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951.
We developed an assessment model to quantify the wildlife habitat value of New England salt marshes based on marsh characteristics and the presence of habitat types that influence habitat use by terrestrial wildlife. Applying the model to 12 salt marshes located in Narragansett Bay, RI resulted in assessment scores that ranged over a factor of 1.5 from lowest to highest. Pre-classifying the results based on marsh size and morphology helped to compare assessment scores between marshes, and demonstrated that even the lower ranking marshes had substantial habitat value. Stepwise multiple regression analysis of assessment scores and model components demonstrated that salt marsh morphology, the degree of anthropogenic modification, and salt marsh vegetative heterogeneity were significant variables and accounted for 91.3% of the variability in component scores. Our results suggest that targeting these components for restoration may lead to improved assessment scores for our study marshes. We also examined the use of lower resolution remote sensing data in the assessment in order to minimize the time and effort required to complete the model. Scores obtained using smaller-scale, lower resolution data were significantly lower than those obtained using larger-scale, higher resolution data (df = 11; t = 2.2; p < 0.001). The difference was significantly positively correlated with the portion of the assessment score that could be attributed to trees, pools, and pannes and marsh size (r (2) =0.50, F = 4.6, p = 0.04), and could indicate a bias against smaller, more heterogeneous marshes. We conclude that potential differences need to be weighed against the time benefit of using this type of data, bearing in mind the marsh size and the goals of the assessment. Overall, our assessment can provide information to aid in prioritizing marshes for protection and restoration, identify marshes that may harbor significant biodiversity, or help monitor changes in habitat value over time. 相似文献
952.
John P. Bucci Michelle D. Shattuck Semra A. Aytur Richard Carey William H. McDowell 《Environmental monitoring and assessment》2017,189(8):406
Water quality impairment by fecal waste in coastal watersheds is a public health issue. The present study provided evidence for the use of a mitochondrial (mtDNA) marker to detect animal fecal sources in surface water. The accurate identification of fecal pollution is based on the notion that fecal microorganisms preferentially inhabit a host animal’s gut environment. In contrast, mtDNA host-specific markers are inherent to eukaryotic host cells, which offers the advantage by detecting DNA from the host rather than its fecal bacteria. The present study focused on sampling water presumably from non-point sources (NPS), which can increase bacterial and nitrogen concentrations to receiving water bodies. Stream sampling sites located within the Piscataqua River Watershed (PRW), New Hampshire, USA, were sampled from a range of sites that experienced nitrogen inputs such as sewer and septic systems and suburban runoff. Three mitochondrial (mtDNA) gene marker assays (human, bovine, and canine) were tested from surface water. Nineteen sites were sampled during an 18-month period. Analyses of the combined single and multiplex assay results showed that the proportion of occurrence was highest for bovine (15.6%; n = 77) compared to canine (5.6%; n = 70) and human (5.7%; n = 107) mtDNA gene markers. For the human mtDNA marker, there was a statistically significant relationship between presence vs. absence and land use (Fisher’s test p = 0.0031). This result was evident particularly for rural suburban septic, which showed the highest proportion of presence (19.2%) compared to the urban sewered (3.3%), suburban sewered (0%), and agricultural (0%) as well as forested septic (0%) sites. Although further testing across varied land use is needed, our study provides evidence for using the mtDNA marker in large watersheds. 相似文献
953.
Sophie?GourguetEmail author Olivier?Thébaud Sarah?Jennings L.?Richard?Little Catherine?M.?Dichmont Sean?Pascoe Roy?A.?Deng Luc?Doyen 《Environmental Modeling and Assessment》2016,21(3):371-389
Fisheries management must address multiple, often conflicting objectives in a highly uncertain context. In particular, while the bio-economic performance of trawl fisheries is subject to high levels of biological and economic uncertainty, the impact of trawling on broader biodiversity is also a major concern for their management. The purpose of this study is to propose an analytical framework to formally assess the trade-offs associated with balancing biological, economic and non-target species conservation objectives. We use the Australian Northern Prawn Fishery (NPF), which is one of the most valuable federally managed commercial fisheries in Australia, as a case study. We develop a stochastic co-viability assessment of the fishery under multiple management objectives. Results show that, due to the variability in the interactions between the fishery and the ecosystem, current management strategies are characterized by biological and economic risks. Results highlight the trade-offs between respecting biological, economic and non-target species conservation constraints at each point in time with a high probability and maximizing the net present value of the fishery. 相似文献
954.
Patrick Mwendwa 《中国人口.资源与环境(英文版)》2012,10(1):73-79
The aim of this paper is to illustrate the benefits,and challenges towards providing multifunctional urban green spaces.The results are based on critical analysis of study findings from different cities in Europe,America and to a lesser extent in Asia.Inner-city green spaces are especially important for improving air quality through uptake of pollutant gases and particulates which are responsible for respiratory infections.Due to their amenity and aesthetics,green spaces increase property value.To ensure multifunctional role of urban a green space is achieved,in particular the social and psychological role,certain standards of quantity,quality and distribution within the urban area should be adequately established.Green spaces need to be uniformly distributed throughout the city area,although each does not need to be extremely large but should be large enough to accommodate the city population. 相似文献
955.
