黄河口潮间带大型底栖动物群落特征

2013年2月、5月和8月对黄河入海口附近潮间带的大型底栖动物进行了调查,调查工作涵盖3个季节2条断面的样品,分析了黄河口潮间带大型底栖动物的群落结构特征,包括群落种类组成、丰度和生物量、优势种、多样性,采用CLUSTER聚类分析了大型底栖动物的群落结构,并用AMBI和m-AMBI对底栖群落和环境质量进行了评估。本次调查共鉴定出大型底栖动物52种,其中,多毛纲动物24种,软体动物14种,甲壳动物12种,鱼类1种,纽虫1种。多毛纲动物为该海域底栖群落的主要成分,占据了群落总种数的46.15%。从季节来看,物种数春季最高(38种),夏季则处于最低水平(16种)。群落丰度和生物量均具有明显的季节变化,丰度在春季达到最高,为3 549.33 ind/m2,远高于冬季的256.67 ind/m2和夏季的100.67 ind/m2,其中扁玉螺(Neverita didyma)是丰度的主要贡献者,贡献了全年群落总丰度的75.44%。生物量春季最高,夏季次之,冬季最低。在全年尺度上,甲壳动物的日本大眼蟹(Macrophthalmusjaponicus)是生物量的主要贡献者,占据总生物量的49.86%。群落的季节变化也得到了群落CLUSTER分析与SIMPER分析结果的验证。这与黄河入海口附近底质不稳定,易受侵蚀、环境条件如盐度等具有明显季节差异,以及一定程度的人为扰动密切相关。AMBI和m-AMBI的分析结果显示,该区域环境质量状况较好,仅受到了轻微扰动影响。     

乳山湾潮间带春季大型底栖动物群落结构

于2011年5月对乳山湾潮间带8条断面的大型底栖动物进行了定量调查,共鉴定出大型底栖动物116种,其中多毛类58种、软体动物15种、甲壳类27种、棘皮动物3种,其他动物13种.调查潮间带大型底栖动物的平均丰度为872.6 ind·m-2,平均生物量为9.37g·m-2,根据相对重要性指数(IRI)计算优势种为中蚓虫、沈氏厚蟹、纽虫和刺沙蚕等.丰富度指数(d)、多样性指数(H)和均匀度指数(J)平均值分别为2.119、2.384和0.608,为轻度污染海域.以30%的相似性尺度,可将所调查潮间带8个断面划分为3个群落.与同纬度海湾潮间带相比,乳山湾潮间带大型底栖动物具有种数多、个体小、丰度高的特点,仅从大型底栖动物群落结构和多样性指数方面不足以证实该海域贝类养殖对环境产生扰动并对底栖动物群落造成影响,还需要进行更深入的调查研究来综合判断.     

洋山港潮间带大型底栖动物群落结构及多样性

2009-2010年在洋山港海域大洋山岛和圣姑礁进行四个季度潮间带大型底栖动物生态学研究。共采集到大型底栖动物61种,以广布种为主,部分为河口低盐种,其中软体动物22种,环节动物16种,节肢动物12种,苔藓动物5种,腔肠动物4种,星虫动物和棘皮动物各1种。优势种为短滨螺(Littorina brevicula)、多齿围沙蚕(Perinereis nuntia)、日本笠藤壶(Tetraclita japonica)、齿纹蜒螺(Nerita yoldii)和特异大权蟹(Macromedaeus distinguendus)。丰度和生物量在不同季节明显不同(P<0.05):丰度的最高值出现在春季,为(3204.9±837.84)个/m²,最低值出现在秋季,仅为(2213.2±731.27)个/m²;生物量的最高值则出现在夏季(2233.2±1493.42)g/m²,冬季最少,仅为(819.95±484.80) g/m²。大洋山岛和圣姑礁的丰度和生物量具有较大差异(P<0.05):年均丰度以大洋山断面较高,为(3090±742.74)个/m²,圣姑礁断面较低,为(2133±372.51)个/m²;而年均生物量则以圣姑礁断面较高,为(1711.1±1180.76) g/m²,大洋山断面较低,仅为(1028.5±627.61) g/m²。运用ABC曲线、等级聚类和MDS对大型底栖动物群落结构分析发现:大洋山潮带间大型底栖动物群落尚未受到干扰或干扰较轻,群落结构相对稳定;而圣姑礁断面的潮间带大型底栖动物群落受到了中度的干扰,群落结构稳定性下降。与15年前的研究相比,圣姑礁大型底栖动物的密度和生物量均有大幅度的降低,这与洋山港海域盐度的升高、生态环境变化和人为干扰强度增加等有关。     

