Management of Soil Fertility and Crop Productivity Under Shifting Agriculture in Mizoram, North-East India: Ways Forward

Shifting agriculture, a traditional cultivation system, has been practiced in North-east India for centuries by the majority of the hill farming communities for their subsistence. Previously, this system of cultivation, with sufficiently prolonged fallow periods (i.e. about 20–30 years), was often remarkably productive and ecologically balanced. However, shortened fallow periods in recent times have become a common practice because of expanding populations, shrinking area for cultivation, and increased demand for food. Shorter fallow periods do not allow the soil to restore adequate fertility to support sufficient crop growth, leading to widespread concerns about ecological sustainability. This chapter aims to explore options to improve the efficiency of shifting cultivation systems of Mizoram state in North-east India by applying the principles of soil fertility management in natural ecosystems. This approach integrates ecological processes that support high productivity under mixed cropping by utilising diverse species niches and including different practical alternatives to improve shifting cultivation. For example, practicing inter-row cropping between contour hedgerows of nitrogen-fixing shrubs like Flemingia macrophyla and Tephrosia candida, promoting terrace cultivation on slopes, and use of anti-erosional plants for establishing agroforestry systems. Further application of innovative approaches such as amendment of litter from nearby forests, use of indigenous microbes as biofertilizers, and enhancement of fallow recovery rates would likely boost soil fertility and crop productivity in shifting cultivation. Based on our synthesis, we suggest promoting site-specific indigenous tree-based subsistence farming systems where shifting cultivation is the dominant land-use. These systems can utilise the resources in an appropriate manner due to their varied growth and nutrient acquisition strategies, thus promoting agro-ecosystem development and improving productivity, diversity, and resilience.