The United Kingdom uses the Defence Lines of Development (DLOD) framework to analyse and understand the key components and costs of a military capability. Rooted in the Resource Based View (RBV) of a firm, an adapted DLOD approach is employed to explore, analyse and discuss the preparedness, planning and response strategies of two markedly different countries (Australia and Bangladesh) when faced with a major cyclone event of a comparable size. Given the numerous similarities in the challenges facing military forces in a complex emergency and humanitarian agencies in a natural disaster, the paper demonstrates the applicability of the DLOD framework as an analysis and planning tool in the cyclone preparedness planning and response phases, and more broadly within the disaster management area. In addition, the paper highlights the benefit to disaster managers, policymakers and researchers of exploiting comparative cross-learning opportunities from disaster events, drawn from different sectors and countries. 相似文献
956.
Kinsey JS Timko MT Herndon SC Wood EC Yu Z Miake-Lye RC Lobo P Whitefield P Hagen D Wey C Anderson BE Beyersdorf AJ Hudgins CH Thornhill KL Winstead E Howard R Bulzan DI Tacina KB Knighton WB 《Journal of the Air & Waste Management Association (1995)》2012,62(4):420-430
The emissions from a Garrett-AiResearch (now Honeywell) Model GTCP85-98CK auxiliary power unit (APU) were determined as part of the National Aeronautics and Space Administration's (NASA's) Alternative Aviation Fuel Experiment (AAFEX) using both JP-8 and a coal-derived Fischer Tropsch fuel (FT-2). Measurements were conducted by multiple research organizations for sulfur dioxide (SO2, total hydrocarbons (THC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), speciated gas-phase emissions, particulate matter (PM) mass and number, black carbon, and speciated PM. In addition, particle size distribution (PSD), number-based geometric mean particle diameter (GMD), and smoke number were also determined from the data collected. The results of the research showed PM mass emission indices (EIs) in the range of 20 to 700 mg/kg fuel and PM number EIs ranging from 0.5 x 10(15) to 5 x 10(15) particles/kg fuel depending on engine load and fuel type. In addition, significant reductions in both the SO2 and PM EIs were observed for the use of the FT fuel. These reductions were on the order of approximately 90% for SO2 and particle mass EIs and approximately 60% for the particle number EI, with similar decreases observed for black carbon. Also, the size of the particles generated by JP-8 combustion are noticeably larger than those emitted by the APU burning the FT fuel with the geometric mean diameters ranging from 20 to 50 nm depending on engine load and fuel type. Finally, both particle-bound sulfate and organics were reduced during FT-2 combustion. The PM sulfate was reduced by nearly 100% due to lack of sulfur in the fuel, with the PM organics reduced by a factor of approximately 5 as compared with JP-8. 相似文献
957.
Craig A. Fitzner John C. Schroeder Richard F. Olson Paul M. Tatreau 《Journal of the Air & Waste Management Association (1995)》2013,63(5):727-728
The U.S. Environmental Protection Agency (EPA), in cooperation with the Toronto Harbour Commissioners (THC), conducted a Superfund Innovative Technology Evaluation (SITE) demonstration of the THC Soil Recycle Treatment Train. The treatment train consists of three technologies operated in sequence: a soil wash process, a metals removal process, and a biological treatment process. The THC conducted an extensive demonstration of the treatment train at a 55 tons per day pilot plant in order to evaluate an approach for remediation of industrial/commercial sites that are situated in the Toronto Port Industrial District (PID). Three soils were processed during the THC demonstration. The EPA SITE demonstration project examined, in detail, soil processing from one of the sites being evaluated as part of the overall THC project. Contaminants included organic compounds and heavy metals. It has been estimated by THC that as much as 2,200,000 tons of soil from locations within the PID may require some form of treatment due to heavy metal and/or organic contamination that resulted from various industrial processing operations. The objective of the SITE demonstration was to evaluate the technical effectiveness of the process in relation to THC’s target criteria. Gravel and sand that met the THC target criteria for medium to fine soil suitable for industrial/commercial sites was produced. The fine soil from the biological treatment process did not meet the target level of 2.4 ppm for benzo(a)pyrene. However, there was a significant reduction in polynuclear aromatic hydrocarbon (PAH) compounds. The metals removal process achieved reductions of greater than seventy percent for copper, lead, nickel, and zinc. 相似文献
958.
959.
James H. Turner Andrew S. Viner Richard E. Jenkins William M. Vatavuk John D. McKenna 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1105-1112
This is the second of a two-part article that reviews baghouse filtration theory, presents size estimating methods, and gives costing procedures for a variety of baghouse types and sizes. Part I of the article discussed theory and sizing; this part presents costing. Information is given for estimating total capital investment including separate costs for the bare baghouse (five types), bags, and, where needed, cages and Venturis. Factors are given for installation and for indirect costs. Direct and indirect annual costs are discussed. An example problem is given. The material in this article is taken primarily from the EAB Control Cost Manual. 相似文献
960.
Thomas R. Dittrich C. Richard Cothern 《Journal of the Air & Waste Management Association (1995)》2013,63(11):716-719
Trace metals collected on filter paper by a hi-volume air sampler for 24 hours were analyzed using the X-ray fluorescence method. A gamma ray exciting source (241Am) and a bremsstrahlung exciting source (147Pm) were both used to produce the X-rays, the latter being more efficient. For the samples collected in Dayton, several metals were detected, viz.: Ti, Fe, Cu, Zn, Pb, Cd, and Sn. Elements in the periodic table between Ti and Cs were seen to have a sensitivity limit of 0.5 micrograms/m3 of air. 相似文献