Salt-affected soils in India and their management

Excess salts reduce the productivity of an estimated 7x106 hectares of otherwise productive soils. Of these, nearly 2.5x106 hectares are spread in the Indo-Gangetic plains, and are characterized by the presence of measurable quantities of sodium carbonate which impart to these soils a high exchangeable sodium percentage (ESP) and a high pH. These, in turn, cause the physical properties to deteriorate. A high pH also influences the availability and transformation of several plant nutrients and affects other physico-chemical phenomena independent of high ESP. Together these factors are responsible for the unproductivity of these soils. Apart from losses in crop production, alkali soil areas cause large runoffs which are hazardous for areas downstream. The paper summarizes research efforts to develop appropriate technologies for reclaiming and managing alkali soils