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841.
Structural physical habitat attributes include indices of stream size, channel gradient, substrate size, habitat complexity, and riparian vegetation cover and structure. The Environmental Monitoring and Assessment Program (EMAP) is designed to assess the status and trends of ecological resources at different scales. High-resolution remote sensing provides unique capabilities in detecting a variety of features and indicators of environmental health and condition. LIDAR is an airborne scanning laser system that provides data on topography, channel dimensions (width, depth), slope, channel complexity (residual pools, volume, morphometric complexity, hydraulic roughness), riparian vegetation (height and density), dimensions of riparian zone, anthropogenic alterations and disturbances, and channel and riparian interaction. Hyperspectral aerial imagery offers the advantage of high spectral and spatial resolution allowing for the detection and identification of riparian vegetation and natural and anthropogenic features at a resolution not possible with satellite imagery. When combined, or fused, these technologies comprise a powerful geospatial data set for assessing and monitoring lentic and lotic environmental characteristics and condition.  相似文献   
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The probability an individual is a carrier for a recessive disorder despite a negative carrier test, referred to as residual risk, has been part of carrier screening for over 2 decades. Residual risks are calculated by subtracting the frequency of carriers of pathogenic variants detected by the test from the carrier frequency in a population, estimated from the incidence of the disease. Estimates of the incidence (and therefore carrier frequency) of many recessive disorders differ among different population groups and are inaccurate or unavailable for many genes on large carrier screening panels for most of the world's populations. The pathogenic variants detected by the test and their frequencies also vary across groups and over time as variants are newly discovered or reclassified, which requires today's residual carrier risks to be continually updated. Even when a residual carrier risk is derived using accurate data obtained in a particular group, it may not apply to many individuals in that group because of misattributed ancestry or unsuspected admixture. Missing or inaccurate data, the challenge of determining meaningful ancestry-specific risks and applying them appropriately, and a lack of evidence they impact management, suggest that patients be counseled that although carrier screening may miss a small fraction of carriers, residual risks with contemporary carrier screening are well below the risk posed by invasive prenatal diagnosis, even if one member of the couple is a carrier, and that efforts to provide precise residual carrier risks are unnecessary.  相似文献   
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According to the targets set for sustainability, integrating the principles of sustainable development into country policies and programs is one of the main goals for development projects. A major challenge in the development field is cross-sectoral integrated planning and achieving multi-stakeholder consensus for collaborative joint projects, especially when sustainability is a goal. This increases the complexity of the multi-stakeholder interaction in decision making and requires enhanced mechanisms for stakeholder participation, coordination, and commitment beyond narrow self-interest. A critical aspect in the decision making process is to enable stakeholders to not only interpret and make decisions based on expert judgments, but also to appropriately involve the relevant parties in the research and decision making process. Therefore, scientific analyses in multi-stakeholder contexts have to be more transparent, participatory, and stakeholder-based in order to provide useful information to assist responsible decision making.This paper presents an outline of a stakeholder-based life cycle assessment approach that can be used to support sustainable decision making in multi-stakeholder contexts. The framework is discussed and compared to other common methods used to support environmental decision making in development projects. We argue that the fundamental concept of life cycle thinking can be effectively used to incorporate stakeholders in the research and decision making process, which can lead to more comprehensive, yet achievable assessments in collaboration with stakeholders. Life cycle thinking is not just a way to examine environmental impacts of activities, but also a way to comprehend and visualize a broader set of upstream and downstream consequences of decisions in development planning and implementation. A life cycle framework including the mapping of stakeholder involvement at each activity in upstream and downstream stages would give stakeholders a holistic view that they otherwise may not have.  相似文献   
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To offset the detrimental effects of urbanization on groundwater recharge, stormwater managers are focusing on infiltrating much of the runoff from a site that was generated because of development. For this to be effective, tools are required to predict the potential for contamination resulting from this infiltration for many site conditions, because infiltration should be stressed in areas where the least potential for causing groundwater contamination exists. Factors that influence contamination potential include the pollutant concentration in the runoff directed to the infiltration device and the ability of the underlying soil to remove the pollutant. The groundwater contamination potential of some pollutants, even those with high concentrations and moderate-to-high mobilities, can be reduced with proper pretreatment before infiltration. This paper presents a methodology that can be used to evaluate infiltration as an management option and introduces two different levels of models that could be used to evaluate contamination potential.  相似文献   
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Increasing the share of renewable energy is of principal concern for the EU energy policy. A number of policies have been adopted, and, in part, been implemented by the EU member countries. An increasing share of renewable energy implies an increasing utilisation of biofuels in general and of forest-based biomass in particular. However, in the EU, the endowment and uses of forest-base biomass are diverse suggesting that an increasing trade would become necessary in order to cost effectively increase the utilisation of forest-based biomass. The purpose of this study is to, in the presence of EU energy policy, quantify and analyse possible trade levels for forest fuels in the EU. Particularly, the consequences on trade after implementing the White Paper and the RES-E Directive are analysed. Investigating the European trade in forest fuels is important for understanding how industry sectors in the EU will be affected by the policies. The results suggest that the implementation of the White Paper and the RES-E Directive will increase the trade in forest fuels, resulting in total trade increases of up to 67 percent. Furthermore, the national net trading levels are possible to derive. Depending on policy implementation the results differ – a country that was net importing given the White Paper implementation can instead be net exporting when applying the RES-E Directive. The fact that the policy implementations will increase the trade may mitigate potential industry problems to secure the needed inputs. On the other hand, the integration of countries increases the possibility for some industries to increase their production even more, possibly strengthening any input scarcity problems. It is therefore not possible to generally conclude if a more integrated European forest fuel market, and hence an increased European forest fuel trade, will mitigate industry problems to secure their needed inputs or not.  相似文献   
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