Suchergebnisse

Lake Kitangiri in Singida, Tanzania is facing enormous pressure as a result of overfishing, illegal fishing, and environmental degradation. The increase in population and climate change have caused a shift from dependency on economic activities such as crop cultivation and livestock keeping to fishing. The limited fish resources are over utilized and have been depleted due to increased fishing activities. In order to determine trends of fish production at Lake Kitangiri and the associated effects of overexploitation, a study was carriedout. Data were collected using household questionnaires, focus group discussion and key informants interviews. fish production, output of farming activities in Lake Kitangiri were found to have been decreasing over years. More importanly, fishing activities in the area have intensified due to influx of people to the area. Illegal fishing activities at the habitat for fish breeding have led to the depletion of fish in the lake. The findings suggest that the depletion of fishery resources has negative effects to the income of the households surrounding the Lake. The government has been trying to combat illegal fishing activities without involving the community or the community based organizations. It is therefore recommended that the government should involve the community in the conservation of the resoures. The introduction of high value crops in the area will reduce the number of people that look at fishing as the only viable livelihood activity thereby reducing pressure to the lake. It is also recommended that aquaculture be introduced to the area.

The Guadalentín basin is located in South East Spain; the climate is semiarid, being one of the driest areas of Europe, with high inter-annual variability in rainfall and constant aridity. Under these conditions, water becomes a key factor. Socioeconomic and natural systems have strong links that interact and influence each other. The way in which socioeconomic systems have evolved has been closely related to environmental factors, but also in response to political and technological changes. Land use historical changes are related with climate and the exploitation of water resources. The model proposed has three submodels: socioeconomic, groundwater, and surface water. Such submodels are connected by demand (use of water) and supply (water resources). Water supply is modelled in groundwater and surface water submodels; water demand in the socioeconomic submodel. A DSS (Decision Support System) application has been developed to make it easier to manage the model. Qualitative and quantitative indicators are used to reflect the dynamic behaviour of significant magnitudes such as soil quality and depth, population, employment, rural incomes, water quality and quantity (groundwater and surface water) and water consumption. ; This work is part of the Project "Procedimiento de Alerta y Seguimiento de la Desertificación en España", REN2000-1507-CO3-01 y 03/GLO, funded by CICYT. We are grateful for that funding. ; Peer reviewed

Enthält Rezensionen u.a. von: Le principe de précaution : aspects de droit international et communautaire / ed. by C. Leben. - Paris : Pantheon, 2002. - ISBN: 2-913397-21-2

The Chinese giant salamander (Andrias davidianus; CGS), endemic to China and Critically Endangered, has been identified as the amphibian species most in need of conservation action1. Since 2004, a rapidly growing industry to farm CGS for food, subsidised in order to diversify and bolster the rural economy and employment opportunities, has developed throughout much of China, centred on Shaanxi Province. By mid-2012 at least 141 CGS farms had been licensed in the province, with many more farms unrecorded. In 2011, 2.6 million farmed CGS were documented in Shaanxi Province alone. Wild-caught CGS continue to be in demand for breeding farms even though their capture is illegal. This is partly due to problems in getting > F1 animals to breed and partly due to huge (up to 100%) losses of farm stock from disease epidemics and the consequent requirement to restock affected farms2. This demand for breeding stock, which can command very high prices, has driven recent overexploitation and near-depletion from the wild. We visited CGS farms during outbreaks of fatal disease and, using PCR, we identified Ranavirus infection as the cause2. Thirty-nine of 43 additional farms surveyed reported that they had suffered disease outbreaks consistent with ranaviral disease. Three of the four farms that did not report disease held stock of ≤ 3,000 animals, lower than the mean number of 8,354 CGS per surveyed farm. The industrial-scale farming, high stocking densities, and trade in animals across China in the absence of biosecurity measures has led to a system that has fostered the propagation and spread of infectious disease. Genetic screening of wild and farmed CGS has identified geographic structuring of wild salamanders but genetic mixing and hybridisation of farmed animals3. The current structure and management of the CGS farming industry presents conservation threats to extant wild CGS (and possibly other wild fauna) through the discharge of contaminated farm wastewater or the escape of infected individuals to the wild. Additional disease and genetic threats to CGS conservation are posed by the Chinese government-sponsored conservation action of purchasing farmed animals for release into the wild without adherence to IUCN guidelines, such as pathogen or genetic screening, identification of suitable habitat or post-release monitoring. Complete separation of farmed and wild CGS populations and improved CGS farm management, including the quarantining of new stock and the disinfection of waste-water, is recommended in order to reduce disease risks to both farmed and wild animals. The number and native locations of CGS evolutionary significant units should be identified and in situ protection measures put in place and enforced. A CGS conservation action plan should be developed and, if conservation breeding and release is an identified requirement, this should be conducted separately from commercial farming and should follow IUCN guidelines. References 1. Isaac, N.J.B., Redding, D.W., Meredith, H.M.R. & Safi, K. (2012) Phylogenetically-informed priorities for amphibian conservation. PLoS ONE 7, e43912. 2. Cunningham, A. A., Turvey, S. T., Zhou, F., Meredith, H., Guan, W., Liu, X., Sun, C., Wang, Z. & Wu, M. (2016) The development of the Chinese giant salamander (Andrias davidianus) farming industry in Shaanxi Province, China: conservation threats and opportunities. Oryx 50, 265-273. 3. Yan, F., Lü, J., Zhang, B., Yuan, Z., Huang, S., Wei, G., Mi, X., Zou, D., Chen, S., Wu, M., Xiao, H., Liang, Z., Tapley, B., Papenfuss, T. J., Cunningham, A. A., Murphy, R. W., Zhang, Y. & Che, J. The Chinese giant salamander exemplifies the hidden extinction of cryptic species. Submitted. ; peerReviewed

This article shows how geo-legal devices created to deal with environmental crisis situations make access to drinking water precarious and contribute to the overexploitation and contamination of water resources. It relies on qualitative methods (interviews, observations, archive work) to identify and analyse two geo-legal devices applied in the case study of the Elqui Valley in Chile. The first device, generated by the Declaration of Water Scarcity, allows private sanitation companies to concentrate water rights and extend their supply network, thus producing an overexploitation of water resources. In the context of mining pollution, the second device is structured around the implementation of the Rural Drinking Water Programme and the distribution of water by tankers, which has made access to drinking water more precarious for the population and does nothing to prevent pollution.