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1.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   

2.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   

3.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   

4.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   

5.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yang Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   

6.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published.  相似文献   

7.
Studying the structure of social interactions is fundamental in behavioral ecology as social behavior often influences fitness and thus natural selection. However, social structure is often complex, and determining the most appropriate measures of variation in social behavior among individuals can be difficult. Social network analysis generates numerous, but often correlated, measures of individual connectedness derived from a network of interactions. We used measures of individual connectedness in networks of affiliative and agonistic interactions in yellow-bellied marmots, Marmota flaviventris, to first determine how variance was structured among network measures. Principal component analysis reduced our set of network measures to four “social attributes” (unweighted connectedness, affiliation strength, victimization, and bullying), which revealed differences between patterns of affiliative and agonistic interactions. We then used these extracted social attributes to examine the relationship between an individual’s social attributes and several performance measures: annual reproductive success, parasite infection, and basal stress. In male marmots, bullying was positively associated with annual reproductive success, while in females, affiliation strength was negatively associated with annual reproductive success. No other social attributes were significantly associated with any performance measures. Our study highlights the utility of considering multiple dimensions when measuring the structure and functional consequences of social behavior.  相似文献   

8.
张青  史全良 《生态环境》2010,19(12):2850-2856
采用形态鉴定及基于ITS及rbcL序列构建ML系统发育树对采自云南省姚安县及南华县的10种叶状地衣中分离纯化培养的共生藻进行分析研究。鉴定结果表明5个编号分别为Z1、Z4、Z5、Z6、Z9的树生地衣共生藻样品鉴定为念珠藻目(Nostocales)念珠藻科(Nostocaceae)念珠藻属(Nostoc);2个土生地衣共生藻样品Z2、Z10鉴定为四孢藻目(Tetrasporales)胶球藻科(Coccomyxaceae)胶球藻属(Coccomyxa);3个石生地衣分离藻样品Z3、Z7、Z8鉴定为绿球藻目(Chlorococcales)栅藻科(Scenedesmaceae)链带藻属(Desmodesmus)。另外从地衣采集地及分子系统分析结果可以看出,尽管Z1、Z5、Z9分别是从采自不同区域(姚安县及南华县)的地衣中分离纯化的,但亲缘关系最近;同样Z4、Z6亲缘关系最近;Z2、Z10亲缘关系最近,Z7、Z8亲缘关系最近。所以地衣共生菌与共生藻的共生关系与其生存的地理区域关系不大,但却和其生长基质有明显的相关性。  相似文献   

9.
Abstract: We examined the relationship between authorship and the use of biological information in recovery plans under the U.S. Endangered Species Act. Approximately one-third of recovery plans were written solely by federal government employees, and one-third of plans included authors with university affiliations. The number of plans written strictly by federal staff increased significantly over time, whereas the percentage of plans that included authors with university affiliation remained unchanged. We tested three hypotheses posed by Clark et al. (1994) regarding authorship and endangered species recovery and found that (1) groups of authors from diverse affiliations are likely to strengthen the recovery planning process, (2) recovery plans lacking nonfederal participation suffer from inadequate attention to species biology, and (3) academic affiliation is strongly associated with the use of focal-species biology in recovery plans. Our results suggest that modifying the choice of participants in the recovery planning process may increase the use of biological information in recovery measures recommended in recovery plans and thus influence the eventual success of recovery efforts.  相似文献   

10.
提高资源环境绩效是我国实现生态现代化及绿色发展的重要途径。利用环境质量指数(EQI)和资源环境绩效指数(REPI)对我国中部生态环境脆弱区的山西省资源环境绩效进行了系统分析,结果表明:在全国资源环境综合绩效指数年增幅为7.1%的背景下,山西在全国的排名从2000年的24位上升为2007年的15位。但山西仍然为我国资源环境绩效水平最为落后的地区之一。山西建设用地绩效、COD排放绩效、SO2排放绩效和用水绩效逐步上升,工业固体废弃物排放绩效和能源绩效呈现不稳定的变动态势。SO2排放绩效指数呈平稳后上升接着下降的偏"S"型曲线。COD总体绩效指数呈现平稳态势,基本保持88.1的均值水平,绩效指数高于2000—2007年西部平均水平和2000—2003年中部平均水平,但远低于东部和全国平均水平。资源环境指数与经济发展水平和发展阶段密切相关,山西须采用综合配套措施,缩短目前能源和资源密集型的发展阶段和改变其路径依赖,提升山西在我国中部地区的综合竞争力,改进生态效率,进而实现绿色发展。  相似文献   

