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1.
滆湖鱼类群落时空分布及其与环境因子的关系   总被引:1,自引:0,他引:1  
为掌握滆湖鱼类群落现状及动态,于2017—2018年在该湖设置16个采样点,使用多网目刺网和地笼对鱼类群落进行了周年季度采样,同时测定各采样点的水温(WT)、水深(WD)、透明度(SD)、pH值、叶绿素a(Chl.a)、总氮(TN)和总磷(TP)等环境因子,定量分析了鱼类群落结构特征、时空分布格局及其与环境因子的关系....  相似文献   

2.
兴化湾海域鱼类多样性的时空变化   总被引:3,自引:0,他引:3  
利用2009年1月、2008年4月和9月兴化湾海域(位于福建省沿海中段)鱼类学调查资料,研究兴化湾海域鱼类种类组成、种类数和多样性的时空分布,探索当地地形、地貌、水文环境等因素对鱼类多样性的影响.结果表明,在3次调查中,共鉴定鱼类123种,其中1月47种、4月48种和9月81种.鲈形目种类有51个,占总种类数的41.46%.1月、4月和9月,鱼类质量H值分别为2.59,1.78和2.65,尾数H值分别为2.84,2.42和2.42,其中质量H值的季节变化特征与种类数相同,而尾数H值冬季最高.1月鱼类的尾数多样性仅与种类数相关(r=0.69,P=0.0145);4月尾数H仅与尾数密度相关(r=0.62,P=0.023 8),9月尾数多样性与种类数和尾数密度均不相关,显示出1月的种类数,4月尾数密度分别是影响鱼类多样性分布的主要因素.种类季节更替率从1月到4月为79.75%.从4月到9月为82.41%.从9月到次年1月为77.88%.兴化湾内湾潮滩地形和径流,不同潮流在中湾交汇,洄游性鱼类去留是影响兴化湾海域鱼类种类和多样性分布的主要因素.  相似文献   

3.
Abstract  The fish fauna and habitat characteristics in five reaches of a small lowland stream were studied through the summer and winter of one year. All species densities, except Atlantic salmon, Salmo salar L., were correlated with either instream or outstream cover, reaffirming the importance of cover to maintain the local abundance of fish populations. There were significant differences between reaches in the density of all the fish species studied, with the exception of the larger size group of dace. Leuciscus leuciscus (L.), and between sampling times for salmon, dace and eel, Anguilla anguilla (L.). There were significant differences between reaches for all the measured habitat variables apart from instream cover, and between sampling times for velocity. instream cover, and substrate particle size, but not depth, width:depth ratio and outstream cover. The implications of these variations for fish stock assessment and predictive fish habitat models such as PHABSIM and habitat suitability indices are discussed.  相似文献   

4.
2018年8月15-19日,利用Lowrance elite-7 Ti回声探测仪首次对云南省泸沽湖展开鱼类空间分布及资源量评估。调查采用"之"字形航线对泸沽湖全湖进行水声学探测,累计航程42.71 km,基于深度变化值将探测水体分为若干探测单元进行鱼类资源评估,并运用反距离插值法(IDW)基于各单元密度绘制进行空间分布图。水声学探测结果表明,泸沽湖鱼类空间分布不均匀,水平方向上,鱼类主要集群分布于近岸环形水域,其中小渔坝附近水域鱼类密度最高,湖心区域鱼类密度最低;垂直方向上,鱼类在表层水域分布较为集中;2018年8月泸沽湖鱼类密度为0.153尾·(1000 m^3)^-1,数量24.39万尾,总资源量50.55 t;其中,鲫(Carassius auratus)21.17万尾、17.36 t,鲤(Cyprinus carpio)1.74万尾、23.01 t,草鱼(Ctenopharyngodon idellus)8.63万尾、8.63 t,大鳞副泥鳅(Paramisgurnus dabryanus)0.68万尾、1.33 t,小口裂腹鱼(Schizothorax microstomus)0.07万尾、0.22 t。此次调查未发现曾出现记录的宁蒗裂腹鱼(S.ninglangensis)和厚唇裂腹鱼(S.labrosus)。  相似文献   

