingthe high level of fertility of these soils (Glaser et al., 2001). The resultant
materials from biomass pyrolysis are more chemical recalcitrant and resistant to biological
decomposition than native organic matter, increasing stable soil organic C pools which can
be used as a long-term carbon sequestration alternative (Alburquerque et al., 2014;
Lehmann & Rondon, 2006). Biochar has a biphasic character, with both labile and stable
carbon pools whose ratios dictate by the proportions of hemicellulose, cellulose, and lignin
content of the feedstock (Joseph et al., 2013; Sohi et al., 2009). High pyrolysis temperature
leads to an increment in aromaticity i.e. nonvolatile, high C, and low O material of biochar.
These chars are oxidized haltingly and form surficial, oxygen-containing functional groups
(Jung et al., 2016). Contrarily, biochars formed at lower temperatures contain more labile,
volatile components of relatively low C and high oxygen content (aliphatic) (Fang et al.,
2014; Novak et al., 2010; Zimmerman, 2010). The elements found in biochar are carbon
5
with concentrations varies between 172g kg –1 and 905g kg–1; nitrogen concentrations from
1.8g kg–1 to 56.4g kg–1 have been reported, and total phosphorous from 2.7g kg –1 to 480g
kg–1, and total potassium from 1.0g kg–1 to 58g kg–1 (Chan & Xu, 2009; Lehmann &
Joseph, 2009). Biochar also consists of other elements such as oxygen, hydrogen, sulfur,
base cations, and heavy metals to varying extents (Preston &Schmidt, 2006). This
variableness in nutrient properties can be allocated to biochar feedstocks and pyrolysis
conditions (Lehmann & Joseph, 2009). Biochar C/N ratios vary from 7 to 400, with greater
C/N ratios observed at high temperatures affecting the slow mineralization of biochar due
to the presence of aromaticity during thermochemical conversion (Yuan et al., 2011) The
pH of the resulting biochars can vary from 4 to 12 (Lehmann & Joseph, 2009) with a
gentle increase in pH values with higher pyrolysis temperatures (Naeem et al., 2016). The
high pH values of biochar can be known by the concentration of alkaline elements at high
temperatures (Chen et al., 2014; Mukherjee et al., 2011). In addition, high pyrolysis
temperature has been found to increase biochar ash content (Gunes et al., 2015) while it
reduces volatile compounds i.e. C, H, and O (Purakayastha et al., 2016), and cation
exchange capacity of biochar (Song & Guo, 2012). The latter becomes higher with time
upon incorporation into the soil, exposition to O 2 and water, and the presence of abiotic
and biotic oxidation of functional group on biochar particles (Cheng et al., 2008; Liang et
al., 2006). As a tool for soil remediation, high pyrolysis temperature has been known to
produce effective biochar for environmental contaminant sorption (Fryda & Visser, 2015;
Liu et al., 2012; Xie et al., 2015) as specific surface area, microporosity, and surface
hydrophobicity increase with higher pyrolysis temperature (Ahmad et al., 2014). However,
the effectiveness of each type of biochar for soil amendment is highly influenced by its
physical and chemical nature, and economic, logistical, and environmental factors (Gomez
et al., 2014; Novak et al., 2010).
2.4. Structural and chemical composition of biochar
2.4.1. Structural composition
A considerable amount of mass loss is observed from the thermal degradation of cellulose
between 250ºC and 350ºC in the form of volatiles leaving behind a rigid amorphous C
matrix. With the increment in pyrolysis temperature, the proportion of aromatic carbon in
the biochar also increases, due to the relative increase in the loss of volatile matter i.e.
initially water, followed by hydrocarbons, tarry vapors, H 2, CO, and CO2, and the
transformation of alkyl and O-alkyl C to aryl C (Baldock & Smernik, 2002; Demirbas,
6
2004). Around 330ºC, polyaromatic graphene sheets begin to grow laterally at the expense
of the amorphous C phase and eventually coalesce. Above 600ºC, carbonization becomes
the dominant process. Carbonization is distincted by the removal of most remaining non-C
atoms and resulted in a relative increase of the C content, that can be up to 90% (by
weight) in biochars from woody feedstocks (Antal & Gronli, 2003; Demirbas, 2004). It is
commonly accepted that each biochar particle consists of two main structural fractions:
stacked crystalline graphene sheets and randomly ordered amorphous aromatic structures.
Hydrogen, O, N, P, and S are found predominantly incorporated within the aromatic rings
as heteroatoms (Bourke et al., 2007). The presence of heteroatoms is found to be a great
contribution to the greatly heterogeneous surface chemistry and reactivity of biochar.
2.4.2. Chemical composition and surface chemistry
Biochar composition is highly heterogeneous and contains both stable and labile
components (Sohi et al., 2009). Carbon, volatile matter, mineral matter (ash), and moisture
are generally considered as its major components (Antal & Gronli, 2003). Their relative
proportion values in biochar as commonly found for a variety of source materials and
pyrolysis conditions are given in the below table (Antal & Gronli, 2003; Brown, 2009).
Table 1.Relative proportion range of the four main components of biochar. Weight
percentage is commonly found for a variety of source materials and pyrolysis conditions
Component Proportion(ww-1)
Fixed carbon 50-90
Volatile matter (e.g tars) 0-40
Moisture 1-15
Ash (mineral matter) 0.5-5
The relative proportion of biochar components dictates the chemical and physical behavior
and also a function of biochar as a whole (Brown, 2009), which in turn regulates its
suitability for a site-specific application, transport, and fate in the environment (Downie et
al., 2009). Moisture is another critical component of biochar (Antal & Gronli, 2003) and
higher moisture contents lifts up the costs of biochar production and transportation for a
unit of biochar produced. Maintaining the moisture content upto 10% (by weight) appears
to be desirable. In order to achieve this pre-drying, the biomass feedstock may be very
important in biochar production. Biochar could be produced from a wide range of
feedstocks under different pyrolysis conditions whose high carbon content and strongly
7
aromatic structure are constant features (Sohi et al., 2009). According to Sohi et al.,
(2009), these features largely account for its chemical stability. Similarly, pH shows less
variableness between biochars and is typical>7.
Table 2. Summary of total elemental composition (C, N, C:N, P, K, available P, and
mineral N) and pH ranges and means of biochars from a variety of feedstocks (wood,
green wastes, crop residues, sewage sludge, litter, nut shells) and pyrolysis conditions
(350ºC-500ºC) used in various studies (Chan & Xu, 2009).
pH C N N C:N P Pa
K
(g kg -1) (g kg-1) (No3-+NH4+) (g kg-1) (g kg-1)
(g kg-1)
(mg kg-1)
Range From: 6.2 172 1.7 0.0 7 0.2 0.015
1
To: 9.6 905 78.2 2.0 500 73 11.6
58
Mean 8.1 543 22.3 61 23.7
24.3
(Source: Chan & Xu, 2009)
Total carbon content in biochar was found to have a value between 172 to 905 g kg -1,
although OC often accounts for < 500 g kg -1 for different source materials (Chan & Xu,
2009). Total N ranged between 1.8 and 56.4 g kg-1, depending on the feedstock (Chan &
Xu, 2009). Biochar total N content may not be necessarily useful to crops because N is
mostly found in an unavailable form i.e. mineral N contents < 2 mg k -1 (Chan & Xu, 2009).
Nuclear magnetic resonance (NMR) spectroscopy has revealed that aromatic and
heterocyclic N-containing structures in biochar occur as a result of biomass heating,
converting labile structures into more recalcitrant forms (Almendros et al., 2003). C:N
(carbon to nitrogen) ratio in biochar has been known to differ widely between 7 and 500
(Chan & Xu, 2009), with implications for nutrient retention in soils. C:N ratio has been
generally used as an indicator of the capacity of organic substrates to release inorganic N
when incorporated into soils. Total P and total K in biochar were observed to range widely
according to feedstock between 2.7 - 480 and 1.0 - 58.0 g kg -1, respectively (Chan & Xu,
2009). Total N, P, and K content in biochar has a wider range than those reported in the
8
literature for typical organic fertilizers. Most minerals within the ash fraction of biochar
are observed to occur as discrete associations independent of the carbon matrix, with the
exception of K and Ca (Amonette & Joseph, 2009). Generally, each mineral association
consists of more than one type of mineral. Joseph et al., (2009) highlighted that our current
understanding of the role of high-mineral ash biochars is still limited, as we face the lack
of available data on their effect on soil properties at long-term basis. The review of related
literature has revealed that the full knowledge of the composition of biochar as a soil
amendment, the way it is influenced by those parameters, and also the implications for soil
functioning, is still scarce. Partly, this can be interpreted by the fact that most
characterization work has involved charcoals with high carbon and low ash content, as
required by the increasingly demanding market for activated carbon. Likewise, the next
factor is the broad variety of processing conditions and feedstocks available. Nevertheless,
the current disaggregation of biochar standards is greatly reflected in the poor
understanding of the link between biochar composition, its behavior, and function in soil.
