Agrobiodiversity under Agroforestry Systems in Garhwal Himalayan Region: A Case Study

Agrobiodiversity refers to the variety and variability of all living organisms that form part of agricultural ecosystems. It encompasses crops, livestock breeds, soil organisms, pollinators, and wild relatives. The present investigation was conducted to assess agrobiodiversity in two agroforestry systems (Apple and Oak) across three districts (Tehri, Uttarakashi and Rudraprayag) of Uttarakhand, within two elevation ranges: 1500-2000 m and 2000–2500 m amsl. Data were collected through questionnaire surveys, field observations, and quadrat sampling. The results revealed that agrisilviculture, agrihorticulture, and silvipasture systems were present in all three districts at both elevations, except in the higher elevation zone of Uttarkashi district. Interestingly, a unique agroforestry system, aquaculture, was recorded only in Rudraprayag district at the upper elevation. In total, five crop categories were documented under apple- and oak-based agroforestry systems within the two elevation ranges. These included cereals and pulses (7 species), millets (2 species), oilseeds (3 species), and vegetables (28 species), with vegetables representing the highest diversity. Additionally, a total of 106 wild plant species were recorded across the study sites, comprising 49 herbs, 19 shrubs, 13 grasses, 4 vines, and 21 tree species across both agroforestry systems and elevation ranges in all three districts. Pollinator diversity was represented by five insect orders. The highest number of pollinators (11 species) belonged to Hymenoptera, followed by Diptera (6 species) and Lepidoptera (6 species), while the lowest diversity was observed in Hemiptera. Order-wise analysis indicated that Hymenoptera contributed the highest proportion of pollinators, whereas Hemiptera accounted for the least across all districts. Overall, the study highlights the rich agrobiodiversity within the agroforestry systems of Uttarakhand, with notable variations in crop composition, wild vegetation, and pollinator diversity across districts and elevation ranges.