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51.
Jeffrey L. Marion 《Environmental management》1995,19(5):763-771
A recreation impact monitoring system was developed and applied in 1984–1986 and in 1991 to all backcountry river-accessed
campsites within Delaware Water Gap National Recreation Area, Pennsylvania and New Jersey. Results suggest that actions implemented
by park managers in response to problems identified by the initial survey were highly effective in reducing resource degradation
caused by camping. In particular, the elimination of some designated campsites and installation of anchored firegrates reduced
the total area of disturbance by 50%. Firegrate installation provided a focal point that increased the concentration of camping
activities, allowing peripheral areas to recover. As suggested by predictive models, additional resource degradation caused
by increased camping intensities is more than offset by improvements in the condition of areas where use is eliminated. The
capabilities and management utility of recreation impact monitoring programs, illustrated by the Delaware Water Gap monitoring
program, are also presented and discussed. 相似文献
52.
娱乐及餐饮业近年来发展迅速,开展这类项目的环境影响评价工作首先应确保其环保审批手续的前置性。环评单位应在项目筹划初期介入,工作中应以项目合理选址和提出具有可操作性的污染防治措施这两个侧重面开展工作,作出准确的评价结论,给出可行的污染防治措施及方案。只有这样,才能编制出较为完善的环境影响评价文件,才能达到预防或减轻不良环境影响的最终目的。 相似文献
53.
Choosing Indicators of Natural Resource Condition: A Case Study in Arches National Park, Utah, USA 总被引:2,自引:0,他引:2
Jayne Belnap 《Environmental management》1998,22(4):635-642
/ Heavy visitor use in many areas of the world have necessitated development of ways to assess visitation impacts. Arches National Park recently completed a Visitor Experience and Resource Protection (VERP) plan. Integral to this plan was developing a method to identify biological indicators that would both measure visitor impacts and response to management actions. The process used in Arches for indicator selection is outlined here as a model applicableto many areas facing similar challenges. The steps were: (1) Vegetation types most used by visitors were identified. Impacted and unimpacted areas in these types were sampled, comparing vegetation and soil factors. (2) Variables found to differ significantly between compared sites were used as potential indicators. (3) Site-specific criteria for indicators were developed, and potential indicators evaluated using these criteria. (4) Chosen indicators were further researched for ecological relevancy. (5) Final indicators were chosen, field tested, and monitoring sites designated. In Arches, indicators were chosen for monitoring annually (soil crust index, soil compaction, number of used social trails and soil aggregate stability) and every five years (vegetation cover and frequency; ground cover; soil chemistry; and plant tissue chemistry).KEY WORDS: Biological indicators; Recreation impacts; Recreation management; Desert soils; Trampling 相似文献
54.
55.
Addressing onsite sampling in recreation site choice models 总被引:1,自引:0,他引:1
Independent experts and politicians have criticized statistical analyses of recreation behavior, which rely upon onsite samples due to their potential for biased inference. The use of onsite sampling usually reflects data or budgetary constraints, but can lead to two primary forms of bias in site choice models. First, the strategy entails sampling site choices rather than sampling individuals—a form of bias called endogenous stratification. Under these conditions, sample choices may not reflect the site choices of the true population. Second, exogenous attributes of the individuals sampled onsite may differ from the attributes of individuals in the population—the most common form in recreation demand is avidity bias. We propose addressing these biases by combining two the existing methods: Weighted Exogenous Stratification Maximum Likelihood estimation and propensity score estimation. We use the National Marine Fisheries Service's Marine Recreational Fishing Statistics Survey to illustrate methods of bias reduction, employing both simulated and empirical applications. We find that propensity score based weights can significantly reduce bias in estimation. Our results indicate that failure to account for these biases can overstate anglers' willingness to pay for improvements in fishing catch, but weighted models exhibit higher variance of parameter estimates and willingness to pay. 相似文献
56.
Gajanan Bhat John Bergstrom R. Jeff Teasley J. M. Bowker H. Ken Cordell 《Environmental management》1998,22(1):69-77
/ This paper describes a framework for estimating the economic value of outdoor recreation across different ecoregions. Ten ecoregions in the continental United States were defined based on similarly functioning ecosystem characters. The individual travel cost method was employed to estimate recreation demand functions for activities such as motor boating and waterskiing, developed and primitive camping, coldwater fishing, sightseeing and pleasure driving, and big game hunting for each ecoregion. While our ecoregional approach differs conceptually from previous work, our results appear consistent with the previous travel cost method valuation studies.KEY WORDS: Recreation; Ecoregion; Travel cost method; Truncated Poisson model 相似文献
57.
Gideon E. D. Omuta 《Journal of Environmental Planning and Management》1988,31(1):39-45
This paper attempts to provide an empirical basis for planning the optimisation of public outdoor recreational potential in Benin City, Nigeria. The study is seen as a partial analysis in that it considers only the deferred component of demand, and only with public recreational facilities. It identifies a mismatch between demand for and provision of facilities, due to an inadequate planning system. 相似文献
58.
Twenty Years of Change on Campsites in the Backcountry of Grand Canyon National Park 总被引:1,自引:1,他引:0
This article draws on three separate research and monitoring studies to describe 20-year trends in the number and condition
of campsites in the backcountry of Grand Canyon National Park. Results are used to assess the effectiveness of a complex and
innovative management program, adopted in 1983, that sought to concentrate use on designated campsites in popular places and
disperse camping in more remote places. In 1984, conditions on 12 high-use campsites and 12 low-use campsites were carefully
assessed. Conditions on 22 of these campsites were reassessed in 2005. In addition, campsite-monitoring surveys were conducted
between 1985 and 1992 and again in 2003 and 2004. In these surveys, all campsites were located and their condition rapidly
assessed. The detailed assessment of a sample of sites suggests relatively little change in condition during the 20-year period.
The high-use sites were more highly disturbed than the low-use sites, but they did not change more during the study period.
In contrast, changes at larger scales were dramatic. The total number of campsites more than doubled during the study period.
Surprisingly, the proliferation of new campsites was greater in places where camping was only allowed on designated campsites
than in places where camping was allowed anywhere. Concern that concentration of use on designated sites would cause unacceptable
impact was unfounded. Management implications for other internationally significant protected areas that allow backcountry
camping are explored. 相似文献
59.
This paper identifies factors that influence the demand for a bass fishing trip taken in the southeastern United States using a hurdle negative binomial count data model. The probability of fishing for a bass is estimated in the first stage and the fishing trip frequency is estimated in the second stage for individuals reporting bass fishing trips in the Southeast. The applied approach allows the decomposition of the effects of factors responsible for the decision to take a trip and the trip number. Calculated partial and total elasticities indicate a highly inelastic demand for the number of fishing trips as trip costs increase. However, the demand can be expected to increase if anglers experience a success measured by the number of caught fish or their size. Benefit estimates based on alternative estimation methods differ substantially, suggesting the need for testing each modeling approach applied in empirical studies. 相似文献
60.
/ The travel cost method was used to estimate the economic value of seven major power boating resources in Pennsylvania. A significant relationship between number of visitor trips and cost per visitor trip existed for five of the seven water bodies. The annual total value for those five resources was $396 million, which was 2.5 times greater than the total out-of-pocket expenditures of approximately $157 million visitors spent to visit them. Research results can help resource managers plan and craft programs and policies that are founded on economic values of the natural resources involved. 相似文献