2.5. Effects of biochar on physical properties of soil
It has been reported that biochar has a relatively greater surface area which affects biochar
interactions with soil solution substances as well as evokes a net increase in the total soil-
specific surface of biochar-amended soils (Lehmann et al., 2009). Depending on feedstock
biomass and process conditions, the bulk density of biochar ranges from 0.08 g cm −3
(Gundale & DeLuca, 2006) to 0.43 g cm−3 (Pastor-Villegas et al., 2006) which is lower
than that of mineral soil ranging from 1.16 to 2.00 g cm −3 (Chaudhari et al., 2013). Hence,
depletion in soil bulk density is observed due to biochar’s low bulk density and its highly
porous structure (Laird et al., 2010; Sun et al., 2013b; Downie et al., 2009). As production
processes induce loss of volatile matter results in a highly porous structure that is why
biochar not only improves soil water movement but also soil water retention characteristics
(Lim et al., 2016; Novak et al., 2012; Asai et al., 2009; Karhu et al., 2011; Ogawa et al.,
2006). Prominent differences in water retention with 18% increment in terra preta
compared to adjacent soils due to higher biochar concentrations and higher levels of
organic matter have been reported (Glaser et al., 2002). An increase in available moisture
for coarse texture and low organic matter content sandy soil in biochar amended soil has
also been reported so far whereas just marginal to moderate enhancement has been
observed in medium textured soils and a decrease in moisture retention for clayey soils
also observed (Liu et al., 2012; Laird et al., 2010; Sohi et al., 2010). For clayey soils,
9
biochar application has positive impacts such as enhancement in aggregate stability and
changes in water retention (Soinne et al., 2014).
10
increase in macropores, and turn to increased water content at low suction pressures.
Biochar’s interaction with organic particles or parent soil mineralsresults in changes in soil
porosity (Lehmann et al., 2011). Reduction in soil bulk density and increment in total soil
porosity is due to biochar exhibiting low density (300 kg m-3 ) and highly stable organic
carbon (Gwenzi et al., 2015). The application of biochar reduces soil bulk density which in
turn has a positive effect on root development and growth (Atkinson et al., 2010; Laird et
al., 2010). In contrast, Alameda & Villar, (2012) reported that greater soil bulk density
may have a negative influence on plant growth. Biochar application has no significant
changes on soil properties in short term but in the long term soil quality is positively
influenced by aging (Cheng & Lehmann, 2009; Hale et al., 2011; Lin et al.,2012;
Mukherjee et al., 2014). Enhancement of soil aggregation and aggregate stability could be
achieved from the organic carbon present in biochar and also due to changes in soil
structure has positive impacts such as improvement in soil moisture retention, infiltration,
and reduction in runoff and erosion (Gwenzi et al., 2015). The effect of biochar on soil
aggregation is also connected to its surface charge characteristics (Cheng et al., 2006).
2.5.3. Water holding capacity of soil
Connectivity and distribution of pores in soil matrix are influenced by soil texture,
aggregation, and soil organic matter (SOM) which helps in the estimation of soil water
retention (Brady & Weil, 2004; Verheijen et al., 2010; Major, 2009; Sohi et al., 2009). As
compared to other types of SOM, biochar has a greater surface area and porosity which is
best suited for improvement of water retention due to soil texture and soil aggregation
improvement (Verheijen et al., 2010). An effect on soil water retention has been observed
due to an increase in SOM resulting after biochar treatment (Glaser et al., 2002; Major,
2009; Sohi et al., 2009).Soils with low or no charcoal contents were observed to have 18%
lower soil water retention than terra Prete soil which may result due to effects of charcoal
itself and resulting in higher levels of SOM (Glaser, 2002). Feedstock source and
processing condition are the other factors on which soil water characteristics are dependent
and there are lots of findings in the literature. According to Novak et al., (2009) and Chan
et al., (2008) application of biochar resulted in no significant effect on water holding
capacity whereas Novak et al., (2009) observed differences in the water holding capacity
among different soil depending on the type of applied biochar. Application of biochar
exposed to higher pyrolysis temperature has resulted in enhanced water retention capacity
(Lei &Zhang, 2013 & Novak et al., 2009). Water retention curves express soil moisture
11
content at different water tensions and the pF-value is the logarithm of water tension: pF =
log ψm. The permanent wilting point (PWP) is a point at which plants irreversible wilt (pF
= 4.2) whereas field capacity is the water content that soil in undisturbed conditions could
hold water against gravity. Enhancement in soil field capacity was observed when biochar
was applied at higher rates which showed an increase in plant growth and improvement in
water economy (Alburquerque et al., 2014). The initial water content of the soil is also
determined by soil texture so, after biochar application, soil texture influences its actual
effect on water content. According to Lei & Zhang, (2013), biochar produced at higher
temperatures when applied to soil showed a significant increase in plant available water
and macropores in the soil as compared to control. An increase in drought tolerance and
water use efficiency is also found in soil amended with biochar (Kammann et al., 2011).
2.6. Effects of biochar on chemical properties of soil
According to Lehmann and Joseph, (2015) an effective and unique opportunity for
improvement of soil fertility and increment in nutrient use efficiency is possible with the
application of biochar to agricultural soil. Biochar application will enhance soil fertility
and plant growth came after the sustainable fertility of the Terra Preta soil found in central
Amazonia as it consists of high contents of black carbon (Glaser et al., 2002; Lehmann &
Joseph, 2015). Biochar application has a positive effect on soil chemical properties such as
an increase in soil ph, cation exchange capacity (CEC), and nutrient content (Cheng et al.,
2008; Liang et al., 2006). Biochar application has lots of positive impacts such as the
increase in soil pH by decreasing the amount of exchangeable Al 3+ also reducing the
mobility of toxic elements in acid soils as well as improvingK and P availability ( Major et
al., 2010; Yamato et al., 2006; Jeffery et al., 2011). Reduction in the lime application and
increment of crop production in highly weathered infertile tropical soil is also observed
after biochar application (Liu et al., 2012). Due to oxidation of biochar surface and the
presence of abundant negatively charged surface functional groups leads to an increase in
CEC after biochar application in agricultural soils (Cheng et al., 2008). The presence of
greater surface area, porous structure, and negative surface charge in biochar lead to an
increase in CEC of the soil and also increase nutrient retention (Laird et al., 2010). Biochar
addition to soil increases nutrient use efficiency which in turn decreases crop fertilizer
requirement addition (Lehmann & Joseph, 2009; Lehmann & Joseph, 2015; Zheng et al.,
2013). Reductionin the availability of heavy metals and organic pollutants such as dioxins,
12
pesticides, etcis also observed after biochar application due to its large surface area and
high adsorption capacity (Komnitsas et al., 2015; Tang et al., 2013).
