Twelve hydropower schemes have been proposed for the Lao, Lao-Thai and Cambodian reaches of the Mekong mainstream. Implementation of any or all of the proposed mainstream projects in the Lower Mekong Basin (LMB) could have profound and wide-ranging socio-economic and environmental impacts in all four riparian countries.
This consultation is a contribution to an assessment of the impacts of basin development on fish production in the Lower Mekong Basin (LMB). Fish of different species respond to development activities, in particular hydropower development, in different ways depending upon their migratory behaviour and their ability to adapt to and tolerate new environmental conditions.
Cambodia is highly vulnerable to the effects of climate change on fisheries, which supply livelihoods for millions and up to 80% of all animal protein in the diet. Most fisheries are highly variable by nature and subject to environmental change, including climate change. Hydropower dam construction, intensified fishing pressure and macroeconomic drivers are likely to affect Cambodian fisheries more immediately and visibly than climate change.
Fishpen culture is a possible means to increase fish production in Casamance, Senegal and to develop aquaculture without negative environmental effects. To study this possibility, a fishpen study was conducted in two dammed valleys, Guidir and Balobar in the area. Wild Sarotherodon melanotheron from 7.7 to 25.4 g and Tilapia guineensis from 7.7 to 35.0 g were stocked at densities ranging from 1.5 to 2.5 individuals/ super(m). Results are summarized in this article.
In the absence of reliable data on the species composition of the catch in the Lower Mekong Basin, the authors look at three approaches to estimate the size of the region’s migratory fish resources.The article, based on three different studies, concludes that 700,000 tonnes to 1.6 million tonnes of migratory fish are at risk. These possible losses correspond to respectively five times the size of the fishery sector in Finland and the whole fishery sector in Denmark.
The catch-effort relationship of the River Nile is Complicated by such factors as changes in water level and hydrology as well as spawning movements of the fish, which result in uneven distribution of the fish and fishing. The effects ofdam construction on the ecology of the fish fauna are considered, with particular reference to the effects of the Faraskour dam on the river fishery.
Wind and water power have a significant contribution to make to aquaculture and fish processing. Wind energy can provide mechanical power to operate pumps and aerators and can clso be used to generate electricity. Small-scalehydropower may be used to serve aquaculture in many ways wherever there is sufficient flow and fall of water. Additionally, refrigeration equipment and heat pumps may be driven by both wind and water power. The integration of these systems can serve energy needs in fish farming for processing, ice-making, mechanical power and electricity.
Freshwater allocation in an environment of increasing demand and declining quality and availability is a major societal challenge. While biodiversity and the needs of local communities are often in congruence, the over-riding necessity of meeting national demands for power, food and, increasingly, mitigation of the hydrological effects of climate change, often supersedes these.
In this paper, we assess how resettlement and changes in water access have altered livelihoods of local communities upstream of the Theun Hinboun Expansion Project in Lao PDR. Based on household surveys conducted both before and after resettlement, we estimate changes in water use and benefits among households of 4 resettled villages.
Most small waterbodies were built for irrigation and/or drinking water storage for humans and livestock, but have also been shown to play an important role in watershed management. Apart from natural lakes, small waterbodies are generally of two types: 1) reservoirs created by damming a river and, 2) ponds built on watersheds to collect and store surface runoff. There are millions of small waterbodies scattered throughout the world, most of which are poorly or not at all managed for fish production.