长山列岛邻近海域鱼类群落种类组成和多样性时空变化

为了解黄、渤海生态系统交错带长山列岛邻近水域鱼类群落种类组成和多样性,根据2016年10月,2017年1月、5月及8月进行的鱼类资源底拖网调查数据,应用相对重要性指数、物种多样性指数、k优势度曲线等方法,研究了长山列岛邻近海域鱼类群落种类组成、物种多样性时空变化及其与环境因子的关系。结果表明: 该海域共计捕获鱼类77种,以温水性、底层、洄游性鱼类为主,优势种组成季节变化明显,春季、冬季主要优势种为黄鮟鱇,夏季以日本鲭、鳀等中上层鱼类为主。全年共计出现洄游性鱼类46种,季节间物种迁移指数均在100以上,其中秋季物种迁移指数最大。鱼类群落物种丰富度指数在春季最高、Shannon多样性指数和均匀度指数在秋季最高。夏季物种丰富度指数与表层水温呈显著负相关;冬季物种丰富度指数与水深、底层水温呈极显著正相关,Shannon多样性指数与底层水温呈极显著正相关。长山列岛邻近海域作为黄、渤海两大生态系统的交错带,鱼类群落表现出高物种多样性、洄游种多以及明显的时空异质性。     

嘉陵江中游蓬安段鱼类群落功能多样性研究

研究调查了蓬安段2014—2019年洪水期 (6、7和8月)和枯水期 (11、12和1月)渔获物, 用11项鱼类功能性状类型结合蓬安段鱼类群落结构特点来分析该江段鱼类群落功能多样性在洪、枯期上的变化及与水环境的关系。研究结果表明, (1)2014—2019年洪水期的物种丰富度指数、辛普森多样性指数、Pielou均匀度指数和香浓威纳指数均高于枯水期; (2)SIMPER分析显示, 大鳍鳠Mystus macropterus、子陵吻鰕虎鱼Ctenogobius giurinus、似鳊Pseudobrama simoni、黄颡鱼Pelteobagrus fulvidraco、鳜Siniperca chuatsi、蛇 Saurogobio dabryi、飘鱼Pseudolaubuca sinensis、鲫Carassius auratus、黄尾鲴Xenocypris davidi和? Hemiculter leucisculus是造成洪水期与枯水期鱼类群落结构变化的主要差异贡献种; (3)各年份洪水期的功能丰富度FRic、功能离散度FDiv、功能散布度FDis和二次熵指数Rao及2015、2016和2017年的功能均匀度指数FEve均显著高于枯水期(P<0.05), 表明枯水期鱼群落的抵抗力稳定性和恢复力稳定性显著低于洪水期, 即枯水期水生生态系统功能较脆弱; (4)鱼类群落功能多样性与水环境因子存在显著相关关系, 但不同时期的功能多样性指数与环境因子相关性程度则呈现较大差异, 表明功能多样性是鱼类群落结构和各水环境因子综合作用的结果。     

胶州湾中部海域春、夏季鱼类群落结构特征

根据2009年3-8月在胶州湾中部海域逐月进行的定点底拖网调查数据,分析了胶州湾春、夏季鱼类群落种类组成,采用生态多样性指数分析了群落物种多样性,并用典范对应分析法研究了鱼类组成与主要环境因子的关系.结果表明：该海域共捕获鱼类43种,隶属于8目24科38属.种类数随底层水温的升高而增加.种类丰富度指数D变化范围为2.440～2.770,多样性指数H变化范围为1.322～2.346,均匀度指数J 变化范围为0.416～0.771,t检验表明春、夏季间各物种多样性指数均差异不显著(P>0.05).种类组成的秩相关性分析表明相邻月份鱼类组成及生物量大小的顺位基本稳定.典范对应分析结果表明影响胶州湾中部海域鱼类种类组成月间变化的主要环境因子为底层水温.     

