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11.
Fish may significantly affect habitat use by birds, either as their prey or as competitors. Fish communities are often distinctly size-structured, but the consequences for waterbird assemblages remain poorly understood. We examined the effects of size structure of common carp (Cyprinus carpio) cohorts together with other biotic and abiotic pond characteristics on the distribution of breeding waterbirds in a seminatural system of monocultured ponds, where three fish age classes were separately stocked. Fish age corresponded to a distinct fish size gradient. Fish age and total biomass, macroinvertebrate and amphibian abundance, and emergent vegetation best explained the differences in bird density between ponds. Abundance of animal prey other than fish (aquatic macroinvertebrates and larval amphibians) decreased with increasing carp age in the ponds. Densities of ducks and smaller grebes were strongly negatively associated with fish age/size gradient. The largest of the grebes, the piscivorous great crested grebe (Podiceps cristatus), was the only species that preferred ponds with medium-sized fish and was positively associated with total fish biomass. Habitat selection by bitterns and most rallids was instead strongly influenced by the relative amount of emergent vegetation cover in the ponds. Our results show that fish size structure may be an important cue for breeding habitat choice and a factor affording an opportunity for niche diversification in avian communities.  相似文献   
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Environmental Science and Pollution Research - Refuse-derived fuel (RDF) can be produced from combustible materials contained in municipal waste. This article investigates energy and material flow...  相似文献   
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In this paper, we present applied methanol recycling technology utilising Chromatographic applications, which has been designed for an academic-size institution. The procedure is combined out of proper recovery technique and the biodegradation method intended for postprocessing residues. Additionally, analytical methods controlling the quality of the process are described in detail in order to enable full transfer of the proposed methodology to the analogous institution. The recovered solvent is of relatively high purity (> 99.92%), containing traces of water and volatile compounds. The spectral purity is sufficient to employ recycled methanol in HPLC applications where low wayelength detection is necessary. Biodegradation of distillation first-cuts and still bottoms is implemented using isolated strains ofMethylobacterium organophilum. During the biodegradation process, a series of carotenoids are biosynthesized, which are of a high commercial value. The proposed application, therefore, offers not only a sustainable, waste-free solution in handling methanol waste, but can also serve as a potential source of value.  相似文献   
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Whilst mitigation has dominated policy and research agendas in recent years there is an increasing recognition that communities also need to be preparing for change that is unavoidable, partially a consequence of anthropogenic greenhouse gases already emitted to the atmosphere. The perceived need for adaptation has also received additional impetus through the high public profile now given to the impacts of current day weather variability, particularly the significant economic and social costs associated with recent extreme events. However, being a relatively new focus for both research and policy communities; practical evidence of the extent, feasibility, efficiency, and cost effectiveness of potential adaptation options remains largely lacking. In response, this paper seeks to make a contribution to this embryonic but evolving knowledge base by considering the theoretical underpinnings of adaptation and ultimately how this translates into practice ‘in the real world’. The analytical commentary, based on a bottom-up approach involving iterative engagement with key stakeholders and experts, reflects on the identification of measures that are either innovative or examples of good practice in reducing or transferring climate risks, as well as considering those ‘enabling’ institutional structures and processes that act to support implementation on the ground. The paper concludes by synthesising the key findings to date in order to highlight some of the opportunities for, and barriers to, adaptation activity.  相似文献   
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Mitigation and Adaptation Strategies for Global Change - This paper addresses the problem of learning in greenhouse gas (GHG) emission inventories understood as reductions in uncertainty, i.e.,...  相似文献   
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Corn distillers’ dry grain, corncob powder, hardwood powder, and sugar beet pulp were separately anionized by oxidation with sodium hypochlorite in aqueous solution. Solid reaction products instantly precipitated upon admixing each of the above-oxidized materials with soy protein isolate. Infrared spectra and differential scanning calorimetry supported the hypothesis that soy protein isolate complexed with all of the above-oxidized polysaccharides. Reaction products with either oxidized corn distillers’ dry grain or oxidized sugar beet pulp provided hard, brittle pellets with tensile strengths as high as 9.5 MPa, suggesting that these materials could be viable as biodegradable plastics.  相似文献   
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The concentrations of heavy metals (Cd, Cu, Ni, Pb, Zn and Mn) and macroelements (K, Na, Ca and Mg) were determined in green alga Enteromorpha sp. from the coastal zone of the southern Baltic including Gulf of Gdańsk and Vistula Lagoon in 2000-2003. In order to estimate the degree of accumulation of each element by the green alga, concentration and discrimination factors (CFs) with respect to seawater were calculated. The results of factor analysis (FA) and ANOVA clearly indicate geographical differences between concentrations of chemical elements. Enteromorpha sp. from Vistula Lagoon and the southern Baltic exhibited higher levels of Mn and Ni, and Na and K, respectively. Anthropogenic impact of Cu, Pb and Zn, possibly originated from municipal sewage, was identified in alga samples collected in the Gulf of Gdańsk, especially in the vicinity of Gdynia. From comparison our data with those published earlier results that Pb content in Enteromorpha sp. from the Gulf of Gdańsk decreased within 1978-2003 reflecting reducing use of leaded petrol in Baltic countries in this period. The alga Enteromorpha sp. can be used for biomonitoring surveys of metal contaminants in coastal areas of the Baltic Sea.  相似文献   
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