2.6.1. Nutrient content
N, P, and basic cations like Ca, Mg, and K are usually present in biochar (Major et al.,
2010). As compared to biochar based on manure, biochar prepared from plant materials
have a lower concentration of nutrients and minerals such as N and P but has a higher C
content (Lehmann et al., 2003; Chan et al.,2008; Waters et al., 2011). With the increasing
pyrolysis temperature C and N concentration also increases for plant-based biochar
whereas for biochar prepared on mineral-rich feedstock such as manure decreases with
increasing pyrolysis temperature as less volatile elements such as P, K, Ca and Mg
concentrate as volatiles fade (Gaskin et al., 2008; Singh et al., 2010). According to the
Gaskin et al.,(2008) showed that poultry litter-based biochar produced at a higher pyrolysis
temperature (500°C) had lower N and greater P, K, and Ca concentration as compared to
that produced at a lower pyrolysis temperature (400°C). But vaporization of P and K
during pyrolysis at temperatures of 700 to 800°C is also observed. Hence, high pyrolysis
temperature leads to nutrient loss through volatilization (Lehmann & Joseph, 2009). The
feedstock used and pyrolysis conditions are two factors on which the actual nutrient
content of biochar and its bioavailability greatly depends and also information regarding
the bioavailability of nutrients contained in biochar is scarce (Gaskin et al., 2008; Singh et
al., 2010)
2.6.2. CEC
The capacity of a material to bind positively charged ions or molecules on negatively
charged surface materials such as clay and soil organic matter is termed CEC(Brady &
Weil, 2008). In other words, CEC is defined as the total amount of exchangeable cations
that are bound to soil. CEC is also expressed as molar equivalents of negative surface
charge per weight of soil (Manahan, 2011). The level of minerals present in the feedstocks
and pyrolysis temperature at the time of production is the factor on which the CEC of
biochar is based (Gaskin et al., 2008; Novak et al., 2009; Nguyen et al., 2010; Singh et al,
2010). Gaskin et al., (2008) and Singh et al., (2010) reported both increments in pyrolysis
temperature resulted ina decrease in CEC and also an increase in CEC with increasing
pyrolysis temperature whereas in general increased CEC was observed from the biochar
produced by slow pyrolysis because of the presence of a higher degree of oxygen surface
functional groups. CEC of biochar is increased slowly when incorporated into soil because
13
of oxidation which occurs due to reactions of water, O2, and several soil agents (Cheng et
al., 2006). CEC of biochar ranges from negligible to 40 cmol g -1 (Verheijen et al., 2010).
Lowe CEC was observed in biochar prepared from plant feedstock compared to the
biochar produced from animal-derived feedstock (Scott et al., 2014).
2.6.3. pH of soil
Biochar prepared from different materials shows pH values from neutral to alkaline so they
are suitable for neutralization of acidic soils (Yamato et al., 2006; Gwenzi et al., 2015;
Novak et al., 2009). According to Chan and Xu (2009), the pH of biochar could also differ
from slightly acidic to alkaline. Depending on the feedstock used and pyrolysis condition
pH value of biochar differ from 4 to 12 (Lehmann, 2007). According to Singh et al.,
(2010), with an increment of pyrolysis temperature, the pH value and CaCo 3 equivalence
of biochar also increase. Increment in the pH value of biochar occurs over time because of
surface oxidation in soil (Cheng et al., 2008). Biochar could act as liming agent by
increasing the pH of the soil which in turn increases nutrient availability and also enhance
nutrient uptake by plants for various soil types (Glaser et al., 2002; Lehmann & Rondon,
2006; Lehmann & Joseph, 2009). Liming potential of biochar is controlled by the
feedstock used and pyrolysis condition and also estimates ash and carbonates content
(Singh et al., 2010; Berek, 2014). As compared to biochar prepared from wood or
greenwaste higher neutralizing capacity has been found in biochar based on feedstocks
richer in ash such as animal manure (Kookana et al., 2011).
2.7. Effects of biochar on plant yield
For many crops and plants grown in a different environment with the application of
biochar to soil has resulted in significant crop yield benefits (Lehmann & Joseph, 2015).
Application of biochar in combination with fertilizer in the area of Amazon concluded to
have sustained crop yield which was the result of improvement in various soil properties
(Lehmann et al., 2003). An increase in maize, cowpea, and peanut yield was observed in
biochar amended soil which was due to improvement in soil properties such as increment
in soil pH, CEC, nutrient availability, and decrease in exchangeable Al 3+ content (Yamato
et al., 2006). After application of 15 and 20 t/ha biochar 150% and 98% increase in yield
of maize grain was observed along with improvement in soil’s physical and chemical
properties (Uzoma et al., 2011). Not only beneficial effect but detrimental effect of biochar
on plant productivity has also been reported in peat soil and also moderate to a negative
effect of biochar amendment in grain production was also observed in most of the leading
14
countries (Crane-Droesch et al., 2013). After biochar application,an almost 68% reduction
in the yield of mustard and barley was observed because of an increase in Mo
micronutrient and a decrease in Cu,Fe,Mn, and Zn in plant tissues (Kloss et al., 2014).
Steiner et al., (2007) and Widowati et al., (2011) investigated that increase in yield was due
to the lower nitrogen losses from mineral fertilizer under biochar application that also
enhanced soil CEC or due to the inhibition of N-NH 4 to N-NO3from mineral N fertilizer.
Application of biochar @ 2 t/ha along with mineral fertilizer at recommended dose
increased the curd yield of cauliflower by 37 % compared to that of only mineral fertilizer
application and by 59 % compared to that of the control treatment (Timilsina et al.,2020).
2.8. Effect of biochar on plant characteristics
The positive effects of biochar application on plant growth - for example, due to retention
of nutrients - are strongest when combined with organic or inorganic fertilizers, especially
on tropical soils (Alburquerque et al., 2013; Van Zwieten et al., 2010). Peng et al. (2011)
found an increase in maize biomass by 64% (without NPK fertilizer) and an increase of
maize biomass by 146% (with NPK fertilizer) for a Ultisol following biochar application
(2.4 t/ha ). Just a few studies have performed a complete elemental analysis of the plant
biomass which was grown on biochar amended soil (Chan et al.,2008; Van Zwietan et
al.,2010). Van Zwieten et al., (2010) reported that the application of the ash content
biochar did not have a significant effect on N concentration in plant biomass. Biochar
which had higher ash content leads to a relatively higher increase in sunflower growth due
to increased plant availability of nutrients (Alburquerque et al., 2013). The addition of
biochar has been found to directly reduce certain soil constraints and may also have
possibilities to increase crop productivity. It could be illustrated with an example i.e. the
use of biochar with high mineral content is advisable for soils dependent on high nutrient
inputs or soils showing low physical fertility (Slavich et al., 2013). The positive effects of
biochar application on plant growth due to retention of nutrients are strongest when
combined with organic or inorganic fertilizers, especially on tropical soils (Alburquerque
et al., 2013; Hossain et al., 2010; Van Zwieten et al., 2010; Ogawa et al., 2006). Glaser et
al., (2001) and Ogawa et al. (2006) have reported that the addition of low amounts of
biochar (0.5 t ha-1 ) had noticeable effects on various plant species whereas higher doses
of biochar appeared to limit plant growth. Peng et al., (2011) reported an increase in maize
biomass by 64% (without NPK fertilizer) and an increase of maize biomass by 146% (with
NPK fertilizer) for a Ultisol following biochar application (2.4 t ha-1 ). Torres (2011)
15
observed that biochar based on nutrient-poor maize cobs had significant effects on crop
growth, whereas biochar based on a nutrient-rich feedstock did not. Kimetu et al., (2008)
reported a doubled maize yield compared to control on a degraded heavy (45-49% clay)
and light (11-14% clay) Ultisol amended with wood biochar during a field study in West
Kenya.
2.9. FYM
Farmyard manure is the most commonly used organic manure in Nepal for
which the traditional method of preparing and storing FYM is generally faulty.
First cattle dung with stable waste and house sweepings is heaped loosely. Then,
loose heaps are left exposed to the sun and the raw organic matter dries up while it
rains, it gets drenched and all the soluble nutrients get leached from the manure.
Also at the time of organic matter decomposition, the ammonia escapes into the
atmosphere. Reduction in the nutrient content of FYM is due to the wastage of
nitrogen-rich urine, the loss of nitrogen due to fermentation of exposed cattle dung,
washing away of soluble mineral elements by leaching, etc. Sittirungsum et al.
(2001) conducted an experiment in 1998 at Hokkaido in Japan to study the
influence of farmyard manure on the yield and quality of Pak-choi (Brassica
chinensis) and Japanese radish (Raphanus sativus) grown without the application of
chemical pesticides. The yields of pakchoi were highest in control plots cultivated
with standard chemical fertilizers (360.5 g/plant) followed by plots treated with 5 t
farmyard manure (342.0).
Sharma et al. (1979) indicated that in potato crops continuous application of farmyard
manure produced a higher yield than the combined application of P and K as inorganic
fertilizers. Sharma et al. (1980) observed that there is a significant and positive effect of
FYM in summer corp. Grewal & Trehan (1984) showed that the application of FYM in
potato crops at 75 and30 tonnes per ha increased the tuber yield by 39 and 40 percent.
