排序方式: 共有43条查询结果,搜索用时 31 毫秒
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Giallonardo T Landi M Frignani F Geri F Lastrucci L Angiolini C 《Environmental monitoring and assessment》2011,182(1-4):141-154
The aims of the present study were to: (1) investigate whether CORINE land cover classes reflect significant differences in floristic composition, using a very detailed CORINE land cover map (scale 1:5000); (2) decompose the relationships between floristic assemblages and three groups of explanatory variables (CORINE land cover classes, environmental characteristics and spatial structure) into unique and interactive components. Stratified sampling was used to select a set of 100-m(2) plots in each land cover class identified in the semi-natural wetland surrounding a lake in central Italy. The following six classes were considered: stable meadows, deciduous oak dominated woods, hygrophilous broadleaf dominated woods, heaths and shrublands, inland swamps, canals or watercourses. The relationship between land cover classes and floristic composition was tested using several statistical techniques in order to determine whether the results remained consistent with different procedures. The variation partitioning approach was applied to identify the relative importance of three groups of explanatory variables in relation to floristic variation. The most important predictor was land cover, which explained 20.7% of the variation in plant distribution, although the hypothesis that each land cover class could be associated with a particular floristic pattern was not verified. Multi Response Permutation Analysis did not indicate a strong floristic separability between land cover classes and only 9.5% of species showed a significant indicator value for a specific land cover class. We suggest that land cover classes linked with hygrophilous and herbaceous communities in a wetland may have floristic patterns that vary with fine scale and are not compatible with a land cover map. 相似文献
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Carola Borries Tommaso Savini Andreas Koenig 《Behavioral ecology and sociobiology》2011,65(4):685-693
The evolution of social monogamy in larger mammals is difficult to explain because males usually do not invest much in direct
offspring care and might achieve greater fitness by deserting a pregnant female to reproduce with additional females elsewhere.
It has been hypothesized that socially monogamous males remain with the female year-round to protect their offspring from
infanticide by new immigrant males. We investigated this idea by analyzing all cases of infant loss in a wild population of
white-handed gibbons (Hylobates lar; Primates), in which most groups were socially monogamous and some polyandrous (137.5 group years). We examined the influence
of (a) male intruder pressure on male immigration rates and (b) the presence of a new male in the group on infant loss. We
found no relation between intruder pressure and male immigration rates. Infant loss was lowest (4.5%) for stable monogamy
(probable father stayed from conception through infancy) and intermediate (25.0%; p = 0.166) for stable polyandry. If a new male immigrated after conception, however, the infant was lost in all cases (p < 0.01) independent of the presumed father’s presence. Overall, 83.3% of infant losses were associated with the presence
of a presumably unrelated male. Although the sample size is small, our results provide the first true support for the idea
that the risk of infanticide is an important factor in the evolution of social monogamy in larger mammals. 相似文献
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Valter M. Azevedo-Santos Marcelo F. G. Brito Pedro S. Manoel Júlia F. Perroca Jorge Luiz Rodrigues-Filho Lucas R. P. Paschoal Geslaine R. L. Gonalves Milena R. Wolf Martín C. M. Blettler Marcelo C. Andrade Andr B. Nobile Felipe P. Lima Ana M. C. Ruocco Carolina V. Silva Gilmar Perbiche-Neves Jorge L. Portinho Tommaso Giarrizzo Marlene S. Arcifa Fernando M. Pelicice 《Ambio》2021,50(7):1313
Plastics are dominant pollutants in freshwater ecosystems worldwide. Scientific studies that investigated the interaction between plastics and freshwater biodiversity are incipient, especially if compared to the marine realm. In this review, we provide a brief overview of plastic pollution in freshwater ecosystems around the world. We found evidence of plastic ingestion by 206 freshwater species, from invertebrates to mammals, in natural or semi-natural ecosystems. In addition, we reported other consequences of synthetic polymers in freshwater ecosystems—including, for instance, the entanglement of animals of different groups (e.g., birds). The problem of plastic pollution is complex and will need coordinated actions, such as recycling programs, correct disposal, stringent legislation, regular inspection, replacement of synthetic polymers with other materials, and ecological restoration. Current information indicates that the situation in freshwater ecosystems may be as detrimental as the pollution found in the ocean, although highly underappreciated.Supplementary InformationThe online version of this article (10.1007/s13280-020-01496-5) contains supplementary material, which is available to authorized users. 相似文献
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Renato Baciocchi Ennio Carnevale Giulia Costa Renato Gavasci Lidia Lombardi Tommaso Olivieri Laura Zanchi Daniela Zingaretti 《Waste management (New York, N.Y.)》2013,33(12):2694-2705
This work analyzes the performance of an innovative biogas upgrading method, Alkali absorption with Regeneration (AwR) that employs industrial residues and allows to permanently store the separated CO2. This process consists in a first stage in which CO2 is removed from the biogas by means of chemical absorption with KOH or NaOH solutions followed by a second stage in which the spent absorption solution is contacted with waste incineration Air Pollution Control (APC) residues. The latter reaction leads to the regeneration of the alkali reagent in the solution and to the precipitation of calcium carbonate and hence allows to reuse the regenerated solution in the absorption process and to permanently store the separated CO2 in solid form. In addition, the final solid product is characterized by an improved environmental behavior compared to the untreated residues. In this paper the results obtained by AwR tests carried out in purposely designed demonstrative units installed in a landfill site are presented and discussed with the aim of verifying the feasibility of this process at pilot-scale and of identifying the conditions that allow to achieve all of the goals targeted by the proposed treatment. Specifically, the CO2 removal efficiency achieved in the absorption stage, the yield of alkali regeneration and CO2 uptake resulting for the regeneration stage, as well as the leaching behavior of the solid product are analyzed as a function of the type and concentration of the alkali reagent employed for the absorption reaction. 相似文献
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