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31.
A significant expansion of offshore wind power is expected in the near future, with thousands of turbines in coastal waters, and various aspects of how this may influence the coastal ecology including disturbance effects from noise, shadows, