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211.
Jimnez Begoa Merino Rubn Abad Esteban Rivera Josep Olie Kees 《Environmental science and pollution research international》2007,14(1):61-68
Background Species that are at high levels of the food web have often been used as bioindicators to evaluate the presence of persistent
contaminants in ecosystems. Most of these species are long-lived, so pollutant burdens may be integrated in some complex way
over time. This makes them particularly sensitive to deleterious effects of Persistent Organic Pollutants (POPs). Birds have
been suggested as useful organisms for monitoring pollutant levels. Traditionally such studies have been carried out with
raptors such as osprey (Pandion haliaetus), peregrine falcon (Falco peregrinus), bald eagle (Haliaetus leucocephalus), etc. In this paper we present the results of a monitoring study conducted on two raptor species, osprey (Pandion haliaetus) and red kite (Milvus milvus), inhabiting a Mediterranean island (Menorca, Spain). These two species have different feeding habits; ospreys prey on fish
and red kites feed on terrestrial species. This study constitutes a good opportunity to investigate if differences in feeding
habits (aquatic vs. terrestrial) influences the contaminants pattern in two species inhabiting the same area.
Methods The study was conducted in a non-destructive way, using only failed eggs, to avoid the damage of the population stability.
Eggs were collected during the period 1994–2000. The contaminants examined were dichlorodiphenyltrichloroethanes (DDTs, including
DDT and its main metabolite, DDE), polychlorinated biphenyls (PCBs), including ortho PCBs (PCBs with at least one Chlorine
atom in the ortho position): #28, 52, 95, 101, 123+149, 118, 114, 153, 132+105, 138, 167, 156, 157, 180, 170, 189, 194; and
non ortho PCBs (PCBs with no Chlorine atom in the ortho position): #77, 126, 169 and all the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) with Chlorine atoms at the 2,3,7 and 8 position (2,3,7,8-substituted
PCDDs and PCDFs). The analysis of organochlorine compounds was performed using a sample treatment based on a Solid Phase Matrix
Dispersion procedure. Ortho PCBs and DDTs were determined by HRGC-μECD; non ortho PCBs and PCDD/Fs were determined by HRGC-HRMS.
Results and Discussion The sum of the ortho PCB congeners analysed ranged from 0.94 to 15.03 μg/g wet weight (ww) for ospreys and from 1.0 to 11.2
μg/g ww for red kites. In both species, PCB congeners #153, #138 and #180 accounted about 75% to total ortho PCB concentrations.
Regarding non ortho PCBs, for ospreys, concentrations ranged from 0.16 to 1.39 ng/g wet weight (ww) and for red kites from
0.12 to 0.51 ng/g ww, being congener #126 the most abundant. Concerning DDTs, concentration for ospreys ranged from 0.07 to
1.03 μg/g ww; and for red kites ranged from 0.90 to 2.10 μg/g ww, representing DDE more than 95% of the total DDTs, which
proves a past use of DDT in the study area. Differences in contaminant levels between species are probably associated to feeding
habits. The fish-eating species presents the highest PCB levels, whereas the terrestrial species exhibits the highest DDT
levels. PCDD/Fs in ospreys were in the range 2.6–14.2 pg/g ww, while in red kites the range was slightly wider (22.2–43.2
pg/g ww), being PCDDs the major contributors in black kites. Ospreys had PCDDs similar to PCDF concentrations. PCDD/F profiles
were mostly influenced by OCDD in both species. Non ortho PCBs were the major contributors to calculated Toxic Equivalent
Quantity (TEQs) in both species.
Conclusion In both species studied, ortho-PCBs could represent a problem of concern since 57% of the eggs exhibited levels higher than
4 μg/g ww, reported as the level that could cause reduced hatchability, embryo mortality, and deformities in birds.
Recommendations and Outlook Results found in this study suggest that a more detailed study to clear up possible deleterious effects of PCBs on the bird
populations studied here should be done.
Section Editor: Prof. Dr. Paola Gramatica (paola.gramatica@uninsubria.it) 相似文献
212.
