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991.
There are no observations for methane emissions from landfill waste in Ireland. Methane emissions are imputed from waste data. There are intermittent data on waste sent to landfill. We compare two alternative ways to impute the missing waste “data” and evaluate the impact on methane emissions. We estimate Irish historical landfill quantities from 1960–2008 and Irish methane emissions from 1968–2006. A model is constructed in which waste generation is a function of income, price of waste disposal and, household economies of scale. A transformation ratio of waste to methane is also included in the methane emissions model. Our results contrast significantly with the Irish Environmental Protection Agency’s (EPA) figures due to the differences in the underlying assumptions. The EPA’s waste generation and methane emission figures are larger than our estimates from the early 1990s onwards. Projections of the distance to target show that the EPA overestimates the required policy effort.  相似文献   
992.
Environmental Chemistry Letters - Steroids are abundant in living organisms and are responsible for various biological functions. They are good candidates for inclusion complexes formation with...  相似文献   
993.
Assessing biodiversity vulnerability to future climate change is essential for developing robust adaptation strategies. A number of vulnerability assessment methodologies have been developed, from bioclimatic envelop models to more complex approaches that also consider biological traits and population status. However, the lack of comparative studies leaves the user to choose among the different methodologies without much guidance. This study applied three vulnerability assessment approaches to the Portuguese herpetofauna: (I) impact assessment approach based on bioclimatic models; (II) integrated vulnerability assessment approach, adding the evaluation of adaptive capacity to approach I; and (III) integrated vulnerability assessment and validation based on expert consultation. Results showed disagreement between the different approaches for 19 % of the species studied. Most differences were found between approach III and the two other approaches. All approaches showed advantages and limitations, the choice of a methodology being ultimately dependent on the study goals. Approach I has proven efficient to capture general vulnerability patterns. Approach II, although presenting results similar to approach I, allows for the identification of key factors affecting the species adaptive capacity and may be useful in tailoring adaptation measures. Approach III further allows us to identify knowledge gaps and to evaluate vulnerability when data availability or quality is reduced. Further, because this approach is based on an expert workshop, it has proven a perfect means to build on the vulnerability assessment results to identify indicator species and prioritize specific adaptation options.  相似文献   
994.
995.
Regional Environmental Change - Wetlands play important roles that benefit social-ecological systems. They are threatened by climate change and human activities, i.e., raising livestock and...  相似文献   
996.
Local medical systems are key elements of social-ecological systems as they provide culturally appropriate and locally accessible health care options, especially for populations with scarce access to biomedicine. The adaptive capacity of local medical systems generally rests on two pillars: species diversity and a robust local knowledge system, both threatened by local and global environmental change. We first present a conceptual framework to guide the assessment of knowledge diversity and redundancy in local medicinal knowledge systems through a gender lens. Then, we apply this conceptual framework to our research on the local medicinal plant knowledge of the Tsimane’ Amerindians. Our results suggest that Tsimane’ medicinal plant knowledge is gendered and that the frequency of reported ailments and the redundancy of knowledge used to treat them are positively associated. We discuss the implications of knowledge diversity and redundancy for local knowledge systems’ adaptive capacity, resilience, and health sovereignty.  相似文献   
997.
Unsustainable hunting outside protected areas is threatening tropical biodiversity worldwide and requires conservationists to engage increasingly in antipoaching activities. Following the example of ecocertified logging companies, we argue that other extractive industries managing large concessions should engage in antipoaching activities as part of their environmental management plans. Onshore hydrocarbon concessions should also adopt antipoaching protocols as a standard because they represent a biodiversity threat comparable to logging. We examined the spatiotemporal patterns of small‐ and large‐mammal poaching in an onshore oil concession in Gabon, Central Africa, with a Bayesian occupancy model based on signs of poaching collected from 2010 to 2015 on antipoaching patrols. Patrol locations were initially determined based on local intelligence and past patrol successes (adaptive management) and subsequently with a systematic sampling of the concession. We generated maps of poaching probability in the concession and determined the temporal trends of this threat over 5 years. The spatiotemporal patterns of large‐ and small‐mammal poaching differed throughout the concession, and likely these groups will need different management strategies. By elucidating the relationship between site‐specific sampling effort and detection probability, the Bayesian method allowed us to set goals for future antipoaching patrols. Our results indicate that a combination of systematic sampling and adaptive management data is necessary to infer spatiotemporal patterns with the statistical method we used. On the basis of our case study, we recommend hydrocarbon companies interested in implementing efficient antipoaching activities in their onshore concessions to lay the foundation of long‐needed industry standards by: adequately measuring antipoaching effort; mixing adaptive management and balanced sampling; setting goals for antipoaching effort; pairing patrols with large‐mammal monitoring; supporting antipoaching patrols across the landscape; restricting access to their concessions; performing random searches for bushmeat and mammal products at points of entry; controlling urban and agricultural expansion; supporting bushmeat alternatives; and supporting land‐use planning.  相似文献   
998.
As some species of game and free‐living animals promptly respond to ecosystem damage by a reaction that is easy to interpret, they are important ecological indicators in assessing the total contamination of the environment. Consumers of the highest order like predators, predatory and fish‐eating birds are among the most important bioindicators of environmental contamination by chlorinated hydrocarbons and PCB.