5.
Abstract – We sampled three limnetic fish species: juvenile sockeye salmon (Oncorhynchus nerka), three‐spine stickleback (Gasterosteus aculeatus) and longfin smelt (Spirinchus thaleichthys) in Lake Washington to quantify species‐specific patterns of diel vertical migration (DVM). Catch‐per‐unit‐effort data analysed from 15 years of midwater trawling documented seasonal and diel differences in vertical distributions for each species. These results were consistent with the hypothesis that the patterns of DVM in Lake Washington were affected by life history, size and morphology. Sockeye salmon showed clear DVM in spring but essentially no DVM in fall, remaining in deep water, whereas three‐spine sticklebacks were prevalent at the surface at night in both seasons. In fall, distribution patterns may be explained by differences in thermal performance (e.g., sticklebacks favouring warm water), but the patterns were also consistent with inter‐specific differences in predation risk. Younger sockeye salmon and longfin smelt were present in greater proportions higher in the water column during dusk and night periods than older conspecifics. Compared with sockeye salmon, the greater use by three‐spine sticklebacks of surface waters throughout the diel cycle during weak thermal stratification in spring was consistent with the hypothesis that sticklebacks’ armour reduces predation risk, but use of this warmer, metabolically beneficial stratum may also have promoted growth. This study illustrates variation in the vertical distribution of three sympatric planktivores and offers broader implications for the DVM phenomenon and applied lake ecology.  相似文献   

6.
费骥慧  汪兴中  邵晓阳 《水产学报》2012,36(8):1225-1233
根据2009年8—11月对洱海鱼类调查获得的有关资料,研究了洱海鱼类群落的空间分布格局,旨在为洱海鱼类资源的保护和利用提供有价值的资料。研究结果表明:洱海鱼类群落可分为3种群落类型,分别为洱海西岸与南北端湖滨带群落类型(群落Ⅰ)、东岸与湖心区群落类型(群落Ⅱ)和上游小型湖泊群落类型(群落Ⅲ)。群落Ⅰ的主要特征种为(Hemiculterleucisculus)、鲫(Carassius auratus)、麦穗鱼(Pseudorasbora parva)、黄(Hypseleotris swin-honis)、子陵栉虎鱼(Ctenogobius giurinus),对群落内平均相似性贡献率为80.71%。群落Ⅱ的主要特征种为鳙(Aristichthys nobilis)、鲢(Hypophthalmichthys molitrix)、团头鲂(Megalobrama amblycephala)、草鱼(Ctenopharyngodon idella)、鲤(Cyprinus carpio),对群落内平均相似性贡献率为98.20%。群落Ⅲ的主要特征种为鲫、麦穗鱼、长身(Acheilognathuselongatus)、棒花鱼(Abbottina rivularis)、中华鳑鲏(Oryzias latipes sinensis)、子陵栉虎鱼等,对群落内平均相似性贡献率为94.94%。群落Ⅰ和群落Ⅲ在种类和数量组成上以小型鱼类为主,群落Ⅱ则以大中型鱼类为主,鱼类群落在空间分布上的环境差异明显。  相似文献   

7.
Temporal variation in Lake Balaton and its fish populations   总被引:4,自引:1,他引:3  
Abstract— Dramatic changes have occurred in Lake Balaton in the last 40–45 years. Variations in water quality have resulted in a decrease in fish and invertebrate diversity. Fish assemblages have changed in response to human-induced eutrophication, environmental perturbations, introduction of exotic fish species, over-fishing and species-habitat interactions. Fish biomass and productivity first increased during the early 1970s with enhanced primary production, then decreased with the reduction of exploitation since the late 1970s and induced intra- and interspecific competition. Previous stable populations began to oscillate, and the majority of stocks became fragile by the mid-1980s. Extinction of native fish and invasion of new alien species alternate. Alien species have transformed the food webs, causing long-lasting ecological changes. Reduced and non-selective exploitation has resulted in higher fish density and lower production rates. Recent studies have revealed differences in the carrying capacity of fish between the littoral zone and the open water areas.  相似文献   

8.
Spatial and temporal patterns in fish communities along the Illinois River   总被引:1,自引:0,他引:1  
Abstract –  Fish abundance data from a fish population study (1957–2000) on the Illinois River, IL, USA were used to assess community structure. There was considerable variability among reaches and years, but three distinct fish communities were identified encompassing both temporal and spatial aspects. Temporal community shifts in the upper half of the river created two distinct fish communities, one prior to 1983 and the other after 1983. This is believed to be in response to improved water quality, albeit the responses were delayed for several years after policy implementation. The third group (Lower River) was spatially separated from the two upper river groups. These differences may reflect a combination of water quality (e.g., pollution) and habitat issues (e.g., geomorphology), common to many regulated rivers. Fish community responses in larger rivers may have considerable temporal lags after implementation of management or restoration activities that warrant strong consideration during any planning process.  相似文献   

