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211.
212.
Williams Paula Alessa Lilian Abatzoglou John T. Kliskey Andrew Witmer Frank Lee Olivia Trammell Jamie Beaujean Grace Venema Rieken 《Regional Environmental Change》2018,18(2):547-559
Regional Environmental Change - Many papers have addressed the differing approaches to observation by scientists collecting instrumented data and by community or local knowledge-based observations.... 相似文献
213.
William R. L. Anderegg Leander D. L. Anderegg Clare Sherman Daniel S. Karp 《Conservation biology》2012,26(6):1082-1090
Forest die‐off around the world is expected to increase in coming decades as temperature increases due to climate change. Forest die‐off will likely affect understory plant communities, which have substantial influence on regional biological diversity, ecosystem function, and land–atmosphere interactions, but how die‐off alters these plant communities is largely unknown. We examined changes in understory plant communities following a widespread, drought‐induced die‐off of trembling aspen (Populus tremuloides) in the western United States. We assessed shrub and herbaceous cover and volume in quadrats in 55 plots located across a wide range of levels of aspen mortality. We measured species richness and composition of herbaceous plant communities by recording species presence and absence in 12 sets of paired (1 healthy, 1 dying) aspen plots. Although understory composition in healthy and dying stands was heterogeneous across the landscape, shrub abundance, cover, and volume were higher and abundance of herbaceous species, cover, and volume were lower in dying aspen stands. Shrub cover and volume increased from 2009 to 2011 in dying stands, which suggests that shrub growth and expansion is ongoing. Species richness of herbs declined by 23% in dying stands. Composition of herbs differed significantly between dying and healthy stands. Richness of non‐native species did not differ between stand types. The understory community in dying aspen stands was not similar to other shrub‐dominated plant communities in the region and may constitute a novel community. Our results suggest that changes in understory plant communities as forests die off could be a significant indirect effect of climate change on biological diversity and forest communities. Efectos de la Mortalidad Extensiva de Álamos Inducida por Sequía sobre Plantas del Sotobosque 相似文献
214.
Gareth D. Lennox Joseph Fargione Sacha Spector Gwyn Williams Paul R. Armsworth 《Conservation biology》2017,31(3):666-674
Land‐acquisition strategies employed by conservation organizations vary in their flexibility. Conservation‐planning theory largely fails to reflect this by presenting models that are either extremely inflexible—parcel acquisitions are irreversible and budgets are fixed—or extremely flexible—previously acquired parcels can readily be sold. This latter approach, the selling of protected areas, is infeasible or problematic in many situations. We considered the value to conservation organizations of increasing the flexibility of their land‐acquisition strategies through their approach to financing deals. Specifically, we modeled 2 acquisition‐financing methods commonly used by conservation organizations: borrowing and budget carry‐over. Using simulated data, we compared results from these models with those from an inflexible fixed‐budget model and an extremely flexible selling model in which previous acquisitions could be sold to fund new acquisitions. We then examined 3 case studies of how conservation organizations use borrowing and budget carry‐over in practice. Model comparisons showed that borrowing and budget carry‐over always returned considerably higher rewards than the fixed‐budget model. How they performed relative to the selling model depended on the relative conservation value of past acquisitions. Both the models and case studies showed that incorporating flexibility through borrowing or budget carry‐over gives conservation organizations the ability to purchase parcels of higher conservation value than when budgets are fixed without the problems associated with the selling of protected areas. 相似文献
215.
A newly constructed coastal revetment at Colhuw Beach in the Glamorgan Heritage Coast, Wales, UK, was analysed using a recently
developed environmental risk assessment package (ERA). Conflict with Heritage Coast conservation objectives is apparent and
the act of building such a structure is questioned for a location where maintenance ofnatural beauty is an axiom of the coastal management philosophy. The likelyhood of revetment related environmental consequences of
significant magnitude was analysed using estimated probability values derived from Bayesian theory. The damaging impact of
the structure on the natural environment is out of all proportion to the level of storm protection afforded to the site. Analyses,
such as carried out via ERA, would have shown planners, engineers and environmentalists, the inadequacies of such an investment
and management strategy. The ERA approach can help to introduce greater clarity and consistency into decision making processes. 相似文献
216.
A newly constructed coastal revetment at Colhuw Beach in the Glamorgan Heritage Coast, Wales, UK, was analysed using a recently
developed environmental risk assessment package (ERA). Conflict with Heritage Coast conservation objectives is apparent and
the act of building such a structure is questioned for a location where maintenance ofnatural beauty is an axiom of the coastal management philosophy. The likelyhood of revetment related environmental consequences of
significant magnitude was analysed using estimated probability values derived from Bavesian theory. The damaging impact of
the structure on the natural environment is out of all proportion to the level of storm protection afforded to the site. Analyses,
such as carried out via ERA, would have shown planners, engineers and environmentalists, the inadequacies of such an investment
and management strategy. The ERA approach can help to introduce greater clarity and consistency into decision making processes. 相似文献
217.
