全文获取类型
收费全文 | 2131篇 |
免费 | 21篇 |
国内免费 | 17篇 |
专业分类
安全科学 | 42篇 |
废物处理 | 105篇 |
环保管理 | 175篇 |
综合类 | 285篇 |
基础理论 | 531篇 |
环境理论 | 2篇 |
污染及防治 | 701篇 |
评价与监测 | 173篇 |
社会与环境 | 149篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 23篇 |
2022年 | 75篇 |
2021年 | 71篇 |
2020年 | 37篇 |
2019年 | 39篇 |
2018年 | 129篇 |
2017年 | 108篇 |
2016年 | 142篇 |
2015年 | 69篇 |
2014年 | 119篇 |
2013年 | 163篇 |
2012年 | 136篇 |
2011年 | 171篇 |
2010年 | 99篇 |
2009年 | 92篇 |
2008年 | 123篇 |
2007年 | 119篇 |
2006年 | 91篇 |
2005年 | 70篇 |
2004年 | 67篇 |
2003年 | 33篇 |
2002年 | 30篇 |
2001年 | 26篇 |
2000年 | 14篇 |
1999年 | 15篇 |
1998年 | 5篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 7篇 |
1994年 | 6篇 |
1993年 | 9篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1966年 | 3篇 |
1965年 | 2篇 |
1964年 | 5篇 |
1961年 | 2篇 |
1960年 | 2篇 |
1959年 | 3篇 |
1955年 | 1篇 |
1954年 | 2篇 |
排序方式: 共有2169条查询结果,搜索用时 15 毫秒
101.
de Nazelle A Nieuwenhuijsen MJ Antó JM Brauer M Briggs D Braun-Fahrlander C Cavill N Cooper AR Desqueyroux H Fruin S Hoek G Panis LI Janssen N Jerrett M Joffe M Andersen ZJ van Kempen E Kingham S Kubesch N Leyden KM Marshall JD Matamala J Mellios G Mendez M Nassif H Ogilvie D Peiró R Pérez K Rabl A Ragettli M Rodríguez D Rojas D Ruiz P Sallis JF Terwoert J Toussaint JF Tuomisto J Zuurbier M Lebret E 《Environment international》2011,37(4):766-777
102.
Ecosystem services and hydroelectricity in Central America: modelling service flows with fuzzy logic and expert knowledge 总被引:1,自引:0,他引:1
Bruno Locatelli Pablo Imbach Raffaele Vignola Marc J. Metzger Efraín José Leguía Hidalgo 《Regional Environmental Change》2011,11(2):393-404
Because ecosystem services are generally not produced and used in the same place, their assessment should consider the flows
of services from ecosystems to users. These flows depend on the characteristics and spatial distribution of ecosystems and
users, the spatial relationships between them, and the presence of filters or barriers between ecosystems and users. The objective
of this paper is to map the ecosystem services provided to the Costa Rican and Nicaraguan hydroelectric sectors, which are
crucial sectors for national sustainable development and depend directly on hydrological ecosystem services. The paper presents
an approach for modelling the flows of multiple services from diverse ecosystems to diverse users through different kinds
of filters in a landscape. The approach uses expert knowledge and fuzzy numbers to handle uncertainties. The analyses for
Costa Rica and Nicaragua show how the approach helps identify priority areas for the conservation and restoration of forests
for the services they provide to the hydroelectric sector. As such, it is a useful tool for defining spatially targeted policies
for the conservation of ecosystem services and for involving the users of ecosystem services in ecosystem management. 相似文献
103.
Luís Costa Kirsten Thonicke Benjamin Poulter Franz-W. Badeck 《Regional Environmental Change》2011,11(3):543-551
Within the changing fire regimes of Portugal, the relative importance of humans and climatic variability for regional fire
statistics remains poorly understood. This work investigates the statistical relationship between temporal dynamics of fire
events in Portugal and a set of socioeconomic, landscape, and climatic variables for the time periods of 1980–1990, 1991–2000,
and extreme fires years. For 10 of 15 districts, it was possible to observe moderate shifts in the significance of fire drivers
for the first two decadal periods. For others, pronounced changes of the significance of fire drivers were found across time.
Results point toward a dynamic (perhaps highly non-linear) behavior of socioeconomic and landscape fire drivers, especially
during the occurrence of extreme fire years of 2003 and 2005. At country level, population density alone explained 42% of
the inter-annual and inter-district deviance in number of fires. At the same temporal and spatial scale, the explanatory power
of temperature anomalies proved to explain 43% of area burnt. We highlight the necessity of including a broad set of socioeconomic
and landscape fire drivers in order to account for potential significance shifts. In addition, although climate does trigger
broad favorable fire conditions across Portugal mainland, socioeconomic and landscape factors proved to determine much of
the complex fire patterns at a subnational scale. 相似文献
104.
