Conclusions

Abstract

AbstractClimatic variability and the water-energy continuum have a significant influence on driving life-form richness in the Indian Himalayas. High potential evapotranspiration and moderate precipitation in Eastern Himalayas, and high potential evapotranspiration and precipitation of the driest quarter in Western Himalayas play crucial roles in the region’s life-form richness. While temperature seasonality and precipitation seasonality have a significant positive correlation on nondominant life-forms, for example, herb richness in the Eastern Himalaya and woody species richness in Western Himalaya, both climatic heterogeneity factors have negative impacts on the dominant life-forms. This suggests the potential negative impact of climatic perturbations on life-form richness, which is going to be critical for the Himalayan ecosystem going forward. The cation exchange capacity and soil organic carbon content characterize the life-form richness of tree-dominated eastern Himalayas, which explains the key role of soil in the root penetration of trees. The significant role of the terrain ruggedness index on woody species richness describes the significance of water retention of soil and the physical heterogeneity of the deep root system of woody species. Anthropogenic interventions are a common phenomenon, but impacts are substantially high in nondominant life forms suggesting accessibility and local demand for ecosystem services account for the sustenance of life forms. The Eastern Himalayas and Western Himalayas possess distinct physiography and climate gradient and therefore, they show differences in species composition and distribution of life forms. The increasing anthropogenic interferences in mountain ecosystems also have significant impacts on altering the species composition. The invasion of exotic species to these ecosystems and their superior adaptability to replace the native species of mountain systems is prominent in global climate change scenarios. The influences of climate, physiography, soil, and anthropogenic interventions on plant richness, and the comparison of woody and nonwoody species richness of the Eastern and Western Himalayas are no less complex.KeywordsWater-energy dynamics Climatic heterogeneity Models Richness Nonlinear Non-woody speciesPhysical heterogeneity