漓江中下游鱼类物种组成及其多样性研究

2014年4月—2015年1月,按季度对漓江中下游进行了4次鱼类物种多样性调查研究,共采集鱼类10 161尾,计74种,隶属于5目15科55属。以鲤形目为主,占总物种数的66.67%,总个体数的64.29%;且鲤科占优势,占总个体数的59.30%。夏季鱼类多样性指数最高,物种最丰富,春季鱼类多样性相对较低,鱼类物种相对较少。秋冬两季多样性指数相差不大,鱼类的季节变化不明显;春季优势度指数λ最高,优势种较明显;鱼类群落结构相似性分析(ANOSIM)结果显示,平乐县鱼类群落结构与其他采样点间存在显著差异;但鱼类群落的季节性差异不明显。     

山东近海鱼类群落分类多样性

根据相关文献整理了山东近海鱼类名录,并根据1998—2009年山东近海鱼类调查名录,应用平均分类差异指数(Δ+)和分类差异变异指数(Λ+)研究了鱼类分类学多样性特征。结果表明,山东近海鱼类名录包括2纲28目91科169属225种,1998年调查仅2纲11目41科58属62种,2006年调查为1纲13目41科71属78种,2009年调查为1纲9目32科55属62种。1998年—2009年调查鱼类种类远远低于鱼类名录记录的种数,分类阶元包含指数较低,平均每属包含1.1种。根据山东近海鱼类名录计算鱼类平均分类差异指数为66.1,分类差异变异指数为141.7;1998—2009年历次调查鱼类平均分类差异指数在60.9—62.7之间,分类差异变异指数在65.4—92.3之间。将1998—2009年历次调查鱼类群落分类多样性指数计算值叠加到山东近海鱼类总名录的95%置信漏斗曲线图,结果表明大部分调查值在置信漏斗曲线之外,目前山东近海鱼类分类多样性已大幅下降。     

秋浦河源国家湿地公园溪流鱼类群落的时空格局

确定溪流鱼类群落的时空格局及其形成机制是开展鱼类物种多样性保护和管理的科学基础。该文于2012年5月和10月两次对秋浦河源国家湿地公园境内的24个可涉水河段取样,共采集鱼类29种,隶属10科4目。研究了溪流鱼类群落结构及其多样性的时空格局,并解析了局域栖息地条件与支流空间位置变量对鱼类群落的影响。鱼类多样性的时空变化显著,鱼类多样性总体上为二级溪流高于一级溪流,10月份高于5月份。流量量级、底质粗糙度及异质性、水温和水深等对鱼类多样性及群落结构的空间变化影响显著。鱼类群落结构符合嵌套格局,季节动态不显著,上游鱼类群落呈现为下游群落的嵌套子集。一、二级溪流间的群落结构尽管存在部分重叠但差异显著,且这种差异主要源于稀有花鳅(Cobitis rarus)、吻虾虎鱼(Ctenogobius spp.)、宽鳍鱲(Zacco platypus)、尖头鱥(Phoxinus oxycephalus)、高体鰟鲏(Rhodeus ocellatus)和原缨口鳅(Vanmanenia stenosoma)等鱼类相对多度的空间变化,其中,除尖头鱥的多度在一级溪流中更高外,其他5种鱼类均在在二级溪流更高。     

胶州湾海域鱼类群落种类组成及多样性

为了解胶州湾海域鱼类群落结构特征,根据2016—2017年间对胶州湾海域进行的4个航次底拖网调查数据,采用相对重要性指数、生态多样性指数和典范对应分析(canonical correspondence analysis,CCA)、非线性多维标度排序(non-metric multidimensional scaling,NMDS)等方法分析了胶州湾海域鱼类群落的种类组成和多样性特征。结果表明:调查共采集到鱼类46种,隶属2纲10目30科41属,以硬骨鱼纲鱼类为主(45种,97.83%)。其中,鲈形目(Perciformes)最多(22种,47.83%),其次是鲉形目(Scorpaeniformes),占15.22%。种类数季节变化明显,以夏季最高,23种;秋季最低,16种。优势种组成以赤鼻棱鳀(Thryssa kammalensis)、褐菖鲉(Sebastiscus marmoratus)、褐牙鲆(Paralichthys olivaceus)、大泷六线鱼(Hexagrammos otakii)、许氏平鮋(Sebastes schlegeli)和矛尾鰕虎鱼(Chaeturichthys stigmatias)等鱼类为主。多样性分析显示,鱼类物种多样性存在明显的季节差异。多样性指数(H′)季节变化范围为1.668—2.453,以夏季最高,春季最低;均匀度指数(J′)季节变化范围为0.577—0.808,以秋季最高,春季最低;丰富度指数(D′)季节变化范围为2.431—3.123,以冬季最高,秋季最低。典范对应分析表明,水温、盐度、水深和pH是影响胶州湾海域鱼类群落物种组成的主要环境因子,且水温和pH是影响鱼类群落结构及多样性时空变化的主要因子。与历史调查资料相比,由于人类活动对胶州湾生态系统的干扰,鱼类群落结构发生了较大变化,优势种组成更替明显,多样性水平降低,鱼类群落结构趋向简单化。     

