全文获取类型
收费全文 | 789篇 |
免费 | 39篇 |
国内免费 | 10篇 |
专业分类
安全科学 | 48篇 |
废物处理 | 4篇 |
环保管理 | 321篇 |
综合类 | 174篇 |
基础理论 | 103篇 |
污染及防治 | 57篇 |
评价与监测 | 55篇 |
社会与环境 | 47篇 |
灾害及防治 | 29篇 |
出版年
2025年 | 3篇 |
2024年 | 13篇 |
2023年 | 14篇 |
2022年 | 12篇 |
2021年 | 18篇 |
2020年 | 21篇 |
2019年 | 15篇 |
2018年 | 17篇 |
2017年 | 23篇 |
2016年 | 28篇 |
2015年 | 15篇 |
2014年 | 26篇 |
2013年 | 37篇 |
2012年 | 30篇 |
2011年 | 42篇 |
2010年 | 24篇 |
2009年 | 52篇 |
2008年 | 55篇 |
2007年 | 65篇 |
2006年 | 29篇 |
2005年 | 22篇 |
2004年 | 23篇 |
2003年 | 17篇 |
2002年 | 19篇 |
2001年 | 17篇 |
2000年 | 19篇 |
1999年 | 16篇 |
1998年 | 16篇 |
1997年 | 9篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 2篇 |
1989年 | 9篇 |
1988年 | 3篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 5篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 8篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1973年 | 1篇 |
排序方式: 共有838条查询结果,搜索用时 0 毫秒
121.
Carbon footprint of food - approaches from national input-output statistics and a LCA of a food portion 总被引:1,自引:0,他引:1
Yrjö Virtanen Sirpa KurppaMerja Saarinen Juha-Matti KatajajuuriKirsi Usva Ilmo MäenpääJohanna Mäkelä Juha GrönroosAri Nissinen 《Journal of Cleaner Production》2011,19(16):1849-1856
The aim of the study, on which this paper is based, was to provide guidance to consumers to make environmentally responsible choices in their food consumption, to assist food supply chain stakeholders to identify the key areas for environmental improvements, and to provide policy makers with a tool for monitoring the potential impacts on climate change resulting from developments within the food sector. At the macro level, the EIO-LCA model was developed specifically for the Finnish food chain; at the micro level, LCAs were performed on 30 lunch portions. The contribution of the Finnish food chain to climate change was 14%, which comprised 40% CO2 emissions, 25% CH4 emissions, and 34% N2O emissions. The share of impacts from domestic agricultural processes was the highest, at 69%. The impact of a single lunch portion ranged between 0.65 and 3.80 kg of equivalent CO2. According to the EIO-LCA model, the average impact was 7.7 kg CO2 eq/person daily. The consumer phase accounted for between 8 and 47% of the climate change impacts for homemade portions. In ready-to-eat portions industry and retail phases were emphasized, representing 25-38% of climate change impacts. We present an approach to steer the Finnish food sector onto an environmentally sustainable path; practical tools for consumers and farmers will especially need to be developed further. 相似文献
122.
政策环境影响评价与公众参与——国家有毒化学品立法EIA中的公众参与 总被引:4,自引:1,他引:4
阐明在我国开展政策EIA的必要性,从可持续发展的角度探讨政策EIA中公众参与的目的、意义、方法和特点,并介绍和分析国家有毒化学品立法EIA开始阶段中的公众参与。 相似文献
123.
Allan J. Perkins Hywel E. Maggs Jeremy D. Wilson 《Agriculture, ecosystems & environment》2008,126(3-4):189-194
To assess the effectiveness of over-winter seed provision by agri-environment schemes, bird use of patches of seed-bearing crops was compared with that of other seed-rich habitats on 53 farms in eastern Scotland over three winters. Seed-bearing crops were the most frequently selected habitat, and held 28% of birds of the 10 species recorded. Outside schemes, cereal stubble was the most selected habitat and held 44% of birds. For nine species, seed-bearing crops were used by more birds than expected from the area of crop available in at least one winter, and five species were more likely to occur in first-winter patches, reflecting a greater abundance of cereal grain than in second-winter patches. For cereal grain specialists such as buntings, sowing cereal-based crops annually would ensure that grain is available in each winter, whilst either a 1-year or a 2-year crop would be appropriate for finches that favour oilseeds, and species with a more generalist diet. 相似文献
124.
