Received: 5 November 2019 Revised: 16 June 2020 Accepted: 17 June 2020

DOI: 10.1002/ird.2504

RESEARCH ARTICLE

Evaluation of the irrigation water quality and cropped area

of shrinking peri-urban agriculture in the Gadap Basin,
Karachi: An application of Wilcox's classification and
geospatial techniques

Razzaq Ahmed1 | Shaukat Hayat Khan2 | Khalida Mahmood3 | Ahsanullah4

1
Department of Geography, Federal Urdu
University of Arts, Science and Abstract
Technology, Karachi, Pakistan The Gadap Basin has been an important provider of agricultural commodities
2
National Institute of Oceanography, to the Karachi metropolis for centuries. However, in recent decades it has been
Karachi, Pakistan
noted that agricultural activities in this peri-urban area of Karachi have shown
3
Department of Geography, University of
Karachi, Pakistan
a declining trend. In view of the current scenario, this study focuses on the
4
Geoinformatics, Institute of Space and evaluation of irrigation water quality being used in the Gadap Basin. In order
Technology, Karachi, Pakistan to carry out this study, Wilcox's classification methods of Na+% (sodium
percentage) and SAR (sodium adsorption ratio) have been applied. The results
Correspondence
Razzaq Ahmed, Department of comprise 13 water samples collected from various localities over a period of
Geography, Federal Urdu University of two decades (1997–2016), which clearly show that with the passage of time
Arts, Science and Technology, Gulshan
water quality has degraded badly; in particular, sodium concentration that has
Campus. Karachi, Pakistan.
Email: razzaqahmed@fuuast.gov.pk increased substantially especially in the vicinity of sand and gravel excavation
sites. According to Na+% calculation during 1997, 100% of samples were
Funding information
suitable for irrigation whereas in 2016 it had dropped to almost 50%. Similarly,
Dean, Faculty of Science, University of
Karachi, Pakistan the SAR has gone down, showing degradation of irrigation water quality.
Moreover, the results have also been presented using geospatial techniques.
The satellite imageries discriminate the sharp decline and degradation of
agricultural land (60%) in the basin during the study period 1997–2016.

KEYWORDS
Gadap Basin, geospatial techniques, irrigation water quality, peri-urban, Wilcox's classification

Résumé
Le bassin de Gadap est resté un important fournisseur de produits agricoles
dans la métropole de Karachi depuis des siècles. Cependant, au cours des
dernières décennies, il a été constaté que les activités agricoles dans cette zone
périurbaine de Karachi ont affiché une tendance à la baisse. Compte tenu du
scénario actuel, cette étude se concentre sur l'évaluation de la qualité de l'eau
d'irrigation utilisée dans le bassin de Gadap. Pour mener à bien cette étude, les

*
Évaluer la qualité de l'eau d'irrigation et la superficie cultivée de la contraction de l'agriculture périurbaine dans le bassin de Gadap, Karachi:
application de la classification de Wilcox et des techniques géospatiales.

Irrig. and Drain.. 2020;1–10. wileyonlinelibrary.com/journal/ird © 2020 John Wiley & Sons, Ltd. 1
2 AHMED ET AL.

méthodes de classification de Wilcox ont été appliquées avec Na+%

(pourcentage de sodium) et SAR (taux d'adsorption du sodium). Les résultats
comprennent 13 échantillons d'eau prélevés dans diverses localités sur une
période de deux décennies (1997–2016), ce qui montre clairement que la
qualité de l'eau s'est dégradée au fil du temps, en particulier la concentration
de sodium qui a considérablement augmenté, en particulier aux alentours des
sites d'excavation de sable et de gravier. Selon les calculs de Na+% effectués en
1997, 100% des échantillons étaient adaptés à l'irrigation, tandis qu'en 2016, ils
étaient tombés à près de 50%. De même, le SAR a diminué, montrant une
dégradation de la qualité de l'eau d'irrigation. De plus, les résultats ont
également été présentés à l'aide de techniques géospatiales. Les imageries
satellites distinguent le déclin et la dégradation prononcés des terres agricoles
(60%) dans le bassin au cours de la période étudiée de 1997 à 2016.

