全文获取类型
收费全文 | 2768篇 |
免费 | 17篇 |
国内免费 | 35篇 |
专业分类
安全科学 | 75篇 |
废物处理 | 146篇 |
环保管理 | 274篇 |
综合类 | 491篇 |
基础理论 | 557篇 |
环境理论 | 2篇 |
污染及防治 | 820篇 |
评价与监测 | 251篇 |
社会与环境 | 184篇 |
灾害及防治 | 20篇 |
出版年
2023年 | 34篇 |
2022年 | 88篇 |
2021年 | 112篇 |
2020年 | 56篇 |
2019年 | 43篇 |
2018年 | 101篇 |
2017年 | 101篇 |
2016年 | 126篇 |
2015年 | 77篇 |
2014年 | 121篇 |
2013年 | 176篇 |
2012年 | 128篇 |
2011年 | 167篇 |
2010年 | 120篇 |
2009年 | 111篇 |
2008年 | 121篇 |
2007年 | 113篇 |
2006年 | 76篇 |
2005年 | 115篇 |
2004年 | 155篇 |
2003年 | 151篇 |
2002年 | 97篇 |
2001年 | 74篇 |
2000年 | 33篇 |
1999年 | 33篇 |
1998年 | 15篇 |
1997年 | 26篇 |
1996年 | 16篇 |
1995年 | 22篇 |
1994年 | 17篇 |
1993年 | 8篇 |
1992年 | 11篇 |
1991年 | 16篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1988年 | 5篇 |
1987年 | 10篇 |
1986年 | 8篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1979年 | 8篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1970年 | 4篇 |
1966年 | 3篇 |
1964年 | 4篇 |
1961年 | 3篇 |
排序方式: 共有2820条查询结果,搜索用时 16 毫秒
691.
Alejandro Jim��nez Fern��ndez de Palencia Agust�� P��rez-Foguet 《Sustainability Science》2011,6(1):37-49
This paper examines the challenge of achieving a balance between the implementation of centrally designed pro-poor policies
and the decentralization of responsibilities to local governments in many African countries. It analyzes the implementation
of the Rural Water Supply and Sanitation Program in Tanzania. Key mechanisms for planning and allocating resources are analyzed
at ministry, district, and village levels. Results show that a mixture of policy incoherencies, technical shortcomings and
political influence determine that only a small proportion of funds reaches the underserved areas. We argue that a greater
connection between the bottom-up and top-down planning mechanisms, and a sharp increase of downwards accountability are needed
before decentralized decision-making result in better resources allocation. Meanwhile a bigger intervention from central government
is needed. 相似文献
692.
693.
Freshwater protected areas are rare even though freshwater ecosystems are among the most imperiled in the world. Conservation actions within terrestrial protected areas (TPAs) such as development or resource extraction regulations may spill over to benefit freshwater ecosystems within their boundaries. Using data from 175 lakes across Ontario, Canada, we compared common indicators of fish‐assemblage status (i.e., species richness, Shannon diversity index, catch per unit effort, and normalized‐length size spectrum slopes) to evaluate whether TPAs benefit lake fish assemblages. Nearest neighbor cluster analysis was used to generate pairs of lakes: inside versus outside, inside versus bordering, and bordering versus outside TPAs based on lake characteristics. The diversity and abundance indicators did not differ significantly across comparisons, but normalized‐length size spectrum slopes (NLSS) were significantly steeper in lakes outside parks. The latter indicated assemblage differences (greater abundances of small‐bodied species) and less‐efficient energy transfer through the trophic levels of assemblages outside parks. Although not significantly different, pollution‐ and turbidity‐tolerant species were more abundant outside parks, whereas 3 of the 4 pollution‐intolerant species were more abundant within parks. Twenty‐one percent of the difference in slopes was related to higher total dissolved solids concentrations and angling pressure. Our results support the hypothesis that TPAs benefit lake fish assemblages and suggest that NLSS slopes are informative indicators for aquatic protected area evaluations because they represent compositional and functional aspects of communities. 相似文献
694.
Jean-Luc de Kok Guy Engelen Roger White Herman G. Wind 《Environmental Modeling and Assessment》2001,6(2):123-132
RaMCo is a prototype version of a decision-support system for coastal-zone management. The model is based on the findings of a multidisiciplinary research program, conducted in Southwest Sulawesi, Indonesia. Different management strategies can be compared on the basis of the short- and long-term consequences. Land-use change has been included in RaMCo in view of the impacts of land-based human activities on the marine environment. The key aspect of the model is a combination of the temporal dynamics of land-use change on the regional (macro-level) scale and spatial dynamics on the local (micro-level) scale. Constrained cellular automata are used to integrate both scale levels. The state changes of the cells depend on the consistency with the macro-scale model, local geographical conditions, and interaction with neighboring cells. In this paper, we discuss the underlying theoretical assumptions of the macro-scale and micro-scale models, some characteristic results for land-use change in the study area, and the validation problem. 相似文献
695.
Thaissa Sobreiro Carlos Edwar de Carvalho Freitas Karen Lorena Prado Fabíola Aquino do Nascimento Rafaela Vicentini Aprígio Mota Moraes 《Environment, Development and Sustainability》2010,12(6):1013-1024
We evaluated the implementation of a fishing agreement, which was created by negotiation among all users of the resources
as a co-management strategy because its definition was a result of meetings between all users of the resources. The fishing
agreement was implemented in Unini River, a tributary of the right bank of Negro River. Our approach was based on the perception
of the people who live in that area, called ribeirinhos. The management strategy was based on spatial distribution of the
different types of fishing. We used two logistic regression models to identify the variables which are important to determine
the previous concordance and satisfaction with the agreement. First, we analyzed the initial effort to implement the agreement.