--Hainan
Island, located at the southern end of China, hasless than 0.4% of land area but contains
13% of plant and animalspecies in China. During the last four decades many primary
forestshave been converted to shrub land, grassland, and tree planation(e.g., eucalyptus
forest). As a result, area of primary tropicalforest has been reduced from 25.8% in the
1950s to 4% in the 1990s.To assess impacts of land conversion on plant and bird
speciesdiversity, a series of samples in primary forest and four types ofconverted lands
were took. The land conversion had tremendouslyreduced both plant and bird species
diversity. Specifically, plantspecies richness per site was 83.7 in primary forest, 28.3
in shrubland, 12.5 in grassland, 14.4 in eucalyptus forest, and 21.4 inAcacia forest. Bird
species richness showed a similar trend 22.0in primary forest, 14.5 in shrub land, 2.5 in
grassland, 4.9 ineucalyptus forest, and 9.0 in Acacia forest. The Shannon speciesdiversity
indices for plants in the five types of land cover were3.69, 1.99, 0.97, 1.47 and 2.07,
respectively. Similarly, the Shannon indices for bird species diversity were the highest
in primary forest, and lowest in grassland, and intermediate in shrubland and eucalyptus
forest. 相似文献
213.
从台湾岛基本地质特征出发,通过与大陆东南沿海及邻近地区之间的地质对比,提出关于台湾岛成因的新假说,即台湾岛是在晚中生代随着东南大陆的离散而逐渐分离出去的一个陆块,并经历逆时针旋转,于中新世以后在福建沿海与大陆碰撞拼贴. 相似文献
214.
The impacts of economic forest on global environmental change(GEC) are one of the hot issues in environmental study. Based on the 3-year observation data and 40-year climate data, GEC and analysis of the hydrological dynamic characteristics of rubber plantations and estimate of the water balance in the rubber plantations in Hainan Island were made. The results showed that the rainfall intercepted by thecanopy of the plantations accounted for 11.4-5 % of the annual rainfall, the total runoff for 23.71%, the total evaporation and transpiration for 63.24%, the soil moisture storage for 1.6%. Analysis of the 40year rainfall data in the 19 counties of Hainan Island during 1951—1990 showed that the large-scale substitution of the natural vegetation with the rubber plantations had no significant effect on the local rainfall in Hainan Island. The main reasons are (1) 80% of the rainfall in Hainan is brought by typhoons; (2) the proportion of 11.6% rubberplantations in total forest coverage in Hainan is not enough to influence the local rainfall in Hainan Island; and (3) although the rubberplantation is artificial vegetation, it has the similar function to the tropical rain forest. Analysis of the total water resource and I‘otal GDP ofHainan in 1997 showed that the economic benefit resulted from the water resource was 1.0 RMB Yuan/m3 . The value of hydrological of therubber plantation in Hainan was 113.9 million RMB Yuan/a when compared with the tropical rain forest. The paper reaches conclusion that the hydrological eco-service function of rubber plantation has been enhanced after transformed from natural vegetation, which includes the natural service and powerful social service. 相似文献
215.
Impacts of land cover change on plant and bird species diversity in Hainan Island,China 总被引:2,自引:0,他引:2
1IntroductionLandcoverchangehasanincreasingimpactonforestecosystemsworldwide.Thedestructionofnativehabitatsisrecognizedasoneo... 相似文献
216.
217.
人工浮岛在丁香湖水质改善中的应用 总被引:1,自引:0,他引:1
针对丁香湖水体恶化产生蓝藻的问题,在湖中设置人工浮岛对水质进行改善,浮岛植物以凤眼莲为主,辅以美人蕉等搭配.人工浮岛运行后,对水体中TN、TP指标净化效果良好,TN的去除率为48.1%~52.1%,TP的去除率为55.0%~64.4%,而且具有一定的景观效果. 相似文献
218.
文章以厦门岛为例,采用多元回归模拟和空间分析技术相结合的方法,选取了与厦门岛城市餐厨垃圾产量相关的土地利用、GDP、人口等相关社会经济地理因子进行空间化模拟研究。结果表明:(1)所选地理因子均对餐厨垃圾密度空间分布有一定影响,其中商住混合用地、商业服务用地、城镇住宅用地和城中村用地等土地利用类型的面积比例是主要的影响因子。(2)受多种因素共同影响,筼筜湖周边及厦门岛西南等商业繁华的区域餐厨垃圾密度较高,呈现空间集聚效应。(3)模型验证结果较为理想,各街道内餐厨垃圾总量模拟值与统计值比较符合,实现了厦门岛餐厨垃圾总量的降尺度模拟,是研究城市餐厨垃圾分布规律和实现餐厨垃圾产量空间化的一种尝试,以便为城市餐厨垃圾科学管理和决策提供参考,为餐厨垃圾资源化回收利用提供基础空间数据。 相似文献
219.
220.
The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these
plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to
have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study
of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and
bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and
deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only
occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen
vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero
in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single
genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to
expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species. 相似文献