Chemistry and Fertility - Management of Humid Tropical Soils of Kerala as Influenced by Topography and Climate

摘要

The soils of Kerala - a state which can be visualized as a macro-watershed - developed by the pedogenic process of laterization, shows distinct variation due to the exclusive influence of climate, topography and vegetation. The imprint of marine sediments is depicted in the formation of coastal sandy and the acid sulphate/ saline soils. The midland laterites extending along the length of the state occupy a major share of the uplands. Acidity is the single most important factor to be managed in terms of fertility. Maintenance of organic carbon status is another important task to be handled. Magnesium, boron and calcium are the most critical nutrients in fertility management hindering maximum productivity. The dominant forms of these nutrients contributing to bioavailability and the strategies for fertility management are also discussed.