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141.
- Dedicated to Prof. Dr. Ulrich Förstner on his 65th birthdayBackground, Aims and Scope The main challenge in the application of biotests for hazard assessment of sediments is a transparent interpretation, especially if combinations of biotests are applied and an integrated assessment of all results is wanted. For decision making, assigning results of biotesting into different classes that indicate increasing hazards can be a useful tool. In this paper we suggest an approach on how to set up a site-independent classification system for sediment toxicity tests.Methods About 250 sediment samples were collected from two rivers and evaluated. The bioassays applied are used in a standardized procedure for all samples over years. The test battery include toxicological endpoints like nematode growth and reproduction, algae growth, bacteria activity, and luminescence inhibition.Results and Discussion The classification system described emphasizes the following steps: the assessment of test-specific response spans for each applied biotest and the subsequent interpretation of inhibition values in terms of toxicity, estimation of accuracy and uncertainty of different test systems, and the use of cluster- and k-means analyses in order to identify occurring pattern within a large biotest data base, followed by a ranking. The outcome of the procedure were 5 effect classes with an increasing potential of hazard. Conclusion The effect classes represent the result of a logical procedure of deduction. The procedure is transparent giving an increased degree of certainty. The site independent ranking of 5 classes could be used for sediment monitoring and facilitate fast interpretation. Recommendation and Perspective A large database comprising differently contaminated sediments is the precondition for setting up effect classes, because it is essential to know the range of effects and the variability of the test methods. The proposed procedure could then provide the basic rules for designing an expert system. 相似文献
142.
How does forest certification contribute to boreal biodiversity conservation? Standards and outcomes in Sweden and NW Russia 总被引:2,自引:0,他引:2
Marine Elbakidze Per AngelstamKjell Andersson Mats NordbergYurij Pautov 《Forest Ecology and Management》2011,262(11):1983-1995
Forest Stewardship Council (FSC) is one of the leading forest certification schemes. While many studies concern political aspects and social outcomes of FSC, little is known about the contribution of certification to biodiversity conservation. In Europe, the Russian Federation and Sweden have the largest areas of FSC-certified forest. We assessed the potential of FSC certification for boreal biodiversity conservation in terms of standard content, and outcomes as habitat area set aside and habitat network functionality. First, we compared the biodiversity conservation indicators at different spatial scales in Swedish and Russian FSC standards. Second, focusing on one large state forest management unit in each country, we compared the areas of formally and voluntarily set aside forests for biodiversity conservation. Third, we evaluated the structural habitat connectivity by applying morphological spatial pattern analysis, and potential functional connectivity by using habitat suitability index modelling for virtual species. The Russian standard included indicators for all spatial scales of biodiversity conservation, from tree and stand to landscape and ecoregions. The Swedish standard focused mainly on stand and tree scales. The area of voluntary set-asides for FSC was similar in Sweden and Russia, while formal protection in the Russian case study was three times higher than in the Swedish one. Swedish set-aside core areas were two orders of magnitude smaller, had much lower structural and potential functional connectivity and were located in a fragmented forestland holding. We conclude that to understand the potential of FSC certification for biodiversity conservation both the standard content, and its implementation on the ground, need to be assessed. We discuss the potential of FSC certification for biodiversity conservation with different levels of ambition. We stress the need for developing rapid assessment tools to evaluate outcomes of FSC for biodiversity conservation on the ground, which could be used by forest managers and FSC-auditors toward adaptive governance and management. 相似文献
143.
广西水耕人为土黏粒矿物组成及其空间分布特征 总被引:1,自引:1,他引:0
黏粒矿物影响着土壤理化性质,可指示成土因素特征和土壤发生发育过程/强度,也是中国土壤系统分类的基层单元土族矿物学类型划分的重要依据。本研究选择了广西不同纬度和成土母质的18个代表性水耕人为土的剖面,应用X射线衍射(XRD)方法分析了其典型水耕氧化还原层(Br层)的黏粒矿物组成及其空间分布特征,并确定了其中"黏质"剖面的土族控制层段矿物学类型。结果表明:①供试土壤的黏粒矿物主要包括高岭石、伊利石、三水铝石、1.42 nm过渡矿物、蒙脱石和蛭石等,依次分别出现在100%、88.9%、72.2%、61.1%、44.4%和38.9%的剖面中。②黏粒矿物组成在纬度空间分布上具有明显规律性特征。随着纬度降低,土壤黏粒中的高岭石增加,伊利石、蒙脱石、1.42nm过渡矿物逐渐减少;纬度>23°N区域内,成土母质对黏粒矿物组成影响明显。③纬度23°N是黏粒矿物组成和土族矿物学类型分界线,<23°N区域,黏粒矿物均以高岭石为主,是"黏质"剖面的土族控制层段的主要矿物学类型;>23°N区域,黏粒矿物组成以高岭石、蒙脱石、伊利石或1.42 nm过渡矿物为主,因成土母质不同而异,"黏质"剖面的... 相似文献