珠江河口区大型底栖动物群落结构

河口区大型底栖动物具有的重要群落特征往往可以反映群落所经历的环境污染。为更好地了解珠江河口区大型底栖动物群落结构, 作者于2014年11月至2015年8月进行了4个季度的大型底栖动物调查, 并利用PRIMER 6.0软件进行群落生物多样性指数计算、群落等级聚类(Cluster)和非度量多维标度排序(nMDS)分析。研究结果显示: 珠江河口区共获得大型底栖动物52种, 优势种包括光滑河篮蛤(Potamocorbula laevis)、中国绿螂(Glaucomya chinensis)、焦河篮蛤(Potamocorbula ustulata)和羽须鳃沙蚕(Dendroneris pinnaticirrus)。大型底栖动物年平均密度为269.3 ind./m ², 年平均生物量为129.61 g/m ²。12个站次的丰富度指数(D)、均匀度指数(J')和Shannon-Wiener多样性指数(H')平均值分别为1.81 ± 1.38、0.50 ± 0.27和1.60 ± 1.13。该结果显示除P01断面的秋季和冬季环境质量为优良外, 其他站位在不同季度都显示出轻度到重度的污染。Cluster聚类分析和nMDS标序结果表明, P01断面与P02和P03断面群落相似度较低, 与断面地理分布情况一致; P02断面和P03断面存在交叉聚集, 群落相似度较高。结合环境因子结果可知, 沉积物理化因子与群落分布特征相关性较大, 其中最能解释珠江河口区群落多样性分布特征的环境因子为盐度和pH值。     

宁波大榭开发区北岸潮间带春季大型底栖动物群落格局

为了解宁波大榭岛潮间带春季大型底栖动物群落结构与数量分布,探讨自然环境因子和人类活动对潮间带大型底栖动物种类组成及数量分布的影响,于2006年4月对大榭岛北岸岩礁相和泥沙相两种不同底质的潮间带大型底栖动物进行采样分析.研究表明:(1)岩礁相断面和泥沙相断面共发现大型底栖动物39种,其中贝类20种,多毛类8种,甲壳类8种;(2)岩礁相断面19种,主要以贝类生物为主,达16种,甲壳类只有2种;泥沙相断面20种,贝类、多毛类和甲壳类分布较为均匀,分别为4种、6种和8种;(3)岩礁相断面和泥沙相断面平均栖息密度分别为583.33 ind/m2和32 ind/m2,平均生物量分别为638.56 g/m2和7.83 g/m2,岩礁相断面栖息密度和生物量均远高于泥沙相断面;(4)岩礁相断面大型底栖动物群落垂直变化较泥沙相断面显著.     

安徽南漪湖大型底栖动物群落结构

2002年7月至2004年7月,对安徽南漪湖12个采样点的大型底栖动物群落结构进行了调查研究,共获得大型底栖动物39种,隶属于3门28属。大型底栖动物的现存量在2003年冬季出现最高值,密度最低值出现在2004年夏季。软体动物的现存量占绝对优势,其优势种为河蚬(Corbicula fluminea)、梨形环棱螺(Bellamya purificata)、铜锈环棱螺(B.aeruginosa)和长角涵螺(Alocinma longicornis)。Shannon-Wiener多样性指数、Margalef多样性指数和Pielou指数的年均值分别为0.83、0.51和0.77。南漪湖西部物种数、物种多样性、现存量均较东部高。建闸蓄水后,南漪湖的环境发生了很大的改变,随水深增加,大型底栖动物的现存量呈明显下降的趋势。     

胶州湾潮间带大型底栖动物的群落生态

潮间带是沿岸带位于最大高潮水面到最小低潮水面之间的区域,处于陆海过渡带,生物资源非常丰富,也是受各种理化环境因子以及人类活动影响最大的区域。我国近年来对各地不同类型的潮间带进行了一些生态调查研究,包括对胶州湾也进行了数次生态调查,如劭晓阳等(2001)研究了浙江省岛     

