椒江口潮间带多毛类动物时空分布与环境因子的关系

为了解椒江口多毛类时空分布特征,以及自然环境变化和工业污染对其的影响程度,于2007年10月、2008年1月、4月和7月在椒江口潮间带进行底栖多毛类和环境因子调查,分析了多毛类物种数、栖息密度和生物量的时空格局以及各断面水温、泥温、沉积物结构、盐度、滩涂宽度等环境因子对多毛类时空格局的影响.结果表明:(1)在所调查的6条断面4季共发现环节动物门多毛纲动物10科20种,以广温广布种为主;(2)季节变化明显,物种数、栖息密度和生物量在春季均最高(分别为13种,31.5 ind/m2和058g/m2),秋、冬季次之,夏季最低汾别为4种,5.8 ind/m2,0.21g/m2);(3)物种数呈现位于工业区附近断面低于下游较远处的断面的趋势;(4)沉积物结构、滩涂宽度对多毛类具有显著的影响,滩涂宽度较长、沉积物较细的断面种数、栖息密度和生物量较高.     

上海市滩涂冬季底栖硅藻种类组成和生态分布

报道了上海市滩涂冬季底栖硅藻的种类组成、生态特征和数量分布情况。样品于2005年12月从7个站点中采集。经处理、镜检观察,从中鉴定出硅藻有90个分类单位,包括64种和22变种2变型(有两个未定种名),分别隶属于2纲6目9科27属。从水体咸度来看,淡水种类最多,为52个分类单位,占总数的57.78%;从温度性质来看,广温种占优势,有65个分类单位,占72.22%;从生活习性来看,底栖种占优势,有77个分类单位,占87.5%。数量分析表明,底栖硅藻细胞丰度变化为6.25×106~16.25×106cells/m2,平均为10.43×106cells/m2,在吴淞口站点含量最高。优势种为肘状针杆藻尖喙变种、斯氏布纹藻、膨胀桥弯藻和卵形双菱藻等,它们在各站点中都有分布,分别占总数的13.42%、12.56%、14.00%、9.88%。     

Demography of southern Australian bottlenose dolphins living in a protected inverse estuary

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Differential population dynamics of a coastal porpoise correspond to the fishing effort in a large estuarine system

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Relative importance of phytoplankton and periphyton on oyster-culture pens in a eutrophic tropical lagoon

The relative importance of biomass and productivity of phytoplankton and periphyton on oyster-culture pens was quantified from the tidal inlet to the inner region along a transect across a eutrophic tropical lagoon representing a gradient in flushing time over a complete seasonal cycle. Water flushing modified nutrient concentrations in the water column and the responses of phytoplankton and periphyton to nutrient enrichment. Nutrient concentrations were greater at sites in the inner region subject to poor flushing and lower at sites in the outer region subject to fast flushing. Phytoplankton chlorophyll a was greater at sites in the inner region. However, periphyton biomass decreased with increasing flushing times. Daily production rates of phytoplankton were also greater at sites in the inner region, but no significant differences in those of periphyton were observed among the study sites. On the basis of lagoon area, periphyton contributed <6% of the daily system gross production. The relative contribution of periphyton to net production was negligible when compared to that of phytoplankton. Nevertheless, there was a spatial shift in their relative contribution to the system biomass. Periphyton biomass exceeded that of phytoplankton at a well-flushed site with a large number of oyster farms available for periphyton colonization. Our results clearly demonstrate the modifying effects of tidal flushing as well as substratum area on the relative importance of periphyton biomass on oyster-culture pens in response to nutrient enrichment in coastal lagoons.     

Bottlenose dolphins (Tursiops truncatus) in the north-western Adriatic Sea: Spatial distribution and effects of trawling

1. Many species and populations of odontocetes have modified their behaviour to take advantage of feeding opportunities provided by fishing activities, with depredation of fishing gear being the most common type of adaptation.
2. The northern Adriatic Sea has been identified as an important marine mammal area because of a regular occurrence of common bottlenose dolphins. Boat surveys were conducted within a 3,000 km² sector of the Adriatic Sea off the coast of Veneto, Italy, between April and October 2018–2019. Based on 76 days at sea, 10,711 km of navigation, and 81 h 26 min of dolphin tracking, this study contributes novel quantitative information on dolphin spatial distribution, and on their occurrence in the wake of beam trawlers, otter trawlers, and midwater pair trawlers.
3. A combined generalized additive model and generalized estimation equation framework indicated that trawling—along with other physiographic, biological and anthropogenic variables—influenced dolphin distribution. In days of trawling, the chance of encountering dolphins increased by ~4.5 times (95% confidence interval 1.8–11.0) near active beam trawlers, by ~16.0 times (7.1–36.0) near otter trawlers, and by ~28.9 times (12.0–69.6) near midwater pair trawlers.
4. Spatial modelling was used to create maps of predicted distribution, suggesting differences in habitat use between trawling and no-trawling days. Spatial modelling for all days identified a dolphin distribution hotspot of 832 km², situated off the Po river delta.
5. Evidence contributed by this study can be used to inform management action within one of the world's areas most heavily impacted by fishing and other human encroachment. Such management action would help enforce the European Union's Habitats Directive and Marine Strategy Framework Directive, while also informing EU's Maritime Spatial Planning.

