NATURAL RESOURCES • LAND • WATER • VEGETATION
LAND National Bureau of Soil Survey and Land Use and Planning(NBSS&LUP)
Geographical area of India 3287 lakh ha • Net cultivated area : 1420 lakh ha • Irrigated area : 570 lakh ha • Rainfed area : 850 lakh ha • Low productivity and low input usage are two major issues confronting rainfed farming. • Productivity per unit of land • Productivity per unit of water are important for optimum production.
RECLAMATION OF SALINE SOILS • Deep ploughing • Sanding • Adding gypsum • Adding sulfur • Adding organic matter • Causes : Low rainfall, high evaporation rate, poor drainage, irrigation with saline water • RECLAMATION OF ALKALINE SOILS • Application of gypsum, leaching, green manuring, straw mulching • Causes : presence of carbonates of ca, mg and na • RECLAMATION OF ACID SOILS: • Adding ground limestone (calcium carbonate) Causes : High rainfall
WATER • Blue water is the source of supply. It is equivalent to the natural water resources (surface and groundwater runoff). • Green water is the rainwater directly used and evaporated by non-irrigated agriculture, pastures and forests
VIRTUAL WATEER Amount of water that is embedded in food or other products needed for its production Trade in VW allows scarce countries to import high water consuming products while exporting low water consuming products 1 cup of coffee needs 140 litres of water 1 litre of milk needs 1000 litres of water. 1 kg of wheat needs 1350 litres of water. 1 kg of rice needs 3000 litres of water. 1 kg maize needs 900 litres of water.
WATERSHED • A geohydrological unit draining to a common point by a system of drains. • It is topographically delineated area draining into a single channel. • It is considered as a biological, physical , economic and social system • It is environmental tool for taking up development initiatives • It is a logical unit for planning optimal development of its soil, water and biomass resources.
TYPES OF WATERSHEDS • MACRO WATERSHED > 50000 ha • SUB WATERSHED > 10000 to 50000 ha • MILLI WATERSHED > 1000 to 10000 ha • MICRO WATERSHED > 100 to 1000 ha • MINI WATERSHED > 1 to 100 ha