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971.
生态工程治理玄武湖水污染效果的监测与评价 总被引:10,自引:1,他引:9
选取总磷、总氮、叶绿素a、浮游生物、浮游植物等多项环境监测指标,对利用生态工程治疗玄武湖水环境污染的效果进行了环境监测与评价。指出生态工程治理玄武湖水环境污染效果显著,经过治理使湖水中生物多样性大大增加,浮游植物大幅减少,湖水透明度增加,总磷、总氮等主要指标大幅下降,生态工程区中的水环境已从高度富营养化降到中度富营养化。 相似文献
972.
Parashar C Verma N Dixit S Shrivastava R 《Environmental monitoring and assessment》2008,140(1-3):119-122
Pollution of water bodies is one of the areas of major concern to environmentalists. Water quality is an index of health and
well being of a society. Industrialization, urbanization and modern agriculture practices have direct impact on the water
resources. These factors influence the water resources quantitatively and qualitatively. The study area selected were the
Upper lake and Kolar reservoir of Bhopal, the state capital of Madhya Pradesh, India. The Upper lake and Kolar reservoir both
are the important sources of potable water supply for the Bhopal city. The physico–chemical parameters like temperature, pH,
turbidity, total hardness, alkalinity, BOD, COD, Chloride, nitrate and phosphate were studied to ascertain the drinking water
quality. 相似文献
973.
Lah B Vidic T Glasencnik E Cepeljnik T Gorjanc G Marinsek-Logar R 《Environmental monitoring and assessment》2008,139(1-3):107-118
Combining genotoxicity/mutagenicity tests and physico-chemical methodologies can be useful for determining the potential genotoxic
contaminants in soil samples. The aim of our study was to evaluate the genotoxicity of soil by applying an integrated physico-chemical-biological
approach. Soil samples were collected at six sampling points in a Slovenian industrial and agricultural region where contamination
by heavy metals and sulphur dioxide (SO2) are primarily caused by a nearby power plant. The in vitro alkaline version of the comet assay on water soil leachates was
performed with Caco-2 and HepG2 cells. A parallel genotoxicity evaluation of the samples was performed by Ames test using
Salmonella typhimurium and the Tradescantia micronucleus test. Pedological analyses, heavy metal content determination, and different physico-chemical analyses, were
also performed utilizing standard methodology. Water leachates of soil samples were prepared according to standard methods.
Since only a battery of biotests with prokaryotic and eukaryotic organisms or cells can accurately estimate the effects of
(geno)toxicants in soil samples and water soil leachates, a combination of three bioassays, with cells or organisms belonging
to different trophic levels, was used. Genotoxicity of all six water soil leachates was proven by the comet assay on both
human cell lines, however no positive results were detected by bacterial assay, Ames test. The Tradescantia micronucleus assay showed increase in micronuclei formation for three samples. According to these results we can assume that
the comet assay was the most sensitive assay, followed by the micronucleus test. The Ames test does not appear to be sensitive
enough for water soil leachates genotoxicity evaluations where heavy metal contamination is anticipated. 相似文献
974.
The European Community asks its Member States to provide a comprehensive and coherent overview of their groundwater chemical
status. It is stated that simple conceptual models are necessary to allow assessments of the risks of failing to meet quality
objectives. In The Netherlands two monitoring networks (one for agriculture and one for nature) are operational, providing
results which can be used for an overview. Two regression models, based upon simple conceptual models, link measured nitrate
concentrations to data from remote sensing images of land use, national forest inventory, national cattle inventory, fertiliser
use statistics, atmospheric N deposition, soil maps and weather monitoring. The models are used to draw a nitrate leaching
map and to estimate the size of the area exceeding the EU limit value in the early 1990s. The 95% confidence interval for
the fraction nature and agricultural areas where the EU limit value for nitrate (50 mg/l) was exceeded amounted to 0.77–0.85
while the lower 97.5% confidence limit for the fraction agricultural area where the EU limit value was exceeded amounted to
0.94. Although the two conceptual models can be regarded as simple, the use of the models to give an overview was experienced
as complex. 相似文献
975.
Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in
this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting
from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into.
Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in
the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas
50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were
determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270
and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation,
coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses
yielded highly accurate results. There were positive correlations between some elements and their possible sources were the
same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek
was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought
to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m)
conservation areas should be determined in pollution areas along Karasu Creek and they should be improved. 相似文献
976.
Groundwater and water resources management play a key role in conserving the sustainable conditions in arid and semi-arid
regions. Applying some techniques that can reveal the critical and hot conditions of water resources seem necessary. In this
study, kriging and cokriging methods were evaluated for mapping the groundwater depth across a plain in which has experienced
different climatic conditions (dry, wet, and normal) and consequently high variations in groundwater depth in a 12 year led
in maximum, minimum, and mean depths. During this period groundwater depth has considerable fluctuations. Results obtained
from geostatistical analysis showed that groundwater depth varies spatially in different climatic conditions. Furthermore,
the calculated RMSE showed that cokriging approach was more accurate than kriging in mapping the groundwater depth though there was not a distinct
difference. As a whole, kriging underestimated the real groundwater depth for dry, wet, and normal conditions by 5.5, 2.2,
and 5.3%, while cokriging underestimations were 3.3, 2, and 2.2%, respectively; which showed the unbiasedness in estimations.
Results implied that in the study area farming and cultivation in dry conditions needs more attention due to higher variability
in groundwater depth in short distances compared to the other climate conditions. It is believed that geostatistical approaches
are reliable tools for water resources managers and water authorities to allocate groundwater resources in different environmental
conditions. 相似文献
977.
Altun L Baskent EZ Gunlu A Kadiogullari AI 《Environmental monitoring and assessment》2008,137(1-3):149-161
The productivity of forest sites has been indirectly determined with solo wood production objective in forest management.
Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest
management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method
and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed
and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements
were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study
area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications
were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes;
dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate
anamorphic site index (SI) equations and three site index classes; good (SI=I–II), medium (SI=III) and low (SI=IV–V) were
determined. Some important differences between the methods were realized. The forest sites determined with site index estimation
method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined
with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site
of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest
sites of open and degraded areas should be determined according to direct method. 相似文献
978.
979.
张家口市洋河、桑干河流域水环境健康风险评价 总被引:5,自引:1,他引:4
张家口市洋河、桑干河流域近几年来水质持续改善,为逐步恢复流域水质和下游官厅水库饮用水备用水源功能提供了条件.文章利用水环境健康风险评价模型,选取了2006年该流域水质监测数据,对流域内10个监测断面由饮水途径引起的水环境健康风险进行了评价.结果表明,该流域水体对人体健康危害最大的是化学致癌物Cr(VI),在各个监测断面中Cr(VI)的个人年风险均超过ICRP推荐的标准.同时,化学致癌物对人体健康危害的个人年风险超过非致癌物的个人年风险;因此对该流域水体的含化学致癌物Cr(VI)和As废水进行控制和治理是降低水环境健康风险的有效途径. 相似文献
980.
六道沟小流域主要灌木林地土壤干化研究 总被引:2,自引:0,他引:2
本文通过野外定位试验研究了黄土高原水蚀风蚀交错带典型区域陕西神木县六道沟小流域沙柳、柠条林地土壤水分状况。该区域主要灌木林地土壤水分亏缺严重。在沙柳林地,天然降水的补给深度约为0—100cm土层.土壤干层范围为0—480cm,在柠条林地,天然降水的补给深度约为0—200cm土层,土壤干层超过600cm,土壤质地、坡位等也影响灌木林地土壤干化层分布。 相似文献