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91.
A supportive attitude of residents towards protected areas is crucial for successful implementation and management, particularly in densely populated regions such as Central Europe. While previous studies have revealed that emotional and cultural drivers, as well as information level and group membership, can influence attitudes towards protected areas, the effect of place-attachment dimensions remains unclear. A postal survey among local residents (N = 460) explored factors influencing attitudes towards the Lungau (-Nockberge) Biosphere Reserve in Austria before its official recognition. Results indicated societal support throughout all socio-demographic strata. A logistic regression showed that, besides socio-demographics and information level, place attachment had a significant influence on the acceptance of the biosphere reserve. Supporters and opponents showed both high place identity and dependence, while waverers scored low on these dimensions. Results indicate that place attachment is relevant for the design of participatory processes as well as for developing management policies for biosphere reserves.  相似文献   
92.
Urban ecosystems are often sources of nonpoint source (NPS) nitrogen (N) pollution to aquatic ecosystems. However, N export from urban watersheds is highly variable. Examples of densely urbanized watersheds are not well studied, and these may have comparatively low export rates. Commonly used metrics of landscape heterogeneity may obscure our ability to discern relationships among landscape characteristics that can explain these lower export rates. We expected that differences not often captured by these metrics in the relative cover of vegetation, structures, and impervious surfaces would better explain observed variation in N export. We examined these relationships during storms in residential watersheds. Contrary to expectations, land cover did not directly predict variation in N or water export. Instead, N export was strongly linked to drainage infrastructure density. Our research highlights the role of fine‐scaled landscape attributes, mainly infrastructure, in explaining patterns of N export from densely urbanized watersheds. Changes to hydrologic flow paths by infrastructure explained more variation in N export than land cover. Our findings support further development of landscape ecological models of urban N export that focus on hydrologic modification by infrastructure rather than traditional landscape measures such as land use, as indicators for evaluating patterns of NPS nitrogen pollution in densely urbanized watersheds.  相似文献   
93.
Regional municipal water plans typically do not recognize complex coupling patterns or that increased withdrawals in one location can result in changes in water availability in others. We investigated the interaction between urban growth and water availability in the Baltimore metropolitan region where urban growth has occurred beyond the reaches of municipal water systems into areas that rely on wells in low‐productivity Piedmont aquifers. We used the urban growth model SLEUTH and the hydrologic model ParFlow.CLM to evaluate this interaction with urban growth scenarios in 2007 and 2030. We found decreasing groundwater availability outside of the municipal water service area. Within the municipal service area we found zones of increasing storage resulting from increased urban growth, where reduced vegetation cover dominated the effect of urbanization on the hydrologic cycle. We also found areas of decreasing storage, where expanding impervious surfaces played a larger role. Although the magnitude of urban growth and change in water availability for the simulation period were generally small, there was considerable spatial heterogeneity of changes in subsurface storage. This suggests that there are locally concentrated areas of groundwater sensitivity to urban growth where water shortages could occur or where drying up of headwater streams would be more likely. The simulation approach presented here could be used to identify early warning indicators of future risk.  相似文献   
94.
Urban stormwater practices are individually diverse, but they are components of an overall urban watershed system. This study proposes a conceptual model of that system, including its component spatial areas, their arrangement along the flow route, and their associations with urban land uses and values. The model defines three spatial areas along the flow route which have evolved over time into their present forms: (1) the source area, which is arranged and furnished primarily or entirely for human use, accommodation, and comfort; (2) the perimeter area, where specialized stormwater facilities carry away source‐area runoff or buffer downstream areas from its impacts; and (3) the downstream area, which receives the discharges from the perimeter or directly from the source area. Each area presents a specific combination of stormwater features and human interactions, and excludes others. Considering stormwater flows and functions in the context of physical urban spaces brings into view the spaces’ urban structures and interacting agendas. This model allows practitioners to navigate conceptually through the system, and to focus appropriate objectives and structures on each project site.  相似文献   
95.
Understanding the connotation and principles of ecological compensation in water source reserve areas is the basis and guarantee for establishing and improving the ecological compensation mechanism of water source reserve areas. First, this paper reviews the three stages of ecological compensation research progress. Based on the review, using the theory of externality, the ecological environment system of water source reserve areas is then analyzed. This paper argues that the connotation of ecological compensation in water source reserve areas is a kind of institutional arrangement, which is designed to internalize externalities. Finally, based on the understanding of the connotation of ecological compensation in water source reserve areas, five principles for establishing and improving the ecological compensation mechanism are proposed, including the principle of fairness and justice, the principle of equivalence of equality and responsibility, the principle of flexibility and effectiveness, the principle of “earmark funds, and implementation by law,” and the principle of government compensation supplemented with market compensation.  相似文献   
96.
Despite biological invasions being a worldwide phenomenon causing significant ecological, economic, and human welfare impacts, there is limited understanding regarding how environmental managers perceive the problem and subsequently manage alien species. Spanish environmental managers were surveyed using questionnaires to (1) analyze the extent to which they perceive plant invasions as a problem; (2) identify the status, occurrence, and impacts of noxious alien plant species; (3) assess current effort and expenditure targeting alien plant management; and, finally, (4) identify the criteria they use to set priorities for management. In comparison to other environmental concerns, plant invasions are perceived as only moderately problematic and mechanical control is the most valued and frequently used strategy to cope with plant invasions in Spain. Based on 70 questionnaires received, 193 species are considered noxious, 109 of which have been the subject of management activities. More than 90% of species are found in at least one protected area. According to respondents, the most frequently managed species are the most widespread across administrative regions and the ones perceived as causing the highest impacts. The perception of impact seems to be independent of their invasion status, since only half of the species identified as noxious are believed to be invasive in Spain, while 43% of species thought to only be casual aliens are causing a high impact. Records of management costs are poor and the few data indicate that the total actual expenditure amounted to 50,492,437 € in the last decade. The majority of respondents stated that management measures are insufficient to control alien plants due to limited economic resources, lack of public awareness and support, and an absence of coordination among different public administrations. Managers also expressed their concern about the fact that much scientific research is concerned with the ecology of alien plants rather than with specific cost-efficient strategies to manage alien species.  相似文献   
97.
Background, aims, and scope  Since toxaphene (polychlorocamphene, polychloropinene, or strobane) mixtures were applied for massive insecticide use in the 1960s to replace the use of DDT, some of their congeners have been found at high latitudes far away from the usage areas. Especially polychlorinated bornanes have demonstrated dominating congeners transported by air up to the Arctic areas. Environmental fate modeling has been applied to monitor this phenomenon using parallel zones of atmosphere around the globe as interconnected environments. These zones, shown in many meteorological maps, however, may not be the best way to configure atmospheric transport in air trajectories. The latter could also be covered by connecting a chain of simple model boxes. We aim to study this alternative approach by modeling the trajectory chain using catchment boxes of our FATEMOD model. Polychlorobornanes analyzed in biota of the Barents Sea offered one case to study this modeling alternative, while toxaphene has been and partly still is used massively at southern East Europe and around rivers flowing to the Aral Sea. Materials and methods  Pure model substances of three polychlorobornanes (toxaphene congeners P26, P50, and P62) were synthesized, their environmentally important thermal properties measured by differential scanning calorimetry, as evaluated from literature data, and their temperature dependences estimated by the QSPR programs VPLEST, WATSOLU, and TDLKOW. The evaluated property parameters were used to model their atmospheric long-range transport from toxaphene heavy usage areas in Ukraine and Aral/SyrDarja/AmuDarja region areas, through East Europe and Northern Norway (Finnmarken) to the Barents Sea. The time period used for the emission model was June 1997. Usual weather conditions in June were applied in the model, which was constructed by chaining FATEMOD model boxes of the catchment’s areas along assumed maximal air flow trajectories. Analysis