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1.
文章根据2016年5月、8月、11月和2017年2月在防城河口湾海域进行的渔业资源和环境调查数据, 研究了河口湾鱼类群落结构及其空间和季节变化, 分析了鱼类群落结构与主要环境因子的关系。结果表明: 全年调查共渔获鱼类95种, 隶属于2纲12目37科69属, 适温性以暖水性鱼类为主, 生态类型以底层和近底层鱼类为主。其中, 春季60种, 夏季59种, 秋季54种, 冬季46种, 夏—秋季间种类相似性指数最高。全年优势种为褐菖鲉Sebastiscus marmoratus和长鳍篮子鱼Siganus canaliculatus, 主要种有黄鳍棘鲷Acanthopagrus latus、条马鲾Equulites rivulatus、李氏?Callionymus richardsoni和真赤鲷Pagrus major等10种; 夏、秋季的最大优势种均为长鳍篮子鱼, 春、冬季的最大优势种分别为褐菖鲉和条马鲾。全湾鱼类年均资源密度为45836尾·km -2和 435.21kg·km -2, 资源密度具有明显的空间差异和季节变化。全年各站位种数变化范围在2~21种, 多样性指数H′在0.468~4.031, 丰富度指数d在0.120~1.926, 均匀度指数J在0.181~0.969。聚类分析、单因子相似性分析(ANOSIM)及相似性百分比(SIMPER) 分析表明该海域鱼类群落存在一定程度的时空异质性。相关性分析表明影响防城河口湾鱼类群落结构的主要环境因子为水温、盐度和硝酸盐。  相似文献   

2.
长江口近海春季鱼类群落结构的多样性研究   总被引:3,自引:0,他引:3       下载免费PDF全文
根据2007年5月、2008年5月和6月在长江口近海春季的底拖网调查资料,对该海域鱼类的种类组成、资源量变化、群落结构多样性及优势种类长度谱进行了分析.调查共捕获鱼类187种,带鱼在三次调查中占据绝对优势,其渔获量均占总渔获量的50%以上,其它优势种类,除小黄鱼、刺鲳、银鲳外,均为小型非经济种类.另外,冷温性的鳄齿鱼也...  相似文献   

3.
于2006—2007年5—10月间在黑龙江黑河段水域设置了六个采集点,同时进行藻类植物调查,经鉴定共发现藻类植物146个分类单位,包括110种31变种5变型,分别隶属于5门7纲15目31科57属。对藻类植物的种类组成、优势度变化及其环境相关性进行了初步分析,结果表明,黑龙江黑河江段藻类植物的群落组成表现出种类多样性丰富,群落结构复杂的特征;各采集点的藻类植物大多为淡水普生种类,有一些属于寡盐种类,中性偏弱碱性种类,还出现了一些冷水种和山区特有的种类,这些种类的出现与黑龙江黑河江段属于明显的高寒山区性河段这一地域特征相吻合。藻类植物的分布与环境因子有一定的相关性,黑龙江黑河江段pH值变化呈中性偏弱碱性,pH值年内变化趋势不明显(6.7—7.4之间),水域水温的季节变化差异显著(P0.01),呈现夏季高,春季和秋季低的现象。藻类植物的个体丰度变化受水温变化的影响显著,其分布也呈现明显的季节变化趋势。从优势种群看,黑龙江黑河段水域的藻类植物主要为贫至中营养型水体的指示种类,只在个别采样点出现少量的耐污种类,但并无向富营养化转变的趋势,说明黑龙江黑河江段整体水域环境目前无显著污染,处于贫至中营养状态。  相似文献   

4.
Regular collections of fish were obtained from the surf-zone at King's Beach, Algoa Bay. A total of 3970 fish, representing 50 species was caught with a coarse net and 16 857 fish, representing 37 species, were caught with a fine net. Predominant species were the blacktail, Diplodus sargus; the sand steenbras, Lithognathus mormyrus; the mullet, Liza richardsoni; the gorrie, Pomadasys olivaceum; the white stumpnose, Rhabdosargus globiceps; the sandshark, Rhinobatos annulatus; and the streepie, Sarpa salpa. No seasonal trends were discernible in the overall abundance or species diversity. The species composition of the dominant component of the fish assemblage varied considerably. This indicated instability in the community structure and cast doubts on the applicability of a classic community concept and the use of diversity indices. Neither classification nor correspondence analysis were of any use in identifying a characteristic species component. Multiple regression analysis indicated that short-term variations in wind conditions might be a primary determinant of fluctuations in abundance. The lack of seasonality in the community parameters may reflect the fact that short-term variability masks seasonal perturbations.  相似文献   

