Agroclimatic classification for assessment of crop potential And its application to dry farming tract of India

Abstract

To find out agroclimatic potential of a region, it is necessary to classify it into different agroclimatic zones. In this paper, a theory has been developed for agroclimatic classification on the basis of an index called 'Moisture Availability Index (MAI)’, which is defined as the ratio of assured rainfall to potential evapotranspiration. Three improvements have been made on earlier classifications. First, moisture availability index has been taken on weekly basis; second, minimum assured rainfall has been considered at different probability levels, and third, the different values of MAI and their duration have been taken as appropriate to various crop phases. The classification, however, has been recommended on the basis of moisture availability index at 50% probability level, which is considered to be an optimum value. The main classification has been further sub-divided depending upon the  length of water stress period.

The theory so developed has been applied first to the dry farming tract of India and then to Maharashtra.