of the three chlorobornanes in toxaphene mixtures function as a basis for the estimates of emission levels caused by its usage. High estimate (A) was taken from contents in a Western product chlorocamphene and low estimate (B) from mean contents in Russian polychloroterpene products to achieve modeled water concentrations. Bioaccumulation to analyzed lipid of aquatic biota at the target region was estimated by using statistical calculation for persistent organic pollutants in literature. Results  The results from model runs A and B (high and low emission estimate) for levels in sea biota were compared to analysis results of samples taken in August 1997 at Barents Sea. The model results (ng g−1 lw): 4–95 in lipid of planktovores and 7–150 in lipid of piscivores, were in fair agreement with the analysis results from August 1997: 21–31 in Themisto libellula (chatka), 26–42 in Boreocadus saida (Polar cod), and 5–27 in Gadus morhua (cod) liver. Discussion  The modeling results indicate that the application of chained simple multimedia catchment boxes on predicted trajectory is a useful method for estimation of volatile airborne persistent chemical exposures to biota in remote areas. For hazard assessment of these pollutants, their properties, especially temperature dependences, must be estimated by a reasonable accuracy. That can be achieved by using measurements in laboratory with pure model compounds and estimation of properties by thermodynamic QSPR methods. The property parameters can be validated by comparing their values at an environmental temperature range with measured or QSPR-estimated values derived by independent methods. The chained box method used for long-range air transport modeling can be more suitable than global parallel zones modeling used earlier, provided that the main airflow trajectories and properties of transported pollutants are predictable enough. Conclusions  Long-range air transport modeling of persistent, especially photo-resistant organic compounds using a chain of joint simple boxes of catchment’s environments is a feasible method to predict concentrations of pollutants at the target area. This is justified from model results compared with analytical measurements in Barents Sea biota in August 1997: three of six modeled values were high and the other three low compared to the analysis results. The order of magnitude level was similar in both modeled (planktovore and piscivore) and observed (chatka and polar cod) values of lipid samples. The obtained results were too limited to firm validation but are sufficient to justify feasibility of the method, which prompts one to perform more studies on this modeling system. Recommendations and perspectives  For assessment of the risk of environmental damages, chemical fate determination is an essential tool for chemical control, e.g., for EU following the REACH rules. The present conclusion of applicability of the chained single-box multimedia modeling can be validated by further studies using analyses of emissions and target biota in various other cases. To achieve useful results, fate models built with databases having automatic steps for most calculations and outputs accessible to all chemical control professionals are essential. Our FATEMOD program catchments at environments and compound properties listed in the database represent a feasible tool for local, regional, and, according our present test results, for global exposure predictions. As an extended use of model, emission estimates can be achieved by reversed modeling from analysis results of samples corresponding to the target area. This article is dedicated to the memory of Professor Alexander B Terentiev (who passed away in November 2006), our true friend. With his Institute of Organo-Element Compounds, Russian Academy of Science, Moscow, he was an important main organizer of the six joint Finnish–Russian seminars (every third year since 1989) on the field (‘Chemistry and Ecology of Organo-Element Compounds’). He prompted us especially to search properties and environmental fates for various polyhalogen compounds. We remember him for his friendly character and great sense of humor.  相似文献   
98.
The results of studies on postfire succession in larch forests of the permafrost zone are discussed. The main directions of successional processes in burned-out areas of different ages are described. It has been shown that secondary pyrogenic successions in larch forests follow the scheme of rapid regeneration without tree species replacement and the model of succession tolerance. Groups of plant species with different life strategies and indicator species characterizing different stages of the overgrowing of burned-out areas have been identified.  相似文献   
99.
文章阐述了国内外海油陆采HSE管理现状,通过分析总结滩海油气生产设施从设计到投入使用全过程HSE管理经验,归纳整理出可借鉴的HSE管理技术,为中国石油海油陆采油田HSE文化的培育提供了有益的建议。  相似文献   
100.
航运企业航运安全评价研究   总被引:5,自引:2,他引:3  
在研讨现阶段航运安全评价技术进展的基础上,认为航运企业航运安全评价,宜采用定量和定性相结合的组合评价方法。因而构建了基于多级模糊综合评价方法的航运企业"航运安全"评价模型,从评价指标选取、指标体系建立、指标权重分析等入手,对航运企业的航运安全进行研究,并使用多级模糊综合评价方法对某航运企业A的航运安全进行了评价分析。通过分析,认为该企业急需加强企业航运安全文化建设,并加强航运企业管理体系和船员心理品质的培养。希望研究成果能为航运企业管理者提供一种全面认识和评价企业安全管理工作的工具和方法。  相似文献   
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