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371.
372.
水源地是城市水资源可持续供给的重要空间载体。伴随城市化的快建发展,城市水资源供求压力日起紧张,城市水源地在保障城市水资源可持续供给方面的作用日益突出。本文从城市化过程中的水资源需求变化出发,揭示水源地在城市可持续发展中的战略地位,评析我国水桓交易的理论研究进展,在此基础上提出我国城市水源地建设保护过程中水权交易的走势判断。 相似文献
373.
Identification and spatial patterns of coastal water pollution sources based on
GIS and chemometric approach 总被引:1,自引:0,他引:1
Comprehensive and joint applications of GIS and chemometric approach were applied in identification and spatial patterns of coastal water pollution sources with a large data set (5 years (2000-2004), 17 parameters) obtained through coastal water monitoring of Southern Water Control Zone in Hong Kong. According to cluster analysis the pollution degree was significantly different between September-next May (the 1st period) and June-August (the 2nd period). Based on these results, four potential pollution sources, such as organic/eutrophication pollution, natural pollution, mineral/anthropic pollution and fecal pollution were identified by factor analysis/principal component analysis. Then the factor scores of each monitoring site were analyzed using inverse distance weighting method, and the results indicated degree of the influence by various potential pollution sources differed among the monitoring sites. This study indicated that hybrid approach was useful and effective for identification of coastal water pollution source and spatial patterns. 相似文献
374.
大麦秸秆化感作用方法对农村饮水水源的藻类控制分析 总被引:1,自引:0,他引:1
就缺水地区农村饮水水源中藻类控制,介绍了生物化感作用这一处理方法及其原理,提出使用大麦秸秆来进行农村小型池塘的藻类控制方法。实验结果表明,此方法操作简便、效果明显,并具有管理维护简单、运行费用低廉等优势,值得在农村或山区等缺水地区大力推广。 相似文献
375.
Grochowalski A Lassen C Holtzer M Sadowski M Hudyma T 《Environmental science and pollution research international》2007,14(5):326-332
Background The aim of the project was to measure the actual emissions of PCDD/F, PCBs and HCB from 20 selected metallurgical installations
in Poland, in order to update the national inventory of dioxin emission from metallurgical industry for developing a strategy
for dioxins and furans emission abatement from the subject facilities (UNEP 2005).
Methods Sampling methodology used in this work was developed at the Cracow University of Technology because of the complexity of simultaneous
sampling and determining PCDFs, PCDDs, PCB and HCB. For the determination a GC-MS/MS system was used.
Results and Discussion Results from the work indicate that the highest dioxins and PCB concentrations were recorded for iron ore sintering plants
at 1.10–1.32 ng total1 TEQ/Nm3 followed by aluminium scrap melting at 0.03–0.66 ng total TEQ/Nm3. The highest HCB concentrations at 613–1491 ng/Nm3 were also recorded for iron ore sintering plants, whereas at aluminium plants the HCB concentrations were in the range of
only 10.1–22.7 ng/Nm3.
Conclusions The above investigations indicate that secondary aluminium production is the most significant dioxins source, if calculated
as emission factor values. However, iron ore sintering plants are operating at much higher production capacity, causing this
process to become the major source of dioxins, PCB and HCB pollution to the atmosphere in Poland.
Recommendations and Perspectives Based on the performed tests and the environmental reviews of selected plants several recommendations were formulated for
the reduction of generation or of emission of these pollutants from iron ore sintering plants, electric arc furnace steel
production processes, hot-blast furnace operations, secondary aluminium smelting and primary zinc production from zinc cathodes. 相似文献
376.
Yuceil K Tanik A Gurel M Seker DZ Ekdal A Erturk A Gonenc EI 《Environmental monitoring and assessment》2007,128(1-3):465-474
Soil is an important component of a watershed. Understanding soils and their interactions with the other components are, thus,
considered to be critical and essential for conservation of resources and management of the watershed. Development of soil
sampling and analysis programs are crucial for these purposes. Site-specific soil data are needed to identify current soil
characteristics, as well as to validate datasets gathered for watershed-scale modelling of non-point sources (NPS) of pollutants
arising from various land-use activities, hydrodynamics and water quality. The Koycegiz Lake–Dalyan Lagoon watershed, located
in the southwest of Turkey along the Mediterranean Sea Coast, was selected as the study area for watershed modelling purposes.
Development of soil sampling plans, their practical optimization, soil analyses and interpretation are presented in this article.
The soil analyses conducted include physical, chemical and specific soil characteristics. Within the framework of this study,
soil fertility parameters are presented and evaluated. Such an approach used is recommended for especially developing countries
where up-to-date data sets are not fully available and/or centrally publicized. 相似文献
377.
参数空间分布对非点源污染模拟的影响 总被引:4,自引:0,他引:4
以大宁河流域为研究区域,应用非点源模型SWAT(soil and water assessment tool),模拟了参数空间分布对流域径流和营养物质流失的影响.利用大宁河流域巫溪水文站2000~2004年的实测数据对模型进行了率定和验证,将流域划分为6种数量不等的子流域,利用相同的模型参数输入,模拟了不同的流域划分方案对径流和营养物质流失的影响.结果表明,不同的流域划分方案,年平均流量的最大相对误差为19.6%,6种方案年平均流量的效率系数为0.52~0.82,月平均流量的效率系数为0.80~0.83,随着子流域数量的增加,径流量出现了先下降、后上升的趋势;有机氮和有机磷的最大相对误差分别为16.2%和7.7%,不同的流域划分方案对营养物质的流失产生了轻微的影响,但没有明显的变化趋势和规律. 相似文献
378.
379.
This paper explains how the well-accepted concept of improved stakeholder participation during mineral policy development leads to a national mineral policy that accommodates the diverging views and interests that allows wide acceptance of decisions, enhancing the success of implementation and, ultimately, national benefits. This process is based on lessons learnt during the South African experience and has been successfully applied in the development of the Namibian and Malawian national minerals policies. An effective policy in the SADC will engineer the delicate balance between poverty reduction and an internationally competitive minerals sector. This balance enhances the possibility of long-term economic growth and development in the SADC region. The overriding advantage of this strategy is that it generates ‘home-grown’ policy instruments and implementation of mineral law with which stakeholders can identify. This process presents a new challenge to traditional policy formulation strategies in emerging economies and the bottom-up approach, linked to wide political support, allows the potential realisation of national objectives. 相似文献
380.
Evaluators frequently cite the absence of effective participation by constituent governments and the need for consensus or even unanimity prior to action as the causes of poor performance by regional resource management institutions. Major governments either will not join the regional institution, will not participate even if legally members, or will exercise a veto over many important management projects.This paper examines the variables that may cause these problems and provides an improved understanding of why rational political actors would act in ways that inhibit the efficient management of resources. Among the principal variables determining participation are expected benefits of collective decisions, perceived losses of autonomy and representation, the number and homogeneity of other participants, decision costs, and the decision rule used to determine actions. Analysis of these factors suggests why consensus and unanimity decision rules are frequently chosen and why participation is usually limited. 相似文献