全文获取类型
收费全文 | 424篇 |
免费 | 5篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 16篇 |
环保管理 | 47篇 |
综合类 | 79篇 |
基础理论 | 115篇 |
污染及防治 | 122篇 |
评价与监测 | 22篇 |
社会与环境 | 20篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 5篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 14篇 |
2017年 | 13篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 17篇 |
2013年 | 33篇 |
2012年 | 27篇 |
2011年 | 34篇 |
2010年 | 12篇 |
2009年 | 25篇 |
2008年 | 30篇 |
2007年 | 17篇 |
2006年 | 21篇 |
2005年 | 13篇 |
2004年 | 17篇 |
2003年 | 20篇 |
2002年 | 10篇 |
2001年 | 11篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有432条查询结果,搜索用时 390 毫秒
241.
Anne Mottet Benjamin Henderson Carolyn Opio Alessandra Falcucci Giuseppe Tempio Silvia Silvestri Sabrina Chesterman Pierre J. Gerber 《Regional Environmental Change》2017,17(1):129-141
Livestock can contribute to climate change mitigation by reducing their greenhouse gas emissions and by increasing soil carbon sequestration. Packages of mitigation techniques can bring large environmental benefits as illustrated in six case studies modeled in the Global Livestock Environmental Assessment Model developed by FAO. With feasible technical interventions in livestock production systems, the mitigation potential of each of the selected species, systems and regions ranges from 14 to 41 %. While comparably high mitigation potentials were estimated for ruminant and pig production systems in Asia, Latin America and Africa, large emission reductions can also be attained in dairy systems with already high levels of productivity, in OECD countries. Mitigation interventions can lead to a concomitant reduction in emissions and increase in production, contributing to food security. This is particularly the case for improved feeding practices and better health and herd management practices. Livestock systems also have a significant potential for sequestrating carbon in pasturelands and rangelands through improved management, as illustrated in two of the six case studies in this paper. 相似文献
242.
Battle?Karimi Pierre?Alain?Maron Nicolas?Chemidlin-Prevost Boure Nadine?Bernard Daniel?Gilbert Lionel?RanjardEmail author 《Environmental Chemistry Letters》2017,15(2):265-281
Evaluating the quality of ecosystems in terms of biological patrimony and functioning is of critical importance in the actual context of intensified human activities. Microbial diversity is commonly used as a bioindicator of ecosystems functioning. However, there is a lack of sensitivity of microbial diversity indicators in the case of moderate and chronic environmental degradation, such as atmospheric deposition of pollutants, agricultural practices, diffuse pollution by wastewater and climate change. As a consequence, there is a need for alternative bioindicators of soils and water quality. Here, we discuss the interest of adopting a more integrative approach based on biotic interaction networks beyond the simple diversity indicators. We review how the various biotic interactions can be integrated in the various microbial networks such as trophic, mutualistic and co-occurrence networks. Then we discuss the efficiency of microbial networks and associated metrics to detect changes in microbial communities. We conclude that the connectance, the number of links and the average degree of co-occurrence networks could vary from 10 to 50% in response to minor perturbations when microbial diversity parameters remain stable. Finally, we analyze studies that aimed at linking microbial networks and activity to evaluate the potential of such networks for providing simple and operational indicators of ecosystem quality and functioning. 相似文献
243.
There is a considerable interest in quantifying near-surface ozone concentrations and associated trends, as they serve to define the impacts on ozone of the anthropogenic precursors reductions and to evaluate the effects of emission control strategies. A statistical test has been used to the ozone air concentrations measured in the French rural monitoring network stations, called MERA, in order to bring out spatio-temporal trends in air quality in France over the 1995-2003 period. The non-parametric Mann-Kendall test has been developed for detecting and estimating monotonic trends in the time series and applied in our study at annual values: mean, 98th percentile and median based on hourly averaged ozone concentrations and applied to daily maxima. In France, when averaged overall 9 stations between 1995 and 2003, a slight increasing trend of the O(3) levels (+0.6 +/- 1.3% year( - 1)) is observed, which is strongly influenced by the concentrations of the high altitude stations. In stations below 1000 m a mean rate of -0.48% year( - 1) from annual average concentrations, of -0.45% year( - 1) for medians and of +0.56% year( - 1) for P.98 over the 1995-2003 period were obtained. In stations above 1,000 m a mean rate of +1.75% year( - 1) from annual averages values, of +4.05% year( - 1) for medians and of +2.55% year( - 1) for P.98 were calculated over the 1997-2003 period. This situation is comparable to the one observed in other countries. In Europe and in France a reduction of precursor emissions is observed whereas a slight increasing trend of the O(3) levels is observed over the 1995-2003 period. One reason is the non-linearity of chemical ozone production with respect to precursor emissions. Possible explanations are an increase in near-surface ozone values caused by a reduced ozone titration by reduced NO( x ), the meteorological parameters change, an increase in bio-geogenic compound concentrations, the intercontinental transport from North America and Asia and the influence of stratospheric-tropospheric exchanges. These possible explanations must be interpreted carefully as on the short time scales considered. 相似文献
244.
245.
