全文获取类型
收费全文 | 6284篇 |
免费 | 44篇 |
国内免费 | 33篇 |
专业分类
安全科学 | 141篇 |
废物处理 | 278篇 |
环保管理 | 515篇 |
综合类 | 1013篇 |
基础理论 | 1552篇 |
环境理论 | 6篇 |
污染及防治 | 2000篇 |
评价与监测 | 466篇 |
社会与环境 | 370篇 |
灾害及防治 | 20篇 |
出版年
2024年 | 36篇 |
2023年 | 81篇 |
2022年 | 157篇 |
2021年 | 179篇 |
2020年 | 95篇 |
2019年 | 114篇 |
2018年 | 255篇 |
2017年 | 267篇 |
2016年 | 332篇 |
2015年 | 224篇 |
2014年 | 327篇 |
2013年 | 473篇 |
2012年 | 350篇 |
2011年 | 410篇 |
2010年 | 266篇 |
2009年 | 242篇 |
2008年 | 370篇 |
2007年 | 338篇 |
2006年 | 280篇 |
2005年 | 219篇 |
2004年 | 206篇 |
2003年 | 165篇 |
2002年 | 138篇 |
2001年 | 94篇 |
2000年 | 52篇 |
1999年 | 51篇 |
1998年 | 28篇 |
1997年 | 26篇 |
1996年 | 26篇 |
1995年 | 35篇 |
1994年 | 32篇 |
1993年 | 16篇 |
1992年 | 23篇 |
1991年 | 23篇 |
1990年 | 22篇 |
1989年 | 19篇 |
1988年 | 18篇 |
1987年 | 12篇 |
1986年 | 25篇 |
1985年 | 15篇 |
1984年 | 14篇 |
1983年 | 13篇 |
1982年 | 20篇 |
1980年 | 13篇 |
1976年 | 11篇 |
1966年 | 19篇 |
1965年 | 12篇 |
1964年 | 11篇 |
1956年 | 11篇 |
1954年 | 11篇 |
排序方式: 共有6361条查询结果,搜索用时 0 毫秒
81.
Miguel Delibes-Mateos Miguel ángel Farfán Jesús Olivero Ana Luz Márquez Juan Mario Vargas 《Environmental management》2009,43(6):1256-1268
Agricultural change has transformed large areas of traditional farming landscapes, leading to important changes in the species
community assemblages in most European countries. We suspect that the drastic changes in land-use that have occurred in Andalusia
(southern Spain) over recent decades, may have affected the distribution and abundance of game species in this region. This
article compares the distribution of the main game species in Andalusia during the 1960s and 1990s, using data from maps available
from the Mainland Spanish Fish, Game and National Parks Service and from recent datasets on hunting yield distributions, respectively.
Big-game and small-game species were significantly segregated in southern Spain during the 1990s, as two clearly independent
chorotypes (groups of species whose abundances are similarly distributed) were obtained from the classification analysis.
In contrast, big-game and small-game species were not significantly segregated several decades ago, when there was only one
chorotype consisting of small-game species and wild boar. The other three ungulates did not constitute a significant chorotype,
as they showed positive correlations with some species in the group mentioned above. These changes seem to be a consequence
of the transformations that have occurred in the Iberian Mediterranean landscape over the last few decades. The abandoning
of traditional activities, and the consequent formation of dense scrubland and woodland, has led to an expansion of big-game
species, and a decrease of small-game species in mountain areas. Moreover, agricultural intensification has apparently depleted
small-game species populations in some agricultural areas. On the other hand, the increasingly intensive hunting management
could be artificially boosting this segregation between small-game and big-game species. Our results suggest that the conservation
and regeneration of traditional agricultural landscapes (like those predominating in the 1960s) should be a priority for the
conservation of small-game species. 相似文献
82.