MOTS CLÉS
Bassin Gadap, techniques géospatiales, qualité de l'eau d'irrigation, périurbain, classification de
Wilcox

1 | INTRODUCTION the area is arid to semi-arid with no perennial river

system, the agriculture practised is based on groundwater
Rural areas capture the essence of nature as being mainly reservoirs extracted through tube wells. Rain is scarce
associated with agricultural activity. Rural populations and highly variable from year to year, so groundwater
perceive rurality as having open green farms where agri- has become an asset in this region. Consequently, its
cultural activity continues (Jones, 1995). The rural areas indiscriminate and excessive use has caused environmen-
of the global South portray a picture of traditionality, tal hazards such as water table depletion, seawater
simplicity, austerity and sometimes poverty, although intrusion, soil salinization and agricultural decline.
they are the home of the majority of the population. Urban and peri-urban areas play a significant role in
Similarly in Pakistan, two-thirds of the population reside feeding large urban centres around the world. Many large
in rural areas engaged in agriculture, which is still the cities with millions of people are fed by peri-urban agri-
largest employment provider with 42.3% of the country's culture systems, for example Beijing, Jakarta, Bangkok,
total workforce (Ministry of Finance, 2017). Despite this, Addis Ababa, Dar es Salaam, Cape Town, Johannesburg,
the sector is facing many challenges such as lack of Toronto, North American cities located from New York
optimization of water by improvement in water supplies, to Texas and major urban centres of Europe. The
poor infrastructure in rural areas that reduces access of available literature such as Horvath (1969), Egziabher
farm products to markets and increasing urban land-use, et al. (1994), Lynch (1994), McCorkle (1999), Maynard
which puts intense pressure on rural land especially that and Hochmuth (2007), Archbold and Goldsacker (2011),
located on the fringes of major urban centres. Mkwambisi et al. (2011), Indraprahasta (2013), Padgham
Agriculture, being the backbone of the country's et al. (2015), Wandl and Magoni (2017) and Ayambire
economy, depends extensively on irrigation, hence this et al. (2019) signifies the importance of peri-urban
makes it a significant consumer of water resources. The farming. Mougeot (2006, 2011) emphasized the impor-
Karachi division, the most urbanized area in the country, tance of such agriculture by considering it an integral
has very limited agricultural land and groundwater component of the urban food chain and a major stake-
resources. Areas located in the vicinity of the Karachi holder in urban food security. Peri-urban agriculture is
suburbs where agriculture has been practised for a long not just limited to providing fresh vegetables and fruit to
time have witnessed a sharp drop in water supplies dur- city dwellers, but also involves raising livestock for the
ing the last 4–5 years due to the non-availability of water urban market to fulfil dairy needs and is reckoned to be a
(personal communication). This water shortage is caused fast flourishing industry around urban centres.
either by an increase in dry periods or receding water Farming in the city (urban and peri-urban
tables caused by anthropogenic activities. As climatically agriculture, UPA) is too often seen in municipalities as a
AHMED ET AL. 3