Chavan et al. (1997) found that the combined application of nitrogen through FYM and
urea was more beneficial compared to fertilizer alone in order to increase the yield and
quality of chili. Shanmugasundaram & Savithri (2004) noticed that application of nitrogen
at 120 kg per ha with FYM (10 t/ha) and MgSO4 (2% as a foliar spray) recorded a higher
amount of nitrogen content and uptake of nitrogen in foliage as well as in carrot root. The
FYM on an average contains 1.5% N, 1.0% P205 and 1.5% K2O (Akhtar & Mahmood,
1996). The half dose of Organic manure (750 kg/ha) and half dose of farm yard manure
(FYM) (20 t/ha) application produced the highest curd yield (1019 g) and biomass (2046
g) when the experiment was conducted in the research field of Agriculture Research
16
Station at Belachapi, Dhanusha, Nepal from November 2017 to February 2018 (Devkota et
al., 2022)
17
3.2. Crop rotation of cropping field
The experimental field was under cucumber cultivation before the experiment.
3.3. Crop and Variety
A snowcrown variety of cauliflower was used as a test crop to experiment. It matures in
70 days after showing and is recommended for Terai and Hills.
3.4. Physiochemical properties of soil
Composite soil samples of tillage layers upto 15 cm in the depth of experimental plots
were analyzed to determine the pH, texture, N, P, K, and organic matter content of the soil
before the biochar application. The physicochemical properties of the soil before the
experiment were presented in Table 3.
Table 3. Physicochemical properties of soil
Parameters Value
pH 6.9
Texture sandy loam
Organic matter (%) 1.8
Nitrogen (%) 0.04
Available phosphorous (kg/ha) 43
Available potassium (kg/ha) 188.16
18
3.6. FYM characteristics
The chemical properties of FYM were before its application in the field. The selected
properties of FYM are presented in Table 4.
Table 5. Chemical properties of FYM
Parameters Value
pH 7.8
Total nitrogen (%) 0.81
Total phosphorous (%) 2.08
Total potassium (%) 0.52
19
Replication I Replication II Replication III
1m
T1 2.7m T6 T3
1m
2.4m
T2 T5 T4
T3 T1 T2
T4 T3 T5
T5 T4 T6
T6 T2 T1
T7 T7 T7
20
3.7.1. Treatment description
The treatment descriptions are presented in the table below.
Table 5. Treatment descriptions of the experiment
S.N Treatments Treatment symbol
1 Control T1
2 Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha T2
3 Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha T3
4 Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha T4
5 Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha T5
6 Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha T6
7 Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha T7
3.8. Agrometeorological features
The average data on weather parameters such as total rainfall, maximum and minimum
temperature were recorded at the meteorological station of Kohalpur.
30
25
20
15
10
21
weeds, stubbles, and other unwanted materials were removed manually from the
experimental plots. Twenty-one plots were well prepared according to the experimental
design adopted and they were leveled uniformly.
3.9.2. Transplantation
Cauliflower seedlings were sown in all plots at 60x45 cm plant to plant and row to row
spacing on 25 November 2021. There were altogether 6 rows with one seedling in each
row consisting of 24 plants in each plot.
3.9.3. Biochar application
The well-ground biochar passed through a 1mm sieve was applied in the plots before
two weeks of seedling transplantation.
3.9.4. FYM application
The well-decomposed farm yard manure was also applied to the plots before two weeks of
seedling transplantation.
3.9.5. Weeding and hoeing
The first manual weeding was done at 15 days and the second weeding was done at 30
days after transplanting was to make the soil well pulverized for better aeration and water
holding capacity.
3.9.6. Harvesting
The curds of cauliflower plants were ready for harvesting after almost 3 months of
transplantation. All the sample plants were harvested manually at a time. Harvested plants
from each plot were separated into roots and shoots and they were weighed separately.
3.10. Observation and measurement
The five plants among 24 plants were tagged for data collection leaving 19 plants
from all sides of the experimental unit. The bio-morphological characters of 5 tagged
plants were recorded at the different specified periods.
3.10.1. Plant height
The plant height was measured on 15, 30, and 45 DAT using a measuring scale. It was
measured from the base of the shoot to the apex of the longest leaf.
3.10.2. Number of leaves per plant
The total number of fresh leaves attached to the plant at the time of data collection was
taken from sample plants and an average number of leaves per plant was calculated. Dried
and senescing leaves were excluded from counting in each observation.
22
3.10.3. Canopy width
The canopy width of sample plants was measured using a measuring scale at the time of
data collection.
3.10.4. Curd weight
The weight of the curd of sample plants at harvest was measured using digital balance
and the average was calculated.
3.10.5. Curd diameter
The diameter of the curd of sample plants at harvest was measured using a
measuring scale. Two diameters were measured diagonally and then the average was
calculated.
3.10.6. Fresh weight of the root, shoot, and biomass
With the help of digital balance, the fresh weight of the root, shoot, and whole biomass
was recorded at the time of harvesting.
3.10.7. Yield of cauliflower
Biomass, root, and shoot yields were calculated into tons per hectare (t ha -1) from
the weight of biomass, root, and shoot recorded from the net harvesting area.
3.11. Soil sampling and preparation
The soil was sampled before transplanting and after harvest. Soil samples were collected at
random points in the middle of each plot (to avoid edge effect) from topsoil (0 to 20 cm
depth) with the help of a spade. Samples were grounded in mortar and pestle and passed
through a sieve after air drying at room temperature.
3.11.1. Soil analysis
The properties of the soil before and after the experiment were analyzed at the soil science
laboratory of AFU by the following methods.
23
Table 7. Analysis methods for various soil parameters
Parameters Analysis methods
Soil texture Hydrometer method
Soil pH 1:2 soil water ratio (Black et al., 1965)
24
Table 8. Analysis methods for various biochar properties
Parameters Analysis methods
pH Electrometric method
Total Nitrogen Kjeldahl distillation
Organic matter Chromic acid titration method
Total P Spectrophotometer
Total potassium Flame Photometer
25
4. RESULT
The treatment effects of biochar application, obtained during the course of
investigation are presented in this section
4.1. Effects of biochar application in combination with FYM on yield attributing
characteristics of cauliflower
4.1.1. Plant height
The effect of biochar application on the plant height of cauliflower is presented in Table
12. With the application of biochar in the combination of FYM, the plant height of
cauliflower significantly increased at 15 DAT and 30 DAT but there was a non-significant
difference in height at 45 DAT. At 15 DAT, the tallest plant (12.81 cm) was recorded from
20 Mg ha-1 biochar &12 t/ha FYM application, and the shortest (9.96 cm) from control.
Similarly, at 30 DAT, the tallest (20.65 cm) and shortest (12.92 cm) were recorded from 20
Mg ha-1 biochar &12 t/ha FYM application and control. Likewise, at 45 DAT, the tallest
(30.10 cm) and shortest (22.32 cm) were recorded from 20 Mg ha -1 biochar &12 t/ha FYM
application and control respectively.
26
Table 10.Effects of biochar application on plant height of cauliflower at Dasrathpur,
Surkhet, Nepal.
Treatment Plant height (cm)
15 DAT 30 DAT 45 DAT
Control 9.96 b 12.92b 22.32
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 12.77 a 17.01ab 27.62
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 12.08a 17.04ab 26.22
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 12.40 a 16.97ab 29.26
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 11.45ab 18.74a 26.16
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 12.81a 20.65a 30.10
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 11.36ab 17.32a 22.96
SEM(±) 0.080 0.18 0.37
LSD(α=0.05) 1.74 4.01 7.91
CV 8.27 13.10 16.87
Grand mean 11.83 17.23 26.38
Means followed by the same letter (s) in a column are not significantly different at5% level
of significance as determined by DMRT
27
Table 11.Effects of biochar application on the number of leaves per plant of cauliflower at
harvest at Dasrathpur, Surkhet, Nepal.
