vasee emit ng pn) Environmental Studies ome » Course ® Course UacerRetnenent(Versan 20) ® UG Coures- Day Tenralogy ® Oaty Busines Managemen (Vorsn 2)» Eneronmenal Stes ®t Nareb"7 Maren» Lean f-LAND RESOURCES Lesson 7. LAND RESOURCES Module 2, Neural resources Lesson 7 LAND RESOURCES ‘A nation that destroys its soils destroys itself” Franklin D. Roosevelt 7.1 Land as a Resource Land area constitutes about 1/5 of the earth surface. To mect out the challenging demand of food, fibre ané fuel for human population, fodder for animals and industrial raw material for agro based industries, efficient management of land resources will play critical role. Soil, water, ‘vegetation and climate are basic natural resources for agricultural growth and development 7.2 Land Degradation Due to increasing population, the demands for arable land for producing food, fibre and fuel wood is also increasing. Hence there is more and. ‘more pressure on the limited land resources which ae getting degraded due to over-exploitation. Nearly $6% of total geographical area ofthe county is sufering due ta land resource degradation, Out of 17 million hectare canal itigated area, 34 rllion ectate is suffering. from water Jogging and salinity. Soil erosion, water logging, salinization and contamination ofthe sol with industrial wastes like fly-ash, press mud or heavy metals all cause degradation of land. 73 Soil Erosion Soil erosion refers to loss or removal of superficial layer of soll duc to the action of wind, water and human factors. In other words, it ean be defined as the movement of soil components, especially surface-litter and topsoil from one place to another, It has becn estimated that more than 5000 million tonnes topsoil is being eroded annually and 30% of total eroded mass is getting loosed tothe sea It rsuls in the loss of fertility. I basically is of two types, viz. geologic erosion and accelerated erosion, Various factors which affect soil erosions include soil type, vegetation cover, slope of ground, soil mismanagement and intensity and amount of rainfall, Wind is also responsible for the land erosion through saltation, suspension and surface erep. Inorder to prevent soil erosion aad conserve the sol the following conservation practices are employed, + Conservation ill farming, Contour farming and Terracing + Strip cropping and alley cropping + Wind breaks or sheltrbelts ig. 7A Terracing Fig, 7.2 Shelterbelts Fig. 73 Conservational tillage (USDA,2007) 114 Salinization refers to accumulation of soluble salts inthe soil. Concentration of soluble salts increases due o poor druinage facilities. In dry land areas, salt concentration increases where poor drainage is accompanied by high temperature. High concentration of salts affects the process of water absorption hence affets the productivity, 15 Water Logging Excessive utilization of isigation may disturb the water balance which can lead to water logging due to rise of water table Anaerobic condition duc t0 poor availability of oxygen in waterlogged soils may affect respiration process in plants wiich will ultimately affect the productivity of water logged soi 16 Desertification Desertification is @ process whereby the productive potential of arid or semiarid lands falls by fen percent or more. Desertification ischaracterized by devegetation and depletion of groundwater, salinization and severe sol erosion 7.6.1 Causes of desertification + Deforestation + Overgrazing + Mining and quarrying 17 Shifting Cultivation Shifting cultivation is a practice of slash and bum agriculture adopted by tribal communities and is a main cause for soil degradation particularly tropical and sub tropical regions. Shifting cultivation which is also popularly known as “Jhum Cultivation’ has lead to destruction of forest in hilly areas 1t is responsible for soi erosion and other problems related to land degradation in mountainous areas, 8 Man Induced Landslides Human race has exploited land resources for his own comfort by constructing roads, railway tracks, canals for irrigation, hydroelectie projecs, arge dams end reservoirs and mining in hilly areas, Moreover productive lands under erop production ave decreasing because of development activites. These factors are affecting the stability of hillslopes and damage the protective vegetation cover. These activities are also responsible to upset the balance of nature and making such areas prone to landslides. ‘use caret ing peace on) rere Ses