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11.
根据2010年1月31日~2月13日在南极南奥克尼群岛西部水域开展的南极海洋生物资源调查期间收集的数据及卫星获取的水温数据(海水表温和表温距平),对南极磷虾时空分布及其与表温之间的关系进行了分析.结果表明:(1)02:00~18:00为南极磷虾群出现频率较高的时段,随后南极磷虾群出现概率开始下降,至22:00 ~02:...  相似文献   
12.
    
Polycyclic aromatic hydrocarbons (PAHs) investigation in different matrices has been reported largely, whereas reports on snow samples were limited. Snow, as the main matrix in the polar region, has an important study meaning. PAHs in snow samples were analyzed to investigate the distribution and contamination status of them in the Antarctic, as well as to provide some references for global migration of PAHs. Snow samples collected in Fildes Peninsula were enriched and separated by solid-phase membrane disks and eluted by methylene dichloride, then quantified by gas chromatography/mass spectrometry. All types of PAHs were detected except for Benzo(a)pyrene. Principal component analysis method was applied to characterize them. Three factors (Naphthalene, Fluorene and Phenanthrene) accounted for 60.57%, 21.61% and 9.80%, respectively. The results showed that the major PAHs sources maybe the atmospheric transportation, and the combustion of fuel in Fildes Peninsula. The comparison of concentration and types of PAHs between accumulated snow and fresh snow showed that the main compound concentrations in accumulated snow samples were higher than those in fresh ones. The risk assessment indicated that the amount of PAHs in the snow samples would not lead to ecological risk.  相似文献   
13.
姜苏  李院生  潘广文  王越 《环境化学》2012,31(2):249-253
利用一维离子色谱建立了高氯酸盐的在线富集方法,以期为建立定量检测南极雪冰中痕量高氯酸盐的离子色谱-串联质谱法奠定基础.选用高容量、强亲水性的IonPac AS20阴离子交换柱进行分离,以淋洗液自动发生器在线产生的KOH作为淋洗液,等梯度淋洗.考虑到南极雪冰样品量十分有限,选定5 mL为富集体积,对应的富集时间为10 min.高氯酸盐质量浓度在0.5—50 μg·L-1范围内,方法具有良好的线性(相关系数为0.9995),检出限(以S/N=3计)为0.05 μg·L-1.将浓度为0.5 μg·L-1的标准溶液连续11次富集进样,所得峰面积的相对标准偏差(RSD)为4.7%.以人工配制的仅含有高氯酸盐的溶液实施了加标回收实验,回收率在85%—108%之间.  相似文献   
14.
80年代以业南极上空平流层臭氧层不断减少,1998年9月臭氧洞的面积和深度达历史最高记录。平流层臭氧耗损会导致到达在面地的有害紫外线增加,损害人类的健康和破坏地球生态。介绍了了臭氧层损耗的机理、现状、该领域的研究进展和复旦大学的研究结果。  相似文献   
15.
    
