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叙述了MicrosoftWordforWindows软件在编写环境质量报告书中的应用内容。  相似文献   

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The aim of this study is to develop a catalytic method which has advantages over current method to detoxify and degrade environmentally harmful polychlorinated biphenyls (PCBs). A variety of catalysts have been employed in a preliminary study on 1,4-dibromobenzene and 4,4-dibromobiphenyl which may be considered to represent simple analogues of PCBs. The most satisfactory catalysts are those involving [Pd(dppf)] [dppf = 1,1-bis(diphenylphosphino)ferrocene], generated in situ from PdCl2(dppf) or Pd(dppf)2. In the presence of the reducing reagent, namely NaBH4, debromination has been achieved at relative mild conditions with high product yields (> 70%). Thus, our results indicate the possibility of dechlorination of PCBs with such catalysts.  相似文献   

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In the Netherlands the increasing demand for ecohydrological models on a regional (provincial) scale has resulted in the development of an empirical statistical impact–assessment model for semi-natural terrestrial herbaceous ecosystems. This model, called ITORS, describes the relationship between plant species and site factors such as soil, groundwater and management. The model, developed for the region of Noord-Holland, is applied to support provincial policy on soil and water management. The empirical statistical approach required the collection of a large set of field data, describing the biotic and environmental variation of a variety of semi-natural terrestrial ecosystems in Noord-Holland. These data were used to calculate species response models with help of logistic regression, resulting in significant models for 130 out of 144 species. Significant species response models were incorporated in the computer program ITORS. With help of ITORS the effect of various management scenarios can be easily evaluated, which is demonstrated by an example. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
Environmental Modeling & Assessment - Anthropogenic methane emission is the most important greenhouse gas, after CO2 emission. However, various aspects of methane emission have not been...  相似文献   

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As part of the U.S. 2003 National Report on Sustainable Forests, four metrics of forest fragmentation--patch size, edge amount, inter-patch distance, and patch contrast--were measured within 137744 non-overlapping 5625 ha analysis units on land-cover maps derived from satellite imagery for the 48 conterminous States. The perimeter of a typical forest patch is about 100 m from the perimeter of its nearest neighbor, except when there is not much forest, in which case that distance is 200 to 300 m. A typical analysis unit has from 10 to 40% as much forest edge as it could possibly have, given the amount of forest present. Most analysis units contain a large number of patches that are less than one hectare in size, and about 10% contain one or more 2000 to 5000 ha patches. Forest often defines the background landscape, and patch contrast is generally either very high or very low in eastern regions and intermediate in western regions. Many research needs were identified by this experimental analysis of available data and metrics.  相似文献   

8.
Practice and research in assessment of global environmental change are dominated by two conventional assessment methods, formal models and expert panels. Models construct a representation of biophysical and socioeconomic components of a policy issue, to project future trends or consequences of interventions. Panels articulate consensus views of policyrelevant knowledge through deliberations among selected experts. These methods make valuable contributions, but are weak in addressing certain kinds of knowledge needs that are typical of globalchange issues. To address these needs, a set of novel assessment methods is proposed that combine elements of representation and deliberation. These methods, of which policy exercises, simulationgaming, and scenario exercises are examples, involve human participants in structured relevant decision and task settings. Relative to models and panels, these methods can more readily incorporate diverse perspectives, can integrate across broader collections of knowledge domains, and can both encourage creative insights and innovations, and provide tests of their relevance and practicality. Risks of bias, and of overconfident generalization from unique experiences, are effectively mitigated by critical debriefings, and appear no more severe than corresponding risks in conventional assessment methods, or in policymakers generalizations from historical experience. While serious development and implementation challenges remain, early experience suggests that these methods can offer useful ideas and insights for policymaking that are not available through other means.  相似文献   

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In order to examine the condition of biota in Atlantic coast estuaries, "Contaminant Exposure and Effects—Terrestrial Vertebrates" database (CEE-TV) has been compiled through computerized search of published literature, review of existing databases, and solicitation of unpublished reports from conservation agencies, private groups, and universities. Summary information has been entered into the database, including species, collection date (1965–present), site coordinates, estuary name, hydrologic unit code, sample matrix, contaminant concentrations, biomarker and bioindicator responses, and reference source, utilizing a 98-field character and numeric format. Currently, the CEE-TV database contains 3699 geo-referenced records representing 190 vertebrate species and >140,000 individuals residing in estuaries from Maine through Florida. This relational database can be directly queried or imported into a Geographic Information System to examine spatial patterns, identify data gaps and areas of concern, generate hypotheses, and focus ecotoxicological field assessments. Information on birds made up the vast majority (83%) of the database, with only a modicum of data on amphibians (<0.1%). Of the >75,000 chemical compounds in commerce, only 118 commonly measured environmental contaminants were quantified in tissues of terrestrial vertebrates. There were no CEE-TV data records in 15 of the 67 estuaries located along the Atlantic coast and Florida Gulf coast. The CEE-TV database has a number of potential applications including focusing biomonitoring efforts to generate critically needed ecotoxicological data in the numerous "gaps" along the coast, reducing uncertainty about contaminant risk, identifying areas for mitigation, restoration or special management, and ranking ecological conditions of estuaries.  相似文献   