GAM模型和BRT模型在长江口鱼类群落多样性预测中的比较

长江口为西太平洋最大的河口,评估其鱼类群落多样性分布能够为长江口生态系统的修复和管理提供科学依据.本研究基于2012—2014年长江口渔业监测数据,分别使用GAM模型和BRT模型建立各站点水域鱼类群落多样性指数与环境和时空因子之间的关系.结合线性回归方程,采用交叉验证的方式对模型的预测能力和拟合效果进行评价,并绘制了2014年长江口鱼类群落多样性指数和丰富度指数的空间分布图.结果表明: 盐度、pH和叶绿素a对多样性指数贡献最高,pH、溶解氧和叶绿素a是对丰富度指数贡献率最高的环境因子.BRT模型对于多样性指数和丰富度指数的拟合和预测结果均优于GAM模型.空间分布预测显示,相较于GAM模型,BRT模型能够对长江口小面积水域间的鱼类群落多样性作更好的区分,河口外侧水域的鱼类群落多样性明显高于河口内侧水域,而北支水域的多样性高于南支水域.     

渭河陕西段鱼类群落结构组成及变化研究

为了解渭河陕西段鱼类资源状况及其变化趋势, 于2016—2017年分4次对渭河陕西段的鱼类资源进行了调查。研究共调查到鱼类49种, 隶属于6目11科36属, 优势种为短须颌须(Gnathopogon imberbis)、拉氏大吻鱥(Rhynchocypris lagowskii)、棒花鱼(Abbottina rivularis)、?(Hemiculter leucisculus)、鲤(Cyprinus carpio)和鲢(Hypophthalmichthys molitrix)。与1984年调查结果比较分析发现: 该河段鱼类物种减少36种, 物种多样性下降明显; 相似度为0.49, 为中等不相似, 物种组成变化明显。经Shannon-wiener指数、Pielou’s指数、Marglef指数、Jaccard’s指数和G-F指数分析发现: 渭河陕西段鱼类物种组成已发生明显变化, 物种多样性下降60%。通过个体生态学分析, 渭河陕西段现存鱼类以喜缓流、杂食型、栖息于砾石底质类群为主, 群落结构已发生改变。研究表明: 该河段鱼类物种多样性下降明显, 群落结构已发生明显变化, 资源量明显下降; 水体污染、水资源减少和生境适宜度下降是导致鱼类群落结构变化的主要原因。     

长江中下游三个湖泊中鳜消化道寄生蠕虫群落的组成与多样性

鱼类在食物网中的营养位置对其消化道寄生蠕虫的群落结构有重要作用。本研究调查了梁子湖、洞庭湖、鄱阳湖中鳜(Siniperca chuatsi)消化道寄生蠕虫群落的组成和多样性。在3个湖泊中共发现11种寄生蠕虫, 优势种均为范尼道佛吸虫(Dollfustrema vaneyi), 频率分布中感染有12种寄生虫的样本占65%, 单个样本中最大物种数为6。3个湖泊中平均物种丰富度为1.532.13, Brillouin多样性指数为0.120.33, 其中鄱阳湖中的多样性最高。梁子湖和洞庭湖之间的Jaccard相似度和百分比相似指数最高。通过比较食物网中不同营养位置鱼类的消化道寄生蠕虫群落结构, 发现鳜的消化道寄生虫群落的物种丰富度与多样性水平都高于植食性和杂食性鱼类。研究还讨论了宿主食物组成对消化道寄生蠕虫群落结构的影响。       