problem to be eradicated rather than as a part of the SDG (Sustainable Cities and Communities). Karachi
solution for making the city and its environment more Development Authority (Karachi Development Authority
sustainable. Urban agriculture attracts the attention of (KDA), 1972) has marked the Gadap and Malir areas for
municipal policy makers in developing countries, who commercial agriculture but regrettably it has been badly
realize the fact that properly managed agriculture ignored by agricultural planners and policy makers.
can make a major contribution to cities’ food security, These highly productive areas are now under the threat
ecological functions, resource use efficiency and climate of urbanization, and land grabbers are encroaching on
change. Urban and peri-urban agriculture has immense these areas to acquire the land for urban construction.
potential to provide employment and makes a productive There has been no systematic work conducted on this
use of open land (Mougeot, 2006). It also contributes to component of the farming system. Kausar (2015) is the
better nutrient status and improves the well-being of only available document that has focused on urban and
urbanites and peri-urbanites (Tsuchiya et al., 2015). peri-urban agriculture of the Karachi division. The
Systematic studies are available on the degradation current study does not focus on the production of
of natural resources posed by urban agricultural mal- peri-urban areas but is based on evaluating the quality
practices (Muster, 19971). The study on the environmen- of irrigated water and on mapping the temporal change
tal effects of open space vegetable production in Dar es of agricultural land in the Gadap Basin.
Salaam found few serious agrochemical pollution or soil
erosion problems but all of them were manageable.
Rapid urbanization especially in developing countries 2 | STUDY AREA
exerts much pressure on urban and peri-urban agricul-
ture (Pribadi and Pauleit, 2015). This phenomenon Peri-urban areas around large urban centres and
threatens urban ecological services and the fresh supply megacities have always been very important (Pribadi and
of agricultural commodities to city dwellers. Urban and Pauleit, 2016). The study area—the Gadap Basin—has
peri-urban areas of Karachi have experienced massive been a main source of fresh vegetables and fruit for Kara-
urban land expansion in the past few decades (Kausar chi City in the past. The farmers of Gadap grew a variety
et al., 2014). Currently the peri-urban localities of Kara- of fresh vegetables and fruit which were supplied to the
chi such as Gadap, Kathore, Sharafi Goth, etc. are facing Karachiites. As Karachi continued to grow and prosper
various environmental threats besides urban sprawl, with increasing urbanization and industrialization,
such as overgrazing, water scarcity and lowering of construction activities increased over the years, increas-
water tables. Field surveys of these areas reveal the vul- ing the need for sand and gravel. The beds of the Malir
nerability to dry conditions leading to decline of farming River and its tributaries bed have been the centre of
activity. The resulting deterioration in scenic rural attraction for gravel and sand grabbers. The city's require-
beauty is now turning these productive areas into ment for construction material from the Malir River has
unploughed barren lands. played a drastic role in the shape of an environmental
Pribadi and Pauleit (2016) and Wandl and Magoni disaster for the entire river basin, threatening the ecologi-
(2017) suggested the integration of peri-urban agriculture cal balance of the area. The excavation of sand and gravel
into urban planning in order to understand the socio- from the Malir River bed has also affected the water table
economic role of farming needs and sustainability. In the in the surrounding catchment areas; this has gone down
Brussels metropolitan region, a large segment of the from 12 m (1980s) to 90 or 120 m (personal communica-
population is in favour of the protection of farming land- tion). Though the administration has imposed a complete
use in peri-urban fringes (Boulanger et al., 2004). ban on the excavation of sand and gravel, it is still going
Addo (2010) documented such areas as an integral part on illegally.
of farming systems in developing countries. The develop- The Gadap Basin is considered a sub-basin of
ment of such areas can boost overall economic develop- the Malir Basin and has its own distinct watersheds. The
ment; they also provide food security and ensure basin comprises three geomorphic units, namely: the
employment opportunities especially for the rural popu- hilly catchment, the Gadap Plain and the lower
lation. However, in Pakistan this area of research has basin (Ahsanullah, 1971; Blanford, 1879). Geologically
been greatly neglected by researchers, although the the study area is a large dome like a syncline basin
county is committed to achieving the target of the 11th surrounded by mountain ranges on three sides, namely
Manghopir (west), Khand anticline (north) and Pawalo
1
Muster G (1997). Environmental problems of urban agriculture - A
anticline (east) made up of the Mancher, Gaj and Nari
case study of Dar es Salaam, Tanzania. Urban vegetable promotion formations in the north of Karachi division (Figure 1).
project, Dar es Salaam, Tanzania (unpublished). The lower Nari and the Gaj rocks were laid down
4 AHMED ET AL.

F I G U R E 1 The Gadap Basin

(100–200 m + MSL (mean sea level)) is
located to the north of Karachi. It is a
sub-basin of the Malir, drained by the
Lyari, Watanwari, Thaddo and Konkar
rivers. The Pawelo anticline in the east
separates it from the Malir Basin. The
western border is formed by the
low-elevation hills of Manghopir which
separate the basin from the Hab Valley
[Colour figure can be viewed at
wileyonlinelibrary.com]

mainly under marine conditions, but the Manchar 3 | METHODS

sandstones are indicative of a changing estuarine and
fluviatile period (Khan, 1979). Most of the area is The present study consists of two phases. The first was
covered by alluvial deposits of recent origin carried by carried out in 1997 while the second phase was
sheet floods during rain from the catchment areas of conducted in 2016 to evaluate the water quality for irriga-
Watanwari, Thaddo and Konkar. These rain-fed streams tion purposes. The data were collected through extensive
(locally nadi) are the main source of underground water. field surveys in both years. The samples were collected
The western part of the basin is drained by the Lyari from 13 locations (the same in 1997 and 2016, Table 1)
River. In the upper course Watanwari nadi consists of using a non-random sampling method. The sampling
the Bombari and Kirmatiani, which join near Gadap
City (a small marketplace), then becomes buried in the
south of the Gadap Plain due to huge deposits of gravel TABLE 1 List of sample sites and their GPS coordinates
and sand resulting from the construction of urban
S. No. Sample location Latitude Longitude
infrastructure. During the Pleistocene to Recent periods,