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Air pollutants pose a risk to forest health and vitality in the United States. Here we present the major findings from a national scale air pollution assessment that is part of the United States' 2003 Report on Sustainable Forests. We examine trends and the percent forest subjected to specific levels of ozone and wet deposition of sulfate, nitrate, and ammonium. Results are reported by Resource Planning Act (RPA) reporting region and integrated by forest type using multivariate clustering. Estimates of sulfate deposition for forested areas had decreasing trends (1994-2000) across RPA regions that were statistically significant for North and South RPA regions. Nitrate deposition rates were relatively constant for the 1994 to 2000 period, but the South RPA region had a statistically decreasing trend. The North and South RPA regions experienced the highest ammonium deposition rates and showed slightly decreasing trends. Ozone concentrations were highest in portions of the Pacific Coast RPA region and relatively high across much of the South RPA region. Both the South and Rocky Mountain RPA regions had an increasing trend in ozone exposure. Ozone-induced foliar injury to sensitive species was recorded in all regions except for the Rocky Mountain region. The multivariate analysis showed that the oak-hickory and loblolly-shortleaf pine forest types were generally exposed to more air pollution than other forest types, and the redwood, western white pine, and larch forest types were generally exposed to less. These findings offer a new approach to national air pollution assessments and are intended to help focus research and planning initiatives related to air pollution and forest health.  相似文献   

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A comparative Life Cycle Assessment (LCA) of solar photo-Fenton and solar photoelectro-Fenton, two solar-driven advanced oxidation processes (AOPs) devoted to the removal of non-biodegradable pollutants in water, is performed. The study is based on the removal, at laboratory scale, of the amino acid α-methylphenylglycine, a good example of soluble and non-biodegradable target pollutant. The system under study includes chemicals, electricity, transport of all raw materials to the plant site, and the generation of emissions, but it does not take into account the impact of the infrastructure needed to build a hypothetical solar plant. Nine environmental impact categories are included in the LCA: global warming potential, ozone depletion potential, aquatic eutrophication potential, acidification potential, human toxicity potential, photochemical ozone formation potential, fresh water aquatic ecotoxicity potential, marine aquatic ecotoxicity potential, and terrestrial ecotoxicity potential and abiotic resource depletion potential. Although previous experimental results show that both AOPs are able to efficiently degrade the pollutant, the LCA indicates that solar-driven photo-Fenton is the most environmentally friendly alternative, mainly because the use of electricity in solar photoelectro-Fenton experiments involves high environmental impacts.  相似文献   

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Environmental benchmarks are widely used in Canadian environmental assessment as a standard against which to monitor air or water quality in response to human activities in the environment. Recent work in Canada has developed the concept of ecological benchmarks as a complement to environmental benchmarks. However, implementation of ecological benchmarks may be challenging. This paper presents an analogy between ecological benchmarks and the more commonly used environmental benchmarks, as an attempt to increase understanding and use of ecological benchmarks in resource management, assessment, and monitoring. Ecological benchmarks, and their corresponding indicators, will be challenging to identify and use. However, through the use of the principles of adaptive management, effective ecological indicators and benchmarks can be established. Although it is essential that ecological benchmarks are site-specific, the analogy and general principles outlined here are applicable to assessment and monitoring in any part of the world.  相似文献   

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Nitrogen leaching is a world-wide concern for the quality of ground- and surfacewater. Measures to abate this is still limited by a lack of understanding mechanisms behind all factors describing the leaching process, time lags between countermeasures and improvement in waterquality and spatial distribution of nitrogen leaching. The purpose of this study was to do an initial test of the SOILNDB model system which is built on the existing mechanistic SOIL and SOILN models and an automatic parameterization procedure for use of simplified input data. The test was done by simulating nitrogen leaching from each of the 150 fields in a small catchment during a three-year study period. The simulated mean root-zone nitrogen leaching rate from all the fields in the catchment was compared to measurements of nitrogen flow in the stream draining the catchment and showed good agreement in between-year dynamics.  相似文献   

