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561.
在当前我国城市化进程和西部大开发的时代背景中,历史文化名城阆中具有一定的代表性,集中地凸现着历史遗产保护与城市发展的矛盾冲突。本文通过对阆中的实地调研,结合可持续发展观,提出了以可持续发展思想为基础的历史文化名城可持续发展的理念。通过分析历史文化名城可持续发展内涵,构建了阆中可持续发展模式,并从保护、经营、传承三方面总结了可持续发展策略。 相似文献
562.
中国的世界自然遗产战略管理研究 总被引:1,自引:0,他引:1
孙克勤 《中国人口.资源与环境》2011,(Z1)
该文介绍了中国的世界自然遗产特征和管理现状,指出了我国的世界自然遗产地管理方面存在的问题,诸如管理体制、地质灾害、生态危机、旅游开发、经济建设、经费匮乏、遗产教育和学术研究滞后等问题。本文还提出了相关保护对策,包括管理体制、遗产保护、遗产教育、保护基金、遗产旅游的建立和实施,以促进中国的世界遗产管理可持续发展。 相似文献
563.
为探究供应链环境协同治理问题,本文从复杂适应系统视角分析了供应链环境协同治理中内部主体之间以及内外部主体间的协同作用机理,以此为基础构建了供应链环境协同治理模型。为探究协同治理机制在该模型中的实际成效,本文运用多主体仿真技术,对二级供应链模型进行仿真模拟,验证了协同治理在企业运营发展以及供应链整体环境绩效方面的提升作用,并针对协同模型中制造商零售商间减排成本分担系数进行调整,检验上下游企业间减排成本分担系数变化对供应链环境治理效果的影响。仿真结果显示,虽然供应链整体利润随着制造商承担的减排成本增加而增加,但供应链单位产值排放量却随之呈现先下降后上升的趋势,进一步验证了协同治理的效果。 相似文献
564.
采用自适应模糊C均值聚类(FCM)挖掘土壤重金属的污染程度信息,以实现污染程度分类数的自动获取,确保类别划分的合理性,真实地反映重金属污染的空间聚集特征.以江苏省南京市炼油厂及生活区为研究对象,采集土壤中Cr、Cd、Ni、Pb、Zn、Cu重金属浓度值,首先运用自适应FCM对浓度值进行聚类分析,然后利用地统计学空间插值,揭示污染的空间聚集性.结果表明,研究区存在不同程度的污染,自适应FCM算法比传统聚类算法能更合理地划分重金属污染程度,挖掘出样本潜在的污染信息,可为分析污染成因及土壤环境治理修复提供参考. 相似文献
565.
566.
水污染治理策略的有效制定对于环境保护事业的顺利开展以及我国人民的健康生活具有重要意义,同时,水污染问题会直接影响我国社会经济的可持续发展。本文首先对水污染危害作出简要阐述,然后对环境保护中水污染的治理问题进行分析,最后结合实际情况,针对水污染治理问题产生的主要原因,提出几点环境保护中水污染的治理策略,希望可以对业内起到一定参考作用。 相似文献
567.
Stormwater ponds are commonly used in residential and commercial areas to control flooding. The accumulation of urban contaminants in stormwater ponds can lead to a number of water quality problems including high nutrient, chemical contaminant, and bacterial levels. This study examined the interaction between land use and coastal pond water quality in a South Carolina residential subdivision pond. Eutrophic levels of chlorophyll and phosphorus were present in all seasons. Harmful cyanobacterial blooms were prevalent during the summer months. Microcystin toxin and fecal coliform bacteria levels were measured that exceeded health and safety standards. Low concentrations of herbicides (atrazine and 2,4-D) were also detected during summer months. Drainage from the stormwater pond may transport contaminants into the adjacent tidal creek and estuary. A survey of residents within the pond's watershed indicated poor pet waste management and frequent use of fertilizers and pesticides as possible contamination sources. Educational and outreach activities were provided to community members to create an awareness of the water quality conditions in the pond. Pond management strategies were then recommended, and selected mitigation actions were implemented. Water quality problems identified in this study have been observed in other coastal stormwater ponds of varying size and salinity, leading this project to serve as a potential model for coastal stormwater pond management. 相似文献
568.
