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361.
A methodology for regional application of forest simulation models has been developed as part of an assessment of possible climate change impacts in the Federal state of Brandenburg (Germany). Here we report on the application of a forest gap model to analyse the impacts of climate change on species composition and productivity of natural and managed forests in Brandenburg using a statistical method for the development of climate scenarios. The forest model was linked to a GIS that includes soil and groundwater table maps, as well as gridded climate data with a resolution of 10 × 10 km and simulated a steady-state species composition which was classified into forest types based on the biomass distribution between species. Different climate scenarios were used to assess the sensitivity of species composition to climate change. The simulated forest distribution patterns for current climate were compared with a map of Potential Natural Vegetation (PNV) of Brandenburg.In order to analyse the possible consequences of climate change on forest management, we used forest inventory data to initialize the model with representative forest stands. Simulation experiments with two different management strategies indicated how forest management could respond to the projected impacts of climate change. The combination of regional analysis of natural forest dynamics under climate change with simulation experiments for managed forests outlines possible trends for the forest resources. The implications of the results are discussed, emphasizing the regional differences in environmental risks and the adaptation potentials of forestry in Brandenburg.  相似文献   
362.
Urban water infrastructure expenditures cause a major financial burden to municipalities. In the opinion of many policy-makers, public funds may alleviate this burden and facilitate environmental policies. However, practice has shown that despite ambitious policies, funding often follows traditional cost-dominated thinking. In Austria, national policy-makers were interested in new guidelines for funding that increase the transparency of the planning, ensure the adequate treatment of ecological problems, and foster stakeholder involvement, but keep the process as simple as possible, and require minimal changes of the current guidelines. An interdisciplinary project team conducted such a study. Its outcome was tested in two pilot projects. Based on these experiences, policy-makers finally implemented the recommended guidelines for the funding of communal urban water infrastructure projects. A general observation about the policy-making process was a conservative attitude of policy-makers. They prefer simple constraints (precautionary principle) and flexible negotiations (delegation) to complex assessment and decision-aid methodologies.  相似文献   
363.
Ohne Zusammenfassung Verantwortliche Herausgeber: Jan Schwarzbauer · Peter Heininger · Evelyn Claus
Henner Hollert (Corresponding author)Email:
Evelyn ClausEmail:
Peter HeiningerEmail:
Jan SchwarzbauerEmail:
  相似文献   
364.
Wetland productivity in the Prairie Pothole Region (PPR) of North America is closely linked to climate. A warmer and drier climate, as predicted, will negatively affect the productivity of PPR wetlands and the services they provide. The effect of climate change on wetland productivity, however, will not only depend on natural processes (e.g., evapotranspiration), but also on human responses. Agricultural land use, the predominant use in the PPR, is unlikely to remain static as climate change affects crop yields and prices. Land use in uplands surrounding wetlands will further affect wetland water budgets and hence wetland productivity. The net impact of climate change on wetland productivity will therefore depend on both the direct effects of climate change on wetlands and the indirect effects on upland land use. We examine the effect of climate change and land-use response on semipermanent wetland productivity by combining an economic model of agricultural land-use change with an ecological model of wetland dynamics. Our results suggest that the climate change scenarios evaluated are likely to have profound effects on land use in the North and South Dakota PPR, with wheat displacing other crops and pasture. The combined pressure of land-use and climate change significantly reduces wetland productivity. In a climate scenario with a +4 °C increase in temperature, our model predicts that almost the entire region may lack the wetland productivity necessary to support wetland-dependent species.  相似文献   
365.
Triclosan—the forgotten priority substance?   总被引:1,自引:0,他引:1  

