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Compiled by Michelle Sequeira and Pranav Yadav WATER RESOURCES Importance: Rainfall seasonal. Crops grown throughout. Some areas receive more than others. Rice grown everywhere. Rainfall highly erratic & unpredictable Some crops require more than others Some soils don t absorb as much water as others Means: Conventional Wells, Tube wells, Canals, Tanks Non-conventional Furrows, Sprinkler, Drip, Rainwater harvesting WELLS: dugout/hollow made in ground Places: Northern Plains, UP, Bihar Why in Northern Plains? Underground water table is high as region is drained by perennial rivers Region has alluvial soil which is soft and easy to dig Farmers have small landholdings which facilitate the building of wells as it occupies less space Advantages: Cheap Easy Subjected to less evaporation Occupies less space Convenient to dig by individual farmers Underground water is rich in minerals which add to the fertility of the soil Disadvantages: Wells may run dry due to excessive use Water table decreases in summer Evaporation is higher for unlined wells Water may turn brackish or salty unfit for cultivation www.icsehelpline101.wordpress.com Compiled by Michelle Sequeira and Pranav Yadav TUBE WELLS: Advantages: Can irrigate larger area of land 400 hectares at a time Least evaporation No problem of brackish water Disadvantages: Costly Requires electricity Places: UP, Bihar, Gujarat CANALS: 2 types Inundation & Perennial INUNDATION Bed is higher than river bed Drawn directly from river Have water only during floods Mostly done by individual farmers cheaper PERENNIAL Bed is lower than river bed Drawn by making dams, barrages, weirs Have water throughout the year Mostly undertaken by govt costly Advantages: Gives water to fields during summer Save crop from drought Sediments add to fertility Cheap source of irrigation Initial expenditure is high cheap in the long run Disadvantages: May lead to water-logging along canal route due to seepage of water Excessive flow raises level of groundwater problem of reh Marshy areas nearby are breeding grounds for mosquitoes May overflow & cause floods during rainy season Can be practised in plain areas only Places: UP, Punjab, Haryana, Bihar www.icsehelpline101.wordpress.com Compiled by Michelle Sequeira and Pranav Yadav TANKS: partly dugouts/enclosing bunds Why in Peninsular India? Hard rocks make it difficult to dig canals and wells Limited percolation due to hard rock structure Rivers are seasonal cannot supply water to canals Advantages: Natural don t involve high cost Fishing in tanks provides food resources and adds to farmer s income Disadvantages: Dry up in summer Tanks may get silted regular desilting required Large surface area evaporation Occupies large space otherwise would have been used for cultivation Places: Peninsular India (Orissa, MH, KN, Kerala, W Bengal) FURROW: narrow channels of equal dimensions are made through every row of crops Advantages: Ensures even distribution of water Reduces flooding in fields More scientific Disadvantages: Takes time to construct Costlier Subjected to evaporation www.icsehelpline101.wordpress.com Compiled by Michelle Sequeira and Pranav Yadav SPRINKLER: comprises a long hose whose one end is joined to a water resource while the other end is joined to the sprinklers Advantages: Less wastage Ensures adequate amount of water Disadvantages: Costlier Can irrigate lesser area Subjected to evaporation DRIP: consists of a perforated pipe which is attached to the roots of the crops Advantages: Most efficient Least evaporation Least wastage Gives optimum amount of water Disadvantages: Very costly Can only be used for commercial farming Too much of humidity to crop may lead to plant diseases RAINWATER HARVESTING: technique of increasing the recharge of groundwater by storing rainwater locally. To meet increasing demand for water To raise underground water tables To reduce groundwater pollution To reduce soil erosion To supplement domestic water needs Places: Tamil Nadu, Meghalaya www.icsehelpline101.wordpress.com
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