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251.
以福州大学为例,选取3种绿色基础措施(绿色屋顶、植被浅沟、渗透铺装)与2种灰色基础设施(增大管径、蓄水池)组合,设计了9种雨水系统改造措施方案,并根据3场不同历时极端天气降雨的实测数据,运用暴雨洪水管理模型(SWMM)模拟分析不同雨水系统改造措施方案对径流深、节点和管道的雨洪控制效果.情景模拟结果表明:3场强降雨下,绿色基础措施组合(SS7)在所有用地布局情景中对径流深的控制效果均为最优,其中中长历时强降雨下的削减比最高,达到了78%;在节点控制方面,由于3种绿色基础措施与增大管径组合措施(SS8)具备下渗、滞留和快排等特性,在3场降雨中,对节点的洪流流量和洪流时间的控制效果均为最优,接近100%;在管道控制方面,3种含绿色基础措施的组合方案(SS7,8,9)对管道满流时间与峰值流量发生时间的控制较好.通过对比这3种组合措施方案发现,在短历时强降雨中,3种绿色基础措施与蓄水池组合措施方案下(SS9)管道满流时间最短,峰值流量发生时间最迟;中长历时强降雨中3者差别不大;长历时强降雨中3种绿色基础措施组合下(SS7)管道满流时间最短,峰值流量发生时间最迟.  相似文献   
252.
The Dodo was last sighted on the inshore island of Ile d'Ambre in 1662, nearly 25 years after the previous sighting on the mainland of Mauritius. It has been suggested that its survival on the inshore island is representative of the refuge effect. Understanding what constitutes significant persistence is fundamental to conservation. I tested the refuge‐effect hypothesis for the persistence of the Dodo (Raphus cucullatus) on an inshore island beyond that of the mainland population. For a location to be considered a refuge, most current definitions suggest that both spatial and temporal isolation from the cause of disturbance are required. These results suggest the island was not a refuge for the Dodo because the sighting in 1662 was not temporally isolated from that of the mainland sightings. Furthermore, with only approximately 350 m separating Ile d'Ambre from the mainland of Mauritius, it is unlikely this population of Dodos was spatially isolated. Hipótesis del Efecto Refugio y la Desaparición del Dodo  相似文献   
253.
Increase in human settlements at the edge of protected areas (PAs) is perceived as a major threat to conservation of biodiversity. Although it is crucial to integrate the interests of surrounding communities into PA management, key drivers of changes in local populations and the effects of conservation on local livelihoods and perceptions remain poorly understood. We assessed population changes from 1990 to 2010 in 9 villages located between 2 PAs with different management policies (access to natural resources or not). We conducted semi‐directive interviews at the household level (n =217) to document reasons for settlement in the area and villager's attitudes toward the PAs. We examined drivers of these attitudes relative to household typology, feelings about conservation, and concerns for the future with mixed linear models. Population increased by 61% from 2000 to 2010, a period of political and economic crisis in Zimbabwe. Forty‐seven percent of immigrants were attracted by the area; others had been resettled from other villages or were returning to family lands. Attitudes toward PAs were generally positive, but immigrants attracted by the area and who used resources within the PA with fewer restrictions expressed more negative attitudes toward PAs. Household location, losses due to wild animals, and restrictions on access to natural resources were the main drivers of this negative attitude. Profit‐seeking migrants did not expect these constraints and were particularly concerned with local overpopulation and access to natural resources. To avoid socio‐ecological traps near PAs (i.e., unforeseen reduced adaptive capacity) integrated conservation should address mismatches between management policy and local expectations. This requires accounting for endogenous processes, for example, local socio‐ecological dynamics and values that shape the coexistence between humans and wildlife. Percepciones para Conservación Integrada a Partir de las Actitudes de las Personas hacia Áreas Protegidas cerca del Parque Nacional Hwangem Zimbabwe  相似文献   
254.
运用GIS和遥感技术分析了玛曲县1975、1990和2005年的土地利用/覆盖特征,在此基础上使用生态价值系数(C)计算出该县生态系统服务价值.结果表明,该区域1975~2005年间生态系统服务价值从129.713亿元减少到123.961亿元,共损失5.75亿元,且损失量和损失幅度呈持续增加趋势;该区域生态系统服务价值中,废物处理价值最高,气候调节价值次之,原材料价值最低,且30年间各服务类型的价值均呈减小趋势;玛曲县1975、1990和2005年人均生态系统服务价值分别为58.96,42.80,29.51万元,表明玛曲县由于人口的增长,环境压力呈持续增大趋势.草地和湿地退化是导致该区域生态系统服务价值减少的主要原因.CS检验说明本研究所选C值较为合理.  相似文献   
255.
Results of the assessment of enrichment, accumulation and the ecological risk associated with three heavy metals (Cd, Cu and Pb) and one metalloid (As) in surface sediments of Msimbazi estuary are presented. Surface sediment samples (0–5 cm) were collected from Msimbazi River estuary in September 2016 using handheld PVC short corers. Long-sediment cores from the site were also collected using PVC pipes and their vertical profiles of metals concentrations assessed with the aim of establishing site-specific baseline metals concentrations. The established site-specific baseline values were used for the determination of normalised enrichment factors (EF) and geoaccumulation (Igeo) of metals instead of using average crustal values. Iron-based enrichment factors show that the sediments of Msimbazi have experienced enrichment of metals that originate from anthropogenic sources of pollution (EF > 1). Geo-accumulation results indicate that Msimbazi sediments can be designated as uncontaminated to moderately-contaminated with As, Cd and Pb (class 1–2). Geoaccumulation indices for Cu indicate that sediment can be designated as uncontaminated to moderately contaminated (class 1) and moderately to strongly contaminated (class 3). Results show further that the Ecological Risk associated with the accumulation of these metals in Msimbazi sediments was low based on Hakanson approach.  相似文献   
256.
