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941.
Safeguarding ecosystem services and biodiversity is critical to achieving sustainable development. To date, ecosystem services quantification has focused on the biophysical supply of services with less emphasis on human beneficiaries (i.e., demand). Only when both occur do ecosystems benefit people, but demand may shift ecosystem service priorities toward human-dominated landscapes that support less biodiversity. We quantified how accounting for demand affects the efficiency of conservation in capturing both human benefits and biodiversity by comparing conservation priorities identified with and without accounting for demand. We mapped supply and benefit for 3 ecosystem services (flood mitigation, crop pollination, and nature-based recreation) by adapting existing ecosystem service models to include and exclude factors representing human demand. We then identified conservation priorities for each with the conservation planning program Marxan. Particularly for flood mitigation and crop pollination, supply served as a poor proxy for benefit because demand changed the spatial distribution of ecosystem service provision. Including demand when jointly targeting biodiversity and ecosystem service increased the efficiency of conservation efforts targeting ecosystem services without reducing biodiversity outcomes. Our results highlight the importance of incorporating demand when quantifying ecosystem services for conservation planning.  相似文献   
942.
Recent research suggests that the occurrence of operational problems in advanced manufacturing technology (AMT) places stressful demands on operators. Applying Karasek's demand–control model, we predict that two properties of operational problems, namely technological uncertainty and abstractness, interact with timing and method control to predict operator strain. The results failed to confirm ordinal effects for timing or method control, but showed a dis-ordinal (crossover) interaction for timing control. While these findings provide little support for the demand–control model, they suggest that two new processes, namely ‘traction–distraction’ and ‘passivity–challenge’, are critical to understanding the nature of the relationship between operational problems and operator strain in AMT systems. We describe these processes and examine the implications for future research. © 1997 John Wiley & Sons, Ltd.  相似文献   
943.
944.
Urban woodlands: their role in reducing the effects of particulate pollution   总被引:41,自引:0,他引:41  
In recent years a substantial research effort has focused on the links between particulate air pollution and poor health. As a result the PM10 value has been set as a measure of such pollutants which can directly cause illness. Due to their large leaf areas relative to the ground on which they stand and the physical properties of their surfaces, trees can act as biological filters, removing large numbers of airborne particles and hence improving the quality of air in polluted environments. The role of vegetation and urban woodlands in reducing the effects of particulate pollution is reviewed here. The improvement of urban air quality achieved by establishing more trees in towns and cities is also illustrated.  相似文献   
945.
In response to the recent focus by the U.S. EnvironmentalProtection Agency on bioassessment of lakes, a multimetric index was developed for New Jersey lakes and reservoirs using benthicmacroinvertebrates. Benthic samples were collected fromreference and impaired lakes with muck and intermediate sedimentsin central and northern New Jersey during summer 1997. We used astepwise process to evaluate properties of candidate metrics andselected five for the Lake Macroinvertebrate Integrity Index(LMII): Hilsenhoff Biotic Index (HBI), percent chironomidindividuals, percent collector-gatherer taxa, percentoligochaetes/leeches, and number of Diptera taxa. We scoredmetrics as the fraction of the best expected value (based on allsites) achieved at a site and summed them into the LMII. Evaluation of the LMII showed that it discriminated well betweenreference and impaired lakes and was strongly related to severalpotential stressors. Chemical and physical gradients distinguished between reference and impaired lakes, and the LMIIsummarized these gradients well. The LMII corresponded stronglywith land use, but some lakes with more urban land use stillachieved high scores. Based on a power analysis, the ability ofthe LMII to detect differences in condition was sensitive to thenumber of samples from each lake.  相似文献   
946.
Little effort has been devoted to differentiating between hydrocarbon losses through evaporation and biodegradation in treatability studies of fuel-contaminated Antarctic soils. When natural attenuation is being considered as a treatment option, it is important to be able to identify the mechanism of hydrocarbon loss and demonstrate that rates of degradation are sufficient to prevent off-site migration. Similarly, where complex thermally enhanced bioremediation schemes involve nutrient addition, water management, air stripping and active heating, it is important to appreciate the relative roles of these mechanisms for cost minimisation. Following the loss of hydrocarbons by documenting changes in total petroleum hydrocarbons offers little insight into the relative contribution of evaporation and biodegradation. We present a methodology here that allows identification and quantification of evaporative losses of diesel range organics at a range of temperatures using successively less volatile compounds as fractionation markers. We also present data that supports the general utility of so-called biodegradation indices for tracking biodegradation progress. We are also able to show that at 4 degrees C indigenous Antarctic soil bacteria degrade Special Antarctic Blend fuel components in the following order: naphthalene and methyl-napthalenes, light n-alkanes, then progressively heavier n-alkanes; whereas isoprenoids and the unresolved complex mixture are relatively recalcitrant.  相似文献   
947.
There has been much recent interest in the concept of rewilding as a tool for nature conservation, but also confusion over the idea, which has limited its utility. We developed a unifying definition and 10 guiding principles for rewilding through a survey of 59 rewilding experts, a summary of key organizations’ rewilding visions, and workshops involving over 100 participants from around the world. The guiding principles convey that rewilding exits on a continuum of scale, connectivity, and level of human influence and aims to restore ecosystem structure and functions to achieve a self-sustaining autonomous nature. These principles clarify the concept of rewilding and improve its effectiveness as a tool to achieve global conservation targets, including those of the UN Decade on Ecosystem Restoration and post-2020 Global Biodiversity Framework. Finally, we suggest differences in rewilding perspectives lie largely in the extent to which it is seen as achievable and in specific interventions. An understanding of the context of rewilding projects is the key to success, and careful site-specific interpretations will help achieve the aims of rewilding.  相似文献   
948.
Reducing costs and increasing benefits for rural communities coexisting with large carnivores is necessary for conservation of jaguar (Panthera onca) and puma (Puma concolor). To design acceptable incentives, stakeholders must be involved in the process. We conducted an innovative, structured, group communication process based on a Delphi technique as a template for identifying potential incentives. Community workshops with 133 members of 7 communities and surveys with 25 multidisciplinary experts from government, nongovernmental organizations, and academia provided iterative data to design a plan of incentives through 4 rounds of discussion. The final product integrated 862 ideas into 6 types of incentives: organization of communities, mechanisms for improved dialogue, citizen technical assistance, green labeling for community products, payment for the ecosystem service of biodiversity, and an assessment of financial alternatives. We used quantitative and qualitative techniques to indicate support for decisions about the design of incentives, which reduced researcher subjectivity. The diverse incentives developed and the cooperation from multiple stakeholders resulted in an incentive plan that integrated issues of governance, equity, and social norms.  相似文献   
949.
950.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.  相似文献   
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