0 00
the Watanwari nadi most probably connected with the 1 Sohbat Khan farm 25 4 28.56 67
160 10.9200
channel of Safora nala that drains into the Malir River. 2 Abdul Ghani farm 25
50 31.2000 67
150 13.6800
The area has also been disarticulated by the process of 3 Mangio Jokhio 25
60 02.5200 67
150 24.1200
river piracy (Khan, 1979). 4 Gadap City
0
25 7 33.24 00
67
140 09.6000
Previously this area was used as a pasture land; 5 Murid goth 25
70 56.2800 67
130 57.0000
nomadic tribes from Lower Sindh migrated here during
6 Nasrullah Baloch Bagh 25
80 43.8000 67
130 40.4400
rainy seasons with their cattle. Now the area is inhabited
7 Ramzan Lassi goth 25
70 41.1600 67
130 32.1600
by Baloch and Sindhi tribes who migrated from

0 00
Lasbela and Lower Sindh respectively. The water aquifer 8 Hussain Baloch goth 25 7 36.48 67
120 07.5600
of the study area largely comprises unconsolidated to 9 Rustam Bagh 25
80 22.2000 67
120 30.9600
consolidated sand and gravel which is Miocene to 10 Gohram goth 25
80 40.5600 67
090 50.4000
Pleistocene/Recent in age (Khan, 1979). The hilly catch- 11 Ilyas farm 25
90 14.7600 67
110 55.3200
ment is entirely covered with sandy limestone, sandstone
0 00
12 Konkar 25 3 47.88 67
160 12.0000
and mudstone of the Gaj formation (Pithawalla
13 Khameso 25
30 50.4000 67
150 36.7200
et al., 1946).
AHMED ET AL. 5

was conducted considering ease of access to the sampling The Na% is classified into five categories as: excellent
point, land-use type, entire coverage of the area within below 20, good –20 to 40, permissible –40 to 60, doubtful
the allocated budget and social set-up of the local −60 to 80 and unsuitable above 80 (Wilcox, 1955);
community, as the entry is restricted in local localities.
When collecting the samples, all standard procedures • the sodium adsorption ratio (SAR) is calculated by
were taken into consideration. The samples were using the following formula:
collected in polythene drinking water bottles cleaned by
distilled water, and after collection the samples were
stored in an icebox. The 1997 samples were analysed by Na +
SAR = 2+
+ Mg2 +
ð2Þ
SCOPE, Gulshan-e-Iqbal, Karachi, whereas the later ones √ Ca 2
were done by the PCSIR Laboratories Complex, Karachi.
The application of satellite remote sensing in the field
of agricultural monitoring, crop mapping, yield estima- The resultant SAR value is grouped into four classes as:
tion, crop classification and crop health is widely recog- excellent below 10, good −10 to 18, doubtful −18 to
nized. After Landsat and SPOT, now Sentinel 1 and 26 and unsuitable above 26 (Wilcox, 1955).
2 data have also been applied in agricultural studies
(Ahsanullah, 2018; Mandanici and Bitelli, 2016; Veloso
et al., 2017; Zhang et al., 2017). In the current study two 4 | ANALYS IS
images (1997 and 2016; scene 152/043) of Landsat TM
5 and OLI 8 have been used. These imageries were The Gadap study area has been an important source
downloaded from the USGS website which provides geo- of fresh vegetables and fruit for Karachiites; however,
metric corrected products. After completing the stacking because of socio-environmental issues agricultural activ-
and atmospheric correction procedures with ERDAS ity in Gadap is declining. These issues were not under
software, the images were classified into four land-use consideration in the current study, but since the area is
categories: Orchid + vegetables, Orchid, Vegetables + of agricultural importance, the water samples were exam-
crop and Natural vegetation, on ArcGIS using a ined for irrigational suitability using two irrigational
supervised classification method on TM 5, 1 to 5 band suitability indices, sodium percentage (Na+%) and SAR.
and OLI 8, 2 to 7 band (Liu and Zhang, 2019). The The Na+% of all the samples for 1997 and 2016 is
selected data are cloud-free of the post-monsoon period given in Figures 2 (a) and (b). The results clearly show
of both study years. that the water quality of the Gadap Basin was suitable for
Irrigation water, either surface or pumped from agricultural purposes more than two decades ago. Out of
wells, contains certain chemical substances in solution, 13 sampling locations, one sample that represents Abdul
dissolved from the rocks or soil through which the water Ghani farm had excellent Na+% in the irrigation water,
has passed. The concentration of these dissolved chemi- whereas 5 samples were ‘good’ and the remaining 7 were
cal constituents determines the quality of the water for permissible, which shows that 100% of the samples were
irrigation (Wilcox, 1955). The amount of sodium salt pre- fit for irrigation purposes (Table 2). Hence agriculture
sent in water is referred to as sodicity. An excess amount was flourishing in the area during the 1990s. However,
of sodium in irrigation water has an adverse effect on soil significant deterioration in water quality was observed in
composition that gradually leads to soil degradation. It 2016 (Figure 2(b)). Out of the 13 locations only one (sam-
has been generally observed that agriculture in the Gadap ple 8, Hussain Baloch Goth) was ranked as ‘good’ in
area has reduced rapidly in last few decades, which might 2016, while 6 samples were in the category ‘permissible’
be due to declining irrigated water quality. To evaluate and the remaining 6 fell in ‘doubtful’ (Table 2). It shows
the water quality of the Gadap Basin for irrigation that currently only 50% of samples are useful for irriga-
purposes two methods, sodium percentage (Na+%) and tion purposes. The worst change of condition was
sodium adsorption ratio (SAR), were selected: observed in sample 2 of Abdul Ghani farm that dropped
from excellent to permissible in 2016 (Figure 2(d)),
• the sodium percentage (Na+%) may be obtained from followed by samples 1, 7 and 5. The temporal change of
absolute and relative concentration of the main Na+% presented in Figure 2(c) indicates that spatially
cations: these sample sites are concentrated on the eastern and
central side of the study area, especially sites located
along major roads.
Na + + K + The SAR of 13 samples collected in 1997 and 2016 is
Na + % = × 100 ð1Þ
Ca2 + + Mg2 + + Na + + K + presented in Figures 3(a) and (b). The SAR values also
6 AHMED ET AL.

