Fragmented Forest Patches in the Indian Himalayas Preserve Unique Components of Biodiversity: Investigation of the Floristic Composition and Phytoclimate of the Unexplored Bani Valley

Abstract

Subtropical and temperate forests are amongst the most threatened habitats of Asia, due to large-scale habitat loss and the fragmentation of landscapes. Inspite of these, the Asiatic regions preserve their endemic biodiversity, and provide a favorable environment for the abundant growth of vegetation. In the Himalayas, many interior regions are still unexplored from a biodiversity perspective, due to remote locations and high snow-clad mountains. In this study, we investigated the unexplored Bani Valley in order to reduce the gap of uninventorized areas of rich biodiversity in the Himalayas and formulate plant conservation and management strategies. Thirteen field expedition tours were undertaken during 2017 and 2020 for data collection in different growing seasons in the study area. All plant species were collected as voucher samples, identified, and deposited in the internationally recognized Janaki Ammal Herbarium (acronym RRLH). GPS points were recorded in order to study the forest types and vegetation components of the study area. A total of 196 plant species belonging to 166 genera and 68 families were identified in Bani Valley, covering a total area of 2651 km2. Approximately 70.62% of the species were native and 29.38% were non-native. In total, 46% of species were Indo-Malayan, followed by 22% Palearctic species. In angiosperms, dicotyledon species (68.37%) dominated. Poales were the most dominant order, with 38 species (19.38%). The most abundant families were Poaceae with 29 species (14.79%), Fabaceae (17, 8.67%), Rosaceae, Cyperaceae, and Asteraceae (9, 4.59% each). The life form analysis showed 50% of species as phanerophytes, followed by therophytes (25.77%). The leaf size spectra show mesophyllous species (34.69%) as the dominant group. The IUCN Red List of Threatened Plants categorized Ailanthus altissima as endangered (EN), Aegle marmelos and Quercus oblongata as near threatened (NT), Ulmus wallichiana and Plantago lanceolata as vulnerable (VU), Taxus baccata and 75 other species as least concern (LC), and 2 species as data deficient (DD). The remaining 113 species of plants had not been evaluated according to the IUCN Red List of Threatened Species. This study will help to shape conservation and management plans for threatened species for future implementation, and will help in biodiversity conservation. This study will serve as a database for future reference materials in terms of biodiversity management.