Treatment Number of leaves per plant
15 DAT 30 DAT 45 DAT
Control 5.85 7.53 9.00
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 6.60 8.07 9.40
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 6.60 8.00 9.40
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 6.80 8.27 9.53
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 6.67 8.10 9.40
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 7.067 8.47 10.07
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 6.60 8.07 9.47
SEM(±) 0.034 0.024 0.026
LSD(α=0.05) 0.73 0.52 0.57
CV 6.18 3.62 3.37
Grand mean 6.60 8.07 9.47
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
28
Table 12.Effects of biochar application on canopy width of cauliflower at Dasrathpur,
Surkhet, Nepal.
Treatment Canopy width (cm)
15 DAT 30 DAT 45 DAT
Control 12.87c 19.68 b 30.13b
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 14.55bc 28.42a 42.31a
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 15.80ab 28.36 a 41.18a
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 16.10ab 29.86a 44.10a
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 14.28bc 29.80a 46.72a
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 17.76a 31.37 a 47.71a
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 16.25ab 21.34 b 31.22b
SEM(±) 0.099 0.24 0.43
LSD(α=0.05) 2.15 5.32 9.31
CV 7.86 11.09 12.92
Grand mean 15.37 26.97 40.48
Means followed by the same letter (s) in a column are not significantly different at5% level
of significance as determined by DMRT
4.2. Effect of biochar application in combination with FYM on yields of
cauliflower.
4.2.1. Biomass yield
The effect of biochar application on the biomass yield of cauliflower is presented in
Table10. The biomass yield of cauliflower was found higher after the application of
biochar along with FYM as compared to control. The highest biomass yield (33.67 t/ha)
was obtained from 20 Mg ha -1 biochar & 12 t/ha FYM application which was similar to 15
Mg ha-1 biochar application but significantly higher than other treatments. Treatment
receiving no biochar and FYM gave the lowest biomass yield (11.35 t/ha) which was
significantly lower than other treatments.
29
Table 13.Effects of biochar application in combination with FYM on yield of cauliflower
at harvest at Dasrathpur, Surkhet, Nepal.
Treatment Biomass Shoot weight Root weight
(t/ha) (t/ha) (t/ha)
Control 11.35 c 10.28c 1.07d
Biochar @ 0 Mg ha-1 + FYM @ 12 24.88 b 22.50b 2.19bc
t/ha
Biochar @ 5 Mg ha-1 + FYM @ 12 25.34 b 23.45 b 1.88c
t/ha
Biochar @ 10 Mg ha-1 + FYM @ 25.42 b 23.23b 2.18bc
12 t/ha
Biochar @ 15 Mg ha-1 + FYM @ 29.31 ab 27.12ab 2.38ab
12 t/ha
Biochar @ 20 Mg ha-1 + FYM @ 33.67a 30.94a 2.74a
12 t/ha
Biochar @ 25 Mg ha-1 + FYM @ 12.49 c 11.34 c 1.15d
12 t/ha
SEM(±) 0.23 0.21 0.019
LSD(α=0.05) 5.01 4.70 0.41
CV 12.14 12.42 11.91
Grand mean 23.20 21.27 1.94
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
4.2.2. Shoot yield
The effect of biochar application on the shoot yield of cauliflower is presented in Table 10.
The shoot yield of cauliflower was found higher after the application of biochar in
combination with FYM as compared to control. The highest shoot yield (30.94 t/ha) was
obtained from 20 Mg ha-1 biochar & 12 t/ha FYM application which was similar to 15 Mg
ha-1 biochar & 12 t/ha FYM application but significantly higher than other treatments.
Treatment receiving no biochar and FYM gave the lowest shoot yield (10.28t/ha) which
was significantly lower than other treatments.
30
4.2.3. Root yield
The effect of biochar application on the root yield of cauliflower is presented in Table 10.
Root yield of cauliflower was found higher after application of biochar in combination
with FYM as compared to control. The highest root yield (2.74 t/ha) was obtained from 20
Mg ha-1 biochar & 12 t/ha FYM application which was similar to 15 Mg ha -1 biochar & 12
t/ha FYM application but significantly higher than other treatments. Treatment receiving
no biochar and no FYM gave the lowest biomass yield (1.07 t/ha) which was significantly
lower than other treatments.
4.2.4. Curd diameter
The effect of biochar application on the curd diameter of cauliflower is presented in Table
11. Curd diameter of cauliflower was found higher after the application of biochar as
compared to control. The highest curd diameter (14.82cm) was obtained from 20 Mg ha -1
biochar & 12 t/ha FYM application which was similar to 15 Mg ha -1 biochar & 12 t/ha
FYM application but significantly higher than other treatments. Treatment receiving no
biochar and no FYM gave the lowest curd diameter (8.63cm) which was significantly
lower than other treatments.
4.2.5. Curd yield
The effect of biochar application on the curd yield of cauliflower is presented in Table 11.
Curd yield of cauliflower was found higher after application of biochar in combination
with FYM as compared to control. The highest curd yield (16.62cm) was obtained from 20
Mg ha-1 biochar &12 t/ha FYM application which was followed by treatment of 15 Mg ha -1
of biochar & 12 t/ha FYM application. Treatment receiving no biochar and no FYM gave
the lowest curd yield (4.55t/ha) which was significantly lower than other treatments.
31
Table 14. Effects of biochar application on curd diameter and curd yield of cauliflower at
harvest at Dasrathpur, Surkhet, Nepal.
Treatment Curd diameter(cm) Curd yield(t/ha)
Control 8.63d 4.55 c
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 13.73ab 11.73 b
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 11.60bc 11.08 b
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 11.85b 12.14b
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 14.39a 12.79b
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 14.82a 16.62 a
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 9.34cd 6.49 c
SEM(±) 0.11 0.13
LSD(α=0.05) 2.34 2.80
CV 10.91 14.61
Grand mean 12.05 10.77
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
4.3. Effects of biochar application in combination with FYM on soil properties
4.3.1. Soil pH
The effect of different treatments on soil pH at harvest of cauliflower is presented in Table
15. The effect of biochar application in combination with FYM on soil pH was not
significant among treatments but it was highest (7.06) in treatment with 10 Mg ha -1 biochar
&12 t/ha FYM application followed by 15 and 20 Mg ha -1 of biochar &12 t/ha FYM
amended soil.
32
Table 15.Effect of biochar application on soil pH, soil organic matter, and bulk density of
soil at cauliflower harvest at Dasrathpur, Surkhet, Nepal.
Treatment Soil pH Soil Organic Bulk
matter (%) density(g/cm3
)
Control 6.9 1.93d 1.67a
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 6.8 2.71abc 1.5ab
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 6.97 2.33bcd 1.43bc
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 7.06 2.91ab 1.27bc
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 7.03 2.56bcd 1.30c
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 7.03 3.29a 1.27c
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 6.9 2.04cd 1.37c
SEM(±) 0.012 0.031 0.0086
LSD(α=0.05) 0.25 0.67 0.18
CV (%) 2.02 14.94 7.44
Grand mean 6.97 2.54 1.4
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
4.3.2. Soil organic matter
The effect of biochar application on soil organic matter (SOM) at the harvest of
cauliflower is presented in Table 15. The effect of biochar application in combination with
FYM on soil organic matter was significant among the treatments. The highest (3.29%)
soil organic matter was obtained from 20 Mg ha -1 biochar &12 t/ha FYM application as
compared to other treatments and the lowest was obtained from control.
4.3.3. Bulk density
The effect of different treatments on bulk density at harvest of cauliflower is presented in
Table 15. The effect of biochar application in combination with FYM on soil bulk density
was highly significant. The highest (1.67g/cm 3) soil bulk density was obtained from
control in which no biochar and no FYM were applied whereas the lowest soil bulk density
(1.27g/cm3) was obtained from 10 and 20 Mg ha-1 biochar &12 t/ha FYM application.
33
4.3.4. Primary nutrient contents in soil
4.3.4.1. Nitrogen content in soils
The effect of biochar application on bulk density at harvest of cauliflower is presented in
Table 16. The effect of biochar application in combination with FYM on nitrogen content
in soil was significant. The addition of different doses of biochar has higher nitrogen
content as compared to without the addition of biochar. The highest nitrogen content
(0.07%) was found from 10, 15, and 20 Mg ha -1 biochar &12 t/ha FYM application, and
the lowest (0.051%) nitrogen content was obtained from control.
Table 16. Effect of biochar application in combination with FYM on total nitrogen,
available phosphorous, and available potassium content of soil at cauliflower harvest at
Dasrathpur, Surkhet, Nepal
Treatment Total Available Available
Nitrogen(%) Phosphorous Potassium
(kg/ha) (kg/ha)
Control 0.051c 47c 183.72 b
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 0.065abc 56.33bc 343.97a
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 0.067ab 61ab 318.84a
Biochar @ 10 Mg ha-1 + FYM @ 12 t/ha 0.07a 65.67ab 364.85a
Biochar @ 15 Mg ha-1 + FYM @ 12 t/ha 0.07a 65.67ab 434.02a
Biochar @ 20 Mg ha-1 + FYM @ 12 t/ha 0.07a 71.67a 440.24a
Biochar @ 25 Mg ha-1 + FYM @ 12 t/ha 0.053bc 68.67ab 318.70a
SEM(±) 0.00065 0.60 5.18
LSD(α=0.05) 0.014 12.89 111.74
CV (%) 12.33 11.63 18.28
Grand mean 0.064 62.28 343.47
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
4.3.4.2. Available phosphorous content in the soil
The effect of biochar application on available phosphorous at the harvest of cauliflower is
presented in Table 16. The effect of biochar application in combination with FYM on
available phosphorous contents in soil was found to be significant among the treatments.
The highest available phosphorous content (71. 67Kg/ha) in soil was obtained from 20 Mg
34
ha-1 biochar &12 t/ha FYM application. The lowest available potassium content (47 Kg/ha)
was observed in control in which no biochar and no FYM were used.
4.3.4.3. Available potassium content in the soil
The effect of biochar application on available potassium at harvest of cauliflower is
presented in Table 16. The effect of biochar application on available potassium contents in
soil was highly significant. The highest available potassium content (440.24 Kg/ha) in soil
was obtained from 20 Mg ha -1 biochar application followed by the one with no biochar and
only FYM. The lowest available potassium content (183.72 Kg/ha) was observed inthe
control.
4.4. Effects of nutrient content on cauliflower plants
4.4.1. Nitrogen contents
The effect of biochar application on the nitrogen content of cauliflower plants at harvest is
presented in Table 17. The effect of biochar application on the nitrogen content of plants
was significant. The highest nitrogen content (2.38%) was obtained from 20 Mg ha -1
biochar application followed by 15 Mg ha -1 biochar application and the lowest nitrogen
content was obtained from 25 Mg ha-1 biochar application.
35
Table 17.Effect of biochar application in combination with FYM on total nitrogen, total
phosphorous, and total potassium content in plants of cauliflower at harvest at Dasrathpur,
Surkhet, Nepal.
Treatment Total Total Total
nitrogen phosphorous potassium
(%) (%) (%)
Control 1.73 bc 0.02bc 0.043d
Biochar @ 0 Mg ha-1 + FYM @ 12 t/ha 1.68bc 0.019 bc 0.113ab
Biochar @ 5 Mg ha-1 + FYM @ 12 t/ha 1.50c 0.016c 0.063 cd
Biochar @ 10 Mg ha-1 + FYM @ 12 2.03ab 0.02bc 0.073bcd
t/ha
Biochar @ 15 Mg ha-1 + FYM @ 12 2.14ab 0.021b 0.1abc
t/ha
Biochar @ 20 Mg ha-1 + FYM @ 12 2.38 a 0.028a 0.132a
t/ha
Biochar @ 25 Mg ha-1 + FYM @ 12 1.62bc 0.024ab 0.087 abcd
t/ha
SEM(±) 0.022 0.00022 0.002
LSD(α=0.05) 0.48 0.0049 0.043
CV (%) 14.35 12.95 27.80
Grand mean 1.87 0.021 0.088
Means followed by the same letter (s) in a column are not significantly different at 5%
level of significance as determined by DMRT
4.4.2. Phosphorous contents
The effect of biochar application on the phosphorous content of cauliflower plants at
harvest is presented in Table 16. The effect of biochar application on the phosphorous
content of plants was highly significant. The highest phosphorous content (0.028%) was
obtained from 20 Mg ha-1 biochar application followed by 25 Mg ha-1 biochar application
and the lowest phosphorous content was obtained from 5 Mg ha-1 biochar application.
4.4.3. Potassium contents
The effect of biochar application on the potassium content of cauliflower plants at harvest
is presented in Table 16. The effect of biochar application on the potassium content of
plants was found to be significant. The highest potassium content (0.132%) was obtained
36
from 20 Mg ha-1 biochar application and the lowest potassium content was obtained from
treatment with no biochar and FYM.
5. DISCUSSION
The treatment effects of biochar application obtained during the course of investigations
and the possible reasons for the results are discussed in the section.
5.1. Effects of biochar application in combination with FYM on yield of
cauliflower
The biomass, shoot, root, and curd yields of cauliflower were significantly increased after
the application of biochar along with FYM as compared to control. The highest and the
lowest yields were recorded from the 20 Mg ha -1 biochar along with 12t/ha FYM and
without biochar and FYM application respectively. Our study is supported by Simansky et
al.,(2019) who reported that the application of biochar blended with locally produced cattle
farmyard manure (FYM) increased the yield of peppers (a short-duration crop) by 6%,
15%, and 20% in 1st, 2nd, and 3rd harvests respectively as compared to the control
treatment. Also, a demonstration field trial conducted in Nepal showed that the application
of biochar @1 t ha-1 along with cow urine increased ginger yield by 30%. Similarly, the
application of biochar @2.4 t ha-1 increases cabbage yield by 50% along with the addition
or without the addition of compost, and also application of biochar in combination with
organic amendments was found very effective in increasing tea yield also by 33% in
Barbote, Ilam (ADB Technical Assistance Consultant’s Report, 2016).
The biochar could increase N availability in soil which increased the uptake of nutrients by
plants increasing in yield of cauliflower. A possible explanation for the increase in yield in
biochar amendments plots includes the positive effect of biochar on soil physio-chemical
properties such as enhanced water holding capacity, increased cation exchange capacity
(CEC), and providing a medium for adsorption of plant nutrients and improved conditions
for soil micro-organisms (Sohi et al., 2009). Biochar efficiently adsorbs ammonia (NH 3)
and acts as a binder for ammonia in soil which results in a decrease in ammonia
volatilization from the soil surface (Oya &Iu; 2002; Iyobe et al., 2004).
However, decrease in cauliflower yield was also observed in the treatment with 25
Mg ha-1 biochar along with 12t/ha FYM . Decreases in crop productivity have also been
reported for specific combinations of biochar and soil (Van zweiten et al., 2010;
37
Wisnubroto et al., 2010). Grain yields are decreased by 10% - 23.3% with biochar
application (Asai et al., 2009). According to Spokas et al. 2012 after review of the biochar
literature and found that 30% of the studies reported no significant differences, and 20%
reported negative yield or growth effects (Spokas et al., 2012;Novak et al., 2016). The
decreased crop yield may be attributed to toxic and harmful substances in biochar, which
can reduce nutrient uptake and inhibit plant growth.
5.2. Effect of biochar application in combination with FYM on yield attributing
characters of cauliflower
The effect of biochar application in combination with FYM on plant height of cauliflower
was found to be significant at both 15 and 30 DAT whereas at 45 DAT it was found non-
significant. At 15, 30, and 45 DAT, the tallest plant was recorded from 20 Mg/ha biochar
application in combination with FYM, and the shortest was recorded from without biochar
and FYM application. It was found that the plant growth was significantly higher in treated
plots than in the control after the application of biochar along with FYM to the soil.This
could be due to the effect of biochar application on soil that influence the accumulation of
SOM largely and also helps in the improvement of other soil chemical properties such as
soil pH which in turn improved the quality and productivity of degraded and low-quality
soils (Khan et al., 2013; Bajracharya et al., 2015). Scislowska et al., (2015) reported that
the application of biochar to soils had positive effects on plant growth as biochar
application plays roles in soil nutrient availability, water holding capacity, carbon
sequestration, CEC, and soils pH level. Hence, biochar application has been found to have
a positive effect on enhancing the vegetative growth of crops in the short run. The liming
effect which decreased soil acidity had been suggested as one of the main mechanisms
through which biochar was able to increase the growth of plants (Verheijen et al., 2010).
