不同类型虾池的理化因子及浮游植物群落的调查

于2001年10月和2002年4月两次调查分析了高位池、低位池两种类型的南美白对虾养殖池的理化因子及浮游植物群落的特征.结果表明:低位池的营养盐浓度普遍高于高位池,而高位虾池的盐度则高于低位.盐度是影响两类虾池浮游植物群落特征的主要因素.盐度较小(<5)的养殖池中,蓝藻占优势,主要为微囊藻、平裂藻、水花束丝藻、色球藻等;盐度介于10～30的池中,硅藻占优势,主要为舟形藻、桥弯藻等.     

正常与发病对虾养殖池塘浮游藻种类组成和异养细菌数量比较

通过拖网法和平板涂布细菌计数法,比较了正常与发病凡纳滨对虾养殖池塘浮游藻种类组成和异养细菌数量的差异。在四个虾池共观察到浮游藻类31属40种,它们分别属于硅藻Bacillariophyta、绿藻Chlorophyta、蓝藻Cyanophyta、甲藻Pyrrophyta、裸藻Euglenophyta、隐藻Cryptophyta和黄藻门Xanthophyta,仅二形栅藻和颤藻在四个池内都能观察到。正常池中无论是门类还是种类都超过发病池。正常池中蓝藻的含量分别为6.16%和9.77%,明显低于发病池的18.85%和43.38%。两个正常池浮游藻类的多样性指数和均匀性指数也明显高于发病池,不同池间浮游藻类群落的相似度与对虾发病与否无关。发病虾池水中的总异养菌数比正常虾池中的都高一个数量级。     

胶州湾浮游植物水华期群落结构特征

根据2001年8月对胶州湾海域进行的为期2d的大面积调查资料,对浮游植物的群落结构进行了初步研究,结果表明,浮游植物群落主要由沿岸暖水性种类组成,以硅藻为主,共34种;还有少量的甲藻7种和绿藻1种,湾中央水域出现的物种数最多,为37种;湾边缘最少,仅出现10种,细胞数量的密集区出现在湾东部边缘水域,最高值为6．96×10⁸个cell·m^-3;低值区出现在湾口,最低值仅为3．18×10⁶个cell·m^-3调查期间浮游植物的物种多样性及其均匀度的最低值均出现在湾东部边缘水域;高值区出现在湾口和湾中央水域,胶州湾海域水团运动和水体富营养化程度是影响浮游植物群落分布的主要环境因素。     

亚热带水库浮游植物群落季节变化及其影响因素分析--以汤溪水库为例

通过调查汤溪水库2003年水文、水质和浮游植物数据,分析了浮游植物群落季节变化的影响因素。结果表明,汤溪水库浮游植物丰度与群落结构具有明显季节变化。丰水期浮游植物丰度明显高于枯水期,并以7月份最高（〉10^4 cells ml^-1）。全年中,蓝藻（Cyanophyta）与硅藻（Bacillariophyta）比例变化较大,二者呈相反的变化趋势。1月份硅藻占较高比例（63.1％）,蓝藻较低（〈20％）;3、5、7月份蓝藻比例较高（分别为45．6％、55．9％、87．7％）,而硅藻较低（30．1％、25．9％、1．1％）;11月份硅藻与绿藻比例相当（各占40％）,蓝藻低于20％;12月份硅藻与蓝藻比例分别为25．6％与38．2％。3月份和丰水期浮游植物优势种主要为铜绿微囊藻（Microcystis aeruginosa）、假鱼腥藻（Pseudoanabaena）和线形粘杆藻（Gloeothece linearis）等蓝藻种类,枯水期的1月、11月和12月主要以曲壳藻类（Achnanthes）、模糊直链藻（Melosira ambigua）、颗粒直链藻（Melosira granulata）和梅尼小环藻（Cyclotella meneghiniana）等硅藻种类为优势种。枯水期营养盐可能对浮游植物生长彤成限制,但相关性分析表明,营养盐并不是汤溪水库浮游植物群落季节变化的主要影响凶素。汤溪水库全年水体较稳定,在全年范刚内水动力学对浮游植物群落季节变化没有明显影响,但丰水期5月份至7月份优势种的变化可能主要受水动力学的影响。水温与蓝藻丰度呈显著正相关,与硅藻呈显著负相关,表明水温可能是引起汤溪水库浮游植物群落季节变化的主要因素。     

