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911.
Multinational,Freshwater Biomonitoring Programs in the Developing World: Lessons Learned from African and Southeast Asian River Surveys 总被引:2,自引:1,他引:1
Resh VH 《Environmental management》2007,39(5):737-748
Biomonitoring programs are widely used in developed countries. They also offer many advantages in assessing ecological consequences
of perturbations in developing countries, including reducing the equipment-operation, maintenance, and training costs associated
with physicochemical monitoring. Three case histories of river biomonitoring using freshwater organisms (fish, benthic macroinvertebrates,
diatoms, zooplankton) are described that involve (1) documentation of environmental effects from long-term, large-scale applications
of insecticides to control insect-vectors of river blindness (onchocerciasis) in 11 West African countries; (2) water quality
assessments and restoration planning in and around national parks in three East African countries; and (3) evaluation of overall
ecological health of the Lower Mekong River in four Southeast Asian countries. As in developed countries, benthic macroinvertebrates
are the organisms most widely used in biomonitoring in developing countries. Conflicting opinions of system resilience and
whether expected changes are within natural variation may result in differences in underlying hypotheses proposed, study designs
implemented, and study execution; each may lead to uncorrectable bias. Direct transfers of approaches used from developed
to developing countries are often appropriate; however, techniques dependent on pollution-tolerance values are often region
specific and not transferable. Typically expressed concerns about applications of biomonitoring in developing countries include
poor coordination among agencies; lack of legislation, identification keys, and trained personnel; and incomplete information
on how tropical rivers function. Problems are real but solvable, as evident from accomplishments in several multicountry programs
in developing countries. Developed countries requiring coordinated monitoring of international rivers may benefit from examining
successful programs under way in developing countries. 相似文献
912.
为探究特定水环境中多因子影响下的铜水质基准及生态风险,采用物种权重敏感度分布法、水效应比法和生物配体模型推导保护太湖水生生物铜的水质基准.根据推导结果,推荐采用最大浓度基准值(CMC)1.43 μg/L和持续浓度基准值(CCC)1.33 μg/L.结合水效应比法和生物配体模型,采用联合概率法评估太湖铜的生态风险.结果表明,两种方法下丰水期5%水生生物受到铜慢性毒性影响的概率分别为23.43%和39.43%,而未考虑多因子影响的风险概率为85.01%,高估了太湖铜生态风险.可见,水环境多因子对水质基准和生态风险的影响不容忽视,我国目前使用的铜标准可能无法保护特定区域的水生生物.考虑多因子影响可提高基准值推导和风险评估的科学性,避免"过保护"和"欠保护"现象. 相似文献
913.
914.
Nolberto Munier 《Environment, Development and Sustainability》2006,8(3):425-443
This paper presents a multicriteria method to treat difficult EIA problems where several alternatives or options are to be
gauged through many different types of criteria. To illustrate the method a case example for an urban road project is proposed
involving 14 criteria and comprising government, public opinion, social, environment, infrastructure and economic issues,
and in accordance with a chosen objective. This example tries to demonstrate that equilibrium can be reached between economic
growth and sustainable development. Although the proposed example as a whole does not depict a real life application, its
components have been tested in actual situations and in different countries.
Dichotomy: Division into two usually contradictory parts or opinions.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
915.
本文论述了自然保护区评价这一新学科在近30年内的发展史,同时介绍了自然保护区评价的几个组成部分和一些基本概念,分析了其存在的不足和有待解决的问题。 相似文献
916.
The purpose of our research was to identify shrub species growing in southern Quebec that inhibit ecological succession in
power-line corridors. Results are presented in three parts. First, clonal characteristics that allowed the establishment of
stable communities were identified. Second, successional vector analysis identified those species that have the potential
to inhibit succession. In poorly drained sites those species wereCornus stolonifera, C. obliqua, Salix petiolaris, andSpiraea alba. In well-drained sites, those species wereZanthoxylum americanum, Rubus idaeus, Spiraea alba, Rhus typhina, andThuja occidentalis. Third, analysis of variance showed that there is a significantly larger number of tree seedlings found in adjacent herbaceous
communities than found under the dense cover ofCornus stolonifera, C. obliqua, Salix petiolaris, Spiraea alba, Rhus typhina, Rubus idaeus, Thuya occidentalis, andZanthoxylum americanum. These results indicate that the planting of selected shrub species could, through biological control, delay reforestation. 相似文献
917.
水质基准是制定水质标准的重要科学依据,制定符合我国实际情况的水质基准已成为当前的迫切需求.BPA(bisphenol A,双酚A)是一种典型的内分泌干扰物,基于太湖流域的人群暴露参数和生物累积系数,采用HJ 837-2017《人体健康水质基准制定技术指南》推荐方法,推导出太湖BPA的人体健康水质基准为0.738 μg/L,通过太湖儿童暴露参数得到保护儿童BPA的人体健康基准为0.628 μg/L(6~ < 9岁)、0.821 μg/L(9~ < 12岁)、0.620 μg/L(12~ < 15岁),与成人基准差异不大.基于太湖流域水生生物的毒性数据,采用SSD(species sensitivity distribution,物种敏感度分布)法得到水生生物慢性基准为0.189 μg/L.使用RQ(risk quotient,风险商值)法评价太湖水体中BPA暴露所造成的健康与生态风险,结果表明,太湖中有0.03%区域面积水体存在较高健康风险,有2.03%区域面积水体存在较高的生态风险.另外,采用联合概率曲线法进一步分析生态风险发现,太湖水体中BPA对1%与5%的水生生物造成危害的概率分别为0.71%和0.33%.研究显示,我国太湖水体中BPA暴露造成的健康与生态风险处于可接受水平. 相似文献
918.
This study aims to investigate the effect of a magnetic field on nitrous oxide(N_2O) emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N_2O for a magnetic field-sequencing batch reactor(MF-SBR) decreased by34.3% compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN) and ammonia nitrogen(NH4-N) of the MF-SBR were 22.4% and 39.5% higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira) and denitrifiers(Zoogloea),which could reduce N_2O to N_2,were promoted significantly in the MF-SBR.Enzyme activities(Nir) and gene abundances(nos Z nir S and nir K) for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N_2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature. 相似文献
919.
污水生物处理中微生物的相互协作 总被引:2,自引:0,他引:2
从化学、物理和遗传信息三个不同水平,系统介绍了污水生物处理中微生物的相互协作关系,阐述了各个水平的协作机制、应用研究进展以及存在问题 相似文献
920.
荒漠生态环境监测指标体系初探 总被引:1,自引:0,他引:1
讨论了建立荒漠生态环境监测指标体系应遵循的五个原则,并提出初步的荒漠生态环境监测指标体系,将指标体系分为三个部分:(1)荒漠环境指标;(2)荒漠生物指标;(3)社会经济指标. 相似文献