5.
根据2013年11月、2014年2月、5月、9月在南麂列岛国家海洋自然保护区海域进行生物资源调查所获得的资料,分析了南麂列岛海域蟹类种类组成、优势种、生物多样性等群落结构特征,并定量分析了群落结构与水文环境因子之间的关系。结果表明,周年4个季度月调查共鉴定出蟹类21种,隶属7科、12属,其中优势种为三疣梭子蟹(Portunus trituberculatus)、日本蟳(Charybdis bimaculata)和双斑蟳(Charybdis bimaculata)3种。不同季节的蟹类种类组成差异较大,而优势种类组成变化较少,其中,以秋季的蟹类种类数最多,冬季最少。从不同水深区域的渔获种类分布趋势来看,蟹类种类以20~30 m水深带较多,30~40 m水深带较少。夏季多样性指数低于其他季节,以水深来看,多样性指数在10~20 m水深带较高,30~40 m水深带较低,蟹类多样性指数与水深呈反比。根据冗余分析认为,水深、水温和盐度是影响调查海域蟹类种类组成和群落结构特征的主要环境因子。  相似文献   

6.
高公岛近岸海域浮游植物群落特征   总被引:1,自引:0,他引:1  
2009年8月对高公岛附近海域的海洋浮游植物及环境因子进行了调查,在14个调查站位共鉴定浮游植物4门36属81种,其中,硅藻门25属63种,占种数的77.78%;甲藻门9属16种,占种数的19.75%,蓝藻门1属1种,占种数的1.23%,金藻门1属1种,占种数的1.23%。浮游植物生态类型主要以低盐近岸性类群为主,辅以少量的广温广盐性类群。主要优势种为斯氏几内亚藻、短角弯角藻、拟旋链角刺藻、扭链角刺藻。优势度分别为0.688、0.207、0.142、0.103。浮游植物的细胞丰度范围为0.458×105~3.134×105个/L,平均值为1.180×105个/L。群落特征指数变幅较大(种类数为19~43,丰富度指数为1.064~2.364,多样性指数为2.069~3.428,均匀度指数为0.485~0.677)。丰富度指数均值为1.753多样性指数均值为2.926,均匀度指数均值为0.592。相关性分析表明,仅均匀度指数与水温之间具有显著的相关性,相关系数(r)为0.544,P<0.05,水温越高,均匀度指数越高;其它因子之间均没有显著的相关性。高公岛近岸海域水质状况的生物多样性指数评价显示,该海域水质总体处于轻污染,尚适宜浮游植物的生长。  相似文献   

7.
We hypothesized that temporal variation in fish species composition and community structure in a low complexity habitat in the Pueblo Viejo Lagoon, Mexico, is influenced by diel light/dark cycles and tidal stage, and by seasonal changes in salinity and temperature. We collected a total of 17,661 individuals during 2‐h interval sampling over six bi‐monthly 24‐h sampling cycles representing 53 species, of which 11 (~20%) were previously unknown in the system. Diel variation indicated that significantly higher numbers of individuals and species were caught at night, whereas diversity and evenness were higher during the day. Species richness was significantly higher in July and January, whereas diversity and evenness peaked around May; both were correlated with temperature. Diel variation in species composition was influenced primarily by the light/dark cycle. Cluster analyses of each diel cycle separated fish assemblages from midday samples from those of nocturnal samples, separated by an extended wide transition period as fish moved at dawn and during the late afternoon/dusk. Significant shifts (as determined by MANOVA) in assemblage structure occurred between months. Canonical correspondence analysis showed that temperature and day/night effects were the most important environmental variables structuring the fish community. This constrained ordination also defined species with specific habitat preferences as follows: (i) diurnal, warm temperature species (mainly planktivores) (Brevoortia gunteri, Cetengraulis edentulus, Diapterus auratus, and Membras martinica); (ii) nocturnal, warm temperature species (mainly predators) (Citharichthys spilopterus, Cathorops melanopus, and Bairdiella spp.); and (iii) low temperature, diurnal species (Brevoortia patronus and Mugil curema) or those with twilight and nocturnal distributions (Anchoa mitchilli, the most numerically abundant species). Our results indicate that diel and seasonal changes in fish community structure were mainly related to day/night cycles and temperature regimes.  相似文献   