     

东海生态系统中鱼卵、仔稚鱼种类组成、数量分布及其与环境因素的关系

为了解当前东海生态系统中鱼卵、仔稚鱼种类组成和数量分布的现状及其变化与物理环境因素的关系,根据2006年11月—2008年6月5个航次的鱼卵、仔稚鱼和物理环境调查资料,对鱼卵、仔稚鱼种类组成、数量分布与产卵场物理环境进行分析,探讨不同季节、不同年份鱼卵、仔稚鱼种类组成和数量分布的变化及其与物理环境的关系。结果显示,5个航次采集到74 813粒鱼卵、16 826尾仔稚鱼,共有135个种类。其中,鉴定到种的有109种,隶属于15目67科99属,还有17个种类仅能鉴定到属、6个种类仅能鉴定到科和3个种类仅能鉴定到目。2006年—2007年秋季、冬季和春季鱼卵、仔稚鱼的种类和数量随着季节变化逐渐增多;2008年春季的种类和数量较2007年春季明显偏少;2008年初夏种类的数量与2008年春季基本相近,但鱼卵的数量明显增多,仔稚鱼的数量基本相近。42种优势种类、重要种类和主要种类构成当前东海生态系统中鱼卵、仔稚鱼种类组成的主要成分。东海表层水温和盐度分布有显著的季节变化。秋、冬季表层水温锋面强度最强,春季次之,初夏最弱;锋面的位置秋季离岸最近,冬季次之,春季和初夏离岸最远,冬季偏南,初夏季节北移。表层盐度锋面主要分布在近岸区域,与岸线大致平行,其强度冬季最强,春、秋季次之,初夏季节最弱。秋、冬季节陆架深水海域的水温较沿岸海域高,鱼类生殖群体在陆架深水高温区产卵;春季和初夏季节沿岸海域明显升温,鱼类生殖群体由深水区向近岸海域进行生殖洄游,产卵场分布由陆架中部向近岸海域扩展,并在近岸海域形成了中心产卵场。鱼卵和仔稚鱼的分布与温、盐锋面和种类的温、盐属性的关系密切,主要分布在温度锋面暖水一侧,并有各自最适宜的温度和盐度范围。水温、盐度与种类的繁殖生物学特性是导致鱼卵和仔稚鱼种类组成与数量发生变化的主要因素;适宜的温度和盐度范围、锋区的辐聚和卷夹作用以及种类的生物学属性是影响鱼卵和仔稚鱼数量分布以及密集分布区形成的主要因素。     

长江口中华绒螯蟹繁殖群体的组成与生理特征

为探究长江口中华绒螯蟹(Eriocheir sinensis)繁殖群体的组成及交配前后的生理特征变化,于2020年12月在长江口水域进行了调查采样。分析了中华绒螯蟹繁殖群体的规格组成、性别比例、雌蟹繁殖状态以及交配前后的肝胰腺指数(HSI)、性腺指数(GSI)和Fulton条件指数K的变化。结果显示,在长江口中华绒螯蟹繁殖群体中,雌蟹整体规格小于雄蟹,雌雄比例为0.39∶1,雄蟹数量显著大于雌蟹(χ2=101.87,P<0.05)。对生理特征的比较发现,不同繁殖状态雌蟹之间的HSI差异显著(P<0.05),其中,抱卵状态下最高,已交配状态下最低。雌蟹在已交配状态下的GSI和K指数高于未交配状态(P>0.05),抱卵状态下雌蟹的K指数最低(P<0.05)。雄蟹的GSI显著低于雌蟹(P<0.05),而K指数显著高于雌蟹(P<0.05)。雄蟹的HSI、GSI与壳宽之间呈极显著负相关(P<0.01),而雌蟹仅发现HSI与GSI之间呈极显著负相关(P<0.01)。研究结果有助于了解长江口中华绒螯蟹繁殖交配期生理特征,为中华绒螯蟹资源养护及管理提供基础数据。     

