首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   706篇
  免费   3篇
  国内免费   8篇
安全科学   19篇
废物处理   37篇
环保管理   78篇
综合类   127篇
基础理论   100篇
污染及防治   252篇
评价与监测   62篇
社会与环境   39篇
灾害及防治   3篇
  2023年   9篇
  2022年   22篇
  2021年   17篇
  2020年   13篇
  2019年   7篇
  2018年   19篇
  2017年   24篇
  2016年   30篇
  2015年   24篇
  2014年   44篇
  2013年   77篇
  2012年   51篇
  2011年   55篇
  2010年   30篇
  2009年   33篇
  2008年   53篇
  2007年   34篇
  2006年   35篇
  2005年   37篇
  2004年   20篇
  2003年   23篇
  2002年   13篇
  2001年   6篇
  2000年   3篇
  1999年   2篇
  1998年   4篇
  1997年   3篇
  1996年   4篇
  1995年   2篇
  1994年   6篇
  1993年   2篇
  1992年   2篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   3篇
  1986年   2篇
  1982年   1篇
  1978年   1篇
  1973年   1篇
  1954年   1篇
排序方式: 共有717条查询结果,搜索用时 469 毫秒
21.
Territorial user rights for fisheries have been advocated as a way to achieve sustainable resource management. However, few researchers have empirically assessed their potential as ancillary marine conservation instruments by comparing them to no‐take marine protected areas. In kelp (Lessonia trabeculata) forests of central Chile, we compared species richness, density, and biomass of macroinvertebrates and reef fishes among territorial‐user‐right areas with low‐level and high‐level enforcement, no‐take marine protected areas, and open‐access areas in 42 100‐m subtidal transects. We also assessed structural complexity of the kelp forest and substratum composition. Multivariate randomized permutation tests indicated macroinvertebrate and reef fish communities associated with the different access regimes differed significantly. Substratum composition and structural complexity of kelp forest did not differ among access regimes. Univariate analyses showed species richness, biomass, and density of macroinvertebrates and reef fishes were greater in highly enforced territorial‐user‐right areas and no‐take marine protected areas than in open‐access areas. Densities of macroinvertebrates and reef fishes of economic importance were not significantly different between highly enforced territorial‐user‐right and no‐take marine protected areas. Densities of economically important macroinvertebrates in areas with low‐level enforcement were significantly lower than those in areas with high‐level enforcement and no‐take marine protected areas but were significantly higher than in areas with open access. Territorial‐user‐right areas could be important ancillary conservation instruments if they are well enforced. Derechos de Usuario Territoriales para Pesquerías como Instrumentos Accesorios para la Conservación Marina Costera en Chile  相似文献   
22.
23.
24.
Environmental Science and Pollution Research - Construction and demolition waste (CDW) and municipal solid waste (MSW) are the waste flows mostly generated at a global level. In developing...  相似文献   
25.
This is a case study of contamination by a non-aqueous phase liquid (NAPL) that leaked from a chemical plant. The remediation procedure adopted for the initial phase of the plume migration was a plastic diaphragm wall coupled with a series of water extraction wells designed to avoid environmental impact on the surrounding ecosystems. Monitoring has shown that the containment is successful, and additional measures that contribute to accelerating remediation have been adopted. The authors wished to investigate how remediation might be further enhanced. The use of in situ aeration coupled with a system of soil vapor extraction (AS/SVE) has been chosen, since the remediation of sites with characteristics similar to those in this study, if based exclusively on dissolved-phase control, would take several decades to be completed. The transport of contaminant plumes has been simulated by using an analytical model to evaluate the effectiveness of the natural attenuation of the contaminant. The results of the simulation have confirmed the limited effectiveness of the natural attenuation of the contaminant, as well as the effective increase of remediation that would occur if the AS/SVE system is applied. A sensitivity analysis that included several combinations of increments of parameters that correspond to the decay rate of the source and the dissolved plume has simulated what might happen if the AS/SVE system is implemented.  相似文献   
26.
Several multicriteria evaluation techniques have been developed since the 1970s. The need to compare different territorial policies has justified their introduction into environmental research. These methods are based on the numerical manipulation of heterogeneous information, which varies in terms of reference scale and type of measure (continuous, ordinal, qualitative, binary, etc.). During recent years, diverse investigations have focused on general conditions on Salina, the “green island” of the Aeolian archipelago. Such studies, within an interdisciplinary project, aimed to explore the possibility of implementing conservation strategies that are compatible with human needs, landscape preservation, and sustainable economic development. Three different evaluation techniques are applied, namely multicriteria weighted concordance and discordance analysis and a qualitative procedure. They are used to compare four alternative plans for the socioeconomic development of Salina Island. These plans lie between extreme alternatives: total protection of natural resources and maximizing economic development based on tourism. The plans are compared to each other on the basis of 14 criteria that reflect the socioenvironmental perception of Salina's inhabitants. The approach used in this research seems particularly fruitful because of its flexibility: it offers decision makers the chance to manage heterogeneous data and information that is not easily quantifiable. Such “soft” information helps to evaluate environmental conditions more precisely, and to make a less damaging choice among alternative development plans.  相似文献   
27.
28.
The reestablishment of autochthonous plant species is an essential strategy for recovering degraded areas under semiarid conditions. A field experiment was carried out to assess the short-term effect of two reafforestation methods involving mycorrhizal inoculation and compost addition on soil quality parameters and Rhamnus lycioides seedling growth. The nutrient content (NPK) and enzymatic activities (dehydrogenase, urease, protease-BAA, acid phosphatase and beta-glucosidase) increased and bulk density decreased in the rhizosphere soil with the organic amendment. Biomass C of rhizosphere soil increased by at least 240% with respect to the control soil after mycorrhizal inoculation and the combination of compost addition + mycorrhizal inoculation. Both mycorrhizal inoculation and composted organic residue addition increased R. lycioides seedling growth in the same proportion. In the short term, we conclude that the application of both reafforestation methods not only enhances the establishment of R. lycioides seedlings, but also improves soil quality.  相似文献   
29.
Allometry, or the biology of scaling, is the study of size and its consequences. It has become a useful tool for comparative physiology. There are several allometric equations that relate body size to many parameters, including ingestion rate, lifespan, inhalation rate, home range and more. While these equations were originally derived from empirical observations, there is a growing body of evidence that these relationships have their origins in the dynamics of energy transport mechanisms. As part of an ongoing effort by the Department of Energy in developing generic methods for evaluating radiation dose to biota, we have examined the utility of applying allometric techniques to predicting radionuclide tissue concentration across a large range of terrestrial and riparian species of animals. This particular study examined 23 radionuclides. Initial investigations suggest that the allometric approach can provide a useful tool to derive limiting values of uptake and elimination factors for animals.  相似文献   
30.
/ Marginal aquatic systems (wetlands) of the Po River (Italy) have become the target of a renewed interest because of their value for recreation, natural reserves, and deposits of sand. To preserve these sites, wise management must be the objective of local administrations. In this paper a strategy for the sustainable use of 11 wetlands is presented. It uses simple economic analysis and multiple criteria techniques and provides suggestions to promote sustainability in terms of conservation of natural resources, economic self-sufficiency, and minimization of potential conflicts about the use of the wetlands. In the understanding that sustainability is framed in a long-term perspective, stability analysis is also considered and performed by means of loop analysis, a qualitative technique. Conditions for stability are then discussed about management opportunities.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号