11.
Previous experimental work suggests flexibility in women’s mate preferences that appears to reflect the advantages of choosing healthy mates under conditions of pathogen threat and of choosing prosocial mates under conditions of resource scarcity. Following this work, we used an established priming paradigm to examine the effects of priming women’s concerns about pathogen threat versus resource scarcity on their judgments of men’s facial attractiveness and dominance. We found that women reported stronger attraction to masculine men when their concerns about pathogens were activated than when their concerns about resource scarcity were activated. In contrast, we found that women were more likely to ascribe high dominance to masculine men when their concerns about resource scarcity were activated than when their concerns about pathogens were activated. This latter result may reflect the greater importance of identifying men who pose a substantial threat to women’s resources and personal safety when resources are scarce and violence towards women is particularly common. Together, these findings suggest a double dissociation between the effects of pathogen threat and resource scarcity on women’s perceptions of the attractiveness and dominance of masculine men, potentially revealing considerably greater specialization (i.e., context specificity) in the effects of environmental threats on women’s perceptions of men than was apparent in previous research.  相似文献   

12.
As central-place foragers, pelagic seabirds are constrained by spatiotemporal heterogeneity to find productive marine areas and compete for prey. We analysed 97 foraging trips to study the movement and oceanographic characteristics of foraging habitats of two different—yet closely related—species of shearwaters (Scopoli’s shearwater Calonectris diomedea and Cory’s shearwater C. borealis) breeding in sympatry in the Mediterranean. We combined various methodological approaches (GPS-tracking, species distribution modelling and stable isotope analysis) to explore the foraging strategies of these two species. Isotopic results suggested that trophic habits of both shearwater species were similar, mainly based on pelagic fish consumption. Foraging areas of both species were characterized by shallow waters near the colony. Both shearwater species exploited persistent productive marine areas. The foraging areas of the two species broadly overlapped during the incubation period, but during chick-rearing period, Scopoli’s shearwaters apparently foraged in different areas than Cory’s shearwaters.  相似文献   

13.
Effective management and conservation of species, subspecies, or ecotypes require an understanding of how populations are structured in space. We used satellite-tracking locations and hierarchical and fuzzy clustering to quantify subpopulations within the behaviorally different barren-ground caribou (Rangifer tarandus groenlandicus), Dolphin and Union island caribou (R. t. groenlandicus x pearyi), and boreal (R. t. caribou) caribou ecotypes in the Northwest Territories and Nunavut, Canada. Using a novel approach, we verified that the previously recognized Cape Bathurst, Bluenose-West, Bluenose-East, Bathurst, Beverly, Qamanirjuaq, and Lorillard barren-ground subpopulations were robust and that the Queen Maude Gulf and Wager Bay barren-ground subpopulations were organized as individuals. Dolphin and Union island and boreal caribou formed one and two distinct subpopulation, respectively, and were organized as individuals. Robust subpopulations were structured by strong annual spatial affiliation among females; subpopulations organized as individuals were structured by migratory connectivity, barriers to movement, and/or habitat discontinuity. One barren-ground subpopulation used two calving grounds, and one calving ground was used by two barren-ground subpopulations, indicating that these caribou cannot be reliably assigned to subpopulations solely by calving-ground use. They should be classified by annual spatial affiliation among females. Annual-range size and path lengths varied significantly among ecotypes, including mountain woodland caribou (R. t. caribou), and reflected behavioral differences. An east-west cline in annual-range sizes and path lengths among migratory barren-ground subpopulations likely reflected differences in subpopulation size and habitat conditions and further supported the subpopulation structure identified.  相似文献   

