共查询到18条相似文献,搜索用时 46 毫秒
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于2005年9月~12月对湘江株洲江段的软体动物进行了系统的调查.经分类鉴定,计有软体动物8科20属44种,其中腹足纲5科10属22种,双壳纲3科10属22种.腹足纲以田螺科为主,双壳纲以蚌科为主.其区系成分,东洋界与古北界相互渗透,但以东洋界华中区的种类优势明显.沿江城镇适量生活污水排入江中,可以适当增加软体动物的种类和数量;大量生活污水和工业废水未经处理排入江中,使其种类和数量显著减少.株洲航电枢纽建成蓄水,对库区的软体动物冲击较大,由于水位抬高,环境骤变,其种类和种群数量明显减少,尤其是双壳类. 相似文献
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2005—2006年对湘江干流15个县(市)36个采集点的软体动物的种类、分布及种群数量进行了系统调查,计有软体动物72种,隶属2纲10科29属,其中腹足纲38种,双壳纲34种;内有10种为湖南省新记录种,42种为中国特有种。发现一种近60年未被采到过的物种——湖南湄公螺(Mekonia hunanensis),已被《中国物种红色名录》定为灭绝的物种。湘江软体动物的区系成分属于东洋界类型,明显地反映出亚热带的特点。文章对湘江软体动物的种类分布和种群数量及其上、中、下游种类与种群数量的差异进行了分析,并根据12个与影响因子相关采集点软体动物的物种数和多样性指数,分析了城镇污水、水电工程和采砂对湘江软体动物的影响。 相似文献
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系统地调查了湘江中游江段软体动物的种类组成、分布、种群数量;借助多样性分析软件对14个生境的软体动物的物种丰富度指数(DMA)、Shannon-Wiener多样性指数(H′)、均匀度指数(Jsw)进行了计算;用Srensen相似性系数C对不同生境软体动物群落进行了系统聚类分析。研究结果表明,湘江中游计有软体动物53种,分别隶属于9科20属,其中腹足纲6科12属31种,主要是田螺科的种类;双壳纲3科8属22种,主要是蚌科的种类。湘江中游共有10个优势种、22个常见种、21个罕见种;14个生境的物种丰富度指数DMA的取值范围在6.4319~2.3183之间,Shannon-Wiener多样性指数H′的范围在3.3859~2.1834之间,均匀度指数Jsw在0.94808~0.82067之间。根据不同生境物种的相似性系数C进行系统聚类分析,14个生境的群落相似性系数在0.5236的水平时全部聚合在一起。探讨了湘江中游建坝对软体动物多样性的影响,并进一步分析了株洲市大桥采集点软体动物多样性最高的原因。 相似文献
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中国海典型生境双壳类软体动物多样性特点 总被引:2,自引:1,他引:2
中国海域广阔、海岸线绵长、环境复杂、包含的生境多样,对中国海典型生境中双壳类软体动物多样性的分析,可以反映中国海双壳类软体动物的区系特点.作者根据多年的研究成果和国内外贝类学家的报道,对不同典型生境的双壳类软体动物的多样性特点、生活环境、生态习性进行了阐述,对不同海区的双壳类软体动物的分布特点进行了分析.由于沿岸水、冷... 相似文献
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湘江中游江段螺类的种类组成及区系分析 总被引:6,自引:0,他引:6
报道了湘江中游江段螺类的调查结果,计有螺类31种(其中5种为湖南省新记录),分别隶属于腹足纲6科11属,其中主要是田螺科的种类.对它们的种类组成、区系、种群大小、分布与栖息环境的关系进行了分析,并讨论了城镇污水未经处理直接排放及修河拦坝对螺类生存环境的影响. 相似文献
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于1995 ̄1997年间对温岭海区潮间带软体动物进行了初步调查,共采获标本816号,经鉴定得:多板纲4科4种、双壳纲10科22种、腹足纲12科29种。还报道了该地海区潮间带软体动物的组成、地理分布特点,并提出了经济利用意见。 相似文献
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中国典型地带土壤原生动物:Ⅰ.区系特征和物种分布 总被引:25,自引:0,他引:25
研究中国典型地带土壤原生动物区系特征和物种分布。结果表明,鞭毛虫以波豆虫类和变形鞭毛虫类种类最多,其次为金滴虫类和无色眼虫类。肉足虫以有壳种类占优势,其中又以表壳目种类最多。纤毛虫最重要的3个类群为下毛目、肾形目和前口目,其中又以下毛目种类最丰富。凋落物层的种类多于0~5cm土壤层,其原因在于凋落物层具有比0~5cm土壤层更为优越的生态环境条件。290种原生动物中,中热带分布有72种,北热带106种,亚热带168种,暖温带116种,温带108种,高寒带73种。分布于各地带的物种的多少与各地带样点的土壤类型及土质密切相关。物种分布情况及区系相似性分析结果表明,土壤原生动物的大多数种类既非广泛分布的,其分布受地理地带的限制;也非随遇的,因小生境不同,种类分布有很大差异。 相似文献
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Eleni Voultsiadou 《Helgoland Marine Research》2005,59(3):237-251
