Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800-4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape.
1 February 2021 in Journal of Applied Research on Medicinal and Aromatic Plants
As a basic component of the forest ecosystem, the forest structure refers to the general distribution of plant species of different life forms and sizes. The characterization of forest structure is the key to understanding the vegetation history, present status, and future development trajectory of the forest ecosystems. The Chure region of Nepal covers about 12.78% of the country’s land area and extends east to west along the southern foothills. This biologically rich but geologically fragile region is home to many species and provides many ecosystem services to millions of people. The Chure landscape is severely suffered from anthropogenic disturbances including logging, grazing, fuelwood collection, solid waste disposal, encroachment, forest fire, and excavation of sand, gravel, and boulders. In this study, we aim to characterize the forest ecosystem types outside the protected areas in the Chure region of Nepal and analyze the threat and vulnerability of the landscape from the biodiversity point of view. We sampled 62 sites to study the dominant vegetation type, regeneration status, and major threats to the forest ecosystems. A distribution map of the forest ecosystem types in Chure was prepared. We identified 14 forest ecosystem types in Chure including seven new ones. The newly reported forest ecosystems are Hymenodictyon excelsum Forest, Syzygium cumini Forest, Terminalia anogeissiana Forest, Schima wallichii–Shorea robusta Forest, Pinus roxburghii–Shorea robusta Forest, Pinus roxburghii Forest, and Bamboo thickets. We conclude that intensified human activities including forest encroachment and deforestation are mainly responsible for the ecological imbalance in the Chure region. We emphasize an in-depth analysis of biophysical linkage and immediate conservation efforts for the restoration of the Chure landscape in Nepal.