The effect of biochar application along with FYM on the number of leaves per plant of
cauliflower was found to be non-significant at 15, 30, and 45 DAT. The effect of biochar
application along with FYM in canopy width was found to be significant at 15 DAT and
highly significant at 30 and 45 DAT.
Compost integrated with biochar had a significant effect on the plant height, knob weight,
and yield of knolkhol compared to the sole application of these amendments (Sharma et
al., 2021). Our results were also supported by earlier studies where the application of
biochar along with cattle manure in a coffee agroforestry system increased crop yield of
radish, soybean, chilly, and garlic as compared with only cattle manure amendment soils
38
(Gautam et al., 2017). Increased yield could be attributed to the formation of organic
coatings in biochar pores when mixed with manure, which can hold a higher amount of
nutrients (nitrate and phosphate) and released slowly to plants as and when needed by
plants (Hagemann, 2017; Kamann et al., 2015). Growth parameters of Glycine max such as
plant height (34 cm), leaf area (431 cm 2), and a number of effective nodules per plant (5)
resulted in higher production with the combined application of 25% compost and 75%
biochar (Senevirathne et al., 2019). According to the research conducted in the Rasuwa
district of Nepal, crop yield (ton/ per hectare) of all crops planted within the hill farming
system such as mustard, potato, radish, and garlic were observed to be significantly higher
in the biochar & FYM amended soils compared to only FYM added soils (Gautam et al.,
2017).
5.3. Effects of biochar application in combination with FYM on soil properties
The effect of biochar application on soil pH at harvest of cauliflower was not significant
among treatments and there was a greater pH value in biochar amended soil as compared
to control where biochar and FYM application was not performed. The increase in soil pH
due to biochar application was generally attributed to ash residues which contain
carbonates of alkali and alkaline earth metals,silica, heavy metals, sesquioxides,
phosphates, and organic and inorganic nitrogen (Raison, 1979). Another reason for an
increase in soil pH could be of high surface area and porous nature of biochar that
increased the cation exchange capacity of the soil. (Nigussie et al., 2012) also reported that
there was a decrease in exchangeable Al and soluble Fe in biochar amended soil.
According to research carried out in NARC, Khumaltar reported biochar prepared from
maize stover was found to be alkaline (pH 10.2) in nature. It was evident that the
application of biochar can remediate soil acidity problems in most acid soil and biochar
can also be used for ameliorating soil acidity to some extent (Vista & Khadka, 2017).The
liming effect which decreased soil acidity had been suggested as one of the main
mechanisms through which biochar was able to increase the growth of plants (Verheijen et
al., 2010).
Soil organic matter at harvest of cauliflower was significant and the highest soil organic
matter was observed from 20 Mg ha-1 biochar application which was significantly higher
than other treatments. The increase in soil organic matter was due to an increase in organic
carbon as the biochar application rate increased. An increase in soil organic carbon due to
an increment in the application rate of biochar was observed by many researchers. Higher
39
organic carbon at ancient terra preta compared with adjacent soil was also reported by
Solomon et al., (2007) and Liang et al., (2006). Laird (2008) also mentioned that biochar
application to soil is an effective means of carbon sequestration and that biochar
application improves soil quality and increases crop yield. Under the different tropical
conditions, biochar and manure mixture would significantly increase the efficiency of
organic compost by preventing the rapid decomposition and also the mineralization of
organic materials (Lehmann et al., 2003). This could be because of theability of the biochar
to increase the efficiency of the utilization of the nutrients that are present in both FYM
and VC (Sharma et al., 2021).
The soil bulk density was significantly different among the various rates of biochar
application in combination with FYM. As the porosity of biochar is high, its use in soil
results in a decrease in bulk density by increasing the pore volume (Mukherjee & lal,
2013).
The effect of biochar application on the total nitrogen content of soil at cauliflower harvest
was found to be significant among the treatments. The addition of biochar increased the
nitrogen content of the soil as compared to without the addition of biochar. According to
Glaser et al., (2002) and Lehmann et al.,(2003), biochar application in soil increased the
availability of nitrogen in the soil. Biochar acts as an absorbent of applied organic
fertilizers and retains nutrients such as N, P, and K because biochar has a larger porous
surface area and functional groups (Hue, 2020). Kammann et al., 2015 reported a higher
quantity of N and P in soil solution when biochar was blended with organic fertilizers. The
reason for it is primarily due to the formation of organic coatings in biochar pores, which
can absorb and retain a higher amount of N and P in soil solution (Hagemann et al., 2017;
Kammann et al., 2015).
The phosphorous content in soil at cauliflower harvest was found to be significantly
different among various rates of biochar application along with FYM. The observed
increase in phosphorous after the application of biochar may be due to the presence of a
high amount of phosphorous in biochar. Higher available phosphorous levels in the
biochar amended soils could be due to improvement in the availability of phosphorous as a
result of biochar application (Alburquerque et al. 2013; Asai et al. 2009). Upon biochar
addition, improvement in the availability of a higher amount of phosphorous could be
correlated with soil pH (Pandit et al., 2018). Also in acidic soil, P may be adsorbed with Al
40
and Fe making insoluble compounds (Al-P and Fe-P) and biochar application increases
soil pH towards neutral, which improves P availability in soil solution (Hale et al., 2013).
The effect of biochar application in combination with FYM on available potassium content
was highly significant. Biochar addition increased available K, which is possibly due to
direct K+ addition from biochar ashes. Gautam et al., 2017, reported an increase in
exchangeable K from 176 (control) to 264 cmolc kg -1 upon the addition of biochar blended
cattle manure. Biochar application has also been noted to enhance the growth of K-
Dissolving Bacteria (KDB), and enhance mineral K weathering in soils making more K
available in soil solution (Wang et al., 2018).
5.4. Effects on nutrient contents of plant sample of cauliflower
The effect of biochar application in combination with FYM on nitrogen and potassium
content of plant samples of cauliflower was significant whereas that of phosphorous
content was highly significant. This could be explained by the findings of Yao et al.,
(2013) who reported that the bioavailability and plant uptake of primary nutrients
increased in response to biochar application, particularly in the presence of added fertilizer.
The reason for a higher uptake of primary nutrients (NPK) under high doses of biochar
may be due to the positive effects of biochar on crop growth, along with positive effects on
nutrient (N, P, Ca, and Mg) uptake by crop plants and the availability of soil N, P, Ca and
Mg. Related findings were reported by Zhang et al. (2013). An increase in pH of acidic soil
may decrease Al activity which in turn results in better root growth and nutrient uptake can
be expected. Nutrient uptake is a function of nutrient content and biomass production. The
increased rate of application of biochar increased biomass production which certainly
increased nutrient uptake. The highest nitrogen content in plant tissue of cauliflower was
observed from 20 Mg/ha biochar in the application in combination with 12 t/ha FYM.
These results were sustained by Major et al., (2010) who noted that the application of 20 t
BC ha–1 considerably enhanced N uptake in maize, due to its direct adsorption effect and/or
indirectly through microbial immobilization effect. Major et al., (2010) also stated that N
content in maize grains was improved due to BC incorporation. In support of our
results DeLuca et al., (2015) noted that the incorporation of biochar improved plant N
content which further increased the use efficiency of N. It might be due to NH4 + ion
presence in soil fora long time which might be due to biochar because biochar holds
ammonium ion and makes it inaccessible for microbes to transform it into NO 3 and
considerably minimizes losses of N due to volatilization and leaching in soil.
41
6. SUMMARY AND CONCLUSIONS
A field experiment was conducted to evaluate the effects of biochar application in
combination with FYM on soil properties, yield, and yield attributing characteristics of
cauliflower in sandy loam soils at Dasrathpur, Surhet, Nepal from November 2021 to
February 2022. The experiment was laid out in a Randomized Complete Block Design
with three replications. There were seven treatments which included control, biochar @ 0
Mg ha-1 + FYM @ 12 t/ha , biochar @ 5 Mg ha -1 + FYM @ 12 t/ha , biochar @ 10 Mg ha -1
+ FYM @ 12 t/ha, biochar @ 15 Mg ha -1 + FYM @ 12 t/ha, biochar @ 20 Mg ha -1 +
FYM @ 12 t/ha and biochar @ 25 Mg ha-1 + FYM @ 12 t/ha . Cauliflower was grown as a
test crop. Maize cobs were used to prepare biochar under pyrolytic conditions and it was
applied to the field as per the treatments before transplantation of seedlings of cauliflower.