绥宁河生物修复中浮游植物的生态特征研究

通过对上海市苏州河支流绥宁河治理段与非治理段水体浮游植物群落的分析,探讨了生物修复对浮游植物的影响.生物修复试验实施后治理点的浮游植物种类数比非治理点多;浮游植物细胞数、叶绿素a含量有明显下降,优势度由极度的高优势变为中度优势;Shannon-Wiener多样性指数有明显上升;治理点绿藻和硅藻种类百分比升高,并出现一些指示β中污和寡污的种类,水体浮游植物群落结构有所优化,表明水体质量有一定改善.     

大庆库里泡浮游植物群落结构及多样性研究

2012年5月—10月, 大庆库里泡浮游植物的种类组成、丰度、优势种及多样性调查研究结果表明, 库里泡共鉴定浮游植物380个分类单位(349种29变种2变型), 隶属于8门11纲22目41科104属。库里泡浮游植物群落组成主要是绿藻—硅藻型, 浮游植物种类数随季节的变化顺序为: 8月>6月>7月>5月>9月>10月。浮游植物丰度季节性变化明显, 变化范围为5.94×105—119×105 ind•L–1。浮游植物优势种不同季节间既有交叉又有演替, 优势种类大多为中营养型和中—富营养型指示种。多样性评价结果表明, 浮游动物被长期高强度捕捞后, 库里泡的浮游植物群落种类组成比较丰富, 群落结构复杂且稳定性较好, 水体处于β—中污染至轻污染水平。     

低盐潟湖秋冬交替期浮游植物群落变化与环境因子的关系

潟湖生态系统在水产养殖、旅游休闲等生态服务功能中发挥着重要作用。于2016—2018年10—12月对杭州湾北部人工潟湖的浮游植物群落以及营养盐水平进行监测,探究人工潟湖内浮游植物群落结构的变化趋势和主导这些变化的主要营养盐种类。结果表明:潟湖内浮游植物组成主要为硅藻、绿藻和蓝藻门,优势属众多,其中硅藻门的梅尼小环藻(Cyclotella meneghiniana)和变异直链藻(Melosira varians)是最常见的优势种;在调查期间Shannon指数、Margalef指数和多样性阈值等多样性指数逐年递增,水体为中度富营养化状态,水域生物多样性增加,水质维持在一二类水,水环境改善且生态风险较低;冗余分析表明,该水域秋冬交替期对浮游植物群落结构造成影响的主要环境因子为硅酸盐、水温、无机磷、氮磷比和盐度,控制该水域中无机磷的输入是防范有害藻华暴发的重要策略。     

大辽河水系夏季浮游植物群落结构特征及水质评价

作为建立中国水环境生态学基准的基础性工作,于2010年7月,按照相关规范的要求,对大辽河水系浮游植物群落结构和水质状况进行了调查.结果表明:调查期间大辽河水系共检出5门124种或变种,其中以绿藻和硅藻为主,分别占43.55％和31.45％;总细胞密度在2.05×105～1.46×107个·L-1,平均6.35×106个·L-1,绿藻和硅藻占优势;主要优势种是硅藻的颗粒直链藻极狭变种(Melosira granulata var.angustissima);共检出污染指示种44种,其中β-中污带指示种居多,有36种,占所有指示种的81.81％;Shannon多样性指数为1.43 ～2.68,Margalef指数为1.00～1.78,Pielou均匀度指数为0.52 ～0.83;综合水体中浮游植物的密度、优势种类、指示种、生物多样性指数评价表明,大辽河水系处于富营养化状态、中等程度污染水平.     

