干旱区生态环境知识资源中心

Water balance studies have been carried out to suggest different cropping plans either for an agroclimatic zone or at the most for a district for adoption at field (micro) level while the required data on rainfall and soils varies even within the district too. A water balance study was conducted at tehsil level in Bhilwara district of Rajasthan state which-reveals that normal annual rainfall varies from 441 to 743 mm and available water holding capacity of soils varies from 90 to 200 mm which leads to variability in climatic conditions from arid to semi arid among different tehsils of the target district. The study also revealed that length of rainy season varies from 10.7 to 12.3 weeks; water surplus varies from 43.2 to 241.6 mm and water deficit from 61.4 to 124.7 mm at tehsils level. The suggested cropping plan varies from intercropping of groundnut / maize +pigeon pea in one tehsil to sole sesame/ black gram in other tehsil. Thus, distinct crop planning is required at micro (tehsil) level for efficient utilization of natural resources under dryland regions.