当地资源管理中多学科冲突分析和冲突减缓

在瑞典的研究项目"海岸带可持续管理"中,迄今已完成了几项冲突研究.鉴于这些研究的详细结果是分别发表的,本文综述这些冲突研究的重要成果,以及总结和概要讨论海岸带可持续管理资源和冲突研究的方法和主要成果.在关于环境和资源利用冲突的多学科和理论上分析以后,提出了海岸带可持续管理中所使用的方法,即相关利益方和冲突的结合分析.可归纳为以下主要4点:①绘制诸利益相关者及其利益图;②分析所有冲突;③研制减缓冲突和与利益相关者合作的方法;④把这些内容综合到一个系统之下,以便进行自然资源管理.在瑞典东、西海岸已经开展了一些资源利用冲突的范例研究,包括沿岸渔业、贻贝养殖、海岸带规划及具体的冲突,例如种群保护(海豹)和沿岸渔业之间冲突.研究人员既作为专家也作为冲突当事方参与.在冲突研究中,科学家作为利益相关者其作用值得特别注意.冲突管理不仅是为了解决目前的冲突,而且还作为资源综合管理系统的一部分,其中可开展知识转让;建立制度;科学、政治和行政等部门共同学习;以及科学家和资源用户之间合作.     

Soil criteria to protect terrestrial wildlife and open-range livestock from metal toxicity at mining sites

Thousands of hard rock mines exist in the western USA and in other parts of the world as a result of historic and current gold, silver, lead, and mercury mining. Many of these sites in the USA are on public lands. Typical mine waste associated with these sites are tailings and waste rock dumps that may be used by wildlife and open-range livestock. This report provides wildlife screening criteria levels for metals in soil and mine waste to evaluate risk and to determine the need for site-specific risk assessment, remediation, or a change in management practices. The screening levels are calculated from toxicity reference values based on maximum tolerable levels of metals in feed, on soil and plant ingestion rates, and on soil to plant uptake factors for a variety of receptors. The metals chosen for this report are common toxic metals found at mining sites: arsenic, cadmium, copper, lead, mercury, and zinc. The resulting soil screening values are well above those developed by the US Environmental Protection Agency. The difference in values was mainly a result of using toxicity reference values that were more specific to the receptors addressed rather than the most sensitive receptor.     

Strontium isotope study of coal utilization by-products interacting with environmental waters

Sequential leaching experiments on coal utilization by-products (CUB) were coupled with chemical and strontium (Sr) isotopic analyses to better understand the influence of coal type and combustion processes on CUB properties and the release of elements during interaction with environmental waters during disposal. Class C fly ash tended to release the highest quantity of minor and trace elements-including alkaline earth elements, sodium, chromium, copper, manganese, lead, titanium, and zinc-during sequential extraction, with bottom ash yielding the lowest. Strontium isotope ratios ((87)Sr/(86)Sr) in bulk-CUB samples (total dissolution of CUB) are generally higher in class F ash than in class C ash. Bulk-CUB ratios appear to be controlled by the geologic source of the mineral matter in the feed coal, and by Sr added during desulfurization treatments. Leachates of the CUB generally have Sr isotope ratios that are different than the bulk value, demonstrating that Sr was not isotopically homogenized during combustion. Variations in the Sr isotopic composition of CUB leachates were correlated with mobility of several major and trace elements; the data suggest that arsenic and lead are held in phases that contain the more radiogenic (high-(87)Sr/(86)Sr) component. A changing Sr isotope ratio of CUB-interacting waters in a disposal environment could forecast the release of certain strongly bound elements of environmental concern. This study lays the groundwork for the application of Sr isotopes as an environmental tracer for CUB-water interaction.     

Evaluation of a detailed model of secondary organic aerosol formation from α-pinene against dark ozonolysis experiments

BOREAM, a detailed model for the gas-phase oxidation of α-pinene and its subsequent formation of Secondary Organic Aerosol (SOA), is tested against a large set of SOA yield measurements obtained in dark ozonolysis experiments. For the majority of experiments, modelled SOA yields are found to agree with measured yields to within a factor 2. However, the comparisons point to a general underestimation of modelled SOA yields at high temperatures (above 30 °C), reaching an order of magnitude or more in the worst cases, whereas modelled SOA yields are often overestimated at lower temperature (by a factor of about 2). Comparisons of results obtained using four different vapour pressure prediction methods indicate a strong sensitivity to the choice of the method, although the overestimated temperature dependence of the yields is found in all cases. Accounting for non-ideality of the aerosol mixture (based on an adapted UNIFAC method) has significant effects, especially at low yields. Our simulations show that the formation of oligomers through the gas-phase reactions of Stabilised Criegee Intermediates (SCI) with other molecular organic products could increase the SOA yield significantly only at very low relative humidity (below 1%). Further tests show that the agreement between model and measurements is improved when the ozonolysis mechanism includes additional production of non-volatile compounds.     

Denitrification in nitrate-rich streams: application of N2:Ar and 15N-tracer methods in intact cores.

Rates of benthic denitrification were measured using two techniques, membrane inlet mass spectrometry (MIMS) and isotope ratio mass spectrometry (IRMS), applied to sediment cores from two NO3(-)-rich streams draining agricultural land in the upper Mississippi River Basin. Denitrification was estimated simultaneously from measurements of N2:Ar (MIMS) and 15N[N2] (IRMS) after the addition of low-level 15NO3- tracer (15N:N = 0.03-0.08) in stream water overlying intact sediment cores. Denitrification rates ranged from about 0 to 4400 micromol N x m(-2) x h(-1) in Sugar Creek and from 0 to 1300 micromol N x m(-2) x h(-1) in Iroquois River, the latter of which possesses greater streamflow discharge and a more homogeneous streambed and water column. Within the uncertainties of the two techniques, there is good agreement between the MIMS and IRMS results, which indicates that the production of N2 by the coupled process of nitrification/denitrification was relatively unimportant and surface-water NO3- was the dominant source of NO3- for benthic denitrification in these streams. Variation in stream NO3- concentration (from about 20 micromol/L during low discharge to 1000 micromol/L during high discharge) was a significant control of benthic denitrification rates, judging from the more abundant MIMS data. The interpretation that NO3- concentration directly affects denitrification rate was corroborated by increased rates of denitrification in cores amended with NO3-. Denitrification in Sugar Creek removed < or = 11% per day of the instream NO3- in late spring and removed roughly 15-20% in late summer. The fraction of NO3- removed in Iroquois River was less than that of Sugar Creek. Although benthic denitrification rates were relatively high during periods of high stream flow, when NO3 concentrations were also high, the increase in benthic denitrification could not compensate for the much larger increase in stream NO3- fluxes during high flow. Consequently, fractional NO3- losses were relatively low during high flow.     

Linking Water Science to Policy: Results from a Series of National Workshops on Water

To ensure science better informs the decision-making process, researchers and policy/program managers need to understand and respect each other's way of working, culture and operational timelines. However, there is little practical guidance on how this should be done and even less documented experience with specific mechanisms that better link these two groups. The published literature on information transfer has largely emphasized the dissemination of standard packages of information to ill-defined constituencies whose needs for scientific information are not well understood. Environment Canada's National Water Research Institute, on behalf of the Canadian Council of Ministers of the Environment, led a series of “Linking Water Science to Policy Workshops” as one such mechanism by which recent science could be delivered to practitioners, and practitioners could identify their research needs to scientists and research managers. There is a pressing need to explore and share experiences using creative mechanisms for sustained dialogue and networking between scientists and policy and program managers. The lessons learned from the workshop series and the need for science to continually inform the decision-making process has particular relevance for Canada's Ecosystem Initiatives given their integrated, place-based focus on long-term restoration and protection, and the challenge of continually changing ecosystems.The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

Assessing Landscape Condition Relative to Water Resources in the Western United States: A Strategic Approach

The Environmental Monitoring and Assessment Program (EMAP) is proposing an ambitious agenda to assess the status of streams and estuaries in a 12-State area of the western United States by the end of 2003. Additionally, EMAP is proposing to access landscape conditions as they relate to stream and estuary conditions across the west. The goal of this landscape project is to develop a landscape model that can be used to identify the relative risks of streams and estuaries to potential declines due to watershed-scale, landscape conditions across the west. To do so, requires an understanding of quantitative relationships between landscape composition and pattern metrics and parameters of stream and estuary conditions. This paper describes a strategic approach for evaluating the degree to which landscape composition and pattern influence stream and estuary condition, and the development and implementation of a spatially-distributed, landscape analysis approach.