Studies were carried out to determine the toxicity of some selected pesticides on fresh water fish in a tropical environment. The uptake of the pesticides lindane, pentachlorophenol (PCP), and propoxur, which are frequently used by farmers and industrialists were studied in concrete ponds at the University of Cape Coast, in Ghana. The fishes used for the study were Oreochromis niloticus, Clarias gariepinus, and Chrysicthys nigrodigitatus, and were obtained from cultured ponds in the Cape Coast District and Mankessim in the Central Region and Weija Dam, in the Greater Accra region of Ghana. Single high lethal concentration (SD) or acute treatment and cumulative/chronic (or multiple minor) lethal concentration (CD) treatment were employed in administering the pesticides to the fishes via water. Gas chromatograph (GC) Electron Capture Detector (ECD) analysis was done on the dead fishes to see the extent of ingestion. The LC50 values obtained for lindane on the three fish samples were as follows: Chrysicthys?–?0.38?mg?L?1; Oreochromis?–?0.42?mg?L?1, and Clarias?–?1.2?mg?L?1. Mortalities occurred in fish within 3–5 days of application. For the PCP on Chrysicthys, Oreochromis, and Clarias species the LC50 values were 0.42, 0.32 and 0.64?mg?L?1, respectively for over a 2–3 day period. For a three-time influx period of propoxur the LC50 for Chrysicthys, Oreochromis, and Clarias, were 22.0, 30.40, and 45.04 (all in mg?L?1), respectively. The results obtained indicated that the pesticides had adverse effects on the general growth and reproduction of fishes. Gonadosomatic indices also showed that the pesticides affected the development of the body, the gonads, and their reproduction.  相似文献   
257.
The Chinese leadership in recent years has clearly indicated that priority will be given to the development of the western provinces. In view of its under-developed economy, the relative poor education of the population and the extensive mode of development, environmental pollution and ecological damage in western China are more serious than in the east. In China's industrialization process in the modern era, the blind imitation of the initial stage of industrialization in the advanced countries and the total rejection of traditional Chinese cultural values have been particularly striking. Hence, the western provinces should adopt a mode of sustainable development based on establishment of an ecological culture. Environmentalists in China would like to concentrate on reforming the modes of production and the people's lifestyles through changing their views and values. They perceive this as the major commitment for building an ecological culture and promoting sustainable development. But large-scale and concentrated damage to the environment are very often the result of neglect and mistakes by government authorities and corporations. Pessimists worry that this millennium will signal the terminal stage for natural values; but there may be an alternative: a millennium of coordinated development, respecting the environment and based on adoption of a new ecological culture.  相似文献   
258.
ABSTRACT

This study investigated whether endorsement of personal values is associated with willingness to pay more for mobile phones with an environmental or social sustainability label. Participants were students in Sweden, Norway and Germany. A self-report inventory was used to measure willingness to pay and the importance attached to values of Schwartz’s circular model. In Sweden and Norway, participants were willing to pay, on average, 18% extra for a mobile phone with labels for environmental or social sustainability. In Germany, the corresponding share was 12%. To strive for self-enhancement values, that is, social status and prestige, as well as control and dominance over people and resources, was associated with a lower willingness to pay for mobile phones with labels for environmental or social sustainability in all three countries. Furthermore, women were willing to pay more than men for mobile phones with both kinds of sustainability labels. In Sweden and Norway, participants were, on average, willing to pay more for a mobile phone with a label for social sustainability compared to a mobile phone with a label for environmental sustainability.  相似文献   
259.
We investigated the effect of financial incentives on performance in a professional organization. Whereas agency theory treats tangible rewards such as money as a potentially powerful motivator for improving performance, the professional control perspective posits that the motivational effects of financial incentives will depend on the intended recipients attitudes toward the incentives relative to their professional values. The study setting was a large network of physician practices that adopted a financial incentive program to improve physician performance in the management of diabetic patients. Consistent with agency theory, performance did improve following the introduction of the incentive. However, consistent with the professional control perspective, physicians' psychologically based attitudes toward the incentive program regarding its impact on their own work autonomy and the importance of the performance goals moderated the effect of the incentive on performance. Study findings indicate that agency theory and professional control are complementary theoretical perspectives for understanding how professionals will respond to the imposition of performance‐related financial incentives. In terms of practice, pay‐for‐performance programs aimed at professional organizations should be designed to take into account the values and goals of an organization's professionals to maximize the effect of financial incentives on performance. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
260.
基于均一化降水资料的中国极端降水特征分析   总被引:5,自引:1,他引:4  
论文利用中国1961—2012年602个测站均一化的日降水资料,基于世界气象组织定义的11个极端降水指数,分析了近52 a中国极端降水事件的时空分布特征。结果表明:年极端降水指数长期变化趋势表明,大部分极端降水指数在我国西北和长江中下游地区(除CDD)以及东南沿海和华南大部分地区均呈现增加趋势,而在华北地区为减少趋势。极端降水指数随时间的变化表明,各指数具有明显的年际和年代际变化,从2000年开始大部分指数表现为不同程度的增加趋势,即极端降水事件从2000年开始偏多。  相似文献   
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