Environmental and genetic determinants of the male forceps length dimorphism in the European earwig Forficula auricularia L. 总被引:1,自引:0,他引:1
J. L. Tomkins 《Behavioral ecology and sociobiology》1999,47(1-2):1-8
Male dimorphisms are particularly conspicuous examples of alternative reproductive strategies. The male forceps length dimorphism
in the European earwig Forficula auricularia has long been considered an example of a status- (body size) dependent male dimorphism. In this paper, I test three hypotheses
relating to the dimorphism of F. auricularia. First, that the dimorphism is status dependent and determined by nutrition. Second, that the dimorphism is a density-dependent
adaptation. Third, that there is a genetic basis to population differences in morph frequency seen in the field. These hypotheses
were tested by rearing two populations in a split-family rearing design with two diets and two densities. Populations of male
earwigs reared in the common garden differed in forceps length and relative forceps length. The populations also differed
in the morph frequencies, with 40 versus 26% long-forceped males. These results confirm the notion that there is a genotype-by-environment
interaction that determines the morph frequency in a population. There were only minor effects of density on male forceps
length and no influence of density on the male dimorphism. In accordance with the hypothesis that the morphs are status-dependent
alternatives, large-forceped males only arose on the high-protein diet that produced earwigs of a large body size. However,
not all large males produced the long-forceped phenotype. I put forward an extension of the status-dependent dimorphism model
that may account for the pattern of forceps dimorphism in this species.
Received: 18 November 1998 / Received in revised form: 14 May 1999 / Accepted: 25 July 1999 相似文献
569.
Male reproductive success in free-ranging feral horses 总被引:1,自引:0,他引:1
C. S. Asa 《Behavioral ecology and sociobiology》1999,47(1-2):89-93
In the social organization of feral horses, adult males compete to monopolize groups or bands of females, sometimes called
harems. Alternative male strategies are to remain alone or with other bachelors or, less commonly, to accept subordinate status
within a harem. The hypothesis that dominant harem stallion status confers a reproductive advantage was tested in free-ranging
feral horses. The presence of foals in harems headed by vasectomized (VSX) versus intact stallions was used to assess the
ability of these stallions to control reproduction in their harems. Of harems headed by VSX stallions, 17 and 33% contained
foals during years 2 and 3 post-treatment, respectively. In contrast, 86 and 80% of harems headed by non-VSX stallions contained
foals in those years. Acquisition of pregnant mares appeared more likely than sneak copulations by bachelor stallions to account
for foals in harems with a single stallion. However, most foals were born into harems that included a subordinate stallion,
an occurrence that was undoubtedly exacerbated by the extended breeding season resulting from the sterility of the harem stallion.
Thus, in comparing alternative reproductive tactics, bachelors appeared less successful than subordinate stallions within
a harem. However, the highest reproductive success was achieved by the harem stallion, further demonstrating that alternative
tactics are not equally profitable.
Received: 13 July 1999 / Received in revised form: 24 July 1999 / Accepted: 24 July 1999 相似文献
570.
This paper examines the problems associated with inter-organisational learning and adaptation in the dynamic environments that characterise disasters. The research uses both qualitative and quantitative methods to investigate whether organisational learning took place during and in the time in between five disaster response operations in Turkey. The availability of information and its exchange and distribution within and among organisational actors determine whether self-adaptation happens in the course of a disaster response operation. Organisational flexibility supported by an appropriate information infrastructure creates conditions conducive to essential interaction and permits the flow of information. The study found that no significant organisational learning occurred within Turkish disaster management following the earthquakes in Erzincan (1992), Dinar (1995) and Ceyhan (1998). By contrast, the 'symmetry-breaking' Marmara earthquake of 1999 initiated a 'double loop' learning process that led to change in the organisational, technical and cultural aspects of Turkish disaster management, as revealed by the Duzce earthquake response operations. 相似文献