Recovery of Soil Macronutrients Following Shifting Cultivation and Ethnopedology of the Adi Community in the Eastern Himalaya

Shifting cultivation involves a cycle of forest clearing, cultivation and a fallow phase. As the practice involves clearing forest, it is considered unsustainable and leads to soil fertility loss and erosion. While several variations of the practice exist, traditional communities undertake the practice systematically with relatively long fallow periods and are often knowledgeable about their landscape in terms of soil and its management. To better understand one such system, we quantified soil recovery following cultivation in terms of macronutrients and documented the traditional knowledge of the Adi community in a remote site in the Eastern Himalaya. We collected soil samples from three replicates, each from currently cultivated sites, uncut forest sites and successional sites 3, 12 and 25 yr following cultivation. Available nitrogen and phosphorus significantly increased, and there was an increasing trend in soil organic matter following cultivation. The Adi differentiated nine types of soil and preferred specific soil types for shifting and settled cultivation. We documented soil management and methods of soil fertility retention practised by the Adi. Their location of different crops in the field was based on the effect of the crop on soil fertility. Our research indicated that soil nutrient recovery was considerable following cultivation and that traditional shifting cultivators in the landscape were knowledgeable about their landscape in terms of soil diversity, undertaking practices to manage soil erosion and fertility. Future policies that will affect shifting cultivation in the region should acknowledge such systematic use of a landscape by traditional farming communities.