泉州湾蟳埔潮间带大型底栖动物群落的时空分布

为了比较泉州湾蟳埔潮间带沙滩、互花米草滩和牡蛎石泥滩3种生境(3个潮层)的大型底栖动物群落,2011年4月至2012年1月对3种生境的大型底栖动物进行了季度定量取样。在3种生境共获得85种大型底栖动物,其中环节动物39种,软体动物20种,节肢动物21种,刺胞动物、扁形动物、纽虫动物、星虫动物和脊索动物各1种。多维标度排序(MDS)分析表明,春季和冬季泉州湾蟳埔潮间带3种生境的大型底栖动物群落相似性较低;夏季和秋季互花米草滩与牡蛎石泥滩的大型底栖动物群落相似性较高,而与沙滩的大型底栖动物群落相似性较低。沙滩大型底栖动物群落的季节变化较明显,其次是牡蛎石泥滩,而互花米草滩大型底栖动物群落的季节变化较不明显。大型底栖动物栖息密度和生物量随着潮层降低而增加。单变量双因素方差分析(Two-way ANOVA)表明,不同生境之间的大型底栖动物物种数、栖息密度、多样性指数、均匀度指数和丰度指数有显著差异,但生物量无显著差异,这是因为沙滩的物种数较少,栖息密度较低,但优势种弧边招潮蟹(Uca arcuata)个体较大,互花米草滩和牡蛎石泥滩的优势种为加州中蚓虫(Mediomastus californiensis),个体相对弧边招潮蟹小。不同季节之间大型底栖动物物种数、栖息密度、生物量和丰度指数有显著差异,但多样性指数和均匀度指数元显著差异,这是因为沙滩物种数少,但个体分布比较均匀,而互花米草滩和牡蛎石泥滩物种数较多,个体分布较不均匀。以上结果表明,潮汐、沉积物粒径和生境是影响潮间带大型底栖动物群落的主要因素。潮汐导致潮间带的空间异质性,空间异质性导致大型底栖动物群落的差异。     

厦门凤林红树林湿地大型底栖动物群落

为摸清厦门集美凤林红树林湿地的大型底栖动物群落结构及其多样性现状,2002年1、4、7和10月在厦门集美凤林红树林区进行大型底栖动物调查,4个季度共获得大型底栖动物42种。生物量优势种是软体动物门的珠带拟蟹守螺(Cerithideacingulata)和节肢动物门的弧边招潮(Ucaarcuata)。密度优势种是软体动物门的短拟沼螺(Assimineabrevicula)和环节动物门的沼蚓(Limnodriloidessp.)。集美凤林红树林区大型底栖动物年平均密度和年平均生物量分别为1,990ind./m2和139.0g/m2。密度的季节变化是:1月>4月>10月>7月,生物量的季节变化是1月>10月>4月>7月。聚类分析和数量分布表明,优势种珠带拟蟹守螺、短拟沼螺、弧边招潮和沼蚓的季节变化各不相同。与2002年10月深圳湾福田红树林区大型底栖动物群落的物种多样性指数平均值(0.56)比较,厦门凤林红树林区的平均值较高(2.66)。文中分析了影响大型底栖动物多样性的环境因素。     

长江口附近海域大型底栖动物群落特征

利用2002年9月在长江口附近海域进行的大型底栖动物定量采集样品,采用物种优势度计算方法和大型多元统计分析软件PRIMER,研究了该海域大型底栖动物群落的优势种组成和物种多样性、生物量和丰度、群落等级聚类分析(CLUSTER)和非度量MDS标序以及群落受污染扰动情况。本次调查共获得长江口附近海域大型底栖动物154种,其中多毛类环节动物60种,甲壳动物30种,软体动物28种,棘皮动物25种,其它类群动物11种。群落中优势种的地位都不明显,只有虫(Listriolobussp.)、豆形短眼蟹(Xenophthalmus pinnotheroidesWhite)、拟单指虫(Cossurella dimorphaHartman)为相对重要的种类。栖息种数、平均生物量和丰度以及3个多样性指数H′、D和J的空间分布无明显的规律,在122°E以东海域呈不连续的斑块或镶嵌状分布。群落结构聚类分析和MDS标序表明,20个取样站的群落结构相似性程度都非常低,为10%-30%,仅有A12和E4两个站Bray-Curtis相似性系数达到50%。ABC曲线表明,近长江口的A4站和A14站的底栖动物群落已有受到一定程度的轻微污染扰动的趋势;而距长江口较远的P9和P5两站ABC曲线状况正常,表明该处的大型底栖动物群落尚未受到干扰。     

Ecological context of savanna chimpanzee (Pan troglodytes verus) termite fishing at Fongoli, Senegal

Chimpanzees (Pan troglodytes verus) at Fongoli, Senegal, consume termites year-round. Understanding the ecological context behind this behavior is especially important in light of the environmental conditions at Fongoli. This mosaic savanna habitat is one of the hottest and driest sites where chimpanzees have been studied. Two genera and four species of termites were found in association with tools used by chimpanzees in a sample of 124 termite mounds that were monitored. The chimpanzees of Fongoli termite fish predominantly in woodland and forest habitat types, and, although woodland accounts for the majority of the chimpanzees' home range, forest habitat types comprise only about 4% of their range. Thus, habitat type has an influence on the Fongoli chimpanzees' termite fishing. Termite consumption to the degree seen at Fongoli may have particular significance for hominid evolution, given the expansion of Pliocene hominids into increasingly open, hot, and dry habitats.     