14.
In May 2008 a coastal landslide deposited landfill debris onto the shore near Lyme Regis, UK. Six months later, intertidal sediments and biota from the area were sampled to determine whether the landslip had affected distribution and bioavailability of metals in the area and if there were any biological effects. Highest sediment concentrations for the majority of metals occurred near the landslip zone and in several cases exceeded Threshold Effects or Probable Effects Levels (As, Cu, Hg, Ni, Pb, Zn). The 1 M HCl-extractable fraction of Cd, Pb and Zn in sediments also increased near the landslip. Metal bioaccumulation by intertidal biota showed variability between different species and metals, but there were several instances of increased accumulation near the landslip through increased availability from seawater, sediment and dietary sources. In most cases, metal concentrations in molluscs exceeded Oslo and Paris Commission (OSPAR) background concentrations (BCs) together with background assessment concentrations (BACs) at some sites. Kidney tissues in winkles (Littorina littorea) were measured for evidence of oxidative stress using the Total Oxyradical Scavenging Capacity (TOSC) assay. Responses to peroxynitrite, peroxyl and hydroxyl radicals suggested raised levels of TOSC in animals from the sites close to or east of the landfill waste. There have been very few studies of direct impact of landfills on the marine environment and this study could serve as a practical model for similar events driven by sea level rise.  相似文献   

15.
The study involves the Çe?me?CUrla Peninsula, where habitat fragmentation and loss, which threaten biological diversity, have become an urgent matter of concern in recent decades. The study area has been subjected to anthropogenic pressures and alterations due to ongoing and impending land uses. Therefore, ecological networks, as an appropriate way to deal with habitat fragmentation and loss and to improve ecological quality, were identified in the study area as one of the early attempts in the country to maintain its rich biodiversity. In this sense, core areas and ecological linkages as primary components of ecological networks were established on the basis of sustaining natural habitats. A GIS-based model was created to identify core areas and to facilitate the ecological connectivity. The modeling process for core areas and corridors combined 14 and 21 different variables, respectively. The variables were used as environmental inputs in the model, and all analyses were materialized in ArcGIS 9.2 using grid functions of image analysis and spatial analyst modules. As a result, six core areas and 36 corridor alternatives were materialized. Furthermore, some recommendations for the implementation and management of the proposed ecological networks were revealed and discussed.  相似文献   

16.
Performance evaluation of two reverse osmosis (RO) desalination plants (DSP) at villages: Melasirupodhu (30 m3 day-1) and Sikkal (50 m3 day-1) in Ramanathpuram district,Tamil Nadu (India) were studied so as to bring out the state-of-art of their operation and maintenance (O&M). Detailedinformation on plant design and engineering, water quality,plant personnel, and cost of O&M was collected for a period ofthree years after commissioning of the two plants. Feed waterwas brackish, the TDS varied in the range of 6500–8500 mg L-1 at Melasirupodhu and 5300–7100 mg L-1 atSikkal villages. The product water quality was observed to begradually deteriorating as the salt rejection by the membranesdecreased with time. The salt rejection was 97–99% atthe time of commissioning of the plants, and came down to89–90% at the end of 3 years of operation. Product water TDS soonafter installation of the plants was excellent and within desirable limits of BIS. After three years of operation, few parameters exceeded the desirable limits, however, they were found to be within permissible limits of BIS. The analyses of thedata showed that both plants were operated only at 30–36% of the design capacity. Plant shut-down due to inadequate and erratic power supply, and plant break-down and inherent delay in repairs due to lack of adequate infrastructure were found tobe the major causes for the low utilization of the plants. Consequently the recurring cost of product water production enhanced to Rs. 25.0/m3 at Melasirupodhu and Rs. 17.5 m-3 at Sikkal, as against the estimated cost of Rs. 15.0/m3 and Rs. 11.0/m3, respectively, as per the design. Over the years, the energy consumption for the product water output increased reflecting higher operational pressures needed with the aging of the membranes.  相似文献   

17.
A model is developed to predict annual and total above-ground carbon storage within a hybrid poplar stream buffer. The regression model predicts tree wet weight based upon circumference at breast-height (137 cm) with an r-square value of 0.9922. Carbon storage in above-ground biomass is estimated to be 3.57 to 3.71 metric tons per hectare, with a measured annual increment of 0.92 to 1.37 metric ton per hectare per year. The variability of carbon storage within this biological system, including soil organic matter, is explored, and the number of samples required to achieve a desired level of statistical certainty are predicted. As has been investigated previously for other biological systems (Garten and Wullschleger, 1999), the study shows that a prohibitively large number of samples must be taken in order to achieve high degrees of certainty about mean carbon storage values. The study also shows, however, that mean values with somewhat greater uncertainties can easily be achieved with much smaller sample sizes. Thus carbon sequestration verification might be accomplished cost-effectively if the degree of certainty required is not unrealistically high for highly variable natural systems.  相似文献   