Global warming is negatively affecting the environment of the planet. This situation has led to the development of international standards, such as the International Organisation for Standardization's DIS 14064‐1 and the Greenhouse Gas Protocol Corporate Standard, both of which measure corporate carbon footprints. These standards provide guidelines that can be applied to different organizational sectors. However, these are not sufficient for controlling the reduction of carbon emissions, because although they propose the use of indicators, they do not explicitly define them. In addition, in the case of emissions from wastewater treatment, they only suggest that the emissions associated with this process be considered. In the present study, an eight‐step, unified methodology based on these two international standards is proposed, focusing on direct emissions. Moreover, the step‐by‐step to data collection, calculations, and the required indicators to control the emissions are defined. The first scope considers direct emissions from sources that are owned or controlled by the company. Methane generation measurement from wastewater treatment has been included in the methodology within Scope 1, as it is the second most polluting gas after carbon dioxide, both of which give rise to global warming. The proposed methodology was tested as a case study in one of the most important companies in the food sector in Colombia. 相似文献
83.
84.
85.
Myriam?MeradEmail author Nicolas?Dechy Frédéric?Marcel Igor?Linkov 《The Environmentalist》2013,33(2):305-321
Past and present disasters and scandals, such as the BP Deepwater Horizon oil disaster in the Gulf of Mexico in 2010, the Servier Mediator (Benfluorex) scandal in 2009 and the Enron collapse in 2001, have uncovered weaknesses in governance issues. The authors argue that there is a need to develop methods and tools to diagnose and assess the governance of organizations with respect to Sustainable Development (SD). However, this task remains difficult due to the fact that it is difficult to appraise the quality of governance. The authors propose a protocol to diagnose and analyze the governance of SD and explore the use of multiple-criteria decision-aiding methods to achieve this task. Two aggregation methods to assess the global governance are proposed: (1) The identification of a final governance index for an Organization. This method helps in establishing a global diagnosis of the quality of the governance of an Organization with respect to SD challenges. The governance index is based on the calculation of three indexes: the partial opportunity index, the partial risk index and the partial equilibrium index. (2) The ranking of a set of Organizations according to their governance of SD. This method aims at assessing a set of Organizations based on a pairwise comparison according to a set of criteria that represents the seven domains of the ISO 26000 norm (ISO 26000—Guidance on social responsibility, 2010). This method is based on the outranking aggregation approach ELECTRE III. A practical example is used to illustrate two methods of governance assessment. 相似文献
86.
Conan C Bouraoui F Turpin N de Marsily G Bidoglio G 《Journal of environmental quality》2003,32(6):2026-2032
In the intensive pig-farming (Sus scrofa) area of Brittany (western France), many surface and subsurface water resources are contaminated by nitrate (NO3) with concentrations that chronically exceed the European Community 50 mg L(-1) drinking standard. To ensure sustainable water supply, the fate of NO3 must be considered in both surface water and ground water. The fate of N was investigated in a Britain catchment, the Co?t-Dan watershed, with an integrated management tool: the hydrological SWAT model coupled with the ground water model MODFLOW, and its companion contaminant and solute transport model MT3DMS. The model was validated with respect to water quantity during a 6-yr period and for the NO3 concentration during a 44-mo period, at two gauging stations in the catchment. The coupled models reproduced accurately the measurements. At the basin outlet, the Nash-Sutcliffe coefficients were 0.88 for monthly flow for the entire period and 0.87 for monthly N load. Alternative scenarios were simulated and showed potential benefits of decreasing manure application from 210 to 170 kg N ha(-1) as required by the European Commission Nitrates Directive. 相似文献
87.
Ana Sofia Vaz Ricardo A. Moreno-Llorca João F. Gonçalves Joana R. Vicente Pablo F. Méndez Eloy Revilla Luis Santamaria Francisco J. Bonet-García João P. Honrado Domingo Alcaraz-Segura 《Conservation Letters》2020,13(3):e12704
In the “digital conservation” age, big data from Earth observations and from social media have been increasingly used to tackle conservation challenges. Here, we combined information from those two digital sources in a multimodel inference framework to identify, map, and predict the potential for nature's cultural contributions to people in two contrasting UNESCO biosphere reserves: Doñana and Sierra Nevada (Spain). The content analysis of Flickr pictures revealed different cultural contributions, according to the natural and cultural values of the two reserves. Those contributions relied upon landscape variables computed from Earth observation data: the variety of colors and vegetation functioning that characterize Doñana landscapes, and the leisure facilities, accessibility features, and heterogeneous landscapes that shape Sierra Nevada. Our findings suggest that social media and Earth observations can aid in the cost-efficient monitoring of nature's contributions to people, which underlie many Sustainable Development Goals and conservation targets in protected areas worldwide. 相似文献
88.
