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141.
The continuing decline and loss of biodiversity has caused an increase in the use of interventionist conservation tools, such as translocation. However, many translocation attempts fail to establish viable populations, with poor release site selection often flagged as an inhibitor of success. We used species distribution models (SDMs) to predict the climate suitability of 102 release sites for amphibians, reptiles, and terrestrial insects and compared suitability predictions between successful and failed attempts. We then quantified the importance of climate suitability relative to 5 other variables frequently considered in the literature as important determinants of translocation success: number of release years, number of individuals released, life stage released, origin of the source population, and position of the release site relative to the species’ range. Probability of translocation success increased as predicted climate suitability increased and this effect was the strongest among the variables we considered, accounting for 48.3% of the variation in translocation outcome. These findings should encourage greater consideration of climate suitability when selecting release sites for conservation translocations and we advocate the use of SDMs as an effective way to do this.  相似文献   
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Fitzgerald, Evan P., William B. Bowden, Samuel P. Parker, and Michael L. Kline, 2012. Urban Impacts on Streams Are Scale‐Dependent with Nonlinear Influences on Their Physical and Biotic Recovery in Vermont, United States. Journal of the American Water Resources Association (JAWRA) 48(4): 679‐697. DOI: 10.1111/j.1752‐1688.2012.00639.x Abstract: The physical and biological conditions of stream reaches in 16 watersheds within the Lake Champlain Basin of Vermont, United States, were assessed and analyzed for a response to total impervious area (TIA) at multiple spatial scales. Natural gradients (e.g., channel slope) and human impacts to channel boundary conditions (e.g., bank armoring) were considered to ensure a robust test of the Impervious Cover Model for upslope TIA. The response of geomorphic stability and sensitive macroinvertebrates to TIA was nonlinear and significant (p < 0.001), decreasing rapidly at 5% TIA. The effect of urbanization on stream condition was shown to interact significantly with drainage area and channel slope using the analysis of covariance (ANCOVA) (p < 0.05). Hydraulic geometry regressions for urban and rural watersheds and ANCOVA were used to describe a significant watershed scale‐dependent response of channel width to urbanization (p = 0.001). The analysis of macroinvertebrate data from reaches in different stages of channel evolution indicated that stable reaches supported greater richness of pollution intolerant species (p < 0.001) and overall taxa richness (p < 0.01) than unstable reaches, and that biotic integrity improves as channels regain stability during their evolution into a state of quasi‐equilibrium. We conclude that macroinvertebrate communities can respond positively to channel evolution processes leading to natural channel restabilization.  相似文献   
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ABSTRACT

This study utilized a biotrickling filter with blast-furnace slag packings (sizes = 20-40 mm; specific surface area = 120 m2/m3) to treat toluene in an air stream. Also studied were the effects of volumetric loading (L), nutrient addition, and superficial gas velocity (Ug) or gas retention time on toluene elimination capacity. Experimental results indicate that, for a test period of 121 days, with no excess biomass removal, toluene removal efficiencies of over 90% were obtained with Ug < 80 m/hr and L < 30 g/m3.hr. For a test period of 49 days, with Ug < 80 m/hr and L increased from 1.2 to 81 g/m3.hr, the absence of nutrient supplementation did not limit the toluene elimination capacity. Nutrients stored in the biofilm could adequately support the microbial activity for the toluene elimination. According to data regression, a simplified mass-transfer model is proposed, which correlates the contaminant concentration with the packing height or gas empty bed retention time. As verified, the model proposed herein can be applied to cases involving low influent contaminant concentrations or loadings to the extent that none or only a trace amount of the contaminant can be found in the recirculation liquid. Although small media with larger specific surface areas can achieve a better mass transfer, the problems of frequent backwashing and relatively greater gas resistance in using this type of media probably outweigh the advantages, particularly for full-scale systems that would not be watched as closely as laboratory test systems.  相似文献   
146.
The electrodes in industrial precipitators collect many tons of dust daily, and the efficient transfer of this dust burden to the hoppers is a challenging problem in mechanical engineering. Many varieties of devices have been tried; hammers, vibrators, scrapers, water flushing, gas blasting, etc. Impact devices for this purpose are usually called “rappers.” Laboratory experiments described in this paper show that normal (perpendicular) rapping is more effective than shear rapping; that thick dust layers are more easily removed by rapping than thin ones; that rapping becomes easier with increasing temperature, within limits; and that the electrostatic forces acting upon the precipitated dust layer play an important role. Quantitative data are shown graphically. The relation of these results to previous studies by other investigators is discussed.  相似文献   
147.