Marc Gracia Nacima Meghelli Lluís Comas Javier Retana 《Regional Environmental Change》2011,11(2):349-358
The current state of Mediterranean mountain areas has been driven by two main factors: intense traditional human activity
and the dynamics of the ecosystem itself. In this study, we examine land-cover changes in a National Park in the Pyrenees
mountains (NE Iberian Peninsula), which was designated a protected area 55 years ago. First, we have analyzed spatio-temporal
changes in land-cover pattern and forest dynamics from 1957 to 2005. During this period, land-cover dynamics consisted of
two main processes: (i) expansion of the forest area and (ii) increasing cover of forests already present in 1957. To analyze
the role of the conservation level of the park, we have also compared the results obtained within the park with those of unprotected,
peripheral areas. In the two areas with different protection level, dense forests increased throughout the period because
of the reduction in forestry activities. The peripheral area showed a higher rate of forest-cover change from 1957 to 2005
compared to the National Park. This higher increase in forest cover in the peripheral area could be related to a higher proportion
in the National Park of screes and rocky areas and to the decline and transformation of forest activities in these peripheral,
lower elevation areas. 相似文献
105.
Rundqvist S Hedenås H Sandström A Emanuelsson U Eriksson H Jonasson C Callaghan TV 《Ambio》2011,40(6):683-692
Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic
Sweden. We recorded the change in coverage of shrub and tree species over a 32– to 34-year period, in three 50 × 50 m plots;
in the alpine-tree-line ecotone. The cover of shrubs and trees (<3.5 cm diameter at breast height) were estimated during 2009–2010
and compared with historical documentation from 1976 to 1977. Similarly, all tree stems (≥3.5 cm) were noted and positions
determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs
and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory. 相似文献
106.
This study was conducted in the Swedish sub-Arctic, near Abisko, in order to assess the direction and scale of possible vegetation
changes in the alpine–birch forest ecotone. We have re-surveyed shrub, tree and vegetation data at 549 plots grouped into
61 clusters. The plots were originally surveyed in 1997 and re-surveyed in 2010. Our study is unique for the area as we have
quantitatively estimated a 19% increase in tree biomass mainly within the existing birch forest. We also found significant
increases in the cover of two vegetation types—“birch forest-heath with mosses” and “meadow with low herbs”, while the cover
of snowbed vegetation decreased significantly. The vegetation changes might be caused by climate, herbivory and past human
impact but irrespective of the causes, the observed transition of the vegetation will have substantial effects on the mountain
ecosystems. 相似文献
107.
Ochoa-Hueso R Allen EB Branquinho C Cruz C Dias T Fenn ME Manrique E Pérez-Corona ME Sheppard LJ Stock WD 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2265-2279
We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. 相似文献
108.
Novais SC Gomes SI Gravato C Guilhermino L De Coen W Soares AM Amorim MJ 《Environmental pollution (Barking, Essex : 1987)》2011,159(7):1836-1843
To better understand chemical modes of action, emphasis has been given to stress responses at lower levels of biological organization. Cholinesterases and antioxidant defenses are among the most used biomarkers due to their crucial role in the neurocholinergic transmission and in cell homeostasis preventing DNA damage, enzymatic inactivation and lipid peroxidation. The main goal of this study was to investigate the effects of zinc and cadmium on survival and reproduction of E. albidus and to assess metals oxidative stress potential and neurotoxic effects at concentrations that affected reproduction. Both metals affected the enchytraeids’ survival and reproduction and induced significant changes in the antioxidant defenses as well as increased lipid peroxidation, indicating oxidative damage. This study demonstrates that determining effects at different levels of biological organization can give better information on the physiological responses of enchytraeids in metal contamination events and further unravel the mechanistic processes dealing with metal stress. 相似文献
109.
Real C Ángel Fernández J Aboal JR Carballeira A 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2797-2800
Multivariate analysis of environmental data sets requires the absence of missing values or their substitution by small values. However, if the data is transformed logarithmically prior to the analysis, this solution cannot be applied because the logarithm of a small value might become an outlier. Several methods for substituting the missing values can be found in the literature although none of them guarantees that no distortion of the structure of the data set is produced. We propose a method for the assessment of these distortions which can be used for deciding whether to retain or not the samples or variables containing missing values and for the investigation of the performance of different substitution techniques. The method analyzes the structure of the distances among samples using Mantel tests. We present an application of the method to PCDD/F data measured in samples of terrestrial moss as part of a biomonitoring study. 相似文献
110.
Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences 总被引:1,自引:0,他引:1
Silvia JerezMiguel Motas María José PalaciosFrancisco Valera José Javier Cuervo Andrés Barbosa 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2412-2419
Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adélie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 μg g−1 dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 μg g−1 dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine. 相似文献