Effect of 25 years old agroforestry practices on soil quality attributes in the north eastern Himalayan region of India

Long term effects of six agroforestry practices (AFPs) (>25 years old), on soil attributes with respect to soil degradation and improvement was assessed in the North Eastern Hill region of India and their effectiveness in improving soil health parameters was compared with shifting cultivation (Jhum) and natural forest of Khasi pine and terraced agriculture (Maize). Agroforestry practices significantly improved the soil physical, chemical and biological properties such as soil aggregation, water holding capacity, erosion susceptibility, soil organic carbon, microbial biomass carbon, basal respiration etc. The improvement was more pronounced in alder based agro forestry practices. Soil quality index (SQI) was also highest for Alder +large cardamom (0.858) followed by Alder +Tea +Black pepper (0.758) and Alder +Ginger (0.756). The study inferred that alder based agro forestry practices not only prevented from land degradation but improved the soil health and environmental sustainability. When shifting cultivation is unavoidable, the land restoration should be done with the help of alder based agro forestry practices to sustain its production and ecological functions.