南沙群岛渚碧礁大型底栖动物群落特征

利用2002年5月12日至5月21日在南沙群岛渚碧礁用轻潜水(SCUBA)方法于该礁盘不同位置设立的4个定量取样站采集的调查资料,采用IRI指数、ABC曲线方法和大型多元统计分析软件PRIMER对渚碧礁大型底栖动物进行等级聚类分析(CLUSTER)和非度量MDS标序,研究群落结构格局以及用Shannon-Wiener指数、物种丰富度指数和物种均匀度指数分析物种多样性和群落种类组成的相似程度,对渚碧礁大型底栖动物的群落结构进行了初步研究。结果表明:调查获得渚碧礁调查站大型底栖动物总种数314种,平均栖息密度为357.94个/m2,平均生物量为64.85g/m2;群落中主要的重要种或优势种为粗糙毛壳蟹(Pilodius scabriculus)和鼓虾(Alpheus spp.),但IRI指数相对较低;群落结构聚类分析和MDS标序表明,4个取样站的群落结构非常相似,Bray-Curtis相似性系数达到80%以上。     

Seasonal Dynamics of Soft Bottom Macrobenthic Communities of the Sublittoral in Peter the Great Bay, Sea of Japan

Seasonal dynamics of macrobenthos were studied at five stations located at depths of 10–60 min in the Far East State Marine Reserve (southern Peter the Great Bay) during 1984–1987. Sampling was conducted at stations once per season. Stable seasonal fluctuations of the population density and the biomass in basic taxonomic groups were found. As a rule, the quantitative parameters were augmented in spring and summer, and decreased in fall and winter. This was caused, first of all, by summer fluctuations of the number of small and short-lived species of polychaetes and bivalve molluscs. The amplitude of fluctuations decreased with increasing depth. Variation in the quantitative parameters was significant at the community level only at the most shallow-water stations. It was assumed that this phenomenon might be caused by the seasonal consumption of macrobenthos by bottom fish and by the periodicity of detritus supply to the bottom from the water column with a background of varying environmental temperature parameters and of mass settling of benthic larvae. The seasonal changes in parameters began and ceased earlier in 1986–1987 than 1984–1985, which was related to an appreciable decrease in water temperature in 1986. During the period of study, an increasing trend of parameters, apparently part of a long-term cycle, was recorded both for individual groups and for entire communities, and was the most appreciable at greater depths (47–60 m).     

Oil Palm Use by Adjacent Communities of Chimpanzees at Bossou and Nimba Mountains,West Africa

We investigated oil palm (Elaeis guineensis) use for feeding in 3 chimpanzee communities: Bossou and Seringbara in Guinea and Yealé in Côte d'Ivoire. Bossou was used as the benchmark for comparison. Bossou chimpanzees (Pan troglodytes verus) exhibit a wide range of oil palm targeted behaviors. We used direct observations of their two tool use, i.e., nut-cracking and pestle pounding, to establish strict and reliable criteria to ascertain the presence of comparable behaviors at the two adjacent Nimba sites. Based on monthly surveys of oil palms across the three sites, significant differences in patterns of use emerged. Bossou chimpanzees demonstrated the greatest frequency of oil palm use, while Seringbara chimpanzees, 6 km away, failed to exhibit any use and Yealé chimpanzees, 12 km away, showed all uses comparable to Bossou chimpanzees except pestle pounding and mature leaf pith-feeding. We examined the density and distribution of oil palms, tool availability for nut-cracking and pestle pounding, fruit, flower and nut availability, competition with sympatric species for fruit and nuts and the diversity of fruit species in the diet across the 3 sites. We found no clear difference in proximate environmental variables underlying observed variations in oil palm use among the 3 sites, yielding the conclusion that the differences are cultural. Assuming individual interchange between communities and the involvement of social learning in the intracommunity transmission and maintenance of oil palm uses, the result raises interesting questions about diffusion of behavior between neighboring chimpanzee communities.     