南亚热带大型贫营养水库浮游植物群落结构与季节变化——以新丰江水库为例

新丰江水库是我国第四大的水库,也是广东省最大的水库和重要的水源地。于2004～2005年2月一次调查了新丰江水库水文、水质和浮游植物分布,分析了浮游植物群落季节动态特征。新丰江水库浮游植物生物量比较低,在0．037—1．497mg&#183;L^-1之间变化。浮游植物种类较多,11次采样共检到158种。在丰度上,水库浮游植物主要以小环藻、蓝纤维藻、小球藻和纤维藻等优势种为主,而在生物量上则以微小多甲藻为优势。浮游植物组成随季节变化而不同,春季以硅藻、甲藻和绿藻为优势类群;夏季以蓝藻、绿藻和硅藻为优势类群;秋季蓝、绿藻减少而硅藻和甲藻增加。2004年的浮游植物季节性变化更为明显,有从硅藻-绿藻优势（2月和4月份）,到蓝藻-绿藻优势（6月和8月份）,到混合优势（10月份）和金藻优势（12月份）这样一个变化过程。2005年硅藻的相对丰度比2004年高出很多。两年浮游植物组成的差异与两年的降水量有关。水动力学对丰水期（6～8月份）浮游植物组成结构有较大影响,导致硅藻和绿藻相对丰度的增加。与温带贫营养型水库相比,新丰江水库的浮游植物群落具有春季和秋季种类多、夏季的蓝藻种类丰富的特点。从细胞大小分布上看,小于20μm浮游植物是生物量的主要贡献者,其次是大于45μm的浮游植物。在粒径小于20μm的浮游植物中,微小多甲藻是最主要的贡献者。浮游植物群落的大小分布受水动力学条件和营养盐浓度动态的影响。     

营养盐加富和鱼类添加对浮游植物群落演替和多样性的影响

浮游植物是水体生态系统敞水区最重要的初级生产者,其组成与多样性反映了群落的结构类型和存在状态。通过围隔实验,模拟水库春季发生的营养盐加富和鱼类放养的干扰,分析在这两种干扰下的浮游植物群落演替过程中优势种和稀有种的变化,并通过以丰度与生物量为变量的香农和辛普森多样性指数的计算,分析浮游植物群落演替过程中的多样性变化特征。结果表明,营养盐加富干扰下的浮游植物群落的优势种变化和演替更为明显,营养盐加富与鱼类添加对浮游植物群落多样性变化的影响符合中度干扰理论。在优势种优势度变化较大的浮游植物群落演替过程中,多样性指数与浮游植物生物量有较高的负相关性。在浮游植物群落演替过程中,香农和辛普森多样性指数的变化趋势基本一致,采用丰度与生物量为变量的两种多样性指数的计算结果对实验系统中浮游植物群落多样性的分析结果没有明显的影响。     

黄海山东海域春、秋季鱼类群落多样性

根据2006年春季(5月)和秋季(10月)黄海山东海域疏目变水层双拖网调查数据,作者对该海域鱼类群落多样性、空间分布及长度谱特征进行了研究。调查共捕获鱼类61种,其中鲈形目种类最多(27种),其次为鲱形目(8种)和鲉形目(7种);按摄食类型可分为浮游动物食性、浮游动物/底栖动物食性、底栖动物食性、底栖动物/游泳动物食性、游泳动物食性、杂食性、碎屑食性7个类群,其中浮游动物食性占渔获物重量组成的82.5%。春、秋季鱼类群落均主要由小型种类占优势,春季优势种有3种,为玉筋鱼(Ammodytes personatus)、鳀(Engraulis japonicus)和方氏锦鳚(Pholis fangi),秋季优势种有5种,分别是鳀、青鳞小沙丁鱼(Sardinella zunasi)、玉筋鱼、小黄鱼(Larimichthys polyactis)和赤鼻棱鳀(Thryssa kammalensis)。丰富度指数(D)、Shannon-Wiener多样性指数(H’)、均匀度指数(J’)的空间异质性明显,表现出近岸海域(尤其是青岛-乳山南部近岸海域)较高,深水区较低的态势,但多样性指数的季节间差异不显著。资源量与Shannon-Wiener多样性指数(H’)、均匀度指数(J’)、功能团多样性指数(FD)均呈负相关关系,与种类丰富度指数(D)则无相关关系。春、秋季鱼类群落长度谱曲线斜率均小于-0.2,而截距均大于10,与该海域1985年及2000年的研究结果相比,长度谱斜率显著降低、截距显著增加,这与小型个体种类占优势密切相关。与历史资料相比,黄海山东海域鱼类群落多样性下降,小型个体比例上升,资源呈衰退趋势。     

Diversity and distribution of foliose Bangiales (Rhodophyta) in West Greenland: a link between the North Atlantic and North Pacific

Greenland is a continental island in the northern part of the North Atlantic where the foliose Bangiales flora is poorly known. It is an important area for the study of algal biogeography because of the region’s glacial history, in which Greenland has been alternately exposed to or isolated from the North Pacific via the Bering Strait. A molecular study using 3′ rbcL + 5′ rbcL–S sequences was undertaken to assess the diversity of foliose Bangiales on the west coast of Greenland and rbcL sequences were used to study the Greenland flora in a larger phylogenetic and floristic context. New and historic collections document seven species in four genera from the west coast of Greenland. All species had a close link to North Pacific species, being either conspecific with them or North Atlantic–North Pacific vicariant counterparts.     

