Trading-off fish biodiversity, food security, and hydropower in the Mekong River Basin

The Mekong River Basin, site of the biggest inland fishery in the world, is undergoing massive hydropower development. Planned dams will block critical fish migration routes between the river's downstream floodplains and upstream tributaries. Here we estimate fish biomass and biodiversity losses in numerous damming scenarios using a simple ecological model of fish migration. Our framework allows detailing trade-offs between dam locations, power production, and impacts on fish resources.

The importance of the fish resource in the Mekong River and examples of best practices

The Mekong is an exceptional river in many ways. In terms of fish biodiversity, it is the world’s second richest river after the Amazon (www.fishbase. org). With 6 to 18% of the global freshwater fish catch, it is also home to the largest freshwater fisheries in the world. The productive Mekong fisheries are essential to the food security of the 60 million people of the Lower Mekong Basin. Fish contributes 81% of the population’s protein intake in Cambodia and 48% in Laos. Mekong inland fisheries also provide employment to 1.6 of the 14 million Cambodians.

Fish, sediment and dams in the Mekong

The Mekong River is home to the largest inland fishery in the world, which is due in part to its exceptional sediment and nutrient loads. The number of dams in the Basin is expected to increase from 16 in the year 2000 to between 77 and 136 by 2030. These dams retain and accumulate sediments and nutrients in their reservoirs; as such, planned dam development is expected to result in a 60% to 96% reduction in sediment flow to downstream Mekong waters.

Balancing hydropower and biodiversity in the Amazon, Congo, and Mekong

The world's most biodiverse river basins (the Amazon, Congo, and Mekong) are experiencing an unprecedented boom in construction of hydropower dams. These projects address important energy needs, but advocates often overestimate economic benefits and underestimate far-reaching effects on biodiversity and critically important fisheries. Powerful new analytical tools and high-resolution environmental data can clarify trade-offs between engineering and environmental goals and can enable governments and funding institutions to compare alternative sites for dam building.

Heavy metal contamination in surface water and sediment of the Meghna River, Bangladesh

The present study was designed to evaluate the temporal variation of ten metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in the surface water and sediments of the Meghna River, Bangladesh during rainy, winter and pre-monsoon seasons by generating some baseline information on metal pollution in these proposed areas.

Unconventional fishing methods in the Anambra and Imo River Basins, Nigeria

The Anambra and Imo River basins are richly endowed with fishery resources. The use of unconventional fishing methods, such as local poisonous herbs and chemicals and various explosives, threatens to destroy their aquatic resources. Some control measures to be taken are suggested in the following areas: education, patrols, cooperatives and legislation.

Impact of tannery effluents on the aquatic environment of the Buriganga River in Dhaka, Bangladesh

This study presents an overview of the existence and effects of six heavy metals, chromium (Cr), lead (Pb), cadmium (Cd), mercury (Hg), manganese (Mn), and aluminum (Al), in tannery effluents released to the Buriganga River in Dhaka, Bangladesh. The pollutants were found in three different sources, such as effluents from tanneries, contaminated river water and three species of fish: climbing perch (Anabas testudineus), spotted snakehead (Channa punctata), and Black tilapia (Oreochromis mossambicus) caught from the river.

Variation of fish catch composition in relation to different types of 'katha' materials in the Updakhali river of Netrokona district, Bangladesh

Three types of Fish Aggregating Devices (FAD) locally known as "kathas" (sanctuary) with tree roots, bamboo roots and tree branches (traditional) and one additional control "katha" without any attracting materials were set up within 2 km area of Updakhali river in Netrokona district. The trial aimed to investigate the preference of fish to different "katha" materials.

Pages

Subscribe to RSS - River basins