全文获取类型
收费全文 | 135篇 |
免费 | 1篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 1篇 |
环保管理 | 25篇 |
综合类 | 17篇 |
基础理论 | 39篇 |
污染及防治 | 33篇 |
评价与监测 | 8篇 |
社会与环境 | 10篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 14篇 |
2012年 | 7篇 |
2011年 | 13篇 |
2010年 | 4篇 |
2009年 | 6篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 8篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1985年 | 3篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有138条查询结果,搜索用时 140 毫秒
131.
132.
133.
Breininger DR Nichols JD Duncan BW Stolen ED Carter GM Hunt DK Drese JH 《Ecology》2010,91(11):3354-3364
Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance-prone ecosystems. We identify the correspondence between multistate capture-recapture models and Markov models of habitat dynamics. We exploit this correspondence by fitting and comparing competing models of different ecological covariates affecting habitat transition probabilities in Florida scrub and flatwoods, a habitat important to many unique plants and animals. We subdivided a large scrub and flatwoods ecosystem along central Florida's Atlantic coast into 10-ha grid cells, which approximated average territory size of the threatened Florida Scrub-Jay (Aphelocoma coerulescens), a management indicator species. We used 1.0-m resolution aerial imagery for 1994, 1999, and 2004 to classify grid cells into four habitat quality states that were directly related to Florida Scrub-Jay source-sink dynamics and management decision making. Results showed that static site features related to fire propagation (vegetation type, edges) and temporally varying disturbances (fires, mechanical cutting) best explained transition probabilities. Results indicated that much of the scrub and flatwoods ecosystem was resistant to moving from a degraded state to a desired state without mechanical cutting, an expensive restoration tool. We used habitat models parameterized with the estimated transition probabilities to investigate the consequences of alternative management scenarios on future habitat dynamics. We recommend this multistate modeling approach as being broadly applicable for studying ecosystem, land cover, or habitat dynamics. The approach provides maximum-likelihood estimates of transition parameters, including precision measures, and can be used to assess evidence among competing ecological models that describe system dynamics. 相似文献
134.
Howard BJ Beresford NA Nisbet A Cox G Oughton DH Hunt J Alvarez B Andersson KG Liland A Voigt G 《Journal of environmental radioactivity》2005,83(3):275-295
The STRATEGY project (Sustainable Restoration and Long-Term Management of Contaminated Rural, Urban and Industrial Ecosystems) aimed to provide a holistic decision framework for the selection of optimal restoration strategies for the long-term sustainable management of contaminated areas in Western Europe. A critical evaluation was carried out of countermeasures and waste disposal options, from which compendia of state-of-the-art restoration methods were compiled. A decision support system capable of optimising spatially varying restoration strategies, that considered the level of averted dose, costs (including those of waste disposal) and environmental side effects was developed. Appropriate methods of estimating indirect costs associated with side effects and of communicating with stakeholders were identified. The importance of stakeholder consultation at a local level and of ensuring that any response is site and scenario specific were emphasised. A value matrix approach was suggested as a method of addressing social and ethical issues within the decision-making process, and was designed to be compatible with both the countermeasure compendia and the decision support system. The applicability and usefulness of STRATEGY outputs for food production systems in the medium to long term is assessed. 相似文献
135.
Long-term (1975–1981) and short-term (1980–1981) national and regional trends in ozone (O3) are examined. The data used in this paper come from the U.S. Environmental Protection Agency's National Aerometric Data Bank (NADB). Air quality trends are presented for both the National Air Monitoring Sites (NAMS) and all other sites meeting the historical and data completeness criteria. Nationally, the composite average of the second-highest daily maximum 1-h O3 values recorded at 209 sites decreased 14% between 1975 and 1981. An even greater improvement was observed in the estimated number of exceedances in the ozone season (July–September), which decreased 42%. Volatile organic compound (VOC) emissions decreased 9% during the same time period. The greater improvement observed in ozone levels appears to be a combination of reductions in VOC emissions and the change in the calibration procedure which took place between 1978 and 1979. Between 1980 and 1981, the majority of the 159 monitoring sites with data in both years decreased with a median rate of improvement of 8%. This is consistent with the 7% drop in VOC emissions during this period. 相似文献
136.
137.
Kensuke Okada William R. Pitchers Manmohan D. Sharma John Hunt David J. Hosken 《Behavioral ecology and sociobiology》2011,65(9):1773-1778
Intraspecific variation in a resting metabolic rate (RMR) is likely to be an important determinant of energetic-resource use
and may influence the resources subsequently available for allocation to traits not directly associated with somatic maintenance.
The influence of RMR on resource availability could be especially important for condition-dependent sexual traits, such as
cricket calls, that are themselves energetically costly to produce. RMR may also be associated with longevity, either negatively
because individuals with a high RMR burn resources faster and die young, or positively as individuals with high RMR are more
able to accrue resources to fuel survival. Additionally, the associations between RMR and other characters may vary across
populations if differential selection or drift shapes these traits. Here we tested for differences in RMR, body mass, calling
effort, and longevity in two populations of cricket Gryllodes sigillatus and then evaluated the potential influence of RMR on calling and longevity. We find that RMR, calling effort, and longevity
varied across populations, but mass did not. Controlling for population and mass, RMR was not significantly associated with
calling effort, but was negatively associated with longevity. These findings suggest that male crickets that live fast die
young. 相似文献
138.