Climate BT - The Soils of India

Abstract

Climate is one of the five soil-forming factors and has a significant influence on the properties of soil. India has a great geographic and geomorphologic diversity with a number of different climate regimes. We sow the seeds in soil, but grow the plants on land that also constitutes the climate. Agriculture depends on the mean climate of a particular region. Indian agriculture is primarily rain-fed, with a majority of farmers dependent on monsoon for irrigating their crops. Drought, floods, variation in onset dates, wet and dry spells further pose detrimental effects on agriculture. The chapter highlights the effects of climate on agriculture and summarizes the climate in various seasons in different parts of the country. This also covers the trends of various weather parameters over the years. The trends indicate that annual mean surface air temperatures have shown significant warming of about 0.63 °C/100 year during the past 115 years (1901–2015). Frequency of depressions and cyclonic storms formed over the north Indian Ocean (1951–2015) during the monsoon and post-monsoon seasons have shown decreasing trends. Through the effects of precipitation and temperature, climate affects the rates of biological, chemical and physical processes involved in soil formation. The development of soil profile and its physical and chemical composition are greatly affected by weather and also have a role in crop performance. The chapter also covers the impacts of climate change on soil quality, nutrient dynamics, organic matter turnover and soil erosion. Possible adaptation and mitigation approaches are highlighted. Opportunities for carbon sequestration as a tool to mitigate climate change have been pinpointed.