全文获取类型
收费全文 | 5846篇 |
免费 | 356篇 |
国内免费 | 708篇 |
专业分类
安全科学 | 443篇 |
废物处理 | 33篇 |
环保管理 | 1076篇 |
综合类 | 2913篇 |
基础理论 | 580篇 |
环境理论 | 4篇 |
污染及防治 | 197篇 |
评价与监测 | 336篇 |
社会与环境 | 1084篇 |
灾害及防治 | 244篇 |
出版年
2024年 | 39篇 |
2023年 | 84篇 |
2022年 | 161篇 |
2021年 | 158篇 |
2020年 | 164篇 |
2019年 | 141篇 |
2018年 | 124篇 |
2017年 | 216篇 |
2016年 | 261篇 |
2015年 | 263篇 |
2014年 | 202篇 |
2013年 | 274篇 |
2012年 | 412篇 |
2011年 | 431篇 |
2010年 | 287篇 |
2009年 | 285篇 |
2008年 | 313篇 |
2007年 | 421篇 |
2006年 | 389篇 |
2005年 | 354篇 |
2004年 | 287篇 |
2003年 | 279篇 |
2002年 | 216篇 |
2001年 | 165篇 |
2000年 | 156篇 |
1999年 | 132篇 |
1998年 | 90篇 |
1997年 | 85篇 |
1996年 | 95篇 |
1995年 | 63篇 |
1994年 | 68篇 |
1993年 | 50篇 |
1992年 | 48篇 |
1991年 | 34篇 |
1990年 | 35篇 |
1989年 | 14篇 |
1988年 | 20篇 |
1987年 | 14篇 |
1986年 | 16篇 |
1985年 | 12篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 9篇 |
1981年 | 4篇 |
1980年 | 6篇 |
1979年 | 9篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1974年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有6910条查询结果,搜索用时 31 毫秒
691.
我国中西部生态脆弱带坡耕地水土流失及坡地梯化 总被引:2,自引:0,他引:2
中西部生态脆弱带是我国坡耕地集中分布地区 ,坡耕地水土流失是中西部生态脆弱带水土流失的主要类型 ,坡地梯化是防治坡耕地水土流失和实现坡耕地可持续利用的重要措施 ,国家应加大投资力度开展以坡地梯化为中心的坡耕地综合开发整治工作 相似文献
692.
2000年安徽省土地利用结构优化研究 总被引:5,自引:0,他引:5
本文分析了安徽省土地利用的现状与问题,揭示了各业用地之间的内在关联;并采用定性与定量相结合的方法,提出了2000年该省土地利用结构优化调整的方案和合理利用土地资源的对策。 相似文献
693.
P.C.F. Crowson 《Resources Policy》1982,8(1):3-12
The author reviews recent estimates of world resources and reserves and notes that reserves tend to grow with mineral consumption. Legal and economic constraints to the extraction of minerals are at least as important as physical availability. The author also points out that there is far more investment in minerals (government induced investment, companies diversifying into mining, etc) than some commentators suggest. However, the large mining projects of the 1960s belong to the past, and supplies of minerals may well become tight if there is a concerted economic boom. 相似文献
694.
In recent years, churches across the world have become involved in dialogue on the theory and practice of sustainable development. A number of Western churches have expressed their concern about climate change and destructive living patterns, stressing the need for human beings to exercise the care for all creation based on a life of sharing and sacrifice. Some Orthodox churches, however, quite recently included the environmental issues in their agendas. While the Bases of Social Concept, a major doctrine of the Russian Orthodox Church adopted in 2000, for the first time emphasises the Churchs position in overcoming environmental crisis and presents a solid basis on which to build the future environmental strategy of the Church, the Ethiopian Orthodox Church has not yet drawn up a programme document that might serve as a framework for the Churchs current extensive activities in the field of biodiversity conservation and sustainable forestry practices. Hence, despite certain closeness of both institutions, there is the potential for strengthening their roles in promoting sustainable development, based on the Biblical concept that the Earth belongs to the Lord and humans are responsible stewards assigned the duty to work for creation and care for it. This paper seeks to demonstrate by means of comparable analysis between the two Churches, Orthodox in nature but different in rites and religious practices, that traditional, highly conservative faiths may serve as powerful instruments of spreading out the ideas of sustainable development as the basis of spiritual revival in the situation of the two concurrent and interrelated crises – spiritual and ecological.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
695.
Koningsveld EA 《Journal of Safety Research》2005,36(3):231-236
INTRODUCTION: There are many available models that help evaluate the effectiveness of safety and health measures, but many are complex and require input from many departments within an organization. There is a need to develop a more user-friendly model. METHOD: A participative model was developed that involves face-to-face interviewers with workers, maintenance department, purchasing department and health and safety experts. They were asked about costs, efforts, benefits, and effects of gauging the effects of prevention efforts. RESULTS: Cost effectiveness analyses are essential in all cases and can include whatever the end-user requires, whether it is a small or lasting improvement. Having management participate helps validate the data. CONCLUSIONS: Organizations who collaborate with someone with at least some skill in cost-benefit evaluations will find that they will be able to establish policies and procedures from the data. The end result is a calculation that is understood by all involved. 相似文献
696.
Bergström M 《Journal of Safety Research》2005,36(3):237-240
INTRODUCTION: Measuring the effect of safety and health on production is a difficult value to gauge. METHOD: This article introduces the Potential, which is an instrument for economic analysis that incorporates different changes in conditions. RESULTS: While there are a number of problems associated with methods to determine these calculations, this method is a good indicator of the effects of safety and health and produces more than 300 variables with much less input. IMPACT ON INDUSTRY: Organizations can use this method effectively to determine how safety and health measure can improve their bottom line. A positive business case is highlighted. 相似文献
697.
建设资源节约型农业的途径与模式 总被引:1,自引:1,他引:0
王勤学 《中国人口.资源与环境》1993,3(1):55-58
建设资源节约型农业的根本途径是提高农业生产力。其中主要的措施有:科学利用气候资源,充分发挥气候生产潜力;十分珍惜每寸土地,努力提高土地生产率;大力推行节水措施,扩大农田灌溉面积;科学合理施肥,持续提高单产;提高能源利用率,解决农村能源短缺;实现人畜分粮,缓解人地关系;促进农产品商品流通,提高农业经济效益等。立体农业是发展资源节约型农业的最佳模式,也是中国式的高效益资源节约型农业的重要模式之一。 相似文献
698.
向赤忠 《长江流域资源与环境》1993,2(3):253-260
根据径流场观测材料、调查资料及历史事实,论述了乌江流域(四川部分)的水土流失现状、特点、危害及导致水土流失的自然因素和人为因素。针对该流域水土流失特点和原因提出了防治对策。 相似文献
699.
700.
长三角和珠三角土壤中汞的化学形态、转化和吸附特性 总被引:8,自引:0,他引:8
为了解长江三角洲和珠江三角洲农业土壤中汞的积累可能产生的环境影响,选择10个代表性农业土壤样品,研究了土壤中汞的化学形态、积累过程中形态的转化及吸附-解吸行为.研究表明,当无外源汞加入时,长江三角洲和珠江三角洲农业土壤中,汞主要以稳定的残余态形式存在.但随着汞加入量的增加,土壤中可交换态汞显著增加,增加程度与土壤性质有关.土壤pH是影响土壤汞有效性最重要的因素,其对土壤汞的吸附、解吸、形态转化和存在形态均有很大影响.土壤酸化可促进土壤汞的释放,加剧对环境的危害,防治土壤酸化也可有效降低土壤中汞对环境的危害. 相似文献