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Capelin is a planktivorous key fish species in many subarctic ecosystems representing the link between lower trophic levels and apex predators. Little is known, however, of capelin in Greenland waters, but it has been suggested that size and growth increases due to difference in food availability and temperature conditions along a 1,500 km south–north gradient on the west coast. It is presently unknown how the qualitative state of capelin energy content is affected along this gradient. Based on 2007 and 2008 samples, we show that energy content increases with capelin length in both spawning and non-spawning fish and that it varies with latitude in spawning fish along West Greenland (60–71°N). Combining our results on energy content with information on capelin growth along the same latitudinal climate gradient demonstrates that less and lower-quality food is available to capelin predators in the south than in the north.  相似文献   
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Environmental Science and Pollution Research - Plastic has become the most widespread human-made material and small fragments (< 5mm, so called microplastics, MPs) accumulate in all the...  相似文献   
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Environmental Science and Pollution Research - Aquatic organisms are continuously exposed to emerging contaminants coming from urban effluents of wastewater treatment plants. The contamination of...  相似文献   
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Abstract: Livestock grazing (without modern fertilizers), mowing, and other traditional methods of animal husbandry are used in Europe for managing human-made habitats such as seminatural grasslands. From a review of essential literature, I hypothesize that traditional animal husbandry partially compensates for the loss of natural processes that have been suppressed by humans. There is indirect evidence that livestock grazing and mowing have made possible the continued existence of many species threatened by the human overkill of megaherbivores and other large herbivores. Many species that were dependent on natural fires and floods may have benefited from grazing and mowing, which also may be effective tools for mitigating the negative effects of eutrophication. As partial surrogates, traditional grazing and mowing have obscured the importance of natural disturbances to European biodiversity. Thus, the end of traditional animal husbandry, together with the suppression of natural disturbances, may cause even more adverse effects to biodiversity than is generally recognized.  相似文献   
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Concerns over water scarcity, climate change, and environmental health risks have prompted some Asian cities to invest in river rehabilitation, but deciding on the end goals of rehabilitation is a complex undertaking. We propose a multidisciplinary framework linking riparian landscape change to human well‐being, providing information relevant to decision makers, in a format that facilitates stakeholder involvement. We illustrate this through a case study of the densely settled, environmentally degraded, and flood prone Ciliwung River flowing through metropolitan Jakarta, Indonesia. Our methodology attempts to respond to this complexity through an iterative approach, strongly based on conceptualization and mathematical modeling. Nested hydrologic, hydrodynamic, and water quality models provide outputs at catchment‐, corridor‐, and localized site‐scales. Advanced 3‐D landscape modeling is used for procedural design and precise visualization of proposed changes and their impacts, as predicted by the mathematical models. Finally, participatory planning and design methods allow us to obtain critical stakeholder feedback in shaping a socially acceptable approach. Our framework aims at demonstrating that a change in paradigm in river rehabilitation is possible, and providing future scenarios that balance concerns over flooding, water quality, and ecology, with the realities of a rapidly growing megacity.  相似文献   
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Models were developed for predicting the decomposition of dead wood for the main tree species in Finland, based on data collected from long-term thinning experiments in southern and central Finland. The decomposition rates were strongly related to the number of years after tree death. In contrast to previous studies, which have used the first-order exponential model, we found that the decomposition rate was not constant. Therefore, the Gompertz and Chapman-Richard's functions were fitted to the data. The slow initial decomposition period was mainly due to the fact that most dead trees remained standing as snags after their death. The initial period was followed by a period of rapid decomposition and, finally, by a period of moderately slow decomposition. Birch stems decomposed more rapidly than Scots pine and Norway spruce stems. Decomposition rates of Norway spruce stems were somewhat lower than those of Scots pine. Because the carbon concentration of decaying boles was relatively stable (about 50%) the rate of carbon loss follows that of mass loss. Models were also developed for the probability that a dead tree remains standing as a snag. During the first years after death, the probability was high. Thereafter, it decreased rapidly, the decrease being faster for birch stems than for Scots pine and Norway spruce stems. Almost all stems had fallen down within 40 years after their death. In Scots pine and Norway spruce, most snags remained hard and belonged to decay class 1. In birch, a higher proportion of snags belonged to the more advanced decay classes. The models provide a framework for predicting dead wood dynamics in managed as well as dense unthinned stands. The models can be incorporated into forest management planning systems, thereby facilitating estimates of carbon dynamics.  相似文献   
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