Quantitative assessment of crop species diversity in shifting cultivation system of Eastern Himalaya

摘要

The narrowing of diversity in crop species contributing to the world's food supplies has been considered a potential threat to food security. The present study quantifies crop species diversity in controversial shifting cultivation system (SCS) using primary data from 52 villages spread across six North-Eastern (NE) hill states of India. The findings reveal that SCS is much diversified compared to settled cultivation system. Along with cereals, millets and pulses, the upland tribes grow a variety of horticultural crops on SC land. At the aggregate level, horticultural crops in the sampled states were observed to be much diversified and the mean diversification index value was found to be 0.79 (Simpson's Diversity Index) for the six NE hill states on SC land. The present study documented 25 cultivars of vegetables, 22 cultivars of fruits, spices and plantation crops, and 12 field crops in SCS, besides many minor fruits and underutilized vegetables. However, the most densely populated crop species were rice, maize and finger millet in the case field crops. Vegetable crops included pumpkin, potato and ash gourd, and fruit crops included banana, pineapple and citrus, while spices like ginger, chilli and turmeric were densely cultivated on SC land. Thus, the prevailing crop species in SCS had their own attributes, performances and challenges. Experiences of the present study shall be the guiding benchmark for those who negate the possibilities of agrobiodiversity in SCS.