Linking Physiology To Ecological Function: Environmental Conditions Affect Performance And Size Of The Intertidal Kelp Hedophyllum Sessile (Laminariales,Phaeophyceae)

For autogenic ecosystem engineers, body size is an aspect of individual performance that has direct connections to community structure; yet the complex morphology of these species can make it difficult to draw clear connections between the environment and performance. We combined laboratory experiments and field surveys to test the hypothesis that individual body size was determined by disparate localized physiological responses to environmental conditions across the complex thallus of the intertidal kelp Hedophyllum sessile, a canopy‐forming physical ecosystem engineer. We documented substantial (> 40%) declines in whole‐thallus photosynthetic potential (as Maximum Quantum Yield, MQY) as a consequence of emersion, which were related to greater than 10‐fold increases in intra‐thallus MQY variability (as Coefficient of Variation). In laboratory experiments, desiccation and high light levels during emersion led to lasting impairment of photosynthetic potential and an immediate > 25% reduction in area due to tissue contraction, which was followed by complete loss of structural integrity after three days of submersion. Tissue exposed to desiccation and high light during emersion had higher nitrogen concentrations and lower phlorotannin concentrations than tissue in control treatments (on average 1.36 and 0.1x controls, respectively), suggesting that conditions during emersion have the potential to affect food quality for consumers. Our data indicate that the complex thallus morphology of H. sessile may be critical to this kelp’s ability to persist in the intertidal zone despite the physiological challenges of emersion and encourage a more nuanced view of the concept of “sub‐lethal stress” on the scale of the whole individual.     

Characterization,Ecological Status and Type-specific Reference Conditions of Surface Water Bodies in Wallonia (Belgium) using Biocenotic Metrics based on Benthic Invertebrate Communities

The river types in Wallonia (Belgium) were defined according to the system B of the European Water Framework Directive (WFD) taking into account obligatory and optional factors synthesized in three criteria: ‘size’, ‘slope’ and ‘natural region’. Under the hypothesis that benthic invertebrate assemblages would be specialized according to river type, a set of 627 faunal samples originating from an 11-year sampling period was tested to characterize river types with faunal assemblages. A multivariate approach led to gather 23 river types into seven groups exhibiting similar faunal assemblages. Using biocenotic metrics based on benthic invertebrate assemblages (e.g., the French standard IBGN), type-specific reference conditions and ecological status class limits were defined for each ‘natural’ river type group. Ecological potential was defined for heavily modified and for artificial (i.e., man-made canals) types. An ‘ecological status’ evaluation strategy was therefore developed and applied in the southern – and more natural – part of Wallonia, where many reference sites were available. In the northern part of Wallonia (i.e., the ‘Loess region’) where no high quality site was available, the expert judgement took a larger part in the definition of the reference conditions and of the ecological status class limits, in addition to the calculations. Two independent distribution gradients of taxa assemblages resulted from multivariate ordination: a first ‘saprobity axis’, as the taxa-sensitivity to organic contamination was increasing from ‘very resistant’ taxa (mainly located in the ‘Loess region’) to ‘sensitive’ and ‘very sensitive’ taxa (from the river types belonging to the Condroz, the Famenne, the Arden and the Jurassic regions) and a second axis characterizing the Meuse-specific faunal assemblage, gathering exotic species and typical limnophilous taxa of large heavily modified rivers. The ecological status monitoring management system developed in this study – i.e., the definition of faunal river type groups, related reference conditions and ecological status class limits – represents a proposal to be integrated in the ecological status assessment of biological elements for the implementation of the WFD and was tested in Wallonia. For the period 2000–2002 involving 349 different sites, the element ‘benthic invertebrate fauna’ was in that way classified ‘high status’ for 31.5% of sites, ‘good status’ for 31.5% and below ‘good status’ for 37% of sites. The best ecological status (i.e., 100% ‘high’ and ‘good’ status) was found in river type ‘Arden’s xenotrophic brooks with strong slope’ and in river types 8large rivers with medium slope’. The worst status was found in river types ‘Loess brooks and rivers with medium slope’.     

