Distribution Pattern of Gymnosperms’ Richness in Nepal: Effect of Environmental Constrains along Elevational Gradients
Bikram Pandey,
Nirdesh Nepal,
Salina Tripathi,
Kaiwen Pan,
Mohammed A. Dakhil,
Arbindra Timilsina,
Meta F. Justine,
Saroj Koirala,
Kamal B. Nepali
Affiliations
Bikram Pandey
CAS Key Laboratory of Mountain Ecological Restoration and Bio-Resource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
Nirdesh Nepal
University of Chinese Academy of Sciences, Beijing 100049, China
Salina Tripathi
Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA
Kaiwen Pan
CAS Key Laboratory of Mountain Ecological Restoration and Bio-Resource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
Mohammed A. Dakhil
CAS Key Laboratory of Mountain Ecological Restoration and Bio-Resource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
Arbindra Timilsina
University of Chinese Academy of Sciences, Beijing 100049, China
Meta F. Justine
CAS Key Laboratory of Mountain Ecological Restoration and Bio-Resource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
Saroj Koirala
University of Chinese Academy of Sciences, Beijing 100049, China
Kamal B. Nepali
Ministry of Forest and Environment, Department of Plant Resources, National Botanical Garden, Godavari, Lalitpur 44709, Nepal
Understanding the pattern of species distribution and the underlying mechanism is essential for conservation planning. Several climatic variables determine the species diversity, and the dependency of species on climate motivates ecologists and bio-geographers to explain the richness patterns along with elevation and environmental correlates. We used interpolated elevational distribution data to examine the relative importance of climatic variables in determining the species richness pattern of 26 species of gymnosperms in the longest elevation gradients in the world. Thirteen environmental variables were divided into three predictors set representing each hypothesis model (energy-water, physical-tolerance, and climatic-seasonality); to explain the species richness pattern of gymnosperms along the elevational gradient. We performed generalized linear models and variation partitioning to evaluate the relevant role of environmental variables on species richness patterns. Our findings showed that the gymnosperms’ richness formed a hump-shaped distribution pattern. The individual effect of energy-water predictor set was identified as the primary determinant of species richness. While, the joint effects of energy-water and physical-tolerance predictors have explained highest variations in gymnosperm distribution. The multiple environmental indicators are essential drivers of species distribution and have direct implications in understanding the effect of climate change on the species richness pattern.
