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More people, more food, worse water?: a global review of water pollution from agriculture Полный текст
2018
Mateo-Sagasta, Javier | Zadeh, S. M. | Turral, H.
Current patterns of agricultural expansion and intensification are bringing unprecedented environmental externalities, including impacts on water quality. While water pollution is slowly starting to receive the attention it deserves, the contribution of agriculture to this problem has not yet received sufficient consideration.We need a much better understanding of the causes and effects of agricultural water pollution as well as effective means to prevent and remedy the problem. In the existing literature, information on water pollution from agriculture is highly dispersed. This repost is a comprehensive review and covers different agricultural sectors (including crops, livestock and aquaculture), and examines the drivers of water pollution in these sectors as well as the resulting pressures and changes in water bodies, the associated impacts on human health and the environment, and the responses needed to prevent pollution and mitigate its risks.
Показать больше [+] Меньше [-]Basin perspectives on the Water–Energy–Food Security Nexus Полный текст
2013
Lawford, Richard | Bogárdi, János | Marx, Sina | Jain, Sharad | Pahl-Wostl, Claudia | Knüppe, Kathrin | Ringler, Claudia | Lansigan, Felino | Meza, Francisco
This article summarizes some major factors that influence the Water–Energy–Food (W–E–F) Security Nexus and how they are perceived in different basins. These findings are based on a survey that was undertaken for the Global Catchment Initiative (GCI) within the Global Water System Project (GWSP) complemented by case studies for a transboundary basin (the Lake Winnipeg Basin), a national basin (Yellow Basin in China), and a number of the basins in a nation (India). The analysis also includes ranking of river basin issues related to the WEF Nexus based on the views of experts in nine basins. Based on this analysis, factors that have affected the evolution of the W–E–F Nexus, including the applications of Earth observations, are discussed. The study concludes that the W–E–F Nexus could be an effective vehicle for advancing water and sustainability issues and recommends research and demonstration projects to test the extent to which the WEF framework could be helpful in increasing understanding and collaborative governance approaches.
Показать больше [+] Меньше [-]Global Distribution and Prevalence of Arcobacter in Food and Water Полный текст
2015
Hsu, T.‐T. D. | Lee, J.
The emerging foodborne and waterborne pathogen, Arcobacter, has been linked to various gastrointestinal diseases. Currently, 19 species are established or proposed; consequently, there has been an increase in the number of publications regarding Arcobacter since it was first introduced in 1991. To better understand the potential public health risks posed by Arcobacter, this review summarizes the current knowledge concerning the global distribution and the prevalence of Arcobacter in food and water. Arcobacter spp. were identified in food animals, food‐processing environments and a variety of foods, including vegetables, poultry, beef, dairy products, seafood, pork, lamb and rabbit. A wide range of waterbodies has been reported to be contaminated with Arcobacter spp., such as wastewater, seawater, lake and river water, drinking water, groundwater and recreational water. In addition, Arcobacter has also been isolated from pets, domestic birds, wildlife, zoo and farm animals. It is expected that advancements in molecular techniques will facilitate better detection worldwide and aid in understanding the pathogenicity of Arcobacter. However, more extensive and rigorous surveillance systems are needed to better understand the occurrence of Arcobacter in food and water in various regions of the world, as well as uncover other potential public health risks, that is antibiotic resistance and disinfection efficiency, to reduce the possibility of foodborne and waterborne infections.
