Quantitative Assessment of Floristic Diversity in Large Cardamom based Traditional Agroforestry System Across Altitudinal Gradient in Darjeeling Himalaya, India

The present study was carried out in Darjeeling Himalayas region of West Bengal, India from January, 2019 toApril, 2021. The study area was classified into three altitudinal class i.e., low, mid and high with eleven, nine and five holdings, respectively. The important value index (IVI) of the documented species at the studied systems varied from 0.15-17.11 irrespective of altitude classes. IVI estimated for large cardamom was 12.74 while, at low-, mid-and high-altitude class it was 9.41, 13.88 and 18.59 respectively. Overall, the most important species based on IVI was fern Selaginella denticulata followed by herb Amomum subulatum. The least important species based on IVI was a tree Litsea glutinosa (0.15). Based on the distribution of plant species in the system five species distribution models (SDM) were evaluated and the Preemption SDM give best fit to the data with highestAkaike Information Criterion (AIC) score.