Crop moisture index in characterizing the agricultural Drought at Hissar

Abstract

Due to non-availability of soil moisture measurements on large scale, the meteorological budgeting technique has been utilized informulating a crop moisture index in explaining the behaviour of agricultural droutht-its intensity, duration and severity for six different monsoon rainfall years at Hissar station. A thorough testing of Palmer Crop Moisture Index has also been made in explaining the behaviour of rainfall crops during the six monsoon years 1971-1976. Palmer crop moisture index fails to explain the behaviour of crop conditions in the area under study and thus necessitated the formulation of a new crop moisture index which explains the crop conditions in accordance with results obtained in the experimental plots under dryland agriculture.

The weekly crop moisture indices have been found better in depicting the crop conditions and can be successfully used in predicting the crop outlook over a large area. Also based on the crop moisture conditions various precautionary measures and agronomic practices have been indicated for practical use when the southwest monsoon is apparently difficult to predict because of the complex monsoon system. The agricultural drought has been classified as under based on the crop moisture index values during the growing season of the crop:

Crop moisture index               0-.33           .34-.75   .76-1      1.01-2    2.01-3     3.01-4            >4.01

Agricultural drought cat.      Extremely dry    dry       Semidry   normal   moist    wet Extremely  wet

The crop moisture index – its intensity, duration and rhythm in space and time have been found to be very helpful in explaining the role of agronomic practices and has potentiality to explain the crop yield variations.