Data on chlorinated hydrocarbons and PCB levels were collected throughout 1988–1992 and obtained from 16 species of free‐living animals from 9 protected areas of Slovakia. Muscle tissue, liver, kidney and egg samples were examined for HCB, HCH isomers, DDT and its analogues, and PCB.

Levels of organic chlorinated contaminants reveal a decreasing tendency and thus cease to be a toxicologically important risk factor in game, with the exception of predatory birds, as significant values have been recorded in their eggs and reproductive organs.  相似文献   
999.
In altricial birds, parental feeding is essential, and its amount may depend on the quality of both parents. A relationship between parental quality and feeding rate is generally attributed to an active adjustment by parents in order to retain good quality mates or ensure high fitness through raising high-quality offspring. However, the behaviour and need of young may also change with parental quality, and this may affect parental behaviour. A further problem is that most studies have investigated post-hatching parental investment in relation to the secondary sexual signals of males, but not females. In a cross-fostering experiment, we examined the feeding rates of rearing parents in relation to the size and ornamentation of both original and rearing parents in collared flycatchers (Ficedula albicollis). Using this setup, we could examine whether the observed feeding patterns were the results of the decision of the parents based on their own and their partner’s traits or the constraints imposed by the behaviour or need of offspring. When correcting for clutch size and year, we found that feeding rate of both foster parents correlated with the wing patch size of the original female. This implies that original maternal quality had an offspring-mediated indirect effect on investment of foster parents, that is intrinsic nestling quality may constrain parental feeding decisions. This explanation should not be overlooked in future studies on preferential parental investment, and our results also point out that maternal ornaments deserve more attention in such studies.  相似文献   
1000.
ABSTRACT

The development of field-based biomarkers can allow for a more reliable assessment of the exposure of organisms to pollutants. Different sampling sites, along two streams running through an irrigable agricultural area, were selected to evaluate the effect of agrochemical load on the measured endpoints. The levels of lipid peroxidation were evaluated in several organs of Procambarus clarkii. The same method was applied to leaves of two woody species. Determining levels of MDA (malonaldehyde) by thiobarbituric acid reactive substances assay allows measuring the levels of lipid peroxidation. Differences in lipid peroxidation levels were observed in P. clarkii individuals collected at different sites; however, the patterns varied depending on the organ (when accounting for variations due to sex). The use of a MDA-gills/MDA-hepatopancreas index allowed for discrimination between reference and polluted sites. Significant differences in oxidative damage between sites were found in the leaves of Quercus rotundifolia but not in Salix sp. The lipid peroxidation of crayfish organs and holm oak leaves as a suitable biomarker of environmental pollution deserves further investigation.  相似文献   
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