9.
Historically, yellow perch, Perca flavescens Mitchill held great recreational and commercial importance to the Lake Michigan fishery. Unfortunately, fluctuations in lake‐wide abundances in the past four decades created inconsistencies in catch. As adults, yellow perch have been commonly observed to swim great distances suggesting there is likely to be partitioning of the population within the lake. The objective was to determine whether population demographics of yellow perch in the Indiana waters of Lake Michigan were consistent with a single population. Seasonal population demographics of yellow perch collected from the Indiana waters of Lake Michigan in 2009, 2011 and 2012 were compared. Catch‐per‐unit‐effort of female yellow perch increased during later sampling periods across years. Similarly, total length of females and males increased 10% throughout the year. The proportion of females increased from 20% at the beginning of the survey period to 95% at the end. A few larval yellow perch were collected. These data suggest that Indiana waters of Lake Michigan are not a primary spawning area, rather these waters serve as a feeding or recovery area for post‐spawned yellow perch, particularly females.  相似文献   

10.
The small pelagic cyprinid, Rastrineobola argentea (Pellegrin), commonly known as dagaa, accounted for 60% of the total fish biomass and 40% of the commercial catches in Lake Victoria in 2015. However, some aspects of the biology of species (from which management interventions are based) have changed since 1970s; and yet harvest regulations have remained the same. In this study, spatial and temporal variations in life history traits of dagaa in the northern portion of Lake Victoria were examined in relation to fishing intensity to offer guidance on possible adjustments in managing the fishery. The mean standard length halved, whilst the length at 50% maturity (Lm50) reduced by 27%, between the 1970s and 2015; however, the decline in Lm50 was more pronounced in males than females. Data collected between 2014 and 2015 showed that immature individuals are largely harvested from inshore and mid‐island areas, whilst most of the fishes caught in open water areas are largely mature irrespective of the size of the gear used. The causes of the changes in these biological aspects, and the need for policy adjustment, are discussed in the context of changes in fishing pressure.  相似文献   

11.
长江中游监利江段鱼卵及仔稚鱼时空分布   总被引:3,自引:0,他引:3  
2010年5-7月对长江中游监利江段鱼卵和仔稚鱼的时空分布进行调查,共采集到鱼卵样品9494粒,仔稚鱼样品328422尾,分属8目15科43属51种.结果显示:5-7月鱼卵的平均密度为13.3 ind./100m3,最大密度值87.8 ind./100 m3,主要集中在5月;5-7月仔稚鱼平均密度为61.8 ind./...  相似文献   

12.
珠江口鱼类群落结构的时空变化   总被引:6,自引:1,他引:6  
王迪  林昭进 《南方水产》2006,2(4):37-45
根据1986~1987年珠江口及其邻近水域渔业资源的周年月份调查数据,运用MVSP软件包中的聚类分析和主坐标分析对珠江口鱼类群落的时空变化进行定量分析,描述珠江口鱼类群落的季节变化和区域变化特征,把珠江口从时空上划分为4个季节和5个水域,并与传统的划分方法作比较,讨论了这种分析结果的合理性。综合考虑个体数、重量、出现频率等因素,把珠江口鱼类的优势种确定为优势度大于1000的丽叶鲹、棘头梅童鱼、凤鲚、银鲳、杜氏棱鳀、带鱼、黄斑鲾和赤鼻棱鳀等8种,分析了优势种的区域和季节变化。  相似文献   

13.
红枫湖鱼类资源及空间分布的水声学调查研究   总被引:1,自引:0,他引:1  
于2010年9月~12月和2011年3月~6月对贵阳市红枫湖的鱼类资源进行了调查,捕获鱼类28种,分属于4目6科;鱼类的体长为5.68~116.41 cm,优势体长组为11.00~30.00 cm,其中小型鱼体和中大型鱼体占多数。2011年6月运用BioSonics DT-X(200 kHz)鱼探仪对鱼类密度进行了水声学探测,平均密度为(51.64±36.49)×10-3尾.m-3,不同区域的鱼类密度分布有显著性差异,最大值出现在将军湾[(97.25±12.35)×10-3尾.m-3],最低值位于红枫湖大坝[(14.90±2.56)×10-3尾.m-3],从大坝到将军湾鱼类资源量总体上呈现逐步增长的趋势。红枫湖鱼类分布水层主要在6~15 m,不同水层的鱼类密度分布存在显著差异。  相似文献   