Selection of Competitive Strains of Rhizobium Nodulating Phaseolus Vulgaris and Adapted to Environmental Conditions in Egypt,Using the Gus-Reporter Gene Technique

Two Rhizobium etli strains, EBRI 2 and EBRI 26, isolated from Egypt were tested for nodulation competitiveness on beans using Rhizobium tropici CIAT 899G as the competing strain. The insertion of the gus-reporter transposon mTn5ssgusA30 did not alter the nodulation or nitrogen fixation capacity of mutant strain CIAT 899G compared to the wild type. At neutral pH, R. etli strains EBRI 2 and EBRI 26 were more competitive than CIAT 899G with the bean cultivar Saxa. These two strains gave nodule occupancies of 52.1 and 61.1% competing with equal cell numbers of CIAT 899G. Nodule occupancies from these two native strains increased with the bean cultivar Giza 6 from Egypt to 66 and 67.5%. Based on these results, cultivar Giza 6 was used to select the most competitive strains under stress of salinity or alkalinity as a major problem for a large part of Egyptian soils. Under stress of salinity (0.2% NaCl or 34.2 mM NaCl), the salt-sensitive strain EBRI 2 was more competitive than the salt-resistant strain EBRI 26. Strain EBRI 2 gave 87.4% but strain EBRI 26 gave 63.7% nodule occupancy against CIAT 899G. The same trend of results was observed under stress of alkalinity (pH 8). Strain EBRI 2 occupied 83% while Strain EBRI 26 occupied 53.2%.     

长江口及东海春季底栖硅藻、原生动物和小型底栖生物的生态特点

利用Ludox-QPS方法并结合沉积环境因子的综合分析,研究了2011年4月采自长江口及东海10个站位以底栖硅藻、纤毛虫和异养小鞭毛虫为代表的微型底栖生物及小型底栖生物的组成、丰度和生物量、分布及生态特点。结果表明,底栖硅藻的丰度 (5.92 ? 104 ind/10 cm2) 和生物量 (83.29 ?g C/10 cm2) 远高于纤毛虫 (丰度为1036 ind/10 cm2,生物量为3.33 ?g C/10 cm2)、异养小鞭毛虫 (丰度为4451 ind/10 cm2,生物量为2.51 ?g C/10 cm2) 和小型底栖生物 (丰度为1947 ? 849 ind/10 cm2,生物量为49.01? 22.05 ?g C/10 cm2)。在鉴定出的11个小型底栖生物类群中,线虫占小型底栖生物总丰度的90%和总生物量的37%。底栖硅藻生物量在长江口及东海海域呈由近岸向外海逐渐降低的分布特点,而底栖纤毛虫、异养小鞭毛虫及小型底栖生物的分布则正相反。在垂直分布上,76%的硅藻和80%的线虫分布在0–2 cm沉积物表层,仅1%的硅藻和6%的线虫分布在5–8 cm分层。统计分析表明,底栖硅藻的现存量与沉积物中叶绿素a含量呈极显著的正相关,与底层水温度呈弱的正相关;该海域底栖原生动物和小型底栖生物的分布受多个因子而非单一环境因子的共同作用。对比分析表明,长江口及东海单位体积沉积物中的硅藻丰度较水体中的硅藻丰度高2个数量级,沉积物中相当部分的叶绿素a含量可能系底栖硅藻所贡献;表层8 cm沉积物中纤毛虫的丰度约是上层30 m水柱中纤毛虫丰度的30倍,生物量约是后者的40倍。尽管纤毛虫在生物量上远小于小型底栖生物,但其估算的生产力约是后者的3倍;而异养小鞭毛虫由于个体更小,其周转率可能较纤毛虫更高。长江口及东海陆架区原生动物和小型底栖生物的高现存量及生产力预示着其在该海域生态系统中的重要作用。     

Ecological Risk Assessment of Arsenic and Metals in Surface Sediments from Estuarine and Coastal Areas of the Southern Bohai Sea,China

Distribution and magnitude of arsenic and metals in surface sediments collected from the coastal and estuarine areas of the southern Bohai Sea, China, were investigated. Sediments from the estuarine and coastal areas of the Jie and Xiaoqing Rivers contained highest concentrations of arsenic, cadmium, copper, mercury, and zinc. Mean concentrations of Cu, Zn, Cr, Pb, and Cd were higher than background concentrations determined for the areas. The magnitude of both enrichment factors (EF) and geoaccumulation indices (I_geo) suggested that pollution with As and metals was occurring along estuarine and coastal areas of the southern Bohai Sea. Risk analysis also suggested that concentrations of As and metals were sufficiently elevated as to cause adverse biological effects in the study area. According to the ecological risk index (RI) values, the upstream of the Jie River has a very high ecological risk for the waterbody. The data provided in this study are considered crucial for controlling and remediation of As and metals’ pollution of the southern Bohai Sea.