Introduction  

Triclosan (TCS) is a multi-purpose biocide. Its wide use in personal care products (PCPs) fosters its dispersal in the aquatic environment. Despite enhanced awareness of both scientists and the public in the last decade with regard to fate and effects, TCS received little attention regarding its prioritisation as a candidate river basin-specific pollutant or even priority substance, due to scarce monitoring data.  相似文献   
366.
Substance-related monitoring is an essential tool within environmental risk assessment processes. The soundness of policy decisions including risk management measures is often directly related to the reliability of the environmental monitoring programs. In addition, monitoring programs are required for identifying new and less-investigated pollutants of concern in different environmental media. Scientifically sound and feasible monitoring concepts strongly depend on the aim of the study. The proper definition of questions to be answered is thus of pivotal importance. Decisions on sample handling, storage and the analysis of the samples are important steps for the elaboration of problem-oriented monitoring strategies. The same applies to the selection of the sampling sites as being representative for scenarios to be investigated. These steps may become critical to handle for larger international monitoring programs and thus trigger the quality of their results. This study based on the work of an IUPAC (International Union of Pure and Applied Chemistry) task group addresses different kinds and approaches of substance-related monitoring of different compartments of soil, groundwater and surface water, and discusses their advantages and limitations. Further important aspects are the monitoring across policies and the monitoring data management using information systems.  相似文献   
367.
Despite the fact that adverse health effects of asbestos have been known since shortly after the turn of the century,1 there has been little progress in techniques for determining the mineral in the airborne state. This absence of sampling and analysis methods appears to derive from two main sources: (1) In the environments of the asbestos using industries, asbestos concentrations tend to be high relative to other particulate species, and especially compared with other fibrous species, making estimation of concentration by microscopy relatively easy. (2) The term "asbestos" describes a crystal habit, not a chemical compound; therefore there is no unique chemical property of asbestos that can be used as the basis for its measurement. Interestingly, there appears to be no basis for distinguishing the health effects of one type of asbestos over another;2 the physiological response seems more dependent on crystal habit than on composition.  相似文献   
368.
Abstract

Although emission inventories are the foundation of air quality management and have supported substantial improvements in North American air quality, they have a number of shortcomings that can potentially lead to ineffective air quality management strategies. Major reductions in the largest emissions sources have made accurate inventories of previously minor sources much more important to the understanding and improvement of local air quality. Changes in manufacturing processes, industry types, vehicle technologies, and metropolitan infrastructure are occurring at an increasingly rapid pace, emphasizing the importance of inventories that reflect current conditions. New technologies for measuring source emissions and ambient pollutant concentrations, both at the point of emissions and from remote platforms, are providing novel approaches to collecting data for inventory developers. Advances in information technologies are allowing data to be shared more quickly, more easily, and processed and compared in novel ways that can speed the development of emission inventories. Approaches to improving quantitative measures of inventory uncertainty allow air quality management decisions to take into account the uncertainties associated with emissions estimates, providing more accurate projections of how well alternative strategies may work. This paper discusses applications of these technologies and techniques to improve the accuracy, timeliness, and completeness of emission inventories across North America and outlines a series of eight recommendations aimed at inventory developers and air quality management decision-makers to improve emission inventories and enable them to support effective air quality management decisions for the foreseeable future.  相似文献   
369.
Meinert C  Moeder M  Brack W 《Chemosphere》2007,70(2):215-223
A fractionation procedure for technical p-nonylphenol using preparative capillary gas chromatography (pcGC) was developed and evaluated for its potential applicability in effect-directed analysis (EDA). The instrument is composed of (1) a preparative unit equipped with a cold injection system (CIS), two preparative fraction collectors (PFCs) with six fraction traps each, and a flame ionization detector (FID) and (2) an analytical unit sharing the same GC oven and equipped with another CIS and mass spectrometric detection (MSD) for isomer identification. The pcGC methodology used in this study is characterized by a high reproducibility of retention times and peak areas. This provides the fractionation of nonylphenol isomers into 11 fractions containing 77-552microg of isomers collected after 600 single injections. This yield is sufficient to allow subsequent biotesting in the E-screen assay.  相似文献   
370.
The effect of free-air ozone fumigation and crown position on antioxidants were determined in old-growth spruce (Picea abies) trees in the seasonal course of two consecutive years (2003 and 2004). Levels of total ascorbate and its redox state in the apoplastic washing fluid (AWF) were increased under double ambient ozone concentrations (2xO3), whilst ascorbate concentrations in needle extracts were unchanged. Concentrations of apoplastic and symplastic ascorbate were significantly higher in 2003 compared to 2004 indicating a combined effect of the drought conditions in 2003 with enhanced ozone exposure. Elevated ozone had only weak effects on total glutathione levels in needle extracts, phloem exudates and xylem saps. Total and oxidised glutathione concentrations were higher in 2004 compared to 2003 and seemed to be more affected by enhanced ozone influx in the more humid year 2004 compared to the combined effect of elevated ozone and drought in 2003 as observed for ascorbate.  相似文献   
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