The variable that influenced the decision of support for the agreement and satisfaction with the results of agreement in both
models was the distance from the interviewee’s residence to the sport fishing area. The results showed that the perception
of improvement in well-being of the communities and structured social organization are crucial for the success of the co-management
strategy. 相似文献
696.
Noel de Nevers J. Roger Morris 《Journal of the Air & Waste Management Association (1995)》2013,63(9):943-947
The rollback or proportional model is widely used in pollution control calculations and included in the guidelines for preparing and evaluating state implementation plans. Its basis and limitations are not widely known or understood. In this paper, the basis and limitations of rollback are listed and discussed, and extensions of basic rollback are proposed. 相似文献
697.
698.
Chantal Deden Kornelia Neveling Dimitra Zafeiropopoulou Christian Gilissen Rolph Pfundt Tuula Rinne Nicole de Leeuw Brigitte Faas Thatjana Gardeitchik Suzanne C. E. H. Sallevelt Aimee Paulussen Servi J. C. Stevens Esther Sikkel Mariet W. Elting Merel C. van Maarle Karin E. M. Diderich Nicole Corsten-Janssen Klaske D. Lichtenbelt Guus Lachmeijer Lisenka E. L. M. Vissers Helger G. Yntema Marcel Nelen Ilse Feenstra Wendy A. G. van Zelst-Stams 《黑龙江环境通报》2020,40(8):972-983
Objective
The purpose of this study was to explore the diagnostic yield and clinical utility of trio-based rapid whole exome sequencing (rWES) in pregnancies of fetuses with a wide range of congenital anomalies detected by ultrasound imaging.Methods
In this observational study, we analyzed the first 54 cases referred to our laboratory for prenatal rWES to support clinical decision making, after the sonographic detection of fetal congenital anomalies. The most common identified congenital anomalies were skeletal dysplasia (n = 20), multiple major fetal congenital anomalies (n = 17) and intracerebral structural anomalies (n = 7).Results
A conclusive diagnosis was identified in 18 of the 54 cases (33%). Pathogenic variants were detected most often in fetuses with skeletal dysplasia (n = 11) followed by fetuses with multiple major fetal congenital anomalies (n = 4) and intracerebral structural anomalies (n = 3). A survey, completed by the physicians for 37 of 54 cases, indicated that the rWES results impacted clinical decision making in 68% of cases.Conclusions
These results suggest that rWES improves prenatal diagnosis of fetuses with congenital anomalies, and has an important impact on prenatal and peripartum parental and clinical decision making. 相似文献699.
J. C. M. Pires A. Souza H. G. Pavão F. G. Martins 《Environmental science and pollution research international》2014,21(17):10550-10559
The effect of meteorological variables on surface ozone (O3) concentrations was analysed based on temporal variation of linear correlation and artificial neural network (ANN) models defined by genetic algorithms (GAs). ANN models were also used to predict the daily average concentration of this air pollutant in Campo Grande, Brazil. Three methodologies were applied using GAs, two of them considering threshold models. In these models, the variables selected to define different regimes were daily average O3 concentration, relative humidity and solar radiation. The threshold model that considers two O3 regimes was the one that correctly describes the effect of important meteorological variables in O3 behaviour, presenting also a good predictive performance. Solar radiation, relative humidity and rainfall were considered significant for both O3 regimes; however, wind speed (dispersion effect) was only significant for high concentrations. According to this model, high O3 concentrations corresponded to high solar radiation, low relative humidity and wind speed. This model showed to be a powerful tool to interpret the O3 behaviour, being useful to define policy strategies for human health protection regarding air pollution. 相似文献
700.
Andrei Nicoară Aurora Neagoe Paula Stancu Giovanni de Giudici Francesca Langella Anna Rosa Sprocati Virgil Iordache Erika Kothe 《Environmental science and pollution research international》2014,21(11):6905-6920
We performed an experiment at pot scale to assess the effect of plant growth-promoting bacteria (PGPB) on the development of five plant species grown on a tailing dam substrate. None of the species even germinated on inoculated unamended tailing material, prompting use of compost amendment. The effect of inoculation on the amended material was to increase soil respiration, and promote elements immobilisation at plant root surface. This was associated with a decrease in the concentrations of elements in the leaching water and an increase of plant biomass, statistically significant in the case of two species: Agrostis capillaris and Festuca rubra. The experiment was repeated at lysimeter scale with the species showing the best development at pot scale, A. capillaris, and the significant total biomass increase as a result of inoculation was confirmed. The patterns of element distribution in plants also changed (the concentrations of metals in the roots of A. capillaris and F. rubra significantly decreased in inoculated treatments, while phosphorus concentration significantly increased in roots of A. capillaris in inoculated treatment at lysimeter scale). Measured variables for plant oxidative stress did not change after inoculations. There were differences of A. capillaris plant–soil system response between experimental scales as a result of different substrate column structure and plant age at the sampling moment. Soil respiration was significantly larger at lysimeter scale than at pot scale. Leachate concentrations of As, Mn and Ni had significantly larger concentrations at lysimeter scale than at pot scale, while Zn concentrations were significantly smaller. Concentrations of several metals were significantly smaller in A. capillaris at lysimeter scale than at pot scale. From an applied perspective, a system A. capillaris—compost—PGPB selected from the rhizosphere of the tailing dam native plants can be an option for the phytostabilisation of tailing dams. Results should be confirmed by investigation at field plot scale. 相似文献