全文获取类型
收费全文 | 1988篇 |
免费 | 70篇 |
国内免费 | 86篇 |
专业分类
安全科学 | 130篇 |
废物处理 | 18篇 |
环保管理 | 237篇 |
综合类 | 1175篇 |
基础理论 | 121篇 |
污染及防治 | 121篇 |
评价与监测 | 265篇 |
社会与环境 | 45篇 |
灾害及防治 | 32篇 |
出版年
2024年 | 5篇 |
2023年 | 18篇 |
2022年 | 27篇 |
2021年 | 41篇 |
2020年 | 49篇 |
2019年 | 29篇 |
2018年 | 24篇 |
2017年 | 48篇 |
2016年 | 52篇 |
2015年 | 73篇 |
2014年 | 82篇 |
2013年 | 98篇 |
2012年 | 123篇 |
2011年 | 136篇 |
2010年 | 87篇 |
2009年 | 109篇 |
2008年 | 93篇 |
2007年 | 119篇 |
2006年 | 137篇 |
2005年 | 97篇 |
2004年 | 70篇 |
2003年 | 92篇 |
2002年 | 67篇 |
2001年 | 66篇 |
2000年 | 59篇 |
1999年 | 60篇 |
1998年 | 56篇 |
1997年 | 61篇 |
1996年 | 32篇 |
1995年 | 34篇 |
1994年 | 28篇 |
1993年 | 32篇 |
1992年 | 14篇 |
1991年 | 5篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1973年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有2144条查询结果,搜索用时 828 毫秒
741.
742.
Ingemar Renberg Christian Bigler Richard Bindler Matilda Norberg Johan Rydberg Ulf Segerström 《Journal of environmental management》2009
Establishment of plans for environmental planning and management requires that a number of natural and societal factors must be taken into consideration. Insights into the inherent dynamics of nature as well as the role that past human activities have played for establishing the current condition of the landscape and the natural environment in general are essential. Many natural and man-made changes occur over time scales of decades or centuries, and these are difficult to comprehend without a historical perspective. Such a perspective can be obtained using palaeoecological studies, i.e. by geochemical and biological analyses of lake sediment and peat deposits. To illustrate the long-term dynamics of nature and particularly the role of man, we present here five case studies from Sweden concerning pollution, lake acidification, lake eutrophication, biodiversity, and landscape dynamics and conservation – topics of broad interests – and discuss benefits of including a longer time perspective in environmental management. 相似文献
743.
China's water scarcity 总被引:1,自引:0,他引:1
China has been facing increasingly severe water scarcity, especially in the northern part of the country. China's water scarcity is characterized by insufficient local water resources as well as reduced water quality due to increasing pollution, both of which have caused serious impacts on society and the environment. Three factors contribute to China's water scarcity: uneven spatial distribution of water resources; rapid economic development and urbanization with a large and growing population; and poor water resource management. While it is nearly impossible to adjust the first two factors, improving water resource management represents a cost-effective option that can alleviate China's vulnerability to the issue. Improving water resource management is a long-term task requiring a holistic approach with constant effort. Water right institutions, market-based approaches, and capacity building should be the government's top priority to address the water scarcity issue. 相似文献
744.
745.
工业复合源大气污染长期扩散浓度模拟计算 总被引:1,自引:0,他引:1
在工业复合源大气扩散模式研究的基础上,改造传统大气污染物长期扩散模型,引入了平滑函数,使相邻扇区的交界处具有连续性,提出了计算精度。对于复合源采用坐标变换的方法,解决不同种类,多源污染物季平均浓度值叠加的难题。 相似文献
746.
During the past 25 years, the management of marine ecosystems has evolved significantly. Due to the increased use of the sea
and the increased awareness of adverse impacts of certain human activities in and around the sea, which has been a common
good for a long time—‘Mare Liberum’—an international and integrated approach has become increasingly important to regulate
the use of our common seas.
From the late 1960s onwards, intergovernmental meetings have taken place in order to tackle the problems of international
pollution of seas and oceans. One reason for this attention was the Torrey Canyon accident in 1967, which triggered the start
of the Bonn Agreement in 1969 for coordinating the combat mission against oil and chemical spills in the North Sea.
After the 1972 United Nations Conference on the Human Environment in Stockholm, with the involvement of the European Union,
the International Council for Exploration of the Sea (ICES) and Non-Governmental Organizations (NGOs), other regional and
global Conventions, as well as the North Sea Ministerial Conferences were established.
These continuous international efforts have resulted in a considerable reduction of the input of certain contaminants and
of nutrients (in particular phosphate) into the marine environment. However, not all problems have yet been solve. The North
Sea Ministers agreed at the Conference in Esbjerg (1995) to aim at a reduction of the input of all hazardous substances within
one generation, in order to reach the goal of negligible risks of pollution. Furthermore, there is a general aim to minimize
adverse effects of disturbing activities. The challenge, now and in the future, is to find a balance between economic development
and environmental protection of our international marine waters aiming at a sustainable development of the marine resources
by employing scientifically based measures and, in situations where there are reasonable grounds for concern but no conclusive
links between cause and problem, applying the precautionary principle with respect to pollution and disturbing activities. 相似文献
747.
三峡库区面源污染现状与对策研究 总被引:34,自引:4,他引:34
三峡库区生态环境脆弱,坡耕地垂直分布明显,耕地利用方式不合理,库区耕地环境质量较差。水土流失严重。库区沿江工厂星落棋布,落后的生产工艺和小规模生产,使大量废水没经处理直接排放到库区各大河流。虽然目前长江流域水体的自净作用能将污水稀释,但随着三峡大坝的正式蓄水,部分区域水体污染将不可避免。通过对库区部分区域水体近几年的连续监测,水体总P、非离子氨、CODcr等指标有恶化趋势。库区土壤重金属监测结果表明,土壤重金属Cd、As含量明显增加,并且远大于当地土壤背景值。库区农畜产品蔬菜、茶叶、鱼Pb、Cd超标较严重。土壤N、P流失率较高。有效防止库区面源污染的对策一方面是控制工业点源、线源污染造成的面源污染.另一方面是控制农业自身造成的面源污染。主要措施有:加强库区环境管理和环保宣传力度;建立沿江生物隔离带;加强土地管理,加大农业工程投入,合理利用土地;大力提倡水土保持耕作法;扩大森林覆盖率,建立坡地立体复合农业生态系统:建立面源污染预警系统。 相似文献
748.
Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of Haihe River, Tianjin, China 总被引:7,自引:0,他引:7
JIANG Bin ZHENG Hai-long HUANG Guo-qiang DING Hui LI Xin-gang SUO Hong-tu LI Rui 《环境科学学报(英文版)》2007,19(3):306-311
In this study sediment samples were collected from 13 sites of Haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons (PAHs) listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin. 相似文献
749.
750.