The purpose of this paper was to investigate patterns of demosponge distribution along gradients of environmental conditions in the biogeographical subzones of the eastern Mediterranean (Aegean and Levantine Sea). The Aegean Sea was divided into six major areas on the basis of its geomorphology and bathymetry. Two areas of the Levantine Sea were additionally considered. All available data on demosponge species numbers and abundance in each area, as well as their vertical and general geographical distribution were taken from the literature. Multivariate analysis revealed a NW–SE faunal gradient, showing an apparent dissimilarity among the North Aegean, the South Aegean and the Levantine Sea, which agrees with the differences in the geographical, physicochemical and biological characteristics of the three areas. The majority of demosponge species has been recorded in the North Aegean, while the South Aegean is closer, in terms of demosponge diversity, to the oligotrophic Levantine Sea. The number of studies in the Aegean and Levantine subareas was positively correlated with the number of species recorded within each Aegean subarea. Demosponge species with an Altanto-Mediterranean distribution prevailed in the Aegean and the Levantine. The reduced contribution of the endemic component, as compared to the western Mediterranean, is consistent with the general NW–SE decrease in the number of endemic species in the Mediterranean. Demosponge distribution at the order level showed also a NW–SE gradient, similar to that observed in the entire Atlantic–Mediterranean region, suggesting a warm water affinity. Sublittoral, circalittoral and bathyal zones were clearly distinguishable in the Aegean Sea on the basis of their sponge fauna. The total number of species was an exponential negative function of depth. 相似文献
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Based on the surveying data obtained in February, May, August and November, 1987, the ecology of Mollusca in mangrove areas in the estuary of the Jiulong River in Fujian Province was studied. The results are as follows: There are 52 species of Mollusca in the areas, and species and abundance distribution increase with salinity. Biomass and density average 7.99 g m2 and 25 ind. m2 respectively, with higher values in autumn and winter, and lower in spring and summer. Vertical distribution of biomass is highest in high tide zones and lowest in low tide zones, and density is highest in mid-tide zones and lowest in tide zones. The relationship between the distribution of Mollusca and the environmental factors are discussed. 相似文献
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2005年8月,对云南富宁县驮娘江流域的鱼类进行了考察,采集到鱼类标本38种,发现云南鱼类3新记录:胡鮈(Huigobio chenhsienensiss Fang)、宽头盘鮈 (Discogobio laticeps Chu, Cui & Zhou)、圆体爬岩鳅 (Beaufortia cyclica Chen)。结合历史记录和中国科学院昆明动物研究所鱼类标本馆馆藏的驮娘江流域的鱼类标本,对驮娘江鱼类的目、科、属三个级别进行区系存在度分析。区系存在度分析显示:一些世界性分布的科和属,在驮娘江分布的种类并不很多,相反,一些具有地方性分布和小的科和属,其区系存在度相对较大。长臀鮠科(Cranoglanididae)为中国华南区-越南特有的科,其区系存在度为100%。结鱼属(Parator)和红鲌属(Erythroculter)为单种属,区系存在度为100%,结鱼属是中国特有属,主要分布在珠江水系,红鲌属鱼类主要分布在亚洲南部。这些地方性分布的小科属更能反映本地区的鱼类区系特征,即亚洲亚热带淡水鱼类区系。 相似文献