Stolidobranch ascidians from the tropical western Indian Ocean

Coastal ascidians collected over two centuries from Suez to Mozambique have been successively deposited in the MNHN and are now described and figured. Some of them were already known from the Indian Ocean, others are common to the Pacific, and some others are new species. Even though the present taxonomic work notably increases our knowledge of the tropical eastern African coast, it comprises so many miscellaneous collections from such distant points that it can only begin to suggest the diversity of ascidians there. © 2002 The Linnean Society of London. Zoological Journal of the Linnean Society , 2002, 135 , 65–120.     

不受欢迎的生物多样性：香港的外来植物物种

香港早在19世纪中叶开始就有外来植物入侵的记录,迄今为止,已发现多达238种已归化的外来或怀疑为外来的植物,其中又以薇甘菊（Mikania micrantha)、五爪金龙（Ipomoea cairica)、假臭草（Eupatorium catarium)、大黍（Panicum maximum)等最常见,外来植物最常见于受人为干扰的生境,例如荒废农田及路旁等,而较少在天然林地生境及贫瘠的灌草丛中发现,外来植物的对本地生态系统的影响主要局限于低地生境,它们常形成单优种群,减少了生境及贫瘠的灌草丛中发现,外来植物对本地生态系统的影响主要局限于低地生境,它们常形成单优种群,减少少了生境及动植物的多样性,外来动物对香港原生植物影响最大的是于20世纪70年代入侵的松树线虫（Bur-saphelenchus xylophilus)。外来的脊椎动物也有可能对香港的植物被演替产生影响,目前香港的外来植物当中,有些在大陆较少分布或没有记录,作为华南最大的港口,香港对外来物种的引入扮演着重要的角色,因此制定控制外来种在香港及华南地区的引入及传播的政策及措施非常重要。     

Presence of Palaemon Macrodactylus Rathbun 1902 (Crustacea: Decapoda: Caridea: Palaemonidae) in Mar Del Plata Harbor, Argentina: First Record from Southwestern Atlantic Waters

Adults of the palaemonid prawn Palaemon macrodactylus Rathbun, 1902 were reported for the first time from the southwestern Atlantic waters. Males and ovigerous females were collected in Mar del Plata harbor (38°03′ S; 57°31′ W), Argentina; larvae obtained from one of the collected females were reared in the laboratory until the juvenile stage. The geographical range of P. macrodactylus was previously restricted to the Pacific Ocean: it was originally described in Japan and has been reported as an invasive species in the western coast of USA in the 1950’s and in Australia in the 1970’s. Recently, this prawn has been also reported from European waters.     

Species richness of marine Bryozoa in the continental shelf and slope off Argentina (south-west Atlantic)

Abstract.  A total of 246 marine bryozoan species was recorded within an area of the south-west Atlantic between 35° and 56°S, and between the coast of Argentina and 50°W. The distribution pattern of benthic stations surveyed during the most important cruises in the area shows that the sampling effort has been biased towards southern shelf areas off Santa Cruz and Tierra del Fuego, as well as around the Malvinas (Falkland) islands. The littoral zone, Patagonian gulfs and the continental shelf off Chubut, Río Negro and Buenos Aires state received less attention, and should be surveyed more intensively in the future. Only 2% of the species can be regarded as non-indigenous, all of them inhabiting biofouling communities in harbour environments. With the exception of some thoroughly surveyed localities, the number of species recorded for different areas of the coast, shelf and slope is estimated to be just a small fraction of the actual number of species present. A distinct diversity gradient was found, with species-rich stations located only in the southern shelf. Highest diversity occurred in shelf areas dominated by coarse sediments, and along a high-productivity shelf-break front. A remarkable decrease in species richness was found in inner and middle shelf areas off Chubut, Río Negro and Buenos Aires state. This pattern may be related to the Pacific origin of the Magellanic fauna, since the diversity of bryozoans is higher in the Pacific than in the Atlantic Ocean. The trend of species richness is, however, overemphasized by the fact that the least diverse faunistic assemblage occurs in areas where surveys have been relatively less frequent. An up-to-date checklist of species recorded for the study area is included.     