8.
The macrofauna communities on the Dogger Bank (North Sea) from the 1920s, the 1950s and the 1980s to the 2000s were compared and identified five communities with similar spatial distribution throughout the 20th century. The abundance of dominant species in the five communities varied with time. Most obvious in the 1950s was the loss of the extensive Spisula and Mactra patches, which covered most of the shallow parts of the Bank in the 1920s. Since the 1980s, they have been found only as juveniles. The biological regime shift in the late 1980s caused an increase in macrofauna abundance, species numbers, diversity and southern species in most of the communities. The climate regime shift in 2001 had opposite effects in which the abundance, species numbers, diversity and southern species decreased in most of the communities. The increase in interface-feeding species and the decrease in sand-licking amphipods in the 2000s especially in the shallow Bank Community give evidence for climate driven changes in water masses, currents, storms, turbidity and food availability via planktonic or benthic primary production. Both fishing impact and climate change are hypothesised as explaining the changes in the Dogger Bank macrofauna communities.  相似文献   

9.
南麂列岛海洋自然保护区虾类群落结构及其多样性   总被引:2,自引:1,他引:1  
南麂列岛海洋自然保护区是国务院批准建立的我国首批5个国家级海洋自然保护区之一,素以海洋生物,特别是贝藻类生物资源丰富、种类繁多而著称,俗称"贝藻王国",也是众多渔业资源繁殖、索饵、生长的良好场所。本文根据2013年11月、2014年2、5、9月在南麂列岛海洋自然保护区开展渔业资源底拖网调查所获得的虾类资料,对南麂列岛海洋自然保护区的虾类种类组成、优势种、物种数量空间分布及多样性、相似性等群落结构特征的影响因素进行了研究。结果得知,调查海域共鉴定出虾类种类25种,隶属于9科17属,不同季节优势种更替较显著,虾类种数各季节间变化较为稳定,岛礁区的虾类种类数高于沿岸区,夏季多样性低于其他季节,虾类种类数和多样性指数平面分布相似,地形、水深和水系等环境因素对虾类群落结构影响较大;分布在南麂列岛调查海域的虾类以季节性的广温广盐性种类为主,虾类一般生活在有利于索饵、成长的泥沙底质沿岸区,夏季受台湾暖流、食物链中的鱼类捕食关系影响,其生物多样性较低,虾类多样性分布随水深变化明显,这可能主要是由于调查海域的主要优势种虾类活动范围与水深有关。  相似文献   

10.
根据2009年8月对威海港附近海域9个站位的拖网调查资料,初步分析了威海港近海底上大型底栖动物的群落结构特征,包括群落结构、种类组成、优势种、丰度和生物量、多样性等.应用PRIMIER 6.0进行了物种多样性、群落指数和ABc曲线等的分析.本次调查共采到底柄动物48种,其中甲壳动物19种,鱼类14种,各站位的大型底栖动...  相似文献   

11.
北黄海典型水域秋冬季浮游植物群落的昼夜变化   总被引:1,自引:0,他引:1  
利用冬季(2007年1月)和秋季(2007年10月)在北黄海中部昼夜连续观测所获浮游植物样品,分析了浮游植物群落的昼夜变化.结果表明:浮游植物丰度在各层存在昼夜变化,冬季10~20 m层主要在白天出现高丰度,而20~30 m层和30~底层都是在夜间出现高丰度,冬季丰度垂直分布相对较均匀.秋季各层都主要在夜间出现高丰度,丰度垂直分布是下层水体明显比上层高.2个季节优势种昼夜组成都比较稳定.冬季优势种为具槽帕拉藻(Paralia sulcata),主要分布在下层水体.秋季罗氏角毛藻(Chaetoceros lauderi)和密连角毛藻(Chaetoceros densus)成为优势种,两者分别以下层和上层水体分布较多.冬季浮游植物群落多样性和均匀度昼夜变化都不明显,秋季0~10 m层和20~30 m层多样性和均匀度昼夜变化较明显.从季节变化来看,秋季多样性要高于冬季,均匀度的季节变化不明显.  相似文献   

12.
One hundred and eight fish species were collected between March 2003 and February 2004 from 11 study sites in Pattani Bay, southern Gulf of Thailand. The catches consisted primarily of juveniles or adults of small-sized fishes, indicating that the bay was important as nursery ground for fishes. Of the 43 families, Leiognathidae (43.3% contribution), Centropomidae (15.2%), Siganidae (13.8%), Engraulidae (10.3%), Atheriniidae (6.9%), Clupeidae (4.8%) and Ariidae (3.1%) were dominant in the catch. Significant differences were found in relative abundance and species richness between both sampling sites and months. The sampling sites were clearly defined by fish community into four different habitats that were directly related with the bottom structure of each site. The 30 most dominant fish species were categorized according to habitat preference into five different groups. Some species exhibited preference for specific habitats, whereas others were distributed throughout the bay. Seasonally, fish community structure revealed four different recruitment and occurrence periods, which were February to April, May to September, October and November to January, which was partially related to local monsoonal seasons. Analysis of the 30 most dominant fish species demonstrated that they were clustered into six different seasonal groups, with some showing a clear preference for specific months, although many recruited and occurred throughout the year. Results of this study help to clarify the ranges of habitats, months and seasons used by a number of fish species found in tropical coastal habitat.  相似文献   

