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921.
Conservation scientists have noted that conservation managers rarely use scientific information when making decisions. One of the reasons why managers rarely use scientific information may be that conservation scientists rarely provide their knowledge in a way that can directly be used by conservation practitioners. Here we show how quantitative recommendations for conservation can be derived. Previous research on terrestrial habitat selection behavior of toads (Bufo bufo and Bufo viridis) showed that wood deposits are a key resource in the terrestrial habitat. We used habitat-dependence analysis to estimate the amount of this key resource, wood deposits, that individual toads require. Based on these estimates we then quantify the requirements for wood deposits for a population. Additionally, we quantified the area that a population requires. Although wood deposits vary strongly in size, we found little evidence for size preferences: only one species preferred smallest sizes of wood deposits. We report all the estimates in a way that can be directly used by conservation managers. Habitat-dependence analysis is a simple and useful tool to quantify habitat requirements. Provisioning of wood deposits may improve the quality of terrestrial habitat for amphibians. Thereby, managers may increase the carrying capacity of terrestrial habitats and support elevated population densities.  相似文献   
922.
To date, the vast majority of studies in urban areas have been carried out on birds, yet it is not known whether the responses of birds to urbanization are congruent with those of other taxa. In this paper, we compared the responses of breeding birds and carabid beetles to urbanization, specifically asking whether the emerging generalizations of the effects of extreme levels of urbanization on birds (declines in total species richness and the richness of specialist species, increases in total abundance and the abundances of native generalist and introduced species, and community simplification, including increasing similarity) could also be applied to ground beetles. We also directly tested for congruence between birds and ground beetles using correlations between variables describing bird and beetle community structure and correlations between bird and beetle distance matrices describing community dissimilarity between pairs of sampling locations. Breeding bird and carabid beetle community data were collected in Ottawa, Ontario, and Gatineau, Quebec, Canada, in two groups of sites: developed sites representing the predictor variable within-site housing density, and forested sites adjacent to development representing the predictor variable neighboring housing density (each site was 0.25 km2). Breeding birds and carabid beetles do not respond similarly to increasing within-site housing density but do exhibit some similar responses to increasing neighboring housing density. Birds displayed strong declines in diversity, compositional changes, and community simplification in response to increasing within-site housing density. Forest and introduced species of birds and beetles responded similarly to increasing housing density within a site, but responses of overall diversity and open-habitat species richness and patterns of community simplification differed between birds and beetles. Increasing neighboring housing density resulted in increases in the abundances of introduced birds and introduced beetles and similar patterns of community simplification in both taxa. To better understand and mitigate the effects of urbanization on biodiversity, we suggest that, in addition to the responses of birds, future research should focus on the responses of other taxa in the urban matrix.  相似文献   
923.
Spatial and temporal trends of tributyltin (TBT) pollution on the northern continental shelf of Portugal (5-34 m depth) were assessed using Nassarius reticulatus as a bioindicator. Imposex levels were determined in 2006 and 2010, and integrated with age readings from statoliths for a better chronological analysis of the data. Females affected with imposex were detected in 84% of the sites surveyed in 2006, with levels higher than the Ecological Quality Objective (EcoQO) set by the OSPAR Commission for N. reticulatus (VDSI < 0.3) in approximately half of those sites. In 2010, imposex was only detected in 20% of the surveyed sites and, when detected, the VDSI were lower than the EcoQO, except for one location. The comparison between the current results and the levels previously reported for 2004 and 2005 in the same offshore area evidences a clear decline of imposex in 2010 that confirms the efficacy of Regulation (EC) No. 782/2003 and the IMO AFS-Convention (entered into force in 2003 and 2008, respectively). Moreover, the age of the whelks used in the monitoring is estimated in 3-5 years, indicating that actual TBT water contamination in 2010 may in fact be lower than that extrapolated from the imposex levels. We conclude that the legislation was indeed very effective in reducing TBT pollution in the NW Portuguese continental shelf, not only in terms of the magnitude but also in terms of fast field repercussion.  相似文献   
924.

The identification of species-rich areas and their prognosticated turnover under climate change are crucial for the conservation of endemic taxa. This study aims to identify areas of reptile endemicity richness in a global biodiversity hot spot (Morocco) under current and future climatic conditions and to investigate the role of protected areas in biodiversity conservation under climate change. Species distribution models (SDM) were performed over the distribution of 21 endemic reptiles, combined to estimate current species richness at 1?×?1 km resolution and projected to years 2050 and 2080 according to distinct story lines and ensemble global circulation models, assuming unlimited and null dispersion ability. Generalized additive models were performed between species richness and geographic characteristics of 43 protected areas. SDM found precipitation as the most important factor related to current species distributions. Important reductions in future suitable areas were predicted for 50 % of species, and four species were identified as highly vulnerable to extinction. Drastic reductions in species-rich areas were predicted for the future, with considerable variability between years and dispersal scenarios. High turnover rates of species composition were predicted for eastern Morocco, whereas low values were forecasted for the Northern Atlantic coast and mountains. Species richness for current and future conditions was significantly related to the altitude and latitude of protected areas. Protected areas located in mountains and/or in the Northern Atlantic coast were identified as refugia, where population monitoring and conservation management is needed.

  相似文献   
925.
Environmental Science and Pollution Research - Multilayer graphene oxide (mGO) was synthesized and functionalized via co-precipitation method to produce magnetic Fe3O4-functionalized multilayer...  相似文献   
926.
Environmental Science and Pollution Research - Neonicotinoids are a class of pesticides widely used in different phases of agricultural crops. Similar to other classes of pesticides, they can...  相似文献   
927.
Environmental Science and Pollution Research - The present work aimed to analyze the mineral nutrition of Physalis angulata L. under stress by aluminum in the nutrient solution. The treatments...  相似文献   
928.
Environmental Science and Pollution Research - Mercury and selenium concentrations and Se:Hg molar ratio in edible muscle and hepatopancreas of the crab Callinectes arcuatus from coastal lagoons of...  相似文献   
929.
Environmental Science and Pollution Research - Briquetting is a technology with the potential to convert agricultural wastes into solid biofuels with improved handling, transport, storage, and...  相似文献   
930.

The urban groundwater of the Quaternary aquifer of the Lake Chad basin in N’Djamena has been subject to many hydrochemical studies. However, the results are often not presented in a way that enables water quality managers to make an appropriate decisions, which restrict development and poverty reduction efforts. The objective of the present study was to contribute the improved management of the local groundwater resources. A total of 85 groundwater samples were interpreted using hydrochemical techniques associated with integrated numerical indices and multivariate statistical analysis. The hydrochemical results coupled with the relative residence time of water have shown that the chemical composition of these waters is linked to geogenic and anthropogenic factors and to their proximity to the Chari-Logone rivers. These investigations showed that the groundwater quality in N’Djamena is characterized by a high spatial variability. This study also assessed the suitability of groundwater for user needs and identified areas which are more/less favorable for a specific use. The evaluation of water quality and its suitability for human consumption is also a problem of optimizing data acquisition strategy, and this study used the correlation between water quality index (WQI) and electrical conductivity (EC) to orientate future data acquisition strategies. This parametrization can assist the decision makers and water management professionals in evaluating groundwater availability and setting up a robust water quality management plan in areas with similar hydrogeological and climatic conditions.

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