Antarctic fur seals (Arctocephalus gazella) were commercially exploited on the subantarctic island of South Georgia for over 100 years and nearly driven to extinction. Since the cessation of harvesting, however, their populations have rebounded, and they are now often considered a nuisance species whose impact on the terrestrial landscape should be mitigated. Any evaluation of their current population requires the context provided by their historic, pre-exploitation abundance, lest ecologists fall prey to shifting baseline syndrome in which their perspective on current abundance is compared only with an altered state resulting from past anthropogenic disturbance. Estimating pre-exploitation abundance is critical to defining species recovery and setting recovery targets, both of which are needed for the International Union for the Conservation of Nature's recent efforts to develop a green list of recovering species. To address this issue, we reconstructed the South Georgia fur seal harvest from 1786 to 1908 from ship logbooks and other historical records and interpolated missing harvest data as necessary with a generalized linear model fit to the historical record. Using an approximate Bayesian computation framework, harvest data, and a stochastic age-structured population model, we estimated the pre-exploitation abundance of Antarctic fur seals on South Georgia was 2.5 million females (95% CI 1.5–3.5 million). This estimate is similar to recent abundance estimates, and suggests current populations, and the ecological consequences of so many fur seals on the island, may be similar to conditions prior to human harvest. Although the historic archive on the fur sealing era is unavoidably patchy, the use of archival records is essential for reconstructing the past and, correspondingly, to understanding the present. Article impact statement: Defining species recovery requires an understanding of baseline population state, which can be estimated through statistical methods.  相似文献   
16.
Summary The fitness of a parent in an altricial bird species is likely to be a function of the proportion of resources allocated to offspring production in relation to the amount spent on its own survival. Here we report an experiment on the Antarctic petrel in which we manipulated the costs of rearing an offspring by placing small lead loads on the legs of one parent. The bird could then either decrease its own body reserves or reduce the food load to the chick. The manipulated birds decreased their food load and increased the feeding interval, compared with unmanipulated birds. Consequently, the rate of chick loss increased. No significant difference was found between the body weights of experimental and control birds during the experiment.Publication no. 113 from the Norwegian Antarctic Research Expedition (NARE) 1989/90 Correspondence to: B.-E. Sæther  相似文献   
17.
Two independent digestion procedures for Antarctic krill samples were compared. Dry ashing (DA) and microwave (MW) acid‐assisted digestion were tested for decomposing the samples to determine essential (Cu, Fe, Cr) and toxic elements (Cd, Pb) by graphite furnace‐atomic absorption spectrometry (GF‐AAS). A mixture of HNO3 and H2O2 as digesting agent was used in the microwave procedure. For the dry ashing digestion, the organic matter was oxidated at 480°C in an open system. Both digestion methods were compared in terms of accuracy and applied to the analysis of a certified reference material: MURST‐ISS‐A2 (Antarctic krill).

The detection limits for the five elements analysed ranged from 3 to 150 ng g‐1. Both digestion procedures are suitable for the decomposition of krill samples. However, dry ashing is not recommended to determine Pb and Cd because losses can occur.  相似文献   
18.
    
Antarctica terrestrial ecosystems are facing the most threats from global climate change, which is altering plant composition greatly. These transformations may cause major reshuffling of soil community composition, including functional traits and diversity, and therefore affect ecosystem processes in Antarctica. We used high-throughput sequencing analysis to investigate soil nematodes under 3 dominant plant functional groups (lichens, mosses, and vascular plants) and bare ground in the Antarctic region. We calculated functional diversity of nematodes based on their diet, life histories, and body mass with kernel density n-dimensional hypervolumes. We also calculated taxonomic and functional beta diversity of the nematode communities based on Jaccard dissimilarity. The presence of plants had no significant effect on the taxonomic richness of nematodes but significantly increased nematode functional richness. The presence of plants also significantly decreased taxonomic beta diversity (homogenization). Only mosses and vascular plants decreased nematode functional beta diversity, which was mostly due to a decreased effect of the richness difference component. The presence of plants also increased the effect of deterministic processes potentially because environmental filtering created conditions favorable to nematodes at low trophic levels with short life histories and small body size. Increasing plant cover in the Antarctic due to climate change may lead to increased diversity of nematode species that can use the scarce resources and nematode taxonomic and functional homogenization. In a future under climate change, community restructuring in the region is possible.  相似文献   
19.
南极内陆地区以其特殊的地理位置和特有的生态环境在研究全球变化尤其是气候变化中发挥不可替代的作用.随着越来越多的科考站在南极内陆地区建立,人类活动对南极环境的不利影响的程度和性质正在发生范围的扩散和层次的转移.本研究以中国昆仑站为例,依据不同类型活动的发生概率、范围、持续时间,严重程度的不同,对在南极内陆地区建立科考站所产生的环境影响进行了综合分析,结果表明,科考站的建设和运行对南极内陆环境及其附属的生态系统带来了不可避免的负效应,提出相关减缓措施以期尽可能减缓不良的环境影响,这不仅为日后南极科考活动提供规范化指导,还为南极内陆地区环境污染的控制及管理和可持续发展提供参考.  相似文献   
20.
作者根据参加中国第5次南极考察的经历,从地理环境尤其是气候和资源对航空、航海、科考的影响,讨论了乔治王岛地区在科学研究上的战略意义。根据对地质基础、矿产、火山活动以及冰川浸蚀历史和地貌现象的讨论,指出该区是研究古气候、古环境、大陆漂移和冰川冰缘地貌的极好场所;并指出该区种类全、数量多且具有南极特征的动植物和奇特的食物链关系是其成为重要生物资源区和受条约保护的特别科学兴趣场所的主要原因。  相似文献   
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