全文获取类型
收费全文 | 10342篇 |
免费 | 866篇 |
国内免费 | 2711篇 |
专业分类
安全科学 | 586篇 |
废物处理 | 181篇 |
环保管理 | 1955篇 |
综合类 | 7267篇 |
基础理论 | 1247篇 |
环境理论 | 6篇 |
污染及防治 | 967篇 |
评价与监测 | 1140篇 |
社会与环境 | 455篇 |
灾害及防治 | 115篇 |
出版年
2024年 | 69篇 |
2023年 | 275篇 |
2022年 | 402篇 |
2021年 | 456篇 |
2020年 | 475篇 |
2019年 | 405篇 |
2018年 | 337篇 |
2017年 | 430篇 |
2016年 | 454篇 |
2015年 | 526篇 |
2014年 | 543篇 |
2013年 | 728篇 |
2012年 | 704篇 |
2011年 | 776篇 |
2010年 | 606篇 |
2009年 | 615篇 |
2008年 | 506篇 |
2007年 | 715篇 |
2006年 | 690篇 |
2005年 | 524篇 |
2004年 | 464篇 |
2003年 | 502篇 |
2002年 | 423篇 |
2001年 | 396篇 |
2000年 | 377篇 |
1999年 | 278篇 |
1998年 | 207篇 |
1997年 | 175篇 |
1996年 | 159篇 |
1995年 | 118篇 |
1994年 | 112篇 |
1993年 | 79篇 |
1992年 | 76篇 |
1991年 | 60篇 |
1990年 | 42篇 |
1989年 | 19篇 |
1988年 | 14篇 |
1987年 | 29篇 |
1986年 | 15篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1982年 | 15篇 |
1981年 | 17篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1978年 | 16篇 |
1977年 | 5篇 |
1973年 | 8篇 |
1972年 | 9篇 |
1971年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
971.
Progress in the research on aquatic environmental nonpoint source pollution in China 总被引:1,自引:0,他引:1
ProgresintheresearchonaquaticenvironmentalnonpointsourcepolutioninChinaBaoQuansheng,MaoXianqiang,WangHuadongInstituteofEnviro... 相似文献
972.
973.
通过对某尾矿库周边15个取样点的土壤进行取样调查,根据国家土壤环境质量标准(GB 15618—1995),采用单项污染指数法、综合污染指数法对该区的土壤重金属(Cu、Zn、Cd、Pb)含量进行评价。结果表明:所有采样点的土壤重金属含量均未超过GB 15618—1995二级标准值,各金属污染程度为Zn>Cu>Cd>Pb;采样点土壤中Cu含量均未超过GB 15618—1995一级标准值,Pb在采样点GW-3、GW-5、GW-6、GW-7的含量超过了GB 15618—1995一级标准值,Zn在采样点GW-2、GW-8的含量也超过了GB 15618—1995一级标准值,Cd在采样点GW-5、GW-7的含量超过GB15618—1995一级标准值;尾矿库四周污染程度依次为:东侧>南侧>北侧>西侧。 相似文献
974.
提出了利用水文和水质同步监测资料计算流域污染负荷空间分布的一般程序,并探讨了采用污染负荷贡献与集水区面积占比关系识别流域污染关键源区的方法,并在晋江流域进行了实例应用.结果表明:晋江下游取水口金鸡断面污染负荷主要来自东溪和西溪,枯水期CODMn、NH3-N和TP负荷分别是226.8、27.1和17.1g/s,占丰、平水期的18%~67%.丰、枯水期东溪和西溪对金鸡断面污染负荷贡献基本相当,而平水期西溪贡献显著大于东溪.晋江流域污染关键源区分别为蓬壶-长厅桥区间、长厅桥-港龙区间、横口-园美区间等5个断面区间,该关键源区识别方法不仅较好反映了污染物浓度和污染负荷在流域内的空间分布,同时还指出了主要污染物及敏感时期,可为后期的污染治理提供依据.本研究提出的污染负荷贡献计算程序以及关键源区识别方法具有较好的普适性,可为其他流域提供借鉴. 相似文献
975.