14.
鄱阳湖湖口鱼类资源现状调查   总被引:2,自引:0,他引:2  
2014年5月-12月对鄱阳湖湖口县水域鱼类资源进行逐月调查,对该水域鱼类种类组成、渔获物结构、优势种、群落多样性指数和单位捕捞努力量渔获量(CPUE)进行分析。结果显示,在鄱阳湖湖口水域共采集鱼类52种,隶属于7目12科40属;优势种分别为鲤(Cyprinus carpio)、鲢(Hypophthalmichthys molitrix)、鲫(Carassius auratus)、鳙(Aristichys nobilis)和光泽黄颡鱼(Pelteobagrus nitidus),占样本个体总数的61.34%;Shannon-Wiener多样性指数(Hi)为2.59,Margalef种类丰富度指数(D)为6.09,Pielou均匀度指数(J')为0.65,Simpson优势度指数(λ)为0.87,相对稀有种数(R)为97.87%;该水域定置网CPUE为1.10~6.21 kg/d,与湖口水位呈显著正相关(P0.05)。鄱阳湖湖口水域渔业捕捞个体以小型鱼类居多,洄游型鱼类的幼鱼补充群体数量极少,鱼类群落多样性指数有上升趋势。  相似文献   

15.
刘勇  程家骅  张寒野 《海洋渔业》2022,44(6):790-801
帆式张网因其作业成本低、效率高、机动灵活等优点,成为江苏省海洋渔业的重要渔具之一,但因其对幼鱼资源的极大破坏,受到严格管控和限制。基于2014年江苏沿海帆式张网渔船的大样本随机抽样调查数据,对日产量及渔获物结构与渔场时空分布进行了分析。结果显示:江苏省帆式张网渔船生产水域相对集中于大沙渔场,个别月份会根据渔业资源变动,向南部、外海或近岸水域进行渔场拓展。渔船分布相对集中的水域,水深范围为30~50 m,所占比例超过50%。渔场范围在东西方向与南北方向的跨度呈此消彼长关系;渔船作业所覆盖的渔区数量与平均日产量之间存在负相关,当产量高时相对集中,产量低时相对分散。渔获组成随季节发生一定的变化,主捕经济鱼种资源时空变化是影响帆式张网渔场变动的主要原因。冬季和春季,帆式张网以小型中上层鱼类、小型虾类和经济鱼类幼鱼为主要捕捞对象;秋季,则以带鱼(Trichiurus haumela)、小黄鱼(Pseudosciaena polyactis)和三疣梭子蟹(Portunus trituberculatus)等经济鱼种作为主捕对象。帆式张网作业对经济幼鱼的破坏严重,应进一步加强网囊网目尺寸的严格管理,...  相似文献   

16.
长江芜湖江段鱼类多样性及其群落结构的时空格局   总被引:4,自引:0,他引:4  
为制定合理的渔业资源保护措施与管理对策,2009年按季度共4次调查了长江芜湖江段鱼类多样性及其群落结构。结果显示:该江段现有鱼类54种,其中以似鳊(Parabramis pekinensis)、油(Hemiculter bleekeri bleek-eri warpacho)、短颌鲚(Coilia brachygnathus Kreyenberg et Pappenheim)、鲫(Carassius auratus)等中小型鱼类为常见种和优势种,表明了该江段的鱼类组成存在明显的小型化特点。长江干流沿岸浅水区的鱼类多样性最高,江心深水区最低,而青弋江支流、漳河支流和漳河河口的居中,青弋江的鱼类种数和个体数都显著低于沿岸浅水区,但漳河的鱼类数量与沿岸浅水区无明显差异。江心深水区的鱼类群落与其它样点明显不同,而青弋江的鱼类群落与沿岸浅水区、漳河及其河口的鱼类群落也存在部分差异。鱼类群落结构的季节动态无显著性。  相似文献   

17.
本研究旨在通过水声学方法评估博斯腾湖鱼类的季节和空间分布特征,掌握鱼类群落结构和时空分布规律。于2019年4—10月使用分裂波束回声鱼探仪(Simrad EY60, 120 kHz)进行全湖走航式断面探测,定量分析了鱼类密度、大小组成(以目标强度衡量)、水平和垂直分布的时空变化。研究结果显示,博斯腾湖春季、夏季和秋季鱼类密度分别为(709±141) ind/hm2、(8783±2611) ind/hm2和(743±499) ind/hm2,平均目标强度分别为–52.95 dB、–59.91 dB和–57.73dB。水平方向上,春季和秋季鱼类主要分布于沿岸带和敞水区,夏季鱼类更多地分布在沿岸带和水草生长区域。垂直方向上, 3个季节鱼类密度在水深3 m以下均随水深逐渐减小。目标强度在春季和秋季均呈现随水深逐渐增加趋势;夏季在水深3~12m之间随水深逐渐增大,但在大于12m水深区域有所减小。推测博斯腾湖鱼类群落的时空动态与繁殖、生长和捕捞等因素有关。本研究为保护和合理利用博斯腾湖鱼类资源提供了重要的基础资料,同时也为认识该湖生态系统提供了科学依据。  相似文献   