F I G U R E 2 Sodium
percentage of both selected
years (a) and (b), its 19-year
change in the study area (c) and
sodium concentration (d).
Interpolation (a)–(c) was done
by the ArcGIS–Spline tool
[Colour figure can be viewed at
wileyonlinelibrary.com]

TABLE 2 Na% of 13 samples collected from the study area in 1997 and 2016

1997 2016 Na% change

S. No. Sample location Na% Class Na% Class 1997–2016

1 Sohbat Khan farm 34.4 Good 66.1 Doubtful −31.7
2 Abdul Ghani farm 6.0 Excellent 55.7 Permissible −49.7
3 Mangio Jokhio 45.4 Permissible 64.8 Doubtful −19.4
4 Gadap City 44.0 Permissible 53.3 Permissible −9.31
5 Murid goth 39.7 Good 67.1 Doubtful −27.5
6 Nasrullah Baloch Bagh 43.2 Permissible 59.4 Permissible −16.1
7 Ramzan Lassi goth 38.4 Good 66.2 Doubtful −27.8
8 Hussain Baloch goth 42.0 Permissible 37.1 Good 4.84
9 Rustam Bagh 44.6 Permissible 68.5 Doubtful −23.8
10 Gohram goth 38.8 Good 43.3 Permissible −4.49
11 Ilyas farm 36.1 Good 47.4 Permissible −11.3
12 Konkar 47.6 Permissible 65.1 Doubtful −17.5
13 Khameso 45.7 Permissible 53.0 Permissible −7.24

show almost the same placement of samples as observed (sample 9) had a significant drop of 23.6 (from good to
in the previous index (Na+%). In 1997, 9 out of 13 samples unsuitable), followed by samples 3 and 5 (Figures 3
were placed in the category ‘good’, 3 samples scored (c) and (d)). The results also show little improvement of
‘doubtful’ and only one was ‘unsuitable’, while the SAR values in two sample sites (sample 8 and 10).
majority of the samples of 2016 fell in the category of As discussed in the preceding paragraphs, the irri-
either doubtful or unsuitable, and none met the criteria gated water quality of the Gadap Basin has been deterio-
of good or excellent (Table 3). The temporal change in rating over the past few decades. In order to evaluate the
SAR from 1997 to 2016 indicates that Rustum Bagh impact of deteriorating water quality in the study area,
AHMED ET AL. 7

