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91.
Efford MG 《Ecology》2011,92(12):2202-2207
The recent development of capture-recapture methods for estimating animal population density has focused on passive detection using devices such as traps or automatic cameras. Some species lend themselves more to active searching: a polygonal plot may be searched repeatedly and the locations of detected individuals recorded, or a plot may be searched just once and multiple cues (feces or other sign) identified as belonging to particular individuals. This report presents new likelihood-based spatially explicit capture-recapture (SECR) methods for such data. The methods are shown to be at least as robust in simulations as an equivalent Bayesian analysis, and to have negligible bias and near-nominal confidence interval coverage with parameter values from a lizard data set. It is recommended on the basis of simulation that plots for SECR should be at least as large as the home range of the target species. The R package "secr" may be used to fit the models. The likelihood-based implementation extends the spatially explicit analyses available for search data to include binary data (animal detected or not detected on each occasion) or count data (multiple detections per occasion) from multiple irregular polygons, with or without dependence among polygons. It is also shown how the method may be adapted for detections along a linear transect.  相似文献   
92.
Despite an increased understanding of marine invasions, non-indigenous species (NIS) continue to be redistributed at both global and regional scales. Since prevention is an important element of NIS programs, monitoring vectors responsible for NIS introductions and spread, such as hull fouling, has become a priority and methods should be selected carefully to balance accuracy, time, and cost. Two common fouling assessment tools for the marine recreational boating vector were evaluated for accuracy using a traditional underwater SCUBA survey in coastal British Columbia: a dockside level of fouling assessment and a behavioral questionnaire model. Results showed that although rapid, dockside assessments did not provide an accurate assessment of fouling present below the surface, at least not in this region. In contrast, a questionnaire-based model using four easily obtained variables (boat type, age of antifouling paint, storage type, and occurrence of long distance trips) reliably identified boats carrying macrofouling species, a proxy for risk of NIS transport. Once validated, this fouling model tool could be applied in border inspection or quarantine situations where decisions must be made quickly. Further development and refinement of rapid assessment tools would improve our ability to prevent new introductions and manage spread of existing invasive species.  相似文献   
93.
There is a need for a global shift towards a low-carbon society and this requires action at the local level. The aim of the study into sustainable community development is to clarify the role of a community as a whole rather than the role of individuals within that community. Mixed methods of literature review and empirical study have been used to translate the knowledge and experience with urban sustainable development into empirical knowledge of a rural, market town setting. The exemplary case study is the Scottish market town Huntly. The main findings of the study show the need for three ingredients for a Community Sustainability Plan for a town such as Huntly. Community involvement is crucial in developing such plans in a rural setting. Further research in more remote settings, e.g. coastal and island communities, is needed to allow broader conclusions on rural sustainable development.  相似文献   
94.
An overview of bioreactor applications in treatment of gaseous, liquid and solid wastes is presented with emphasis on newer technologies. Waste treatment is considered in a broad context including concentration by bioaccumulation, degradation to substances with reduced environmental impact and upgrading to such useful products as feeds, foods and fuels. Biofilters and bioscrubbers for gaseous pollutants, high-rate municipal and industrial wastewater treatment in airlift bioreactors, reactor-based soil bioremediation, artificial wetland filters for liquid effluents, and protein enrichment of agricultural solid residues are some of the technologies reviewed. The various treatment strategies are illustrated with examples. The developments discussed point to an increasing role for bioreactor based processes in waste treatment and reuse.  相似文献   
95.
BACKGROUND: The ability for suicides of drivers to be disguised as traffic accidents raises the possibility that suicidal behaviors of this nature are far more prevalent than previously thought, potentially impacting health, road safety, and insurance companies. METHOD: Persons residing at the Gold Coast, Australia, identified as having a history of suicidal ideation and behaviors (n = 1,196), were sent a mail-out survey after their consent was obtained in initial telephone contact (CATI random digit-dialing). Among those responding, 412 had made suicide plans or arrangements and 228 suicide attempts. RESULTS: Of those who reported planning a suicide, 14.8% (19.1% of male planners and 11.8% of female planners) had conceived to have a motor vehicle "accident" (n = 61). Of all attempters, 8.3% (13.3% of male attempters) had previously attempted via motor vehicle collision (n = 19). All attempters reported having emotional or mental problems at the time of the event. Suicide planners were significantly more likely to be in full-time employment and have a partner and children compared with other planners. CONCLUSION: The study gives a rare insight into driver suicide plans and attempts, via a large-scale community survey, to provide the best opportunity of collecting unbiased data on the driver suicide behavior. Results suggest the use of this method, particularly in attempts made by males, may be underreported leading to inaccuracy of statistics. The motives behind choosing this method are somewhat different to those behind other methods, including financial benefits and eliminating stigma in the aftermath of a suicide.  相似文献   
96.
Journal of Material Cycles and Waste Management - The European Union emphasises the need to sever the link between economic growth, resource consumption and waste production and has set targets to...  相似文献   
97.