13.
2001—2002年粤东柘林湾浮游动物的生态学研究   总被引:25,自引:3,他引:25  
2001年4月-2002年4月,利用生态学方法对粤东柘林湾浮游动物进行的周年调查结果表明,粤东柘林湾浮游动物有桡足类34属60种,枝角类3属3种,及端足类、磷虾、糠虾、多毛类、毛颚类、被囊类、水母和各种浮游幼体虫.浮游动物的群落构成小型化趋势明显,因为体长不足0.6 mm的小型优势种强额拟哲水蚤(Paracalanus crassirostris)、短角长腹剑水蚤(Oithona brevicornis)和鸟喙尖头(氵蚤)(Penilia avirostris)在浮游动物总个体数中所占比例合计高达57.1 %.浮游动物的种类数、总个体数和生物量的平面分布模式大体相似,即湾外大于湾内,外侧大于内侧,东部大于西部.总个体数与生物量的周年变化曲线与水温的变化趋势非常相似,高峰位于高温季节的8-9月,低谷位于冬季2月.调查期间柘林湾浮游动物非常丰富,年均总个体数达15.8×103 ind/m3,生物量达227.8mg*dW/m3.在单一调查年度内,浮游动物丰度与水温、浮游植物细胞数呈显著正相关关系.在不同年份,浮游动物丰度与浮游植物密度则表现为负相关的趋势.  相似文献   

14.
南宁邕江网箱养殖区浮游生物种群结构特征   总被引:1,自引:0,他引:1  
浮游生物是评价水体质量的一项重要生物指标,为了解广西南宁邕江网箱养殖区的水质状况,于2009年9月-2010年9月在金陵至清川桥江段网箱养殖区设置2个监测断面,每两个月采样1次,对其水质和浮游植物种群组成、密度和优势种变化进行了系统研究.结果表明:邕江网箱养殖区共检出浮游植物8门98属(种),绿藻、硅藻分别占浮游植物总种数的42.8%、24.5%;共检出浮游动物4大类44属(种),优势种为轮虫类,占浮游动物总种数的43.2%.总体看来,邕江网箱养殖区浮游生物种数夏秋季节多,冬春季节少;浮游生物密度与种数季节变化趋势一致.邕江网箱养殖区综合营养状态指数(TLI)介于59.28-66.87之间,属于中度富营养化水平.Shannon-Wiener多样性及均匀度指数分别介于1.35-1.56和0.2275-0.2586之间,表明邕江网箱养殖区在监测期内处于中营养—富营养状态,这与采用相关加权综合营养状态指数法的评价结果一致.  相似文献   

15.
The results of a study performed before and after the discharge of an ocean outfall off Mõkapu Point, Oahu, Hawaii, from 1975 to 1979 show large increases in the number of species and abundance of fish around the outfall site. The construction of the outfall afforded new rock substratum for the attachment of algae and sessile animals which attracted large aggregations of fish. During a 112 year period there were no significant community structure 1–5 km from the outfall when measured by similarity indices. No significant changes in algal biomass occurred between samplings.Similarity indices may be better indicators of fish community change than diversity indices since the former reflect changes in the relative abundance of species in common and large temporal changes in a community structure may occur without changing the value of its diversity index. Morisita's (1959) similarity index has greater sensitivity to the changes in fish community structure than the index derived by Sorensen (1954) due to emphasis on the relative abundance of dominant species.  相似文献   

16.
海州湾南部海域不同季节虾类数量及其分布特征   总被引:3,自引:0,他引:3  
根据2009年5月、9月和12月对海州湾南部海域3个航次的渔业资源调查资料,对该海域十足目虾类的数量和分布的特征进行了初步研究,且探讨了优势种、温度、盐度、水深等因素对以上特征的影响。结果表明,5月虾类资源量最高,9月最低,12月较9月有所回升,分别以戴氏赤虾Metapenaeopsis dalei和日本鼓虾Alpheus japonicus、细巧仿对虾Parapenaeopsis tenella和刀额新对虾Metapenaeus ensis、日本鼓虾等为主要优势种。5月和9月虾类平面分布趋势均为西北外侧和东南水域较低,南面沿岸较均匀,东部和中部出现最高值;12月北面和南面近岸资源量较低,其他水域较均匀,最高值出现在东部水域。逐步回归分析表明,海州湾虾类资源量与底盐间存在显著相关关系,其他水文因素无显著相关关系。此外,优势种生态习性、赤潮和径流等是影响海州湾虾类数量和分布变化的主要因素。  相似文献   