国家先后编制了七次科技发展规划,资源科学研究也从最初的自然资源综合考察发展成了一门综合性交叉学科。其中以《1956-1967年科学技术发展远景规划》和《1978-1985年全国科学技术发展规划纲要》,对资源科学的形成与发展影响最大。前者推动了中国自然资源综合考察事业的形成与发展,后者促进了中国资源科学考察事业的发展与壮大,进而推动了资源科学的形成与发展。全文在回顾与展望国家科技发展规划与中国资源科学发展的基础上,提出了新世纪初期国家中长期科学技术发展规划有关资源科学发展的3条建议。 相似文献
125.
Dicky Simorangkir 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):147-164
During the last two decades Indonesia has experienced immense forest and land fires. Often these fires are associated with
extended drought and widespread use of fire to clear previously logged forest and other degraded land in preparation for oil
palm, rubber, or pulpwood plantations. There are many reasons for the use of fire in land clearing activities, but probably
the most important one is economics. There is still acceptance that fire is the cheapest, fastest, and most effective land
clearing method with the added benefit of providing nutrients from ash residues.
This paper provides a review of existing information on the financial costs and benefits of using fire for land clearing in
agriculture and forestry plantations as compared with zero-burning techniques. The findings indicate that the economic advantage
of fire use varies widely and depends on many factors, such as soil fertility, vegetation density, labour cost, equipment
and training costs, and the costs of fire management. For large-scale land clearing, the financial analysis of the costs and
benefits of fire versus zero-burning shows that when applied to low-volume vegetation, zero-burning methods are not more expensive
than burning – and may actually be more cost effective in the long term. This is the case for clearing oil palm or rubber
plantations for replanting, low secondary vegetation, and heavily logged-over forest. Under high-volume forest conditions,
burning remains less expensive because it is more difficult, time consuming, and costly to dispose of high volumes of piled
wood mechanically. 相似文献
126.
127.
128.
揭示了农业污染纠纷的内涵,提出了处理农业污染纠纷的4个“支撑点”,即运用农业技术先行界定,运用监测数据科学鉴证;运用因果关系逻辑推定,强化环境管理,疏通综合处理渠道等。 相似文献
129.
机场噪声环境影响评价的程序和方法 总被引:2,自引:0,他引:2
就机场噪声环境影响评价的程序和常用的预测公式进行了介绍,并将飞机噪声实测和预测结果进行了对照,取得了较为满意的结果。 相似文献
130.
Nowadays, more people tend to spend their recreational time in large national parks, and trace metal(loid)s in soils have attracted long-term attention due to their possible harm to human health. To investigate the pollution levels, potential sources and health risks of trace metal(loid)s in road soils, a total of eight trace metal(loid)s (including As, Cd, Cr, Cu, Ni, Pb, Zn and Hg) from 47 soil samples along roads were studied in the Huangshan National Park in Southeast China. The results showed that the concentrations of As, Cd, Pb, Zn and Hg appeared different degrees of pollution compared with their corresponding background values. According to the pollution indices, Hg and Cd were recognized as significant pollutants presenting moderate to high ecological risk. Combining principal component analysis and positive matrix factorization model, the results showed that traffic, industrial, agricultural and natural sources were the potential origins of trace metal(loid)s in this area, with contribution rates of 39.93%, 25.92%, 10.53% and 23.62%, respectively. Non-carcinogenic risks were all negligible, while the carcinogenic risk of As was higher than the limit (1 10−6). Moreover, children were more susceptible to trace metal(loid)s by ingestion which appeared to be a more important exposure pathway than dermal contact and inhalation. The contribution rates of different sources to non-carcinogenic risks and carcinogenic risks were similar among children and adults, while traffic and industrial sources have a significant impact on health risks. This study will give more insights to control the environmental risks of trace metal(loid)s in national parks. 相似文献