Assessment of shifting cultivation fallows in Northeastern India using Landsat imageries

Shifting cultivation ( Jhum ) has been a threat to the rich biodiversity of Northeastern India (NEI). Here, we applied an integrated spectral enhancement technique to map the shifting cultivation fallow/ current jhum area in NEI for 2014, 2016 and 2018 using Landsat-8 data. The natural vegetation in shifting cultivation fallow land was analyzed through field sampling. Manipur state occupied the highest shifting cultivation fallow area of 1528.5 km 2 (2014), and it was minimum in Tripura state with 178.3 km 2 (2018). The shifting cultivation fallow hotspot map was derived to identify the repetitive patches, in which the state of Arunachal Pradesh topped with 24.9% and Tripura with lowest 3.6%. Field sampling revealed dominance of four invasive species viz., Mikania micrantha, Ageratum houstonianum, Chromolaena odorata and Ageratina adenophora. We provided an insight into shifting cultivation fallow dynamics and vegetation composition in less than 3 year old shifting cultivation fallow lands. The study using remote sensing approach revealed that the fragile ecosystems of NEI are still facing the threat from shifting cultivation, though the trend has started declining. The generated database can be regularly updated in future using recent Sentinel-2 data with higher spatial and temporal resolution that would enhance the quality of land use management plans.