Alexandra Baeta Ivan Valiela Francesca Rossi Rute Pinto Pierre Richard Nathalie Niquil João C. Marques 《Marine Biology》2009,156(10):2107-2120
In estuaries, eelgrass meadows contribute to fundamental ecosystem functions of estuaries, providing food to several predators
and buffering the negative effects of eutrophication. We asked whether the presence of the eelgrass Zostera noltii decreased the nitrogen concentration in the overlying water, affected the sources of nitrogen sequestrated by primary producers
and changed the benthic and pelagic food web structures. We also studied the importance of these food webs in providing food
to fish. We compared bare sediment to sediment covered by a Z. noltii meadow, and examined nutrient concentrations in the water column and δ15N in primary producers as indicators of anthropogenic inputs of nutrients. We then measured both δ13C and δ15N in the tissues of plants and consumers to establish food web structures. There were no differences in the concentrations
and sources of nitrogen between sites. Rather, δ15N values indicated anthropogenic inputs of N (e.g. sewage discharges, agriculture) in both sites. There were no major differences
in the structure of the planktonic food web, which was in part sustained by particulate organic matter and supported most
predator fish, and in the structure of the benthic food web. Nonetheless, there were differences in the sources of food for
omnivore consumers and for the detritivore Scrobicularia plana. Overall, the benthic food web did not use food derived from the eelgrass or macroalgae deposited on the substratum. Suspension
feeders used particulate and sediment organic matter, whereas the δ13C and δ15N values of the other consumers indicated a likely contribution of benthic microalgae. Furthermore, in both habitats we found
large variability in the isotope signatures of benthic macrofauna consumers, which did not allow distinguishing clearly different
trophic groups and indicated a high level of omnivory and a mixed diet opportunistically making use of the availability of
food in the surroundings. 相似文献
246.
247.
Habitat Matrix Effects on Pond Occupancy in Newts 总被引:9,自引:0,他引:9
Pierre Joly ‡ Claude Miaud § Anthony Lehmann † and Odile Grolet 《Conservation biology》2001,15(1):239-248
Abstract: In farmlands, the population viability of many amphibians is suspected to depend on the resistance the matrix of crop fields presents to movements between ponds and terrestrial sites and movements among ponds. Over recent decades the increase in cereal growing at the expense of cattle breeding has caused a drastic change in habitat matrix in many European regions. We investigated the effect of such change on populations of three newt species ( Triturus helveticus , T. alpestris , and T. cristatus ) by comparing their abundances in sites that varied in amount of cultivated ground. A multivariate regression analysis of the relationship of newt abundance to both pond and landscape variables demonstrated the negative influence of cultivated ground on abundance. The width of the uncultivated sector linking the pond to the forest was a good predictor of abundance after the influences of both pond area and fish presence were removed. Moreover, newt presence was positively related to the number of ponds within that 50-ha surrounding area, highlighting the role of metapopulation functioning in newt occupancy of ponds. The relationship between newt abundance and width of uncultivated sectors agrees with present knowledge of the orientation mechanisms that underlie migration movements in urodeles. Such a relationship between connectedness and sector width shows that narrow, linear corridors such as hedgerows may not be useful in newt conservation. Our study also highlights the need to incorporate a behavioral component of habitat use into models of connectivity in conservation biology. 相似文献
248.
Benn TM Westerhoff P Herckes P 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1334-1342
Detection methods are necessary to quantify fullerenes in commercial applications to provide potential exposure levels for future risk assessments of fullerene technologies. The fullerene concentrations of five cosmetic products were evaluated using liquid chromatography with mass spectrometry to separate and specifically detect C60 and C70 from interfering cosmetic substances (e.g., castor oil). A cosmetic formulation was characterized with transmission electron microscopy, which confirmed that polyvinylpyrrolidone encapsulated C60. Liquid-liquid extraction of fullerenes from control samples approached 100% while solid-phase and sonication in toluene extractions yielded recoveries of 27-42%. C60 was detected in four commercial cosmetics ranging from 0.04 to 1.1 μg/g, and C70 was qualitatively detected in two samples. A single-use quantity of cosmetic (0.5 g) may contain up to 0.6 μg of C60, demonstrating a pathway for human exposure. Steady-state modeling of fullerene adsorption to biosolids is used to discuss potential environmental releases from wastewater treatment systems. 相似文献
249.
Thierry Bellet Batrice Bailly-Asuni Pierre Mayenobe Aurlie Banet 《Safety Science》2009,47(9):1205-1221
This article provides a synthetic overview of the research programme carried out at INRETS-LESCOT over the last 10 years, in view to studying and modelling the mental representations of car drivers. Theoretically, this research is in line with two complementary scientific traditions: Human Information Processing theories on the one hand, and theories of Operative Activity on the other. As discussed in Section 1 of the article, attention is given to the functional representations of drivers, constructed “by” and “for” the action, such as they are implemented in a driving situation, and taking into account both implicit and explicit dimensions. This aim directly impacts on the methodological approach implemented, in so far as it entails defining an “experimental continuum” ranging from naturalistic observations of the driving activity (on the open road), to setting up more controlled experimental protocols in order to permit in-depth, systematic and reproducible scientific investigations of drivers’ cognition. Section 2 of the article presents a synthetic view of these methods, while Section 3 presents several significant results obtained with them. Lastly, the final part of the article focuses on the computational formalism defined at INRETS-LESCOT (i.e. the driving schemas) designed to model driver knowledge and mental representations, and developed in a COgnitive Simulation MOdel of the DRIVEr called COSMODRIVE. 相似文献
250.