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31.
Klopchin JL Stewart JR Webster LF Sandifer PA 《Environmental monitoring and assessment》2008,137(1-3):301-313
Morgan Island, located within the ACE Basin National Estuarine Research Reserve in South Carolina, is home to the only free-ranging
colony of rhesus monkeys (Macca mulatta) in the continental United States. The purpose of this study was to assess environmental impacts of the monkey colony on
water quality in adjacent tidal creeks and on island vegetation. Three tidal creeks were sampled: Morgan Creek, adjacent to
the monkey colony; Back Creek, on Morgan Island not adjacent to the colony; and Rock Creek, on a nearby island unoccupied
by monkeys. Temperature, salinity, pH, dissolved oxygen, nutrients and fecal coliform bacteria were measured six times at
three sites in each of these creeks, and vegetation change analysis was conducted in a geographic information system using
satellite imagery. Results showed elevated fecal coliform concentrations in the Morgan Creek site immediately adjacent to
the colony, though no samples exceeded the standard set for recreational water use. Ribotyping reconnaissance matched four
Escherichia coli isolates from Morgan and Back Creeks to the monkeys, identifying the colony as one source of fecal coliform bacteria, though
relative source loadings could not be quantified. Significant differences were not observed between ammonia or orthophosphate
levels in Morgan Creek relative to the other creeks tested; and vegetation change analysis showed a 35% increase in canopy
cover between 1979 and 1999. Overall, these results suggest that the rhesus colony’s environmental impacts are localized and
minimal. Results from this study provide baseline data on Morgan Island and may be useful in management decisions regarding
the future of the monkey colony. 相似文献
32.
为更好地推动崇明低碳生态岛的建设,在应用以自下而上的部门法为基础的区域范围温室气体排放评估核算方法,全面核算崇明岛能源消费及温室气体排放现状的基础上,应用LEAP模型,通过情景分析预测崇明岛中长期能源消费需求以及温室气体排放水平,并进一步应用对数平均指数法(LMDI)对影响崇明岛未来温室气体排放的主要因素进行了定量分析。研究表明:参考情景下,崇明岛能源消费总量从2010年的101万吨标煤增加到2050年的533万吨标煤,净碳足迹从2010年的238万吨CO2e增加到2050年的579万吨CO2e。崇明岛能源消费需求和碳排放增加的主要驱动因素是未来的经济发展、人口增长和生活水平的提高,但是通过一系列的优化,尤其是能源结构的变化和能耗强度的下降,减排情景下,崇明岛能源消费总量有可能在2039年左右达到峰值,并有望在2050年左右实现"零碳岛"的长期发展目标。结合定量分析的结论,进一步提出了实现崇明岛低碳发展中长期目标的可能性和重点发展领域。 相似文献
33.
Chinstrap and gentoo penguins are endemic species that live year round south of the Antarctic Convergence. South polar skua is a migratory seabird that can be observed in Antarctica during the breeding season (i.e., austral summer). This study compares concentration and pattern of polybrominated diphenyl ethers (PBDEs) in eggs of seabirds breeding at King George Island, Antarctic Peninsula. PBDEs in south polar skua eggs are approximately 20 times higher than in penguin eggs suggesting that skuas are more exposed to contaminants during the non-breeding season when they migrate to waters of the northern hemisphere. The pattern of PBDE congeners also differs between south polar skua and penguin eggs. The latter exhibited a pattern similar to that found in the local biota. In contrast, the congener pattern in south polar skua eggs suggests that birds breeding at King George Island may winter in the northwestern Pacific Ocean. 相似文献
34.
C. C. Li 《Chemistry and Ecology》1996,12(1):57-66
Water quality was monitored for 12 months in Lake Tai and Lake Zon on Kinmen Island, Taiwan, and physico-chemical conditions were analyzed. No vertical temperature stratification was observed in these shallow lakes. pH is neutral to alkaline and associated with vigorous algal growth. Nitrogen levels are high and present in various forms due to progressive nitrification. Green and blue-green algae play an important part in the process of nitrification.
Assessment of lake eutrophication was made by the use of the N:P ratio, the Trophic State Index (TSI) and the US EPA Eutrophic Screening Model. the result of these calculations indicates eutrophic conditions in both lakes. It is advised that lake restoration be initiated and available techniques are listed. 相似文献
Assessment of lake eutrophication was made by the use of the N:P ratio, the Trophic State Index (TSI) and the US EPA Eutrophic Screening Model. the result of these calculations indicates eutrophic conditions in both lakes. It is advised that lake restoration be initiated and available techniques are listed. 相似文献
35.
雷州半岛与海南岛砖红壤养分比较研究罗凯(广东省徐闻县农村工作委员会,徐闻524100)ComparisonofNutrientsContentofLatosolsinLeizhouPeninsulaandHainanIsland¥LuoKai(Rur... 相似文献
36.