17.
Peracarids (Crustacea: Peracarida) are an important component of soft-sediment faunas and are considered good indicators of quality of water and sediments. Nevertheless, little is known about diversity of peracarid crustaceans on the shallow subtidal sediments of Playa América, a sandy beach in the Ensenada de Baiona (Galicia, NW Spain). Therefore, the peracarid fauna of its shallow subtidal zone was studied in a fine-sand site at 4-m depth from February 1996 to February 1997. Monthly sampling yielded a total of 4753 individuals belonging to 60 species. Amphipods were dominant in number of individuals and species followed by cumaceans. The assemblage showed a stable composition in species through the year and was numerically dominated by a few species, namely the amphipods Siphonoecetes kroyeranus and Microprotopus maculatus and the cumacean Pseudocuma longicorne . These species showed large monthly fluctuations in abundance, with maximal values between summer and autumn.  相似文献   

18.
The test panels have been set for one year in the waters of Daguanban reclamation area of Luoyuan Bay to investigate the ecology of fouling community. 39 species of animals and 8 species of algae have been recorded during the investigation. The main period of settlement extends from May to October. The peak periods of biomass and covered area rate of the panels have been observed from Juneto September Balanus reticulatus, Bugula neritina, Molgula manhattensis, Tubularia mesembryanthemun and Enteromopha interstinalis are the dominant species in the fouling community. Species diversity index, species richness, species evenness and environmental factors are determined, the results of which indicate that water flow speed is the most important factor influencing the species and quantity composition of the fouling community.As to the mariculture production in the reclamation area, the main harmful period ranges from June to September.  相似文献   

19.
Twice monthly sampling over two 16 month periods at a shallow site on Newfoundland's east coast showed the fish assemblage to be dominated by four taxa (Gasterosteus aculeatus, G. wheatlandi, Osmerus mordax, Gadus spp.) that accounted for 96% of the individuals collected. Of the 16 479 fish measured, 65% were adults based on the estimated size of first spawning. The fish assemblage was dominated (86%) by species with demersal eggs, several of which spawn at the same shallow sites used by juveniles as nursery sites. Coastal spawning and demersal eggs maintain offspring in coastal nursery areas where survival is thought to be increased. Number of species and number of fish were both correlated with water temperature being highest from mid-summer to early autumn and lowest in winter. Temperature, time of spawning, and movements of juveniles and adults facilitated grouping species into five assemblages based on seasonal abundance: seasonal periodic species (summer and winter), regular species, regular species collected in all seasons except winter, and occasional (rare) species. At the diel scale, two consistent species groupings were observed: species that showed no significant difference between day and night and species caught primarily at night. Number of night species exceeded day species by a factor of two. No seine-caught species in shallow water exhibited significantly higher catches during the day. Observations by SCUBA divers indicated some species were more abundant during day time at slightly deeper depths. This observation in conjunction with day and night seining in shallower water, suggests these species aggregate in deeper water during day and move to shallow waters at night.  相似文献   

20.
Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery. As the fifth largest river estuary in the world, the Huanghe (Yellow) River estuary (HRE) is a typical estuary that has been seriously aff ected by human activities. Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated infl uencing factors. A total of 23 and 20 species of eggs and larvae, respectively, were collected. The dominant orders were Perciformes (51.2%) and Clupeiformes (25.6%). The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m^3 , respectively. The dominant species were mainly low-commercial-value small-sized fishes, such as Clupanodon punctatus , Harengula zunasi, and Acanthogobius, whereas certain traditional commercial fishes, such as Trichiurus lepturus , and Clupea pallasii, were not seen. Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages. Salinity was the main factor on the spatial distribution of ichthyoplankton communities, the species number and Shannon-Weiner diversity index (H′) of the fish egg and larval community near the river mouth with lower salinity were signifi cantly lower than the community far away from the river mouth with higher salinity. In addition, increases of water temperature promoted the number and abundance of fish species eggs, and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species. In overall, overfishing, dam construction, and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE.  相似文献   

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