14.
Forestry development in China has undergone a series of reforms over the past six decades. This article examines temporal changes in forest resources and policies, the current status of forestry, and future challenges toward sustainable forest management in China. Excessive logging in the 1950s to 1980s badly damaged the nation’s forests, but the adoption of enlightened forest policies in the late 1990s has led to increases in China’s total forest area and growing stock. Forest degradation was ecologically and economically costly, and rehabilitation processes have become increasingly more expensive. The low quality and young age of forest resources, loss of natural forests, and more difficulties in afforestation and reforestation pose severe challenges for China’s sustainable forestry. It is critically important for China to enhance forest productivity through intensive management, strengthen enforcement, and educational programs for protecting and restoring natural forests, narrow the gap between domestic timber supply and rapidly expanding consumption, improve coordinating networks for management, finance, and technology transfer, and accelerate efforts to clarify and stabilize tenure arrangements for non-state forests. China’s experience and lessons in forestry may be helpful for other developing countries that are seeking to achieve the goal of sustainable forest management.  相似文献   

15.
城市绿地滞尘作用机理和规律的研究进展   总被引:7,自引:0,他引:7  
城市绿地的滞尘作用是城市绿地重要的生态功能之一。综述了城市绿地的滞尘机理、变化规律。城市绿地的滞尘机理主要分为3种方式:滞留、附着和粘附;城市绿地滞尘能力与滞尘时间、城市环境、植物种、植物群落结构等因素存在密切的联系。不同植物滞尘能力的差异很大,总体规律表现为乔木植物〉灌木植物〉草本植物;但就单位叶面积来说,滞尘能力均以草本植物〉灌木植物〉乔木植物〉藤本植物;主要原因是垂直高度不同,灌草能有效截留地面的扬尘(城市中灰尘的主要来源)。研究表明,同种类植物种在封闭式环境条件下叶片滞尘量明显低于开敞式环境条件下的滞尘量,因此,在城市不同环境中的植物滞尘能力表现为工业区〉商业交通区〉居住区〉清洁区。随着季节和滞尘时间的变化,每种植物都存在一个滞尘限度,如果无雨水或人为干扰,最终达到一个动态平衡。从城市绿地群落的垂直结构看,乔—灌—草型的绿地具有相对较好的滞尘作用,是目前较为理想的绿地类型;另外,在城市绿地面积明显不足的情况下,以藤本植物为主的垂直绿化将成为城市绿化发展的新方向。同时,在城市绿地滞尘机理、规律以及植物滞尘能力评价等方面仍需要进一步深入研究。  相似文献   

16.
In this study, we determined mercury and selenium levels in abandoned unhatched eggs of the yellow-legged gull (Larus michahellis) and Audouin’s gull (Larus audouinii) collected during 2004–2005 from the Tuscan archipelago and Sardinia (Italy). The different feeding habits of the two species probably determine the different uptakes of trace elements, as the study shows highly significant differences for selenium and mercury levels as well as shell thickness and Hg:Se molar ratio values. Audouin’s gulls nesting on the coasts of the Tuscan archipelago showed significantly higher selenium levels than did gulls from colonies from the islands around Sardinia. Comparisons with a similar investigation previously conducted in the same area suggested that mercury and selenium concentrations, although in line with reports in the literature, were significantly lower than levels encountered in gulls in the early 1980s. Mercury (mg/kg d.w.) dropped from 8.631 to 5.030 in Audouin’s gulls and from 2.509 to 0.828 in yellow-legged gulls. The regional decline in mercury levels following reduced use of the metal in industry and the probable food depletion effects linked to the overfishing of fish prey of these two gull species are discussed as hypotheses that could explain the decrease in mercury levels found in eggs.  相似文献   

17.
Sooty mangabeys are terrestrial monkeys exhibiting female philopatry and male dispersal. Studies in captivity as well as in the wild have found that adult females form linear dominance hierarchies. However, while captive studies found no evidence for a matrilineal social system, a previous study in Taï National Park, Ivory Coast, suggested that relatedness could influence both dominance rank and affiliation pattern among adult females. Here I test whether the dominance rank, coalitionary behavior, and affiliative behavior of juveniles in a group of free-ranging mangabeys in the Taï National Park are in accordance with a matrilineal, individual, or age-related dominance system. I found that juvenile females' dominance ranks remained stable over time and were highly correlated with the dominance ranks of their mothers, whereas juvenile males' dominance ranks were initially correlated with the ranks of their mothers, but showed greater instability with increasing age. Moreover, coalitions occurred mainly between juveniles and animals that were close in rank, including their mothers and siblings. Finally, juvenile females associated and groomed preferentially with close-ranking juvenile and adult females. Juvenile males showed similar preferences in affiliation with adult females, but when associating with juvenile males, they preferred peers. The observed social behavior of free-ranging juvenile sooty mangabeys resembled the social behavior described for juveniles of many matrilineal primate species.  相似文献   