Z. Zlatev I. Dimov Tz. Ostromsky G. Geernaert I. Tzvetanov A. Bastrup-Birk 《Environmental Modeling and Assessment》2001,6(1):35-55
In order to help guide air pollution legislation at the European level, harmful air pollution effects on agriculture crops and the consequent economic implications for policy have been studied for more than a decade. Ozone has been labeled as the most serious of the damaging air pollutants to agriculture, where growth rates and consequently yields are dramatically reduced. Quantifying the effects has formed a key factor in policymaking. Based on the widely held view that AOT40 (Accumulated exposure Over Threshold of 40 ppb) is a good indicator of ozone-induced damage, the Danish Eulerian Model (DEM) was used to compute reduced agriculture yields on a 50 km×50 km grid over Europe. In one set of scenarios, a ten year meteorological time series was combined with realistic emission inventories. In another, various idealized emission reduction scenarios are applied to the same meteorological time series. The results show substantial inter-annual variability in economic losses, due in most part to meteorological conditions which varied much more substantially than the emissions during the same period. It is further shown that, taking all uncertainties into account, estimates of ozone-induced economic losses require that a long meteorological record is included in the analysis, for statistical significance to be improved to acceptable levels for use in policy analysis. In this study, calculations were made for Europe as a whole, though this paper presents results relevant for Denmark. 相似文献
976.
Hijano CF Domínguez MD Gimínez RG Sínchez PH García IS 《Environmental monitoring and assessment》2005,111(1-3):75-88
The evaluation of certain vascular plants that grow in the city of Madrid as biomonitors of SO2 air pollution in urban environments has been carried out. Total concentration of sulphur in leaves of the chosen higher plants
as well as other parameters in close relation to this contaminant (visible injury symptoms, chlorophyll a- and b-content and
peroxidase activity) have been determined in order to study the spatial distribution and temporal changes in SO2 deposition. Results obtained show that coniferous species such as Pinus pinea, were more sensitive to SO2 atmospheric concentration than leafy species as Quercux ilex subspecies ballota and, in the same way, bush species, such asPyracantha coccinea and Nerium oleander, were more sensitive than wooded species, such as Cedrus deodaraandPinus pinea, respectively. There is a higher accumulation of sulphur in vegetable species located near highways and dense traffic incidence
roads and near areas with high density of population. The minimum values for accumulation of SO2 were registered in winter and spring seasons (from January to April) due to the vegetative stop; while maximum values are
obtained during the summer season (from June to September), due to the stoma opening. The highest increments in sulphur concentration,
calculated as the difference between two consecutive months, are obtained in May and June for all considered species except
forCedrus deodara and Pyracantha coccinea, both species have few seasonal changes during the whole year. Some species are more sensitive to natural washing than others,
showing a decrease in sulphur concentration after rainfall periods. 相似文献
977.
“Measuring Sustainability”: A Multi-Criterion Framework 总被引:4,自引:0,他引:4
So far, the elementary question of whether one country’s or region’s economy is moving towards sustainability or away from it cannot be answered with unanimous consensus on the ‘measuring rod(s)’ to be employed. The main assumption of this article is that sustainability assessment needs a set of multi-dimensional indicators. From this assumption a question arises: how could such indicators be aggregated? Often, some indicators improve while others deteriorate. For instance, when incomes grow, SO2 might go down while CO2 increases. It has to be noted that this is the classical conflictual situation studied in multi-criteria decision theory. The use of a multi-criterion framework for making operational the ‘measuring of sustainability’ is discussed here by means of illustrative examples and more formal arguments. 相似文献
978.
J. M. Bewers 《Chemistry and Ecology》2013,29(1-2):9-23
Abstract Differences between the scientific and environmental policy communities regarding marine environmental protection strategies are discussed in the context of the nature and extent of scientific influence on marine environmental policy. Public perceptions of the nature and severity of marine pollution frequently differ from scientific assessments. the thesis of this paper is that the increasing influence of public perception on marine environmental protection policy is leading to the adoption of simplistic and unnecessarily extreme approaches to marine pollution prevention and to a reduced reliance on science. This trend is illustrated by some recent international developments and some suggestions are made towards enhancing the influence of science on marine protection policy. 相似文献
979.
Atmospheric air pollution turbulent fluxes can be assumed to be proportional to the mean concentration gradient. This assumption,
along with the equation of continuity, leads to the advection-diffusion equation. Moreover, large eddies are able to mix scalar
quantities in a manner that is counter to the local gradient. We present a general solution of a two-dimension steady state
advection-diffusion equation, considering non-local turbulence closure using the General Integral Laplace Transform Technique.
We show some examples of applications of the new solution with different vertical diffusion parameterisations. 相似文献
980.
巢湖流域不同土地利用类型地表径流污染特征研究 总被引:29,自引:2,他引:29
巢湖是我国五大淡水湖之一,目前正面临着严重的环境污染与水体富营养化问题。通过对巢湖流域塘西地区大豆地,水稻田,菜地,山芋地,小麦地,集镇街道,山坡地,饲养场地,农村道路,湖滩芦苇地,荒地等11种土地利用类型地表径流污染现状的详细调查与分析,建立了巢湖流域不同土地利用类型地表径流污染研究的一般程序与方法。 相似文献