全文获取类型
收费全文 | 8097篇 |
免费 | 768篇 |
国内免费 | 3200篇 |
专业分类
安全科学 | 343篇 |
废物处理 | 129篇 |
环保管理 | 570篇 |
综合类 | 6741篇 |
基础理论 | 2790篇 |
污染及防治 | 634篇 |
评价与监测 | 614篇 |
社会与环境 | 188篇 |
灾害及防治 | 56篇 |
出版年
2024年 | 138篇 |
2023年 | 443篇 |
2022年 | 440篇 |
2021年 | 575篇 |
2020年 | 434篇 |
2019年 | 485篇 |
2018年 | 288篇 |
2017年 | 288篇 |
2016年 | 450篇 |
2015年 | 489篇 |
2014年 | 825篇 |
2013年 | 531篇 |
2012年 | 549篇 |
2011年 | 548篇 |
2010年 | 473篇 |
2009年 | 582篇 |
2008年 | 586篇 |
2007年 | 462篇 |
2006年 | 358篇 |
2005年 | 315篇 |
2004年 | 250篇 |
2003年 | 261篇 |
2002年 | 237篇 |
2001年 | 192篇 |
2000年 | 180篇 |
1999年 | 154篇 |
1998年 | 191篇 |
1997年 | 160篇 |
1996年 | 198篇 |
1995年 | 202篇 |
1994年 | 155篇 |
1993年 | 146篇 |
1992年 | 106篇 |
1991年 | 144篇 |
1990年 | 97篇 |
1989年 | 107篇 |
1988年 | 8篇 |
1987年 | 13篇 |
1986年 | 4篇 |
1979年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 578 毫秒
111.
112.
对有机食品生产基地的自然环境、土壤类型、植被覆盖率和水系的分布做了调查,对基地的土壤进行了布点监测和分析。 相似文献
114.
大气污染物浓度分布等值曲线的绘制是大气环境影响预测的一项重要工作.采用优化的黑白域矩形网格序列法,结合VB.NET环境下Metafile对象提供的矢量图形绘制新技术,可在一次数据扫描过程中同时实现黑白域划分、黑域边界提取、等值点拟合计算及序列化、等值线绘制等操作,计算量小、效率高、代码量少,可绘制任意浓度等值线,且等值线不相切. 相似文献
115.
Effects of acid deposition on forests in south China 总被引:1,自引:0,他引:1
1IntroductionWiththefastgrowingofmodernindustryandsharplyincreasingofenergyconsumptionprimarilycoal,airpolutionandaciddeposit... 相似文献
116.
117.
Determinationofpolychlorinatedbiphenylcongenersinenvironmentalsamples¥ChuShaogang;YangChun;XuXiaobai(ResearchCenterforEco-Env... 相似文献
118.
Wu Gang 《环境科学学报(英文版)》1996,8(4):499-503
LawsofannualnutrientuptakeinaPaulowniaplantation¥WuGang(ResearchCenterforEco-EnvironmentalSciences,ChineseAcademyofSciences,B... 相似文献
119.
This paper uses a prediction model of groundwater pollution based on the experiments in the laboratory and in field .The model, which was tested and calibrated by the field observated data ,satisfactorily simulated the field conditions in land treatment system of wastewater . Particularly , the model can provide the reliable pollution prediction of heavy metals , organisms and nitrogen . The model was used to predict the groundwater pollution caused by the land treatment system in the region of North China . The calibration of the model showed that correlation coefficients between the tested and predictive data of Cr6+. As3+, organism and NH4+ could reach 0.990, which proved that the model possessed the realistic instructive significance for design and use of wastewater land treatment systems . 相似文献
120.
The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau 总被引:3,自引:0,他引:3
Due to relatively strong human activities in the hilly area of Loess Plateau,the natural vegetation has been destroyed,and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land,grassland,woolland and orchard.This pattern has an important effect on soil moisture and soil nutrients.The Danangou catchment,a typical small catchment,was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper.The results are as follows:The comparisons of soil moisture among seven land uses for wet year and dry year were performed:(1)the average of soil moisture content for whole catchment was 12.11% in wet year,while it was 9.37% in dry year;(2)soil moisture among seven land uses was significantly different in dry year,but not in wet year;(3) form wet year to dry year,the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type;(4)the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope,while complicated distribution of soil moisture was observed in multiple land uses along slope.The relationships between soil nutrients and land uses and landscape positions were analysed:(1)five nutrient contents of soil organic matter(SOM),total N(TN),available N(AN),total P(TP) and available P(AP) in hilly area were lower than that in other areas.SOM content was less than 1%,TN content less than 0.07%,and TP fallow land and cropland,and higher level in soil fertility was found in crop-fruit intercropping land among croplands;(3)soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types. 相似文献