CENTURY ecosystem model application for quantifying vegetation dynamics in shifting cultivation areas: A case study from Rampa Forests, Eastern Ghats (India)

Abstract

In India, slash and burn agriculture is one of the major factors contributing to deforestation, especially in the hilly north‐eastern region and Eastern Ghats. Studies on vegetation dynamics associated with slash and burn agricultural practices have been intensively studied in the north‐eastern part of India. These have covered semi‐evergreen/evergreen vegetation, but similar studies on tropical mixed dry deciduous ecosystems are not as common. In the present study, we used the CENTURY ecosystem model to study vegetation dynamics in shifting cultivation areas on the mixed dry deciduous forests covering the Eastern Ghats of India. The site‐specific parameters, temperature, precipitation, biomass and nutrient pools were used, and, by collecting information from local management practices, a 12‐year shifting cultivation cycle during a 70‐year period from 1960 to 2030 was simulated. CENTURY estimated a total loss of 239 tonnes carbon (tC) in soil organic matter over the simulation period, and the total nitrogen content of the soil organic matter showed an initial increase followed by a decline (344.3 g m2 during 1960 to less than 318.3 g m2 during 2030). CENTURY estimated that 66 tC ha−1 would be lost from the forest system, reducing the initial forest system carbon level from 118.5 tC ha−1. An increase in productivity from 0.49 tC ha−1 during 1960 to 1.2 tC ha−1 during the initial forest slash and burn in 1962 was observed, but thereafter productivity declined to 0.7 tC ha−1 during the year 2030. Results obtained in other studies of similar types of agricultural practices are also reviewed.