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Tobias Tamelander Caroline Kivimäe Richard G. J. Bellerby Paul E. Renaud Svein Kristiansen 《Hydrobiologia》2009,630(1):63-73
Floods are fundamental for the maintenance of floodplain biodiversity. As a result, well-functioning floodplains are characterized by a high spatio-temporal heterogeneity. Most floodplain-organisms need this shifting landscape mosaic to fulfil their environmental requirements and display a range of adaptations to survive floods. However, in temperate areas, where winter floods are common, extraordinary floods occurring in summer, a period of high physiological activity, may seriously impact the floodplain fauna. This is especially true for guilds characterized by low mobility, such as molluscs. Here we examined the immediate and longer-term response of Elbe grassland molluscs to the extreme 2002 Elbe summer flood in terms of abundance, diversity, and community composition by comparing pre- and post-flood data collected with identical methods. The flood favoured the colonization of aquatic species and led to a shift of the community towards a more hydrophilic composition. Both diversity and abundance increased significantly in the first year following the flood but decreased later gradually to the pre-flood levels. The high spatio-temporal habitat heterogeneity played an important part in the maintenance of mollusc diversity by increasing refuge opportunities and favouring the maintenance of various mollusc communities with different environmental requirements within the floodplain. Handling editor: S. I. Dodson 相似文献
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2011年3月、6月、9月和12月对淮河干流11个采集点的底栖软体类动物群落结构进行了调查研究, 共记录了软体类动物9科26种, 其中位于最上游的桐柏金庄种类最少, 仅有3种分布, 而位于中下游的新城口种类达到15种。总体上看, 自上游至下游, 软体动物种类的数量呈现一定的增多趋势。Pearson相关性检验结果表明软体动物种类数量和生物密度与河道深度间分别存在显著的正相关(r=0.617, P=0.043, n=11)和负相关关系(r=-0.654, P=0.029, n=11)。方差分析(One-way ANOVA)结果表明, Shannon-Wiener多样性指数[F(3, 40) =0.225, P=0.879]、Margalef丰富度指数[F(3, 40) =0.902, P=0.449]、Pielou均匀性指数[F(3, 40) =0.841, P=0.479]这3种指数以及生物量[F(3, 40) =1.931, P=0.14]不存在显著的季节性变化, 但生物密度[F(3, 40) =5.45, P=0.003]却存在极显著的季节性变化。其中, 生物密度在6月份出现峰值[(90.13 36.31) ind./m2], 最低值出现在12月份[(14.42 2.78) ind./m2]; 生物量的变化不与生物密度变化同步, 其峰值出现在9月份[(155.08 50.43) g/m2], 最低值则出现在3月份[(39.15 14.08) g/m2]。相似性分析(One-way ANOSIM)结果表明, 软体类动物群落在生物密度和生物量方面的优势物种组成上均无显著的季节性差异, 其P值分别为0.082和0.514。生物密度在不同月份间的不相似百分比变化幅度从53.87%至59.12%, 而生物量的不相似百分比变化幅度则从58.76%至68.58%。冗余分析(Redundancy Analysis RDA)结果表明, 河宽、水深和砂质型底质为影响淮河干流底栖软体类动物分布的主要环境因子。 相似文献
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研究了长江流域十余个水体水栖寡毛类的区系组成及分布。共鉴定水栖寡毛类53种,隶3科27属,其中仙女虫科15属31种(占58.49%);颤蚓科11属20种(占37.74%);线蚓科1属2种(占3.77%).在河流、草型湖泊和藻型湖泊这三类水体中,以草型湖泊的物种数最多,达36种;其次为长江干流,34种;藻型湖泊仅24种。对寡毛类的种间关系及不同生境寡毛类种类组成的相似性进行了聚类分析,结果表明,寡毛类的种类分布具有明显的地域性,据此可将其划分为6类(A-F组). 相似文献