Suchergebnisse

Though springs are the primary source of water for communities in the mid-hills of Nepal, an in-depth scientific understanding of spring systems is missing, preventing the design of effective climate-resilient interventions for long-term sustainability of springs. This study marks the first attempt to combine environmental isotopes analysis with hydrometric and hydrogeological measurements to identify dominant recharge zones for springs in two mountainous catchments—Banlek and Shikarpur—in Far-Western Nepal. In total, 422 water samples collected from rainfall, springs and streams between March 2016 and March 2017 were analyzed for their isotopic composition (d18O and dD). Isotopic composition of rainwater shows seasonality, suggesting that different sources of water vapor cause rains in monsoon and in dry season. Rainfall responses of individual springs were used to identify connections to unconfined and deeper groundwater strata. The isotopic composition of springs in the two catchments ranges from -9.55 to -8.06‰ for d18O and -67.58 to -53.51‰ for dD. The isotopic signature of the spring sources falls close to the local meteoric water line for the corresponding season, indicating strong rainfall contribution to springs. Altitudinal isotopic gradients suggest mean recharge elevation of 2,600–2,700 m asl for springs in Shikarpur, which lies beyond the surface-water catchment, and a recharge elevation of 1,000–1,100 m asl for Banlek, which partially extends beyond the surface-water catchment. The demarcated recharge zones will be used by government agencies to implement recharge interventions to increase the resiliency and reliability of springs in Far-Western Nepal.

Though springs are the primary source of water for communities in the mid-hills of Nepal, an in-depth scientific understanding of spring systems is missing, preventing the design of effective climate-resilient interventions for long-term sustainability of springs. This study marks the first attempt to combine environmental isotopes analysis with hydrometric and hydrogeological measurements to identify dominant recharge zones for springs in two mountainous catchments—Banlek and Shikarpur—in Far-Western Nepal. In total, 422 water samples collected from rainfall, springs and streams between March 2016 and March 2017 were analyzed for their isotopic composition (δ18O and δD). Isotopic composition of rainwater shows seasonality, suggesting that different sources of water vapor cause rains in monsoon and in dry season. Rainfall responses of individual springs were used to identify connections to unconfined and deeper groundwater strata. The isotopic composition of springs in the two catchments ranges from −9.55 to −8.06‰ for δ18O and −67.58 to −53.51‰ for δD. The isotopic signature of the spring sources falls close to the local meteoric water line for the corresponding season, indicating strong rainfall contribution to springs. Altitudinal isotopic gradients suggest mean recharge elevation of 2,600–2,700 m asl for springs in Shikarpur, which lies beyond the surface-water catchment, and a recharge elevation of 1,000–1,100 m asl for Banlek, which partially extends beyond the surface-water catchment. The demarcated recharge zones will be used by government agencies to implement recharge interventions to increase the resiliency and reliability of springs in Far-Western Nepal. ; Peer reviewed

Integrated adaptation strategies are needed to achieve the highly interlinked Sustainable Development Goals (SDGs) for water, food- and energy security in the Indus basin. However, detailed quantitative scenarios for the plausible dimensions of future resource security requirements under socio-economic development are lacking. Here we define three quantitative and spatially downscaled scenarios for future water, food and energy requirements in the Indus basin and we assess the implications of socio-economic development for the integrated resource security challenge. High-resolution gridded scenarios for resource security requirements are developed by combining three regionalised and spatialised Shared Socioeconomic Pathways (SSPs) with quantitative regional water, food and energy security thresholds. The results demonstrate that by 2080 basin level water- and energy security requirements are likely to at least double and potentially triple compared to the current situation. Food requirements could increase only marginally and double at most. Migration and urbanisation additionally drive the growing requirements to spatially converge around the largest cities of the basin. This demonstrates that socio-economic development increases the complexity of the water-food-energy security challenge by increasing its magnitude and spatial concentration. Future research and policymaking should anticipate for this heterogeneous growth of resource security challenges when developing adaptation strategies.

Integrated adaptation strategies are needed to achieve the highly interlinked Sustainable Development Goals (SDGs) for water, food- and energy security in the Indus basin. However, detailed quantitative scenarios for the plausible dimensions of future resource security requirements under socio-economic development are lacking. Here we define three quantitative and spatially downscaled scenarios for future water, food and energy requirements in the Indus basin and we assess the implications of socio-economic development for the integrated resource security challenge. High-resolution gridded scenarios for resource security requirements are developed by combining three regionalised and spatialised Shared Socioeconomic Pathways (SSPs) with quantitative regional water, food and energy security thresholds. The results demonstrate that by 2080 basin level water- and energy security requirements are likely to at least double and potentially triple compared to the current situation. Food requirements could increase only marginally and double at most. Migration and urbanisation additionally drive the growing requirements to spatially converge around the largest cities of the basin. This demonstrates that socio-economic development increases the complexity of the water-food-energy security challenge by increasing its magnitude and spatial concentration. Future research and policymaking should anticipate for this heterogeneous growth of resource security challenges when developing adaptation strategies.

This study was partially supported by core funds of ICIMOD contributed by the governments of Afghanistan, Australia, Austria, Bangladesh, Bhutan, China, India, Myanmar, Nepal, Norway, Pakistan, Sweden, and Switzerland. AO was supported by funding from the National Environmental Research Council (NERC) National Capability Overseas Development Assistance under the grant 'Polar expertise –Supporting development' (NE/R000107/1). ; River systems originating from the Upper Indus Basin (UIB) are dominated by runoff from snow and glacier melt and summer monsoonal rainfall. These water resources are highly stressed as huge populations of people living in this region depend on them, including for agriculture, domestic use, and energy production. Projections suggest that the UIB region will be affected by considerable (yet poorly quantified) changes to the seasonality and composition of runoff in the future, which are likely to have considerable impacts on these supplies. Given how directly and indirectly communities and ecosystems are dependent on these resources and the growing pressure on them due to ever-increasing demands, the impacts of climate change pose considerable adaptation challenges. The strong linkages between hydroclimate, cryosphere, water resources, and human activities within the UIB suggest that a multi- and inter-disciplinary research approach integrating the social and natural/environmental sciences is critical for successful adaptation to ongoing and future hydrological and climate change. Here we use a horizon scanning technique to identify the Top 100 questions related to the most pressing knowledge gaps and research priorities in social and natural sciences on climate change and water in the UIB. These questions are on the margins of current thinking and investigation and are clustered into 14 themes, covering three overarching topics of 'governance, policy, and sustainable solutions', 'socioeconomic processes and livelihoods', and 'integrated Earth System processes'. Raising awareness of these ...