18.
方恺 《生态环境》2014,(11):1868-1875
足迹家族和行星边界都是国际可持续发展研究领域新近出现的热点概念。系统回顾了足迹家族和行星边界的概念缘起,首次提出了基于足迹家族和行星边界的环境可持续性概念及其评价框架。其中,足迹家族定义为:人类在自然资源消费和废弃物排放过程中占用的地球生态系统的再生和消纳能力;行星边界定义为:可供人类安全占用的地球生态系统的最大再生和消纳能力。由此,将环境可持续性定量描述为人类环境足迹小于或等于对应行星边界的情形,反之则为环境不可持续性。分析了该环境可持续性概念的6项基本特征:系统性、选择性、交互性、不确定性、尺度依赖性、赤字可权衡性。在此基础上,以全球30个主要国家为例,对提出的足迹家族-行星边界整合框架进行了实证应用。从与人类社会关系重大的环境问题入手,对各国在气候变化(碳排放)、水资源利用和土地利用3方面的环境可持续性进行了多维测度。结果显示:22国的碳排放呈现不可持续性,人均碳赤字最高为美国的26.1 t·a-1(以CO2当量计);17国的水资源利用呈现不可持续性,人均水赤字最高为西班牙的1497.8 m3·a-1;15国的土地利用呈现不可持续性,人均土地赤字最高为荷兰的2.3 hm2·a-1。研究表明,碳排放的可持续性与社会经济发展水平关系密切,发达国家对气候变化的贡献明显大于发展中国家;水资源利用和土地利用的可持续性则更多地受各国人均资源禀赋制约。本研究对科学量化和比较不同国家的环境可持续性具有参考价值,该评价方法也适用于其他环境问题或国家以下尺度的核算分析。  相似文献   

19.
One central aspect of the environmental management system for universities developed in Osnabrück is the environmental audit of universities, realized by an ecobalance. This article deals with modelling the material and energy flows caused by the University’s commuters (staff and students), and by the business trips of employees, using the software Umberto®. The result is the University’s traffic balance. 10,000 MWh of energy are consumed yearly by the University’s traffic. 94% of the consumption is caused by commuters (1,300 employees and 11,500 students) and only 6% by business trips. Compared with the whole energy consumption of the University, the traffic’s share is 32% and therefore lies between the electricity’s share (25%) and that of heat (43%). Similarly related are the CO2 emissions, caused by traffic (3,160 tons per anno). Compared with the whole CO2 emissions of the University the traffic’s share is 31%, thus putting it between the heat’s share (27%) and that of electricity (42%). Although the average weekly distance the University’s commuters drive (79 km/student and 84 km/employer) is at the bottom of the range for other comparable universities, a transportation demand management for a further reduction of the traffic-caused CO2 emissions should be implemented.  相似文献   

20.
随着工业的迅速发展,迄今为止,已有大约10万种化学物进入人们的日常生活.人们在生产和生活中接触的许多种环境化学物都会影响人类的生殖功能,使人类的生育能力特别是精子的质量和数量发生显著改变.环境化学物所造成的生殖损伤日益受到人们的重视,检测方法和检测技术日益成熟和完善.但大多数环境化学物对生殖的损害目前尚未得到全面地研究和认识,某些毒物的生殖毒性也需要重新认识与评价,生殖毒理学的研究任务迫切而艰巨.动物实验是生殖毒性评价中最主要的方法.在总结近年来国内外相关研究基础上综述了环境化学物动物实验中雄(男)性生殖损伤评价指标及检测技术,以期对环境化学物生殖毒性评价提供借鉴和参考.  相似文献   

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