The unlimited economic growth that fuels capitalism's metabolism has profoundly transformed a large portion of Earth. The resulting environmental destruction has led to an unprecedented rate of biodiversity loss. Following large-scale losses of habitats and species, it was recognized that biodiversity is crucial to maintaining functional ecosystems. We sought to continue the debate on the contradictions between economic growth and biodiversity in the conservation science literature and thus invite scholars to engage in reversing the biodiversity crisis through acknowledging the impacts of economic growth. In the 1970s, a global agenda was set to develop different milestones related to sustainable development, including green–blue economic growth, which despite not specifically addressing biodiversity reinforced the idea that economic development based on profit is compatible with the planet's ecology. Only after biodiversity loss captured the attention of environmental sciences researchers in the early 2000s was a global biodiversity agenda implemented. The agenda highlights biodiversity conservation as a major international challenge and recognizes that the main drivers of biodiversity loss derive from economic activities. The post-2000 biodiversity agendas, including the 2030 Agenda for Sustainable Development and the post-2020 Convention on Biological Diversity Global Strategy Framework, do not consider the negative impacts of growth-oriented strategies on biodiversity. As a result, global biodiversity conservation priorities are governed by the economic value of biodiversity and its assumed contribution to people's welfare. A large body of empirical evidence shows that unlimited economic growth is the main driver of biodiversity loss in the Anthropocene; thus, we strongly argue for sustainable degrowth and a fundamental shift in societal values. An equitable downscaling of the physical economy can improve ecological conditions, thus reducing biodiversity loss and consequently enhancing human well-being.  相似文献   
98.
In this note, we applied the temporal moment solutions of [Das and Kluitenberg, 1996. Soil Sci. Am. J. 60, 1724] for one-dimensional advective-dispersive solute transport with linear equilibrium sorption and first-order degradation for time pulse sources to analyse soil column experimental data. Unlike most other moment solutions, these solutions consider the interplay of degradation and sorption. This permits estimation of a first-order degradation rate constant using the zeroth moment of column breakthrough data, as well as estimation of the retardation factor or sorption distribution coefficient of a degrading solute using the first moment. The method of temporal moment (MOM) formulae was applied to analyse breakthrough data from a laboratory column study of atrazine, hexazinone and rhodamine WT transport in volcanic pumice sand, as well as experimental data from the literature. Transport and degradation parameters obtained using the MOM were compared to parameters obtained by fitting breakthrough data from an advective-dispersive transport model with equilibrium sorption and first-order degradation, using the nonlinear least-square curve-fitting program CXTFIT. The results derived from using the literature data were also compared with estimates reported in the literature using different equilibrium models. The good agreement suggests that the MOM could provide an additional useful means of parameter estimation for transport involving equilibrium sorption and first-order degradation. We found that the MOM fitted breakthrough curves with tailing better than curve fitting. However, the MOM analysis requires complete breakthrough curves and relatively frequent data collection to ensure the accuracy of the moments obtained from the breakthrough data.  相似文献   
99.
Urban community gardens provide affordable, locally grown, healthy foods and many other benefits. However, urban garden soils can contain lead (Pb) that may pose risks to human health. To help evaluate these risks, we measured Pb concentrations in soil, vegetables, and chicken eggs from New York City community gardens, and we asked gardeners about vegetable consumption and time spent in the garden. We then estimated Pb intakes deterministically and probabilistically for adult gardeners, children who spend time in the garden, and adult (non-gardener) household members. Most central tendency Pb intakes were below provisional total tolerable intake (PTTI) levels. High contact intakes generally exceeded PTTIs. Probabilistic estimates showed approximately 40 % of children and 10 % of gardeners exceeding PTTIs. Children’s exposure came primarily from dust ingestion and exposure to higher Pb soil between beds. Gardeners’ Pb intakes were comparable to children’s (in µg/day) but were dominated by vegetable consumption. Adult household members ate less garden-grown produce than gardeners and had the lowest Pb intakes. Our results suggest that healthy gardening practices to reduce Pb exposure in urban community gardens should focus on encouraging cultivation of lower Pb vegetables (i.e., fruits) for adult gardeners and on covering higher Pb non-bed soils accessible to young children. However, the common practice of replacement of root-zone bed soil with clean soil (e.g., in raised beds) has many benefits and should also continue to be encouraged.  相似文献   
100.
Geochemical analysis and visual inspection of cores collected from capped dredged material mounds revealed that in many cores, cap material was clearly distinguishable, both visually and chemically, from mound material. Contaminated dredged sediments were disposed in Long Island Sound eleven and seven years prior to sampling, and capped with uncontaminated dredged sediments. Core data provided no conclusive evidence of physical disturbance of, or chemical migration from, the contaminated mound sediments. Obvious chemical gradients of contaminant concentrations, which we propose are indicators of chemical migration, were not detected in the cores. Heterogeneity of the cap and mound sediments in some cores made the interface less distinct. We postulate that the preservation of spatial variability of sediment texture and associated contaminants observed within dredged material mounds is a result of the dredging process. Preservation of the textural and contaminant history of dredged sediments within finegrained cohesive cap materials provides evidence of the absence of physical or chemical disturbance.  相似文献   
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