F I G U R E 3 Sodium
adsorption ratio of both selected
years (a) and (b), its 19-year
change in the study area (c) and
SAR values (d). Interpolation
(a)–(c) was done by the
ArcGIS–Spline tool [Colour
figure can be viewed at
wileyonlinelibrary.com]

TABLE 3 SAR of 13 samples collected from the study area in 1997 and 2016

1997 2016 SAR change

S. No. Sample location SAR Class SAR Class 1997–2016

1 Sohbat Khan farm 10.5 Good 25.3 Doubtful −14.8
2 Abdul Ghani farm 16.5 Good 21.5 Doubtful −5.03
3 Mangio Jokhio 18.0 Good 33.9 Unsuitable −16.0
4 Gadap City 22.3 Doubtful 22.1 Doubtful 0.18
5 Murid goth 16.9 Good 29.5 Unsuitable −12.7
6 Nasrullah Baloch Bagh 17.1 Good 23.5 Doubtful −6.38
7 Ramzan Lassi goth 27.5 Unsuitable 26.5 Unsuitable 1.01
8 Hussain Baloch goth 18.0 Good 13.1 Good 4.89
9 Rustam Bagh 15.6 Good 39.2 Unsuitable −23.6
10 Gohram goth 16.5 Good 11.7 Good 4.77
11 Ilyas farm 16.3 Good 14.4 Good 1.91
12 Konkar 21.8 Doubtful 31.3 Unsuitable −9.52
13 Khameso 19.0 Doubtful 18.9 Doubtful 0.07

RS–GIS techniques were used. By considering the The satellite image of 1997 reveals that primarily
years of water samples collected for chemical analysis, cultivation was concentrated mainly in the western part
two cloud-free satellite imageries (18 October 1997 and of the Gadap Basin, and a secondary concentration was
22 October 2016) of Landsat 5 and 8 were selected that found in the east between Thaddo and Konkar nadi
provide an opportunity to measure the temporal change (Figure 4(a)). The central part of the basin (comprising
in the study area over a period of 20 years—the the land between Thaddo and Watanwari) was not
study period. developed as intense cultivated land. The remaining part
8 AHMED ET AL.

F I G U R E 4 Land-use change in the study

area over of a period of 19 years. The results
obtained by satellite data set of Landsat 5 and
8 [Colour figure can be viewed at
wileyonlinelibrary.com] [Colour figure can be
viewed at wileyonlinelibrary.com]

of the basin was mostly dominated by natural vegetation During the survey, it was also attempted to find out
which is mainly thorny bushes of kikar (Vachellia local perceptions about the decline in agriculture. Almost
nilotica). These bushes are the only source of fuel for all the residents shared the common opinion that the ille-
Gadap's residents. The total agricultural land area gal excavation of sand and gravel from the river beds is
calculated through the classified image was 1560 ha the cause of decline in the water table, which has
(3860 acres) in 1997. gone down to approximately 120 m from 60 m in 1997.
Figure 4(b) shows the marked decrease of agricultural Besides the above-mentioned fact, traditional agricultural
land in the study area. This downward trend clearly pre- practices have also been observed personally by the
sents that the agriculture in entire basin has immensely authors in the area, which could also be another reason
deteriorated during 1997 to 2016. After classification of for the degradation of agricultural land in the Gadap
the image a reduction is found in cultivated land of Basin. Although none of the residents showed concern
approximately 1000 ha (2470 acres), which is 64% less about the decline of irrigated water quality in the basin,
than the area of 1997. Now agriculture is mainly confined the results however indicate that this could also be one of
in the central and western parts. A deprived situation is the reasons.
found in the eastern side of the basin that has suffered Due to the degradation of agricultural land in the area
much in land degradation. The results obtained from the farmers are changing profession, especially the young
analysis of satellite data support the outcomes of the generation are now doing jobs in nearby industrial
chemical analysis (Na+% and SAR) of water samples. units—the situation is quite clear in Hussain Baloch
AHMED ET AL. 9

Goth (sample site 8)—or establishing poultry farms if Ahsanullah. (1971) Report on Landforms and drainage basins in
they have enough capital. The psychological impacts of Karachi region. Karachi, Pakistan: Master Plan Department,
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ture, particularly truck farming/market gardening, in the Mougeot, L.J.A. and Sawio, C.J. (1994) Cities feeding people: an
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