The result found in the study showed that there was an increase in primary nutrient
contents and soil organic matter in soil from the application of biochar in combination with
FYM resulting in the increase of cauliflower yield as compared to control and FYM only.
The application of biochar in combination with FYM resulted in increased soil pH, soil
organic matter, total nitrogen, available phosphorous, and available potassium in the soil,
and decreased soil bulk density. The biomass, root, and shoot yields, number of leaves per
plant, and canopy width per plant also increased with biochar application in combination
with FYM as compared to control.
Hence from this study, we could conclude that the application of biochar along with FYM
to soil has the potential to improve soil fertility and cauliflower yield. Biochar application
helps in improving the physical and chemical properties of soils such as water holding
capacity and soil nutrients retention, increases soil pH, soil organic matter, total nitrogen,
available phosphorus, available potassium contents of soil, and decreases soil bulk density,
and also enhances plant growth. Biochar application has other benefits such as acidic soil
reclamation, improvement of sandy soil properties, carbon sequestration, and many more.
From this study, it can thus be concluded that the addition of biochar to soil would be of
immense value to increase soil fertility and crop yield. Thus, biochar application is an
42
innovative method due to its potential application for long-term C sequestration, climate
change mitigation, and sustainable soil management. But, biochar should not be used as a
fertilizer alone but should be used as a catalyst and should be blended with other fertilizers
and manures for mobilization of the nutrients. It is not recommended to be used in
excessive doses as a low rate of biochar also has a good effect compared to no application
of biochar whereas too much use of biochar in the soil might cause the problems like soil
alkalinity and nutrient locking being unavailable to the plants and there might not be
optimum utilization of biochar and resources.
This research was conducted in single season, further long term research is
necessary in different agro-climatic regions
Research limited in sandy loam texture, can be done in variable soil textures
Can be done in other crops
43
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APPENDICES
Appendix 1. Weather record during an experiment at Surkhet ( 2021/22)
Maximum mean Minimum mean
Month/ Year Rainfall (mm)
temperature ( ̊C) temperature ( ̊C)
1st fortnight of November 26.2 13.5 0
2nd fortnight of November 27.4 11.5 0.1
1st fortnight of December 22.4 12.4 1.8
2nd fortnight of December 22 8.68 0
1st fortnight of January 20.2 11.06 17.78
2nd fortnight of January 18 8.12 20.32
1st fortnight of February 22.67 9.46 22.86
2nd fortnight of February 25.57 12.21 0
(Source: Department of hydrology andmeteorology)
Appendix 2. Analysis of variance table for plant height of cauliflower at 15 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 1.3673 0.68366 0.7132 0.50971
Treatment 6 18.2966 3.04944 3.1813 0.04168 *
Error 12 11.5026 0.95855
Total 20
59
Appendix 4. Analysis of variance table for plant height of cauliflower at 45 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 171.74 85.870 4.3381 0.03822
Treatment 6 155.66 25.943 1.3106 0.32405
Error 12 237.53 19.795
Total 20
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.74206 0.37103 2.2302 0.15012
Treatment 6 2.48903 0.41484 2.4936 0.08393
Error 12 1.99634 0.16636
Total 20
60
Appendix 7. Analysis of variance table for the number of leaves of cauliflower at 45
DAT as influenced by different doses of biochar application in combination with
FYM at Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 1.1010 0.55048 5.4187 0.02105
Treatment 6 1.7867 0.29778 2.9312 0.05335
Error 12 1.2190 0.10159
Total 20
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 5.298 2.6491 1.8109 0.205443
Treatment 6 46.084 7.6806 5.2505 0.007206 **
Error 12 17.554 1.4628
Total 20
61
Appendix 10. Analysis of variance table for canopy width of cauliflower at 45 DAT as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 590.59 295.293 10.7784 0.002091
Treatment 6 902.51 150.418 5.4904 0.006045**
Error 12 328.76 27.397
Total 20
Appendix 11. Analysis of variance table for biomass yield of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 68.46 34.232 4.3093 0.03886 *
Treatment 6 1242.88 207.146 26.0766 3.225e-06
Error 12 39.595 2.64
Total 20
Appendix 12. Analysis of variance table for shoot weight of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 51.35 25.676 3.6767 0.05683
Treatment 6 1071.56 178.593 25.5741 3.586e-06 ***
Error 12 83.80 6.983
Total 20
62
Appendix 13. Analysis of variance table for root weight of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 1.3293 0.66463 12.431 0.00119
Treatment 6 6.9989 1.16649 21.817 8.456e-06 ***
Error 12 0.6416 0.05347
Total 20
Appendix 14. Analysis of variance table for curd yield of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 2.006 1.003 0.4045 0.676
Treatment 6 294.686 49.114 19.8089 1.414e-05 ***
Error 12 29.753 2.479
Total 20
Appendix 15. Analysis of variance table for curd diameter of cauliflower at harvest as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 6.008 3.0042 1.7378 0.217368
Treatment 6 105.557 17.5929 10.1770 0.000406***
Error 12 20.744 1.7287
Total 20
63
Appendix 2. Analysis of variance table for soil pH as influenced by different doses of
biochar application in combination with FYM at Dasrathpur, Surkhet, Nepal
(2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.035238 0.017619 0.888 0.4369
Treatment 6 0.113333 0.018889 0.952 0.4951
Error 12 0.238095 0.019841
Total 20
Appendix 4. Analysis of variance table for soil bulk density as influenced by different
doses of biochar application in combination with FYM at Dasrathpur, Surkhet, Nepal
(2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.10286 0.051429 4.7299 0.030572
Treatment 6 0.38667 0.064444 5.9270 0.004443 **
Error 12 0.13048 0.010873
Total 20
64
Appendix 5. Analysis of variance table for total nitrogen content of soil as influenced
by different doses of biochar application in combination with FYM at Dasrathpur,
Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.00026600 1.3300e-04 2.1375 0.1607
Treatment 6 0.00117133 1.9522e-04 3.1375 0.0435 *
Error 12 0.00074667 6.2222e-05
Total 20
65
Appendix 8. Analysis of variance table for total nitrogen content in plant sample as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.27692 0.138462 1.9199 0.18905
Treatment 6 1.82696 0.304494 4.2222 0.01626 *
Error 12 0.86541 0.072117
Total 20
Appendix 9. Analysis of variance table for total phosphorous content in plant sample
as influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 4.6923e-05 2.3461e-05 3.0576 0.084492
Treatment 6 3.0099e-04 5.0166e-05 6.5379 0.002959 **
Error 12 9.2077e-05 7.6730e-06
Total 20
Appendix 10. Analysis of variance table for total potassium content in plant sample as
influenced by different doses of biochar application in combination with FYM at
Dasrathpur, Surkhet, Nepal (2021/22)
Source of Degree of
variation freedom Sum of square Mean square F value Probability
Replication 2 0.0022923 0.00114614 1.9336 0.18711
Treatment 6 0.0168653 0.00281088 4.7420 0.01064 *
Error 12 0.0071132 0.00059276
Total 20
66
BIOGRAPHIC SKETCH
The author was born on 3rd august 1995 at Dullu Municipality ward no. 10, Dailekh as the
eldest daughter of Mr. Janak Bahadur Thapa and Mrs. Belmati Thapa. She completed her
School leaving Certificate from Surkhet Horizon Academy, Surkhet, in 2067. She
completed her intermediate of Science (10+2) from Khwopa Higher Scondary School,
Bhaktapur in 2069 and B.Sc.Ag degree from Tribhuvan University, Campus of Live
Sciences, Tulsipur, Dang, Nepal in 2075. She secured first division in SLC& 10+2 and
distinction in B.Sc.Ag. Then she was enrolled in M.Sc.Ag course majoring Soil Science at
Agriculture and Forestry University, Rampur, Chitwan in 2076.
This author is an innovative person with keen interest in research. Currently she is working
as a crop development officer at Soil and watershed management office,Surkhet. She is a
gentle and diligent person with strong will power for the advancement of soil science. She
always opts for excellence and wishes to contribute to the nation through her hard work.
The author is married, has parents and two younger brother and sister and spends very
happy life with her family.
Author
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