江湖阻隔对长江中下游湖泊鱼类群落分类多样性的影响

基于1950s以来的长江中下游湖泊鱼类调查数据,分析通江湖泊与阻隔湖泊的鱼类分类多样性差异,以及通江和阻隔湖泊鱼类分类多样性的时间序列变化,探讨江湖阻隔对鱼类多样性的影响。结果显示,阻隔湖泊鱼类物种数、平均分类差异指数(Δ⁺)和分类差异变异指数(Λ⁺)平均值分别为48.47±14.64、74.02±3.09和736.89±33.80;通江湖泊为76.22±14.40、78.31±0.98和697.31±25.53。阻隔湖泊物种数和Δ⁺值显著低于通江湖泊(P<0.001),而阻隔湖泊Λ⁺值显著高于通江湖泊(P=0.002),表明阻隔湖泊物种间亲缘关系更近,均匀度下降,即物种分类单元减少,且集中分布于某几个分类阶元,稳定性变差。典型通江与阻隔湖泊鱼类群落分类多样性的时间变化分析发现,两种类型湖泊的鱼类物种数和Δ⁺值均随时间推移整体呈现下降趋势,Λ⁺值整体呈现升高趋势;并且阻隔湖泊的Λ+值随阻隔时间增加而大幅上升,Δ⁺和Λ^+...     

Fish fauna, biogeography and conservation of freshwater fish in Poyang Lake Basin, China

A checklist of the fish of Poyang Lake Basin based on an extensive survey and literature review is presented. A total of 220 species and subspecies belonging to12 orders, 27 families and 100 genera, have been recorded. Of these, 131 species are endemic to China. Based on cluster analysis with presence-absence data, freshwater ecosystems in Jiangxi Province are divided into two regions, the Xunwushui River region and the region of Poyang Lake. The Xunwushui River flows into the Pearl River, whereas the region of Poyang Lake flows into the Yangtze River. The fish fauna and evolution of the fish fauna in Poyang Lake Basin owes much to geological events and belongs to the Oriental Region, South-east Asiatic sub-region and East China area. Anthropogenic activities including habitat alteration, overfishing, pollution and soil erosion have severely reduced the fish biodiversity in Poyang Lake Basin. River modifications (i.e. dam construction and sand excavation) and heavy metal pollution are the most significant threats to fish diversity and ecosystem functioning in the majority of the river systems in the province. To protect fish diversity and fisheries more effectively in Poyang Lake Basin, law enforcement should be strengthened, and the following measures could be introduced: restocking economically important fish species; establishing fish sanctuaries and freshwater protected areas, ordering a close season and developing sustainable aquaculture.     

Measuring ecosystem degradation through half a century of fish species introductions and extirpations in a large isolated lake

The introduction of exotic species and the extirpation of native species that occurred during the past two centuries have strongly modified the structure of most plant and animal assemblages across the globe. Such a biotic change is particularly marked in isolated environments such as islands or isolated lakes. Most studies reported drastic changes between before and after human disturbances, but the dynamics of change in assemblage structure through the invasion and extirpation processes are rarely reported. Here we measured the aquatic ecosystem degradation through exotic species introduction and native species extirpation experienced by Lake Erhai (China) during the last 50 years using structural, functional and taxonomic distinctness biodiversity indices. Structural diversity (species richness) did not varied monotonically along the temporal gradient, due to an opposite trend between exotic species increase and a concomitant decline of native species richness. Functional diversity displayed unclear ascending trends driven by the introduction of exotic species having distinct functional traits than natives. Taxonomic distinctness indices exhibited an increase of the average taxonomic distinctness (Δ⁺), but a decrease of the variation in taxonomic distinctness (Λ⁺) through time. Structural, functional and distinctness indices providing complementary information on ecosystem degradation, we here proposed a new multifaceted degradation index integrating these three facets of biodiversity. Such an index provided an accurate representation of the faunistic changes experienced by Lake Erhai and might constitute a comprehensive way to measure ecosystem degradation through exotic fish species introductions and native fish species extirpations.     

鄱阳湖湖区及支流修水夏季鱼类系统发育群落结构分析

群落的物种共存及构建机制是生态学研究的核心问题之一, 系统发育群落结构分析为探究群落的构建机制提供了新的方法。研究在鄱阳湖湖区及其支流修水设立24个采样点, 采用系统发育群落结构的方法分析了不同空间尺度下鱼类群落的构建机制。结果表明: (1)鄱阳湖鱼类主要以鲤形目、鲤科鱼类为主, 表现出东亚江湖鱼类的组成特点; (2)依据物种组成和空间位置, 鄱阳湖湖区及修水鱼类群落属于不同的组群, 鄱阳湖湖区鱼类群落可以进一步分为北方群、南方群和东部群; (3)在采样点尺度, 24个采样点中, 有12个采样点靠近鄱阳湖支流的入湖口区域, 环境特别, 群落构成表现为环境过滤作用, 有12个采样点相对容纳了较多的远缘物种, 群落构成表现为竞争作用; 在区间分析的尺度, 北方群、东部群及修水群表现为竞争作用, 南方群表现为环境过滤作用; 在湖区及支流流域的尺度, 鄱阳湖湖区群为竞争作用, 修水群转变为环境过滤作用。因此, 鄱阳湖的湖区和支流修水等鱼类群落具有不同的物种组成和群落构建机制。研究结果加深了对群落构建机制的理解, 可以为鄱阳湖鱼类资源的保护提供参考。     

基于鱼类物种状况的长江生态环境质量评估

鱼类是水域生态系统的重要组成部分, 也是水域生态环境良好的指示类群。为合理评估长江生态环境的现状和变化趋势, 文章提出将土著鱼类物种数和珍稀特有鱼类物种数作为评价指标, 并建立了相关的评价基准和等级划分标准。以2010年和2020年为评价年, 评估了长江干流及代表性重点水域的生态环境质量。结果显示, 当前长江上游干流和下游干流的生态环境质量优于中游; 支流赤水河的生态环境质量良好, 大型湖泊鄱阳湖的生态环境质量中等。从时间上看, 随着长江十年禁渔等一系列保护措施的实施, 长江干流的生态环境质量有不同程度地好转。在此基础上, 提出了进一步改善长江生态环境的对策与建议。     

禁渔初期鄱阳湖鱼类时空分布特征

研究于2020—2021年使用Simrad EY60鱼探仪对鄱阳湖进行了秋季、春季和冬季共3次的水声学调查,并同步开展渔获物调查作为补充,分析鄱阳湖鱼类资源时空分布变化特征。结果表明:在季节分布上,鱼类目标强度和密度值都存在显著差异(P<0.05),在目标强度上表现为冬季[(–51.0±14.13) dB]>春季[(–52.10±4.59) dB]>秋季[(–52.71±9.95) dB],在鱼类密度上表现为冬季(54.61 ind./1000 m3)>秋季(46.10 ind./1000 m3)>春季(18.54 ind./1000 m3);在水平分布上,鱼类资源空间分布不均且不同湖区间有显著差异(P<0.05),秋季鱼类主要分布在中部湖区松门山,冬季鱼类主要分布在北部湖区通江水道;在垂直分布上,秋季和冬季均表现为底层>中层>表层,春季表现为表层>中层>底层。综合来看,鄱阳湖鱼类时空分布与鱼类的生活习性如产卵、育肥和越冬等因素密切相关。研究结果为从宏观空间尺度分析区域鱼类时空变动特征提供参考,也为鄱阳湖禁捕效果评估及生物完整...     

SPATIO-TEMPORAL VARIATIONS OF FISH ASSEMBLAGES IN THE DONGTING LAKE北大核心CSCD

Lake Dongting is the second largest floodplain lake along the Yangtze River basin. However, the study on fish communities in the Dongting Lake is limited, lacking systematic research on the spatio-temporal variations of fish assemblages in this area. Fish were sampled seasonally from December 2012 to October 2014 in the Dongting Lake. 80 fish species belonging to 54 genera, 17 families, and 7 orders with dominant Cyprinidae accounting for 58.8% of the total species were collected. The species richness reduced by 36 in contrast with the historic records. The number and percentage of riverine and river-sea migratory species decreased by 13 (2.2%) and 4 (3.0%) respectively in comparison with historic records. We detected significant seasonal and regional differences in species composition and biodiversity. The diversity and evenness of fishes were significantly higher in summer and autumn than those in other seasons. Meanwhile, significantly lower diversity was observed in the east Dongting Lake than other regions. Our results indicated that seasonal flood pulses and, assisting by river-lake connectivity may play a fundamental role for the fish resources supplement in floodplain lakes. This study demonstrated significant spatio-temporal variations of fish assemblages in the Dongting Lake, which provided scientific foundations for fish conservation in this area. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.     

