Changing Ecological and Hydrological Conditions in the Himalayan Mountains and Measures of Future Adaptation

Abstract

The Himalayan mountains are one of the important geographical settings of the planet Earth for the source of global freshwaters. The freshwaters from the Himalayas are life supporting systems of the millions of people residing in downstream Asia. However, the high-altitude mountains of the Himalayas have gone through considerable transformations in hydrology and ecology over the recent past. In the 21st century, the hydrological flow regimes of glacial-fed rivers are threatened by both climate change and human disturbances. Rapidly changing temperature and the frequency, duration and timing of monsoonal precipitation have altered glacier melt, river flow, flood, and downstream volume of water. As a result, the ecosystems and biodiversity as well as irrigation-dependent agriculture in the region is profoundly impacted. The fundamental challenge today is therefore to address the issue of water resources through understanding of hydrological and ecological changes of lake and river systems in the region. Ecohydrology is a sustainability concept, which addresses water resource management through understanding of water cycle, including hydrological processes of rivers and lakes and the structure, and function of ecosystems. Putting ecohydrology at the center of the water resource management program, this mini review discusses rapid ecological and hydrological changes of freshwater systems in the Himalayan mountains and suggested some of the key future adaptation strategies of water resources to rapidly changing regional environment.

Environmental drivers dependent habitat expansion of introduced alien trout (Salmo trutta fario and Oncorhynchus mykiss) in the Himalayan ecosystem and management concerns in the time of climate change

“…Understanding the spatial behaviour of sh, and how they respond to environmental variation is critical to ensure their effective management, especially in the time of growing pressures such as climate change (Tewari et al, 2016), invasive species (Singh and Lakra, 2011;Singh, 2021) Despite the long history of trout in India, hardly any information exists on the ecology of the sh species under environmental drivers which may predict the success and limitation of its distribution and habitat expansion. The changing environmental parameters due to climate change or changing ecological conditions of the Himalayan aquatic ecosystem (Kattel, 2021) may form extended habitat for any introduced species in the space as a consequence of changes in environments. Ecological and environmental information are important for understanding spatial and temporal variability in distribution of any introduced alien sh species and also for providing the necessary feedback to guide policy options in the context of sh invasions which are recognized as the major threats to biodiversity (Singh & Lakra, 2011;Thapliyal et al, 2016;Araujo, et al, 2019;Hosegawa, 2020;Johal et al, 2021;Sharma et al, 2021;Singh, 2021).…”

“…Ecological and environmental information are important for understanding spatial and temporal variability in distribution of any introduced alien sh species and also for providing the necessary feedback to guide policy options in the context of sh invasions which are recognized as the major threats to biodiversity (Singh & Lakra, 2011;Thapliyal et al, 2016;Araujo, et al, 2019;Hosegawa, 2020;Johal et al, 2021;Sharma et al, 2021;Singh, 2021). Freshwater ecosystems in Himalaya present unique challenges to its sh diversity due to their linear spatial orientation and their association with upland habitat variables (Kattel, 2021).…”