Spatial patterns, underlying drivers and conservation priorities of orchids in the central Himalaya

Abstract

Understanding the primary drivers of species diversity patterns and identifying critical places for biodiversity protection are the two major concerns confronting the global conservation community. The Orchidaceae, which is one of the most diverse angiosperm families with over 30,000 species, is currently facing grave threats from habitat degradation, climate change, and a range of human-induced issues. However, the spatial patterns of orchid distribution and the factors influencing these patterns, both of which are crucial for developing successful orchid conservation plans, remain poorly understood. Here, using one of the most extensive distribution datasets of >500 orchid species in Nepal, we mapped the distribution of all, common, rare, epiphyte, and terrestrial species and identified important factors driving their patterns. We also assessed their protection gaps and identified key conservation regions. We discovered low spatial congruence between the diversity patterns of different groups, and the fundamental drivers underlying the richness pattern differed considerably. The key orchid conservation areas were primarily found in the mid-hills and highlands of central Nepal, with 62 % of these areas outside the protected area (PA) network. Our findings emphasize the importance of considering pollinator diversity and other climate factors when developing effective management plans to conserve orchids, as well as employing different strategies to conserve different life forms. A huge conservation gap in protecting orchids despite large PA coverage in Nepal indicates insufficiency of existing PA network in conserving plants. Therefore, our findings reiterates the need to consider plant conservation goals alongside animal conservation priorities in future conservation planning.