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661.
This paper evaluates the feasibility of establishing a multiple-use marine protected area. The methodology was applied to evaluate three proposed sites in Chile with diverse conservation needs, social stress and poverty levels, and different economic activities (small-scale fishing, heavy industry, and mining activities). We use two broad categories for the evaluation: socio-economic and political–institutional. The methodology uses a combination of secondary data with personal interviews, workshops, and focus groups with stakeholders (e.g., fishermen, unions, politicians, social organizations) from different political, social, and economic backgrounds to characterize current and potential natural and social resources and to evaluate in an ordinal scale the feasibility of establishing the protected area. The methodology allows us to correctly identify the challenges faced in each site and can be used to develop appropriate strategies for balancing economic, social, and environmental objectives. This methodology can be replicated to evaluate the feasibility of other marine or terrestrial protected areas. 相似文献
662.
饮用水功能区水环境健康风险阈值体系研究 总被引:1,自引:0,他引:1
结合天津市饮用水功能区水环境现状,筛选出14种特征污染物,通过危害识别将其分为化学致癌物、非致癌有毒物和特殊物质3类。针对不同类别污染物建立健康风险评价模型,给出化学致癌物的致癌强度系数、非致癌有毒物参考剂量、人均寿命、不同年龄段人群日均饮水量和平均体重等参数,建立针对不同人群的饮用水功能区水质风险阈值体系。在此基础上,对天津市饮用水功能区——于桥水库进行水质风险进行评价。结果显示,于桥水库国控监测点位10个监测指标中,氨氮、挥发酚、汞、铅具有健康风险,4个指标的浓度均处于10-7的风险水平以下,说明于桥水库水环境健康程度较好,4个指标对成人及儿童的风险水平排序为铅氨氮汞挥发酚,重金属铅是主要健康风险污染物。 相似文献
663.
A study was performed selecting one protected forest and an adjacent degraded forest ecosystem to quantify the impact of forest
degradation on soil inorganic nitrogen, fine root production, nitrification, N-mineralization and microbial biomass N. There
were marked seasonal variations of all the parameters in the upper 0–10 and lower 10–20 cm depths. The seasonal trend of net
nitrification and net N-mineralization was reverse of that for inorganic nitrogen and microbial biomass N. Net nitrification,
net N-mineralization and fine root biomass values were highest in both forests during rainy season. On contrary, inorganic
nitrogen and microbial biomass N were highest during summer season.
There was a marked impact of forest degradation on inorganic nitrogen, fine root production nitrification, N-mineralization
and microbial biomass observed. Soil properties also varied with soil depth. Fine root biomass, nitrification, N-mineralization
and microbial biomass N decreased significantly in higher soil depth. Degradation causes decline in mean seasonal fine root
biomass in upper layer and in lower depth by 37% and 27%, respectively. The mean seasonal net nitrification and N-mineralization
in upper depth decreased by 42% and 37%, respectively and in lower depth by 42.21% and 39% respectively. Similarly microbial
biomass N also decreased by 31.16% in upper layer 33.19% in lower layer. 相似文献
664.
陈印军 《中国人口.资源与环境》2000,10(2):52-53
在党中央和国务院的关怀下 ,西部大开发的序幕即将拉开 ,全国人民为之振奋。如何保障西部大开发的顺利实施 ?本文认为必须转变传统观念 ,实施新的开发战略。 相似文献
665.
666.
Eco-restoration: Simultaneous nutrient removal from soil and water in a complex residential-cropland area 总被引:3,自引:0,他引:3
Yonghong Wu Philip G. Kerr Linzhang Yang 《Environmental pollution (Barking, Essex : 1987)》2010,158(7):2472-2477
An eco-restoration system to remove excess nutrients and restore the agricultural ecosystem balance was proposed and applied from August 2006 to August 2008 in a residential-cropland complex area (1.4 × 105 m2) in Kunming, western China, where the self-purifying capacity of the agricultural ecosystem had been lost. The proposed eco-restoration system examined includes three main foci: farming management, bioremediation, and wastewater treatment. The results showed that the removal efficiencies of total phosphorus (TP) and total nitrogen (TN) from the complex wastewater were 83% and 88%, respectively. The Simpson’s diversity indices of macrophytes and zoobenthos indicated that the system had increased macrophyte and zoobenthic diversity as well as improved growth conditions of the plankton habitats. The results demonstrated that the proposed eco-restoration system is a promising approach for decreasing the output of nutrients from soil, improving agricultural ecosystem health, and minimizing the downstream eutrophication risk for surface waters. 相似文献
667.
668.
针对农村生活污水的特点,设计叠层生态滤床,并将其应用于浙西山区农村生活污水的处理。运行结果表明,系统出水的COD、氨氮、总氮、总磷质量浓度分别为18.20、0.492、0.77、0.129 mg/L,去除率分别达到43.30%、56.42%、42.11%、19.88%,出水的COD、氨氮、总氮、总磷均满足《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准。叠层生态滤床处理农村生活污水的吨水投资成本较低,后期运行基本不产生费用,而且在后期管理上不需要配备专门的技术人员,适用于不同经济发展程度农村的生活污水处理,具有良好的推广价值。 相似文献
669.
旅游景区经营权转让失败的制度根源剖析——以贵州马岭河景区为例 总被引:1,自引:0,他引:1
近年来,转让经营权成为一些风景名胜区管理和经营改革过程中引入企业化经营的一种制度创新模式。贵州马岭河作为全国首个实行风景名胜区内项目特许经营管理的试点单位,却在经营权转让后仅一年便以企业的退出而宣告失败。基于制度层面对马岭河景区转让失败的深层次原因进行探讨,并就如何规避景区市场化运作过程中的经营管理风险和负面影响提出相关对策,旨在为我国相关旅游地的开发提供有益的实践参考和理论借鉴。 相似文献
670.
Jeffrey S. Brown Martha Sutula Chris Stransky John Rudolph Earl Byron 《Journal of the American Water Resources Association》2010,46(2):367-385
Brown, Jeffrey S., Martha Sutula, Chris Stransky, John Rudolph, and Earl Byron, 2010. Sediment Contaminant Chemistry and Toxicity of Freshwater Urban Wetlands in Southern California. Journal of the American Water Resources Association (JAWRA) 46(2):367-384. DOI: 10.1111/j.1752-1688.2009.00407.x Abstract: Wetlands provide many critical functions in urban ecosystems, including habitat for wetland-dependent fauna and enhancement of water quality. Interest in restoring or creating wetlands to enhance these functions is increasing due to the scale and extent of wetland loss and water quality problems associated with urbanization. One of the most pressing questions associated with urban wetland restoration is the extent to which urban wetlands tend to concentrate contaminants, and if so, whether an associated risk to wildlife exists. The goal of this study was to better understand these potential risks, and the associated tradeoffs with using wetlands to treat urban runoff. Sediment toxicity, contaminant chemistry, and macroinvertebrate (MI) community metrics were measured in 21 southern California wetlands that receive urban runoff as their primary water source. MI organisms in 18 of the 21 urban wetlands examined were considered to be at risk due to sediment contaminant concentrations and toxicity. Most of the sites were either toxic to the amphipod Hyalella azteca, exceeded a sediment quality guideline, or both. Sediment chemistry and toxicity identification evaluation studies suggest that pyrethroid pesticides may have been responsible for much of the toxicity documented in this study. The mean Probable Effects Concentration quotient (an index of degree of sediment contamination) was found to negatively correlate with MI diversity in these wetlands suggesting that toxicity was affecting organisms at the base of the food chain in these wetlands. 相似文献