Fungal assemblages associated with sponges of the southern coast of Sakhalin Island

This paper examines the biodiversity of fungi associated with six species of sponges from the southern coast of Sakhalin Island. The species richness of fungal assemblages is represented by 78 species, mainly Anamorphic fungi. The diversity and numbers of fungi depend on the species of sponge, which is due to the rigidity of the skeleton and the morphological characteristics of the sponges.     

Predation pressure shapes brain anatomy in the wild

There is remarkable diversity in brain anatomy among vertebrates and evidence is accumulating that predatory interactions are crucially important for this diversity. To test this hypothesis, we collected female guppies (Poecilia reticulata) from 16 wild populations and related their brain anatomy to several aspects of predation pressure in this ecosystem, such as the biomass of the four major predators of guppies (one prawn and three fish species), and predator diversity (number of predatory fish species in each site). We found that populations from localities with higher prawn biomass had relatively larger telencephalon size as well as larger brains. Optic tectum size was positively associated with one of the fish predator’s biomass and with overall predator diversity. However, both olfactory bulb and hypothalamus size were negatively associated with the biomass of another of the fish predators. Hence, while fish predator occurrence is associated with variation in brain anatomy, prawn occurrence is associated with variation in brain size. Our results suggest that cognitive challenges posed by local differences in predator communities may lead to changes in prey brain anatomy in the wild.     

Ecological interaction between sympatric Mytilus species on the west coast of Canada investigated using PCR markers

M. californianus is the dominant marine mussel species on exposed rocky shores, while M. trossulus is usually the dominant mussel species in more sheltered waters on the west coast of North America. Since these species are physically indistinguishable when small (< 10.0 mm), we developed two polymerase chain reaction (PCR) -based markers to discriminate between them. Using these markers, we identified mussels taken from an exposed coast ( n = 114), a sheltered harbour ( n = 80), and an upper-intertidal pool ( n = 42) on the west coast of Vancouver Island, British Columbia, Canada. M. californianus were found only on the open coast. Small M. trossulus (< 20.0 mm) were common to all three sample sites, but were extremely rare at larger sizes (> 20.0 mm) on the open coast. Our results indicate that M. californianus are excluded from sheltered waters via early life factors, while M. trossulus are excluded from the open coast due to mortality later in life.     

BIODIVERSITY RESEARCH: Genetic diversity in two introduced biofouling amphipods (Ampithoe valida & Jassa marmorata) along the Pacific North American coast: investigation into molecular identification and cryptic diversity

Aim We investigated patterns of genetic diversity among invasive populations of Ampithoe valida and Jassa marmorata from the Pacific North American coast to assess the accuracy of morphological identification and determine whether or not cryptic diversity and multiple introductions contribute to the contemporary distribution of these species in the region. Location Native range: Atlantic North American coast; Invaded range: Pacific North American coast. Methods We assessed indices of genetic diversity based on DNA sequence data from the mitochondrial cytochrome c oxidase subunit I (COI) gene, determined the distribution of COI haplotypes among populations in both the invasive and putative native ranges of A. valida and J. marmorata and reconstructed phylogenetic relationships among COI haplotypes using both maximum parsimony and Bayesian approaches. Results Phylogenetic inference indicates that inaccurate species‐level identifications by morphological criteria are common among Jassa specimens. In addition, our data reveal the presence of three well supported but previously unrecognized clades of A. valida among specimens in the north‐eastern Pacific. Different species of Jassa and different genetic lineages of Ampithoe exhibit striking disparity in geographic distribution across the region as well as substantial differences in genetic diversity indices. Main conclusions Molecular genetic methods greatly improve the accuracy and resolution of identifications for invasive benthic marine amphipods at the species level and below. Our data suggest that multiple cryptic introductions of Ampithoe have occurred in the north‐eastern Pacific and highlight uncertainty regarding the origin and invasion histories of both Jassa and Ampithoe species. Additional morphological and genetic analyses are necessary to clarify the taxonomy and native biogeography of both amphipod genera.