BIODIVERSITY PATTERN AND CONSERVATION OF AQUATIC VASCULAR PLANTS IN THE YANGTZE RIVER BASIN,CHINA北大核心CSCD

The Yangtze River is the largest river in China. It is a priority conservation area for biodiversity of the world, with its main river, branches and wetlands. As an essential part of freshwater ecosystem, aquatic vegetation has been well studied by Chinese researchers since 1950s, but large-scaled analysis on the biodiversity pattern is lacked. Based on published studies, we analyzed spatial and temporal pattern of aquatic plant diversity in the Yangtze River Basin, and calculated the suitable habitat area and underlying influence of environmental factors using MaxEnt software. A total of 298 species are recognized, belonging to 121 genera in 52 families, which is 57.6% of the total aquatic vascular plants in China. The Yangtze River Basin is the key area for aquatic plant diversity of China, especially the subregions of middle reaches. The elevation and land use are the key environmental variables to the spatial pattern of aquatic plants. The separation among water systems have weak influence on the spatial pattern of diversity in aquatic vascular plants, but potamo-lacustrine habitats facilitated the species homogenization of the flora in a sub-basin scale. The network consists of Poyang Lake, Dongting Lake, Tai Lake, and the middle and lower mainstream is the suitable area for the aquatic plants based on the MaxEnt model. In the past half century, the decline or loss of aquatic vegetation occurred in plenty of lakes in the Yangtze River Basin. We suggested that the protection of aquatic vegetation should be incorporated into the integrated conservation of the middle and lower Yangtze River. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.     

Biodiversity pattern of fish assemblages in Poyang Lake Basin: Threat and conservation

Poyang Lake Basin is of great importance to maintain regional ecological balance. However, fish biodiversity in this basin has rapidly declined as the result of anthropogenic habitat alteration, such as dam construction, sand mining, and water pollution. Here, we aimed to analyze the temporal and spatial changes in biodiversity patterns of fish in Poyang Lake Basin over the last 37 years. The number of fish species underwent a significant decrease in the current period. In particular, 36.7% of the migration of fish was extirpated. Twenty‐seven fish species have been formally assessed using the Chinese Red List were currently listed as Critically Endangered (9), Endangered (3), Vulnerable (10), and Near Threatened (5). Alpha and gamma diversity revealed that fish diversity had also decreased, and beta diversity showed significant composition dissimilarity in two periods. PCoA showed that the historical fish composition dissimilarity was significantly different from that of the current period. We found a significant effect of the geographical distance on the spatial turnover component for the historical and current periods. In addition, the nestedness component was the main contributor to beta diversity, which indicated one large protected area should be established in Poyang Lake and the Ganjiang River Basin with higher species richness. These results indicated that fish biodiversity declined in the current period likely caused by anthropogenic habitat alteration and other threatened factors. Therefore, we suggest that the habitat reconstruction and biodiversity conservation for fish have become imperative in this basin, and a complete management plan should be carried out.     

Utilization of species checklist data in revealing the spatial distribution of fish diversity

Marine fish species checklists from six Chinese coastal waters were combined for the analysis of taxonomic diversity. The Genus-Family index (G-F index) ranged between 0.39 and 0.84, which generally indicated a decreasing trend with increasing latitude, with the exception of the southernmost area. Average taxonomic distinctness showed a slight increasing trend from northern to central study areas, but whether the taxonomic distinctness indices represent a latitudinal gradient of biodiversity requires further study. The multivariate analysis revealed a distinct latitudinal variation in fish assemblages. These results indicate that species checklist data are helpful in understanding the diversity distribution of fish species in the coastal zone. The potential of a species inventory should be exploited to fully understand biodiversity.