18.
China is committed to peaking its carbon emissions by 2030 and become a carbon-neutral society by 2060. The building sector that accounts for over one-third of the total carbon emissions is expected to face a great challenge in helping China achieve this goal. Shenzhen, as a low-carbon pilot city, whether its low-carbon work of urban buildings reaches the target is crucial. An attempt has been made in this study to assess the intensity of carbon emissions and associated reduction efficiency of urban buildings (operation stage) in Shenzhen by using the life cycle assessment method. The results show that the total carbon emissions generated from the buildings' operation stage have increased from 22 million metric tons (Mt) CO2eq in 2005 to 42 (±13%) Mt. CO2eq in 2019. Carbon emissions mainly result from the buildings' electricity use (79%), followed by refrigerant release emissions (12%). The energy conservation and carbon emissions reduction intensity in Shenzhen is at the middle level in China, and there is considerable space for improvement. According to scenario-based analysis, the carbon emission of the buildings sector can probably reach its peak by 2025 with the implementation of suitable policies – 5 years earlier than national target by 2030. Overall, this study makes a systemic analysis of the characteristics of urban buildings energy consumption and carbon emissions reduction, which can provide supportings for justifying the effectiveness of low-carbon activities in Shenzhen and beyond.  相似文献   

19.
There is little information on exposure of marine mammals to genotoxic environmental contaminants. The 32P-postlabeling assay has been successfully used to assess exposure to genotoxic polycyclic aromatic compounds in fish and humans. In the present study, a preliminary investigation showed that polycyclic aromatic compound-like DNA adducts were present in hepatic tissues of harbor seals (Phoca vitulina richardsi) exposed to petroleum following the Exxon Valdez oil spill. However, for marine mammals, effects from changes in tissue condition on DNA recovery and quality is of concern, because tissue samples are often collected from animals that have been dead for unknown periods of time. To assess the effects of postmortem thermal history on DNA recovery from tissue and on DNA adduct quantitation, samples of harbor porpoise (Phocoena phocoena) hepatic tissue were incubated for up to 10 d at 4 and 30 °C. Only traces (<4 g) of hepatic DNA were recovered from 200 mg of tissue after incubation at 30 °C for 36 h. At 4 °C, DNA (50–130 g) was recovered from tissue incubated for up to 6 d; whereas DNA recovery at 10 d was minimal. Chromatograms of 32P-labeled DNA digests of liver tissue held at 4 and 30 °C and salmon sperm DNA held at 30 °C for 2 d had comparable profiles, suggesting that alteration of DNA bases had occurred during incubation of porpoise liver tissue. Moreover, the chromatograms of DNA extracted from liver tissues of harbor porpoises caught incidentally in a northwest Atlantic fishery, packed in ice and sampled several days later also exhibited similar altered DNA structures. Although, altered DNA structures that can interfere with the DNA adduct quantitation were present in autolyzed tissue, changes in the 32P-postlabeling chromatography conditions can decrease the interference. Moreover, in a study with tissues taken from California sea lions (Zalophus californianus) immediately postmortem and stored at –80 °C until processing, DNA structures associated with tissue breakdown were not observed. The DNA from sea lions, however, had putative age-dependent hepatic DNA modifications, which have a distinctive profile, and must be considered when evaluating exposure of marine mammals to polycyclic aromatic compounds. Overall, the findings showed that with attention to the postmortem thermal history of the tissue samples hepatic DNA adducts, as measured by 32P-postlabeling, have the potential to serve as a biological indicator of exposure of marine mammals to environmental genotoxic compounds.  相似文献   

20.
China's EIA Law does not require transboundary proposals to be assessed, despite recognition of this globally, for example in the Espoo Convention and Kiev Protocol, and in the European EIA and SEA Directives. In a transboundary context assessment within a state is unusual, as regulating these effects is primarily about the relationship between states. However where a state has more than one legal system such as in the Pearl River Delta (PRD) Region of southern China, transboundary effects should also be addressed. Yet despite the geographical connections between Guangdong Province in mainland China (where the EIA Law applies) and the Hong Kong and Macau Special Administrative Regions (which have their own provisions, neither of which requires transboundary assessments), EIA and SEA are carried out separately. Coordinated or joint approaches to transboundary assessment are generally absent, with the legal autonomy of Hong Kong and Macau a major constraint. As a result institutional responses at the policy level have developed. The article considers global experiences with regulating transboundary EIA and SEA, and analyses potential application to land use, transport and air and water planning in the PRD Region. If applied, benefits may include prevention or mitigation of cumulative effects, broader public participation, and improvements to environmental governance. The PRD Region experience may encourage China to conduct and coordinate EIA and SEA processes with neighbouring states, which has been non-existent or extremely limited to date.  相似文献   

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