Ben Vanpeperstraete Sébastien Duyck Medani P. Bhandari Janis Brizga Leida Rijnhout Sylvia Lorek A. Peter Castro Chiung Ting Chang Herman Daly Robert J. Didham Gianluca Ferraro Oliver Greenfield Ashok Khosla Ernst Ulrich von Weizsäcker Birgit Lode Simon Miles Henrique Pacini Semida Silveira Leisa Perch Jaap Rijnsburger Mukul Sanwal Sameera Savarala S. Jacob Scherr Kallidaikurichi E. Seetharam A.M.M. Adeeb Donna Shepherd Adrian Smith Lisinka Ulatowska Alice Vincent Werner John 《Natural resources forum》2011,35(4):334-342
89.
Pasqualini V Oberti P Vigetta S Riffard O Panaïotis C Cannac M Ferrat L 《Environmental management》2011,48(1):38-56
Forest management can benefit from decision support tools, including GIS-based multicriteria decision-aiding approach. In
the Mediterranean region, Pinus pinaster forests play a very important role in biodiversity conservation and offer many socioeconomic benefits. However, the conservation
of this species is affected by the increase in forest fires and the expansion of Matsucoccus feytaudi. This paper proposes a methodology based on commonly available data for assessing the values and risks of P. pinaster forests and to generating maps to aid in decisions pertaining to fire and phytosanitary risk management. The criteria for
assessing the values (land cover type, legislative tools for biodiversity conservation, environmental tourist sites and access
routes, and timber yield) and the risks (fire and phytosanitation) of P. pinaster forests were obtained directly or by considering specific indicators, and they were subsequently aggregated by means of GIS-based
multicriteria analysis. This approach was tested on the island of Corsica (France), and maps to aid in decisions pertaining
to fire risk and phytosanitary risk (M. feytaudi) were obtained for P. pinaster forest management. Study results are used by the technical offices of the local administration—Corsican Agricultural and Rural Development Agency (ODARC)—for planning the conservation of P. pinaster forests with regard to fire prevention and safety and phytosanitary risks. The decision maker took part in the evaluation
criteria study (weight, normalization, and classification of the values). Most suitable locations are given to target the
public intervention. The methodology presented in this paper could be applied to other species and in other Mediterranean
regions. 相似文献
90.
We wanted to test the hypothesis that forest exposure to phytotoxic gases indirectly affects their carbon uptake. We estimated that the reduction of photosynthesis may have reached 20 to 30% at a site located 9 km (test site) from the Horne copper smelter in Rouyn-Noranda, which is a point source of SO2. Twenty-one spruce trees older than 100 yr were selected from seven sites at various distances from the smelter to evaluate conditions prior to and during the periods of smelter operation. The carbon isotope results obtained from spruce tree rings at our test site reveal an unprecedented and abrupt shift of +4/1000 after the onset of smelter operations. This large and permanent shift exceeds natural variations in regional pre-smelter series or in the series at a remote control site. All trees up to 116 km downwind from the smelter show delta13C positive shifts following the onset of operations. There is also a clear inverse relationship between the amplitude of the first-order trends and distance from the smelter. Those delta13C trends indicate that trees exposed to high levels of SO2 decrease their level of CO2 uptake through activation of stomatal closure. This is strongly supported by the significant departure of the Rouyn-Noranda trends from those measured for trees from non-industrialized areas of the Northern Hemisphere, or calculated using global atmospheric conditions. Considering the large number of SO2 point sources in North America, our results imply that CO2 uptake by the boreal forest in the vicinity of these sources may be lower than previously thought. 相似文献