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391.
392.
Lynn White Jr.’s “The Historical Roots of Our Ecologic Crisis,” which was published in Science in 1967, has played a critical role in precipitating interdisciplinary environmental studies. Although White advances a multifaceted argument, most respondents focus on his claim that the Judeo‐Christian tradition, especially Christianity, has promoted anthropocentric attitudes and environmentally destructive behaviors. Decades later, some scholars argue contrarily that Christianity in particular and the world's predominant religions in general are becoming more environmentally friendly, known as the greening‐of‐religion hypothesis. To test these claims, we conducted a comprehensive review of over 700 articles—historical, qualitative, and quantitative—that are pertinent to them. Although definitive conclusions are difficult, we identified many themes and dynamics that hinder environmental understanding and mobilization, including conservative theological orientations and beliefs about the role of divine agency in preventing or promoting natural events, whether the religion is an Abrahamic tradition or originated in Asia. On balance, we found the thrust of White's thesis is supported, whereas the greening‐of‐religion hypothesis is not. We also found that indigenous traditions often foster proenvironmental perceptions. This finding suggests that indigenous traditions may be more likely to be proenvironmental than other religious systems and that some nature‐based cosmologies and value systems function similarly. Although we conclude White's thesis and subsequent claims are largely born out, additional research is needed to better understand under what circumstances and communication strategies religious or other individuals and groups may be more effectively mobilized to respond to contemporary environmental challenges.  相似文献   
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394.
We formulate and simulation-test a spatial surplus production model that provides a basis with which to undertake multispecies, multi-area, stock assessment. Movement between areas is parameterized using a simple gravity model that includes a "residency" parameter that determines the degree of stock mixing among areas. The model is deliberately simple in order to (1) accommodate nontarget species that typically have fewer available data and (2) minimize computational demand to enable simulation evaluation of spatial management strategies. Using this model, we demonstrate that careful consideration of spatial catch and effort data can provide the basis for simple yet reliable spatial stock assessments. If simple spatial dynamics can be assumed, tagging data are not required to reliably estimate spatial distribution and movement. When applied to eight stocks of Atlantic tuna and billfish, the model tracks regional catch data relatively well by approximating local depletions and exchange among high-abundance areas. We use these results to investigate and discuss the implications of using spatially aggregated stock assessment for fisheries in which the distribution of both the population and fishing vary over time.  相似文献   
395.
A dynamic size-based model describing phosphorus (P) cycling in the epilimnion of lakes is established and validated against published data, and some influences of epilimnetic community structure and function on phosphorus cycling are investigated. We used literature values where possible and calibration otherwise to obtain parameter values. The simulation results show good agreement with empirical and experimental data. The model-derived turnover times of nanoplankton and mesoplankton exhibited a positive relationship with total phosphorus (TP), but the turnover times of larger size-functional groups did not. Nanoplankton and picoplankton became similar in their turnover times with increasing TP. Addition of fish altered the size of particulate P pools and turnover rates, decreased phosphate turnover times and decreased phosphorus sedimentation rates as expected from empirical studies. The model predictions appear to be robust and reasonably successful in reproducing the known behaviour of the P-cycle in the epilimnia of oligotrophic and mesotrophic lakes.  相似文献   
396.
This article addresses the narrowing interpretation of community when governmentalised: that of community's elision with local. First it surveys five broad academic and policy interpretations of the community implied in low carbon transitions. These demonstrate the persistence of community's broad and open-ended polysemy today. Second it looks more closely at the role community plays in UK environmental governance today, including specific evidence from two such government-funded community initiatives used to meet global environmental challenges: Transition Towns and Carbon Conversations. Third it provides a critique of community governance-beyond-the-state. It argues that community used to “jump scales” in response to global challenges like climate change, is often at its most narrow: local and governmentalised. Doing so helps contextualise the governmentalisation of (local-) community in UK environmental governance. Often it is localised in order to delegate (perceived) agency and responsibility onto individual actors at a local level.  相似文献   
397.
This collaborative study examined urbanization and impacts on area streams while using the best available sediment and erosion control (S&EC) practices in developing watersheds in Maryland, United States. During conversion of the agricultural and forested watersheds to urban land use, land surface topography was graded and vegetation was removed creating a high potential for sediment generation and release during storm events. The currently best available S&EC facilities were used during the development process to mitigate storm runoff water quality, quantity, and timing before entering area streams. Detailed Geographic Information System (GIS) maps were created to visualize changing land use and S&EC practices, five temporal collections of LiDAR (light detection and ranging) imagery were used to map the changing landscape topography, and streamflow, physical geomorphology, and habitat data were used to assess the ability of the S&EC facilities to protect receiving streams during development. Despite the use of the best available S&EC facilities, receiving streams experienced altered flow, geomorphology, and decreased biotic community health. These impacts on small streams during watershed development affect sediment and nutrient loads to larger downstream aquatic ecosystems such as the Chesapeake Bay.  相似文献   
398.
Although mediational designs and analyses are quite popular in Organizational Behavior research, there is much confusion surrounding the basis of causal inferences. We review theoretical, research design, and construct validity issues that are important for drawing inferences from mediational analyses. We then distinguish between indirect effects, and partial and full mediational hypotheses and outline decision points for drawing inferences of each type. An empirical illustration is provided using structural equation modeling (SEM) techniques, and we discuss extensions and directions for future research. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
399.
Sediments in the Port Jackson estuary are polluted by a wide range of toxicants and concentrations are among the highest reported for any major harbor in the world. Sediment quality guidelines (SQGs), developed by the National Oceanographic and Atmospheric Administration (NOAA) in the United States are used to estimate possible adverse biological effects of sedimentary contaminants in Port Jackson to benthic animals. The NOAA guidelines indicate that Pb, Zn, DDD, and DDE are the most likely contaminants to cause adverse biological effects in Port Jackson. On an individual chemical basis, the detrimental effects due to these toxicants may occur over extensive areas of the harbor, i.e., about 40%, 30%, 15% and 50%, respectively. The NOAA SQGs can also be used to estimate the probability of sediment toxicity for contaminant mixtures by determining the number of contaminants exceeding an upper guideline value (effects range medium, or ERM), which predicts probable adverse biological effects. The exceedence approach is used in the current study to estimate the probability of sediment toxicity and to prioritize the harbour in terms of possible adverse effects on sediment-dwelling animals. Approximately 1% of the harbor is mantled with sediment containing more than ten contaminants exceeding their respective ERM concentrations and, based on NOAA data, these sediments have an 80% probability of being toxic. Sediment with six to ten contaminants exceeding their respective ERM guidelines extend over approximately 4% of the harbor and have a 57% probability of toxicity. These areas are located in the landward reaches of embayments in the upper and central harbor in proximity to the most industrialised and urbanized part of the catchment. Sediment in a further 17% of the harbor has between one and five exceedences and has a 32% probability of being toxic. The application of SQGs developed by NOAA has not been tested outside North America, and the validity of using them in Port Jackson has yet to be demonstrated. The screening approach adopted here is to use SQGs to identify contaminants of concern and to determine areas of environmental risk. The practical application and management implications of the results of this investigation are discussed.  相似文献   
400.
As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves-highlighting the importance of this new and growing phenomenon. We analyze visitors' demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay 74.18 dollars per visit-day for nature-based recreation resulting in a total economic value of 484.56 million dollars attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida's unique ecosystems.  相似文献   
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