Forty-six trace elements in coastal Casuarina equisetifolia plant–soil systems at nine sampling sites on Hainan Island were analyzed using ICP-MS. The relationships among the trace elements of the same group or the same periodicity of the Periodic Table in the plants and soils were complex and no consistent patterns were found. More combinations of elements occurred with high positive correlation coefficients within the same periodicity than within the same group of the Periodic Table, and there were more high positive correlations in soils than in plants. However, there were many element combinations in Block d (transition elements) with high positive correlation coefficients in plants. Markedly high positive correlation coefficients between individual rare earth elements and Y and among Zr, Nb, Cd existed in both plants and soils. The dendrograms obtained by cluster analysis show that rare earth elements had very similar occurrence and distribution in both soils and plants. Thus, they behaved as a coherent group of elements both geochemically and biogeochemically. The transition elements were more coherent in plants than in soils. 相似文献
37.
38.
Bats produce echolocation signals that reflect the sensory tasks they perform. In open air or over water, bats encounter few
or no background echoes (clutter). Echolocation of such bats is the primary cue for prey perception and varies with the stage
of approach to prey, typically comprising search, approach, and terminal group calls. In contrast, bats that glean stationary
food from rough surfaces emit more uniform calls without a distinct terminal group. They use echolocation primarily for orientation
in space and mostly need additional sensory cues for finding food because clutter echoes overlap strongly with food echoes.
Macrophyllum macrophyllum is the only Neotropical leaf-nosed bat (Phyllostomidae) that hunts in clutter-poor habitat over water. As such, we hypothesized
that, unlike all other members of its family, but similar to other trawling and aerial insectivorous bats, M. macrophyllum can hunt successfully by using only echolocation for prey perception. In controlled behavioral experiments on Barro Colorado
Island, Panamá, we confirmed that echolocation alone is sufficient for finding prey in M. macrophyllum. Furthermore, we showed that pattern and structure of echolocation signals in M. macrophyllum are more similar to aerial and other trawling insectivorous bats than to close phylogenetic relatives. Particularly unique
among phyllostomid bats, we found distinct search, approach, and terminal group calls in foraging M. macrophyllum. Call structure, however, consisting of short, multiharmonic, and steep frequency-modulated signals, closely resembled those
of other phyllostomid bats. Thus, echolocation behavior in M. macrophyllum is shaped by ecological niche as well as by phylogeny. 相似文献
39.
崇明岛公路两侧蔬菜地土壤和蔬菜重金属污染研究 总被引:11,自引:1,他引:11
为了研究崇明岛公路两侧土壤和蔬菜重金属污染状况,采集陈海、北沿公路两侧蔬菜地土壤、蔬菜和路面灰尘样品,测定重金属Pb、Cd、Cu、Zn含量.结果表明,以上海市土壤环境背景值上限值为评价标准,所有土壤样品Pb、Cd、Cu和Zn的超标率分别为10.1%、25.4%、6.5%和8.7%;以HJ 332-2006 食用农产品产地环境质量评价标准中蔬菜地土壤环境质量评价指标限值(pH值6.5~7.5)为标准,Cd超标率在21.0%,仅有不到3%样品Pb含量超标,而没有样品Cu、Zn含量超标.以国家食品卫生标准中规定的重金属限量为标准,路侧蔬菜样品Pb含量超标率为43.2%,Cd为18.6%,Zn和Cu则小于5%.由此可见,崇明岛主要公路两侧土壤污染以Cd为主,而蔬菜污染则以Pb为主.在长期运营的前提下,低交通量公路两侧50 m范围内耕作层土壤和两侧作物会发生一定程度的重金属污染,路面灰尘是路侧土壤和蔬菜的潜在污染源. 相似文献
40.
海南岛地表水的区域地球化学特征及其影响因素 总被引:1,自引:1,他引:0
始于2004年的海南岛多目标生态地球化学调查,对全岛的地表水进行了区域调查取样,分析测试了24项指标(部分样品增加测试12项)。测试结果表明,大多数指标优于国家地表水环境质量标准(GB3838-2002)中III类水体水质标准,只有Hg和总氮存在区域性的超Ⅲ类水体水质。经对样品的聚类分析研究表明,全岛地表水样品主要分为4类,分别反映了地表植被、海水入侵、灌溉水田排水、矿山废水排放对地表水化学成分的控制作用。在此认识的基础上,依地表水样品所处的土地利用方式的不同,按一定顺序对样品进行编号赋值(沿海的土地视为"海洋利用方式"),该赋值与聚类分析所得到的样品类别值之间存在极显著的正相关性,相关系数达0.8280,表明海南岛的土地利用方式是控制地表水地球化学特征的关键因素,从而为海南岛地表水环境质量的保护和提高指出了方向。 相似文献