A procedure is described for producing a sulfur dioxide (SO2) contaminated atmosphere within a body plethysmograph, exposing man to this atmosphere while maintaining the SO2 concentration at a given level, and measuring the concentration with less than a oneminute lag time. A syringe is used to introduce incremental volumes of SO2 limiting the maximum SO2 concentration in the chamber and assuring safety of the subject. A Titrilog SO2 analyzer with its rapid response characteristics provides quick measurement of the SO2 concentration. The body plethysmograph used in this manner serves simultaneously as a pulmonary function measuring device and as an exposure chamber.  相似文献   
148.
Urban tinkering     
Cities are currently experiencing serious, multifaceted impacts from global environmental change, especially climate change, and the degree to which they will need to cope with and adapt to such challenges will continue to increase. A complex systems approach inspired by evolutionary theory can inform strategies for policies and interventions to deal with growing urban vulnerabilities. Such an approach would guide the design of new (and redesign of existing) urban structures, while promoting innovative integration of grey, green and blue infrastructure in service of environmental and health objectives. Moreover, it would contribute to more flexible, effective policies for urban management and the use of urban space. Four decades ago, in a seminal paper in Science, the French evolutionary biologist and philosopher Francois Jacob noted that evolution differs significantly in its characteristic modes of action from processes that are designed and engineered de novo (Jacob in Science 196(4295):1161–1166, 1977). He labeled the evolutionary process “tinkering”, recognizing its foundation in the modification and molding of existing traits and forms, with occasional dramatic shifts in function in the context of changing conditions. This contrasts greatly with conventional engineering and design approaches that apply tailor-made materials and tools to achieve well-defined functions that are specified a priori. We here propose that urban tinkering is the application of evolutionary thinking to urban design, engineering, ecological restoration, management and governance. We define urban tinkering as:
A mode of operation, encompassing policy, planning and management processes, that seeks to transform the use of existing and design of new urban systems in ways that diversify their functions, anticipate new uses and enhance adaptability, to better meet the social, economic and ecological needs of cities under conditions of deep uncertainty about the future.
This approach has the potential to substantially complement and augment conventional urban development, replacing predictability, linearity and monofunctional design with anticipation of uncertainty and non-linearity and design for multiple, potentially shifting functions. Urban tinkering can function by promoting a diversity of small-scale urban experiments that, in aggregate, lead to large-scale often playful innovative solutions to the problems of sustainable development. Moreover, the tinkering approach is naturally suited to exploring multi-functional uses and approaches (e.g., bricolage) for new and existing urban structures and policies through collaborative engagement and analysis. It is thus well worth exploring as a means of delivering co-benefits for environment and human health and wellbeing. Indeed, urban tinkering has close ties to systems approaches, which often are recognized as critical to sustainable development. We believe this concept can help forge much-closer, much-needed ties among engineers, architects, evolutionary ecologists, health specialists, and numerous other urban stakeholders in developing innovative, widely beneficial solutions for society and contribute to successful implementation of SDG11 and the New Urban Agenda.
  相似文献   
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We use ensemble-mean Lagrangian sampling of a 3-D Eulerian air quality model, CMAQ, together with ground-based ambient monitors data from several air monitoring networks and satellite (MODIS) observations to provide source apportionment and regional transport vs. local contributions to sulfate aerosol and PM2.5 concentrations at Baltimore, MD, for summer 2004. The Lagrangian method provides estimates of the chemical and physical evolution of air arriving in the daytime boundary layer at Baltimore. Study results indicate a dominant role for regional transport contributions on those days when sulfate air pollution is highest in Baltimore, with a principal transport pathway from the Ohio River Valley (ORV) through southern Pennsylvania and Maryland, consistent with earlier studies. Thus, reductions in sulfur emissions from the ORV under the EPA's Clean Air Interstate Rule may be expected to improve particulate air quality in Baltimore during summer. The Lagrangian sampling of CMAQ offers an inexpensive and complimentary approach to traditional methods of source apportionment based on multivariate observational data analysis, and air quality model emissions separation. This study serves as a prototype for the method applied to Baltimore. EPA is establishing a system to allow air quality planners to readily produce and access equivalent results for locations of their choice.  相似文献   
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