Показать больше [+] Меньше [-]Food quality for Daphnia in humic and clear water lakes Полный текст
2007
GUTSEIT, KELLY | BERGLUND, OLOF | GRANÉLI, WILHELM
1. Growth and reproduction of Daphnia fed lake seston were measured in two categories of meso- to eutrophic lakes differing with respect to terrestrial organic matter influence (humic and clear water lakes). The content of highly unsaturated fatty acids (HUFA), P and N, as well as the taxonomical composition of seston were analysed. 2. Seston HUFA and C : P ratios were similar between lake categories, whereas C : N ratios were lower in the clear water lakes in both spring and summer. Despite the similarity in HUFA and P content of seston, Daphnia growth rate, clutch size and the proportion of gravid females were, respectively, about 1.5, 3 and 6 times higher in the clear water lakes. 3. Differences in growth and reproduction were related to a combination of higher N content and good fatty acid quality of the seston in the clear water lakes. Relatively high biomass of edible algae, such as Rhodomonas sp. and Cryptomonas sp., in the clear water lakes, and differences in water pH likely contributed to the observed differences in Daphnia growth and reproduction between lake categories. Additionally, it is possible that Daphnia was energy limited in the humic lakes despite high particulate organic carbon (POC) concentrations, as the contribution of non-algal and detrital C to the POC pool was high. 4. Our results suggest that dietary HUFA content has the potential to improve herbivore growth and reproduction if N and P are not limiting. N merits more attention in studies of zooplankton nutrition.
Показать больше [+] Меньше [-]Climate variability affects water-energy-food infrastructure performance in East Africa Полный текст
2021
Siderius, Christian | Kolusu, Seshagiri R. | Todd, Martin C. | Bhave, Ajay | Dougill, Andy J. | Reason, Chris J.C. | Mkwambisi, David D. | Kashaigili, Japhet J. | Pardoe, Joanna | Harou, Julien J. | Vincent, Katharine | Hart, Neil C.G. | James, Rachel | Washington, Richard | Geressu, Robel T. | Conway, Declan
The need to assess major infrastructure performance under a changing climate is widely recognized yet rarely practiced, particularly in rapidly growing African economies. Here, we consider high-stakes investments across the water, energy, and food sectors for two major river basins in a climate transition zone in Africa. We integrate detailed interpretation of observed and modeled climate-system behavior with hydrological modeling and decision-relevant performance metrics. For the Rufiji River in Tanzania, projected risks for the mid-21ˢᵗ century are similar to those of the present day, but for the Lake Malawi-Shire River, future risk exceeds that experienced during the 20ᵗʰ century. In both basins a repeat of an early-20ᵗʰ century multi-year drought would challenge the viability of proposed infrastructure. A long view, which emphasizes past and future changes in variability, set within a broader context of climate-information interpretation and decision making, is crucial for screening the risk to infrastructure.
Показать больше [+] Меньше [-]Valuing of Wadi El-Rayan ecosystem through water–food–energy nexus approach Полный текст
2017
AbdelHady, Rameen S. | Fahmy, Hussam S. | Pacini, Nic
Wadi El-Rayan Protected Area (WERPA) is considered a model protectorate and an ecological restoration success. Development and mismanagement of Wadi El-Rayan vulnerable water resources could lead to the depletion of two artificial lakes and large scale deterioration of ecosystem health. We quantify the environmental value of preserving WERPA by applying the water–food–energy nexus approach and the concept of non-monetary opportunity cost. Three output indicators: agriculture, aquaculture and net energy production are selected to assess the value of different ecosystem health conditions under three water management scenarios. STELLA object oriented modeling environment has been used to simulate the scenarios that led to favorable, satisfactory, and critical ecosystem health conditions. The results demonstrated that the economic output that could be realized by reaching the favorable condition has twice the value of the acceptable condition.
Показать больше [+] Меньше [-]Surface water connectivity controls fish food web structure and complexity across local- and meta-food webs in Arctic Coastal Plain lakes Полный текст
2019
Laske, Sarah M. | Rosenberger, Amanda E. | Wipfli, Mark S. | Zimmerman, Christian E.