18.
For understanding the reproductive dynamics of fish assemblages and their relationship with environmental conditions, we need to know more about spawning areas and periods. Studies on temporal and spatial patterns of occurrence of fish eggs and larvae are important for obtaining this kind of information quickly and accurately. In this study, we analysed spatial and temporal patterns of fish larvae in different biotopes in a stretch of the floodplain of Upper Parana River, in Ilha Grande National Park, southern Brazil. We carried out night sampling during six spawning periods, from 2001 to 2008. We selected 18 sampling sites distributed in the mainstream, tributaries and lagoons, encompassing several types of biotopes. We observed significant spatial and temporal differences among biotopes in the composition and structure of the fish larvae assemblages. Lentic environments favoured the development of sedentary and migratory species, whereas tributaries were used as migratory routes and spawning areas. The assemblage in period I differed from the assemblages of other periods, probably because of the presence of dams in the Parana River. No association was observed between environmental variables and spatial and temporal patterns of the ichthyoplankton assemblages. Hence, conservation measures are essential to maintain the environmental integrity of spawning (tributaries) and development areas (lagoons) for the maintenance of biodiversity in the floodplain of Upper Paraná River.  相似文献   

19.
基于稳定同位素技术的阳澄湖鱼类群落营养结构研究   总被引:1,自引:0,他引:1  
为探究阳澄湖水域鱼类群落的营养结构特征, 于 2017 年夏季(7 月)、秋季(10 月)、2018 年春季(4 月)对该水域进行了渔业资源调查, 并利用稳定同位素技术对鱼类群落的碳(δ13C)、氮(δ15N)值特征及其营养结构进行了分析。 研究结果显示, 阳澄湖水域共采集到鱼类 42 种, 隶属于 5 目 10 科 33 属。鱼类的 δ13C、δ15N 和营养级均值分别为 (–24.85±1.77)‰、(15.34±2.19)‰和 3.06±0.64。其中, δ15N 值与营养级均存在极显著的鱼类食性和季节性差异(P< 0.01), 而 δ13C 值在鱼类食性和季节性上未出现显著差异(P>0.05)。阳澄湖鱼类群落的营养结构存在季节差异, 鱼类群落的营养层次(NR)、基础食物来源(CR)、生态位总空间(TA)、群落的整体密度(NND)、聚集均匀程度(SDNND) 和核心生态位空间(SEAc)从 2017 年夏季至秋季再到 2018 年春季, 呈逐渐上升的趋势; 表明 2018 年春季食物源多样性高, 营养冗余程度低。本研究初步构建了阳澄湖鱼类连续营养谱, 丰富了对阳澄湖鱼类群落营养结构方面的研究, 以期为湖泊生态管理和渔业可持续发展提供参考。  相似文献   

20.
Abstract– Four locations (i. e., mouth, lower midreach, upper midreach, and headwater) were sampled bimonthly for two years in a Kansas, Flint Hills stream. Principal components 1 (PC1; depth, width, substrate) and 2 (PC2; velocity, water temperature, conductivity) accounted for 70% of the variation in habitat variables. Principal component 1 varied more spatially than temporally, and PC2 exhibited the opposite pattern. Species diversity varied spatially with the highest values at the upper midreach and mouth and lowest in the headwaters. Species diversity also varied temporally with highest values in summer months and lowest in late fall and carly spring. Catch per unit effort (C/f) varied temporally and spatially by trophic guilds and species. In general, C/f values were highest in late fall and early spring and were lowest in early and mid summer. Fixed spatial variation (i. e., spatial difference independent of temporal factors) was higher than ephemeral spatial variation (i. e., spatial variation that varies temporally) for species with specialized feeding habits. Conversely, ephemeral spatial variation was highest for fish species with generalized feeding habits. These data indicate that standardizing reaches and dates are important if habitat, species diversity, and C/f data will be used in managing stream ecosystems.  相似文献   

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