Suchergebnisse

Himalayan regions have increasing sediment yield due to undulating topography, slope and improper watershed management. However, due to limited observation data, and site accessibility issues, less studies have quantiBed sedimentation loads in the Himalayas, especially Nepal. This has hindered the investments on run-of-river hydropower projects as high and unpredicted sedimentation has increased losses in hydropower production. Therefore, there is a need to understand key physical processes driving sedimentation in these regions, with the available data. This study used the Soil and Water Assessment Tool (SWAT) to estimate the sedimentation yields in the Kaligandaki basin of Nepal, which is an important tributary that drains into the Ganges. Multi-source data from Beld observations, remote sensing platforms, surveys and government records were used to set up and run the SWAT model for the Kaligandaki basin from 2000 to 2009. Results for the 10-year model run indicate that 73% of the total sediment load is estimated to come from the upstream regions (also known as High Himalayan region), while only 27% is contributed from the Middle and High Mountain regions (where land managementbased interventions were deemed most feasible for future scenarios). The average sediment concentration was 1986 mg/kg (ppm), with values of 8432 and 12 mg/kg (ppm) for maximum and minimum, respectively. Such high sedimentation rates can impact river ecosystems (due to siltation), ecosystem services and hydropower generation. In addition, model results indicate the need for better high frequency observation data. Results from this study can aid in better watershed management, which is aimed at reducing sedimentation load and protecting Himalayan rivers.

As the demand for fresh water has increased over the years, the conflicts between water-sharing countries have also been on the rise. Many countries, such as Bangladesh in Asia, depend upon water originating from outside their national borders and hence do not have any control in the headwaters and large part of the watershed management of their rivers. Being militarily and economically weaker than its neighbours, it cannot influence their watershed management policies. Consequently, it suffers from both floods and water scarcity. This paper looks at the long-standing conflict between Bangladesh and India with regard to the sharing of water of the River Ganges. It discusses the water quantity and quality problems faced by Bangladesh and its inability to negotiate an equitable deal with India. In order to reduce the water-sharing conflict between Bangladesh and India, a multi-national watershed management approach is required.

The increasing demand for water, energy and food, and the interdependence of these systems could lead to potential human conflict in the future. This was seen in the food crisis of 2008, which stirred a renewed interest in taking a "systems" approach to managing resources. The initial flurry of activities led to many nexus frameworks, but there remains a gap between theory and its implementation. This paper tries to look at various frameworks and unpacks the concept of nexus in order to develop matrices to help quantify and understand the interlinkages between the nexus systems. It suggests multi-level and multi-system indices to measure the health of nexus systems and to identify the weak links. It is hoped that such frameworks can be used at country level, and eventually be used to measure and rank countries on the health of their systems. The paper suggests a questionnaire that can be used (after modifying for local conditions) to collect country-level institutional and political-economy data (which is difficult to get from online resources) to be used in the framework.