The need for theories that address food web assembly and complexity over multiple spatial scales are critical to understanding their stability and persistence. In a meta-food web – an integrated network of local food webs – spatial heterogeneity in physical processes may have profound effects on food web function and energy flow. In the Arctic, surface water connectivity plays a vital role in determining fish assemblage composition, and potentially, food web structure. We examined lentic food web complexity associated with heterogeneity in surface water connectivity among Arctic lakes at the local scale, by contrasting lakes over a stream-lake connectivity gradient, and at the regional scale, by contrasting two locations with different surface water conditions (i.e., wet and dry) on the Arctic Coastal Plain of Alaska. Among lakes and across locations, increased hydrologic connectivity between streams and lakes increased the number of fish species and increased the complexity of the food web. The interaction of the region's hydrologic connectivity, local stream-lake connections, and the trophic niches of relevant fish species produced integrated, complex meta-food webs. Fully understanding mechanisms that support meta-food web stability are crucial when assessing future changes to Arctic stream-lake networks and the function and persistence of aquatic food webs.
Показать больше [+] Меньше [-]Food habits of great cormorant Phalacrocorax carbo hanedae in the Isumi river's water system [Japan] and the Yoro river's water system
2007
Ai, K.(Chiba-ken. Fisheries Research Center, Chikura (Japan)) | Ozaki, M.
Daphnia Magna Fitness During Low Food Supply Under Different Water Temperature and Brownification Scenarios Полный текст
2016
GALL, Andrea | Kainz, Martin J. | RASCONI, Serena
Much of our current knowledge about non-limiting dietary carbon supply for herbivorous zooplankton is based on experimental evidence and typically conducted at ~1 mg C L–¹ and ~20°C. Here we ask how low supply of dietary carbon affects somatic growth, reproduction, and survival of Daphnia magna and test effects of higher water temperature (+3°C relative to ambient) and brownification (3X higher than natural water color; both predicted effects of climate change) during fall cooling. We predicted that even at very low carbon supply (~5µg C L–¹), higher water temperature and brownification will allow D. magna to increase its fitness. Neonates (<24 h old) were incubated with lake seston for 4 weeks (October-November 2013) in experimental bottles submerged in outdoor mesocosms to explore effects of warmer and darker water. Higher temperature and brownification did not significantly affect food quality, as assessed by its fatty acid composition. Daphnia exposed to both increased temperature and brownification had highest somatic growth and were the only that reproduced, and higher temperature caused the highest Daphnia survival success. These results suggest that even under low temperature and thus lower physiological activity, low food quantity is more important than its quality for D. magna fitness.
Показать больше [+] Меньше [-]Potential influence of water level changes on energy flows in a lake food web Полный текст
2011
Wang, YuYu | Yu, XiuBo | Li, Wenhua | Xu, Jun | Chen, YuWei | Fan, Na
Large seasonal water-level fluctuations may influence isotopic signatures of primary producers and the types and amounts of these potential food sources accessible to aquatic fauna of Poyang Lake, the largest freshwater lake in China. In this study, the isotopic signatures of primary producers and consumers were determined, stable carbon and nitrogen isotope analysis and mixing models were combined to investigate the influence of water levels on the diet and isotopic composition of Poyang Lake fish and invertebrates. Five potential food sources (seston, benthic organic matter, aquatic macrophytes, attached algae, and terrestrial plants), 4 species of invertebrates, and 10 species of fish were collected from the lake area during dry and wet seasons between January 2009 and April 2010. The δ 13C values of invertebrates and most fish were within the range of δ 13C values of the potential food sources for both seasons. The δ 13C values of invertebrates and most fish were lower in the dry season than in the wet season, whereas the δ 15N values exhibited different patterns for different species. Mixing models indicated that the most important food sources for common lake fauna were seston in the dry season and aquatic macrophytes and terrestrial plants in the wet season. The fauna were more omnivorous in the wet season than in the dry season. The food web dynamics of Poyang Lake are strongly influenced by changes in the abundance and accessibility of different basal food sources that occur because of seasonal flood pulses. The trophic links within the aquatic communities of Poyang Lake are modified by water-level fluctuations.
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