Zena Lam Elizabeth Wall Gavin Ryan Richard Barber Mark D. Kilby Denise K. Williams 《黑龙江环境通报》2023,43(9):1247-1250
We report two male fetuses born to a healthy unrelated couple, with agenesis of the corpus callosum identified on detailed 20-week ultrasound scans and confirmed by in-utero MRI. Whole-genome sequencing identified a likely pathogenic missense variant in the CLCN4 gene, establishing this as the causative gene in the family. Pathogenic variants in the CLCN4 gene cause a neurodevelopmental disorder (also called Raynaud-Claes syndrome) inherited in an X-linked pattern. The disorder is characterised by developmental delay, intellectual disability, autism spectrum disorder, epilepsy, mental health conditions, and significant feeding difficulties, predominantly, but not exclusively, affecting males. This is the first report of a prenatal phenotype associated with variants in the CLCN4 gene. The diagnosis of the CLCN4-related neurodevelopmental disorder in this family allowed accurate genetic counseling and discussion of reproductive choices. This leaves uncertainty about the possibility of a postnatal neurodevelopmental phenotype in heterozygous females, which we discuss. 相似文献
218.
M. Williams T. Yamada 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1266-1274
Most atmospheric transport and diffusion models within emergency response systems have very limited physics and are forced to rely on the assumption that wind and turbulence conditions at the time of the release will be representative over the period for which dispersion must be predicted. For releases where the principal concern is about the first few kilometers of travel, such an assumption is appropriate. However, for large accidental releases during stable conditions, the plume may travel for several hours before it is diluted to safe levels and the assumption of persistence may be inappropriate, particularly for transport in complex terrain. Under these circumstances, a model that can forecast changes in wind and turbulence conditions is required. We have installed such a model on microcomputers and tested it in complex terrain near Salt Lake City. One-hour tracer releases produced surface concentrations that remain high for much longer times than that expected based on one hour’ travel time with the mean wind at the source height. Furthermore, relatively large concentrations were found at distances of over 40 km from the source. The model was generally able to reproduce the principal features described by the measurements, although some effects of subgrid scale terrain were missed. 相似文献
219.
Giovanni De Feo Sabino De Gisi Ian D. Williams 《Waste management (New York, N.Y.)》2013,33(4):974-987
If residents’ perceptions, concerns and attitudes towards waste management facilities are either not well understood or underestimated, people can produce strong opposition that may include protest demonstrations and violent conflicts such as those experienced in the Campania Region of Italy. The aim of this study was to verify the effects of the closure of solid waste treatment and disposal facilities (two landfills and one RDF production plant) on public perception of odour and environmental pollution. The study took place in four villages in Southern Italy. Identical questionnaires were administered to residents during 2003 and after the closure of the facilities occurred in 2008. The residents’ perception of odour nuisance considerably diminished between 2003 and 2009 for the nearest villages, with odour perception showing an association with distance from the facilities. Post closure, residents had difficulty in identifying the type of smell due to the decrease in odour level. During both surveys, older residents reported most concern about the potentially adverse health impacts of long-term exposure to odours from MSW facilities. However, although awareness of MSW facilities and concern about potentially adverse health impacts varied according to the characteristics of residents in 2003, substantial media coverage produced an equalisation effect and increased knowledge about the type of facilities and how they operated. It is possible that residents of the village nearest to the facilities reported lower awareness of and concern about odour and environmental pollution because the municipality received economic compensation for their presence. 相似文献
220.
Paul T. Williams 《Waste management (New York, N.Y.)》2013,33(8):1714-1728
Approximately 1.5 billion tyres are produced each year which will eventually enter the waste stream representing a major potential waste and environmental problem. However, there is growing interest in pyrolysis as a technology to treat tyres to produce valuable oil, char and gas products. The most common reactors used are fixed-bed (batch), screw kiln, rotary kiln, vacuum and fluidised-bed. The key influence on the product yield, and gas and oil composition, is the type of reactor used which in turn determines the temperature and heating rate. Tyre pyrolysis oil is chemically very complex containing aliphatic, aromatic, hetero-atom and polar fractions. The fuel characteristics of the tyre oil shows that it is similar to a gas oil or light fuel oil and has been successfully combusted in test furnaces and engines. The main gases produced from the pyrolysis of waste tyres are H2, C1–C4 hydrocarbons, CO2, CO and H2S. Upgrading tyre pyrolysis products to high value products has concentrated on char upgrading to higher quality carbon black and to activated carbon. The use of catalysts to upgrade the oil to a aromatic-rich chemical feedstock or the production of hydrogen from waste tyres has also been reported. Examples of commercial and semi-commercial scale tyre pyrolysis systems show that small scale batch reactors and continuous rotary kiln reactors have been developed to commercial scale. 相似文献