Spatial distribution of fishing effort in relation to seafloor habitats in the Kattegat,a GIS analysis

• 1. High‐resolution fishing effort data from the Kattegat, an important fishing ground for Swedish and Danish fishermen, was analysed in a Geographical Information System (GIS). Data were based on position data for individual tows reported by Swedish fishermen during 2001–2003.
• 2. Gear dimension and towing speed data were used to calculate an index for area swept per hour for each main gear type in use in the area. These indexes were multiplied by fishing effort and a grid theme of fishing intensity was created after GIS analysis.
• 3. Around 44% of the entire area was affected by Swedish fisheries during the study period, hence 56% was not affected.
• 4. Effort was highly concentrated in certain areas and 10% of the total area was covered more than twice per year.
• 5. Overlaying the effort data set with habitat maps classified according to the European Nature Information System (EUNIS) showed that the fishing pressure differed between habitats. For deep rocky and muddy habitats, almost the entire area was affected by fisheries during the study period, while both intensity and proportion affected were lower in sandy sediments and gravels.
• 6. Around 55% of the deep rocky habitats were trawled more than twice per year. Of the muddy seafloor areas, 41% were covered more than twice per year and 4% more than once a month by trawls.
• 7. The biological effects of the fishing intensities found were analysed using a database (MarLIN) containing assessments of marine habitat recoverability. All habitats except muds are probably in a nearly or fully recovered condition (as defined by MarLIN). A considerable part of the muddy habitats are in a permanently altered condition owing to fishing disturbance taking place more frequently than the indicated recovery time.
• 8. Danish fishermen report more fishing effort in the area than do Swedes. Owing to differences in reporting fishing positions, Danish fisheries could not be included in the present study. Scaling up the results to include Danish fisheries is discussed.
• 9. The results of the present study could be used to target habitat management goals more precisely, while minimizing the negative impact of restrictions on the fishing sector.
• 10. A prerequisite for performing similar studies is the availability of high‐resolution fishing effort data and high‐resolution benthic habitat maps.

Copyright © 2006 John Wiley & Sons, Ltd.     

时空及环境因子对黄河口及邻近水域斑鰶资源丰度的影响

斑(鰶)(Konosirus punctatus)作为黄河口及邻近海域近年来的优势种,其在生态系统中的作用日趋重要,为研究其资源丰度的变动对生态系统中多种生物的影响,本研究根据2013年6月、8月、10月在黄河口及邻近海域进行的渔业资源和环境调查数据,利用广义可加模型(GAM)分析了该海域夏、秋季斑(鰶)资源丰度分布特征及其与时空和环境因子的关系.结果表明,黄河口及邻近海域斑(鰶)资源丰度呈现明显的季节变化,斑(鰶)资源丰度秋季较高,夏季较低;其主要分布在黄河入海口以北的近岸海域.GAM分析表明,月份、水深、海水表层盐度和浮游植物丰度对斑(鰶)资源丰度分布具有显著影响.斑(鰶)资源丰度随浮游植物丰度的增大而增大;在10m水深范围内随水深增加呈下降趋势;一定盐度范围内,斑(鰶)资源丰度随表层盐度的增加而增大,当盐度达到17时其丰度达到最大.因此,在浮游植物丰度较高的低盐河口水域,斑(鰶)资源丰度较大,这与斑(鰶)的洄游习性、河口区受到淡水径流和海水运动共同作用所形成的环境因子的变动有关.     

Evaluation of benthic nutrient fluxes and their importance in the pelagic nutrient cycles in Suo Nada,Japan

ABSTRACT:   The benthic nutrient fluxes in Suo Nada, in the western part of Seto Inland Sea, Japan were estimated seasonally in 2002, and their contribution to the pelagic nutrient cycle was evaluated. The horizontal distributions of inorganic phosphorus (DIP), ammonia and dissolved silica (DSi) concentrations in the pore water of the surface (0–3 cm) sediments were high in the western part, indicating a eutrophic condition relative to the other parts. Seasonally, the highest nutrient concentration in the pore water was observed in summer, as reflected by the increasing decomposition rate of organic matter. Multiple regression analyses revealed significant positive effects of acid volatile sulfide (AVS) and temperature on the DIP flux and also significant positive effects of ignition loss (IL) along with these two parameters on the dissolved inorganic nitrogen (DIN) flux. Temperature, IL and redox potential (Eh) were effective on DSi. The estimated DIP, DIN and DSi fluxes from the sediments were relatively high or equivalent to the total inputs from rains and rivers in annual average, with high values in summer of 2–3-fold higher than the other sources (rain plus rivers). Thus, it is concluded that the benthic nutrient fluxes play an important role in the pelagic nutrient cycle of the Suo Nada ecosystem.     

The historical and cultural importance of ponds and small lakes in Wales,UK

1. Ponds, as sources of water, are of fundamental importance to man. However what is now regarded as a pond may have been a natural water source exploited by man at different times to meet different needs, or may have been created for a multitude of different purposes—e.g. domestic or agricultural use, for transport, defence, ritual or industrial use, social aggrandizement or the creation of the picturesque. 2. Existing natural or older man-made ponds may hold peat deposits, of great importance for palaeo-environmentalists, or may have preserved archaeological features or artefacts or environmental data which would have perished in a dry environment. 3. Modern ponds, created in suitable locations for water retention, for conservation or recreational purposes, may well be found to overlie ancient water sources. Damage may inadvertently be done to ancient structures or environmental deposits if the scheme does not take archaeological considerations into account at the planning stage. 4. The historical and cultural importance of ponds and their archaeological potential is emphasized. The vulnerability of ponds is discussed, and recommendations made for improved liaison between archaeologists and ecologists. © 1997 John Wiley & Sons, Ltd.     

秦岭黑河流域鱼类群落结构及其历史变化

秦岭黑河是西安市主要水源地, 其水生生态环境直接影响西安市乃至周边地区的社会稳定与可持续性发展。 为分析秦岭黑河鱼类群落结构特征及其历史变化, 揭示生态环境改变对鱼类群落的影响, 本研究结合历史资料和实地调查, 于 2018 年和 2019 年的 1 月、5 月、7 月和 11 月对黑河流域进行调查。研究共采集鱼类 7020 尾, 隶属 3 目 5 科 16 属 17 种, 其中鲤形目(Cypriniformes)最多, 占种类总数的 82.35%。在生态类型方面, 产黏性卵、杂食性和底栖性鱼类在黑河鱼类中占多数, 分别为总种类数的 76.47%、64.71%和 64.71%。流域中鱼类优势种为拉氏鱥 (Phoxinus lagowskii)和麦穗鱼(Pseudorasbora parva)。鱼类多样性指数范围分别为物种数(S)(12~17)、Shannon-Wiener 多样性指数(H′)(1.55~1.88)、Pielou 均匀度指数(J)(0.56~0.66)和 Margalef 丰富度指数(D)(1.54~2.15), 同时通常夏季鱼类多样性指数最高。通过聚类分析和 NMDS 分析可得, 黑河鱼类可划分为Ⅰ~Ⅲ共 3 个群落, 其中群落Ⅰ由水库生境鱼类组成, 群落Ⅱ和Ⅲ由峡谷生境鱼类组成。ABC 曲线分析显示, 不同季节中数量优势度曲线都高于生物量优势度曲线, W 统计值范围为–0.146~ –0.181, 秋季最高, 其次为冬季和春季, 夏季最低。与历史资料相比, 2010 年代和 20 世纪 80 年代的鱼类调查结果相似性指数为中等不相似(0.46)。研究结果表明, 秦岭黑河流域鱼类群落结构发生了显著变化, 推测水库建设和生境破坏是导致其变化的主要原因。     

黄河口海域春季和夏季须子网渔获物组成分析

须子网是黄河口海区应用较广的陷阱类网具之一。为养护和管理黄河口海区渔业资源,对该海域春季和夏季须子网渔获物组成进行分析。2013年5月和2014年8月对东营黄河口海区进行了3次导陷插网网具须子网的渔获物调查,采用相对重要性指数(IRI)、种类丰富度指数和Sorensen相似性系数Ss对调查数据进行了分析。结果显示,春季和夏季须子网捕获渔获物共计45种;春季和夏季渔获物优势种(IRI1 000)分别为7种和9种,共同优势种为2种;春季和夏季渔获种类的Sorensen相似性系数Ss为0.39,该海域春季和夏季的渔获物丰富度指数(R)、Shannon-Wiener多样性指数(H)、均匀度指数(J)分别为15.81和2.91、0.51和11.26、2.17和0.43;春季和夏季平均每网渔获量和尾数分别为55.04 kg和8 766尾、50.56 kg和3 390尾。调查结果表明,春季生物群落优势度较夏季优势高,使用须子网,其渔获物组成混杂、渔获幼体组成比例较高,长此以往不利于资源的繁殖保护,对黄河口渔业资源破坏较为严重。调研结果可为我国黄河口海区渔具管理以及渔业资源的可持续发展与管理提供科学参考。     

Movement of fish between a river and its backwater: diel activity and relation to environmental gradients

Abstract –  Movements of fish, in particular roach Rutilus rutilus , perch Perca fluviatilis, rudd Scardinius erythrophthalmus, bleak Alburnus alburnus and chub Leuciscus cephalus (age ≥ 1+) in relation to environmental variables were examined between the River Morava, Czech Republic, and a rehabilitated former meander. Data were taken over seven 24-h periods in April–June 1997 using two back-to-back traps. Of 170 fish captured, 70% moved from the backwater to the river. Diel activity differed between sampling dates, but overall bleak, roach and chub moved mainly between dusk and dawn, whereas perch moved throughout most of the day. Rudd showed bi-modal (mid-day, midnight) activity. However, avoidance behaviour could have biased results for species known to be wary of traps. Water level changes, temperature and illumination were among the main environmental factors influencing fish movement, along with spawning migrations relevant for most species. In all specimens, over 65% individuals captured were ready to spawn. Most of them, except for perch, were moving out of the backwater towards the river.     

2007年春、夏季黄河口海域鱼卵、仔稚鱼种类组成与数量分布

2007年春季和夏季,利用浅水Ⅰ型浮游生物水平和垂直拖网对黄河口海域鱼卵、仔稚鱼种类组成与数量分布进行了调查.春季和夏季分别设置19个(6个断面)相同的调查站位.每站表层水平拖网10min,拖网速度为2.0nmile/h;垂直拖网由底到表,拖网速度约0.5m/s.调查结果表明:春季和夏季共采集鱼卵7661粒、仔稚鱼70尾,共18种,能鉴定到种的有17种,隶属于5目12科16属,其中1种虾虎鱼类的稚鱼仅能鉴别到科的水平.优势种为斑鲦(Konosirus punctatus)、油鲟(Sphyraena pinguis)、短吻红舌鳎(Cynoglossus joyneri).春季的水平和垂直拖网分别采集6932粒鱼卵、6尾仔稚鱼和11粒鱼卵、0尾仔稚鱼.鱼卵、仔稚鱼的出现频率分别为84.21%、10.53%和15.79%、0%,平均密度分别为364.84粒/网、0.32尾,网和0.34粒/m3、0尾/m3;夏季水平和垂直拖网分别采集658粒鱼卵、57尾仔稚鱼和60粒鱼卵、7尾仔稚鱼,鱼卵、仔稚鱼的出现频率分别为84.21%、63.16%和31..58%、15.79%,平均密度分别为34.63粒/网、3尾,网和1.85粒/m3、0.22尾/m3.结果表明,黄河口海域鱼卵、仔稚鱼种类季节更替明显分成春夏季-夏季2种生态类型,种类更替率高达83.33%;河口南部海域鱼卵和仔稚鱼的群落结构相对较稳定,优势种突出,优势度较大,物种多样性水平与种间分布均匀度高于北部海域.上述规律符合该海域的水文地理学特征和硬骨鱼类的繁殖生物学规律.此外,本研究分别对春季和夏季鱼卵、仔稚鱼的数量分布以及斑鲦、油(鱼予)、短吻红舌鳎等优势种类的鱼卵数量分布绘制了密度等值分布图.与1982-1983、1984-1985、1992-1993年同期调查结果比较发现,2007年春季和夏季黄河口海域鱼卵、仔稚鱼的种类组成与数量分布发生了显著变化.分析认为,在渔业捕捞压力和环境条件变化的双重扰动下,黄河口生态系统中鱼类资源的种群交替和群落结构发生了很大变化,从而导致资源补充群体也随之改变.     

瓯江口海域夏秋季蟹类数量分布与环境的关系

本文利用2007年6月和9月瓯江口海域渔业资源调查资料,分析瓯江口蟹类资源密度的分布,及蟹类优势种、水团、水深和水文因子对蟹类数量分布的影响。结果表明,6月和9月蟹类重量密度分别为112.99 kg/km2和73.48kg/km2,尾数密度为16.84×103ind/ km2和3.80×103ind/ km2,资源总量为50845.5 kg和33066.0 kg。蟹类密度分布,在6月调查海域东部高于西部,南部高于北部,高密度区出现在瓯江口洞头群岛外侧,尤其是受台湾暖流影响明显的海域;在9月仅是南部明显高于北部,其他海域分布比较均匀。瓯江径流从瓯江北口下泄,在口外形成冲淡水水团,使瓯江口北侧蟹类密度较低。瓯江口温、盐度环境因子与蟹类重量密度负相关关系显著,与尾数密度不显著。水深与蟹类密度呈错综复杂的关系,并非线性相关关系。日本蟳（Charybdis japonica）是瓯江口蟹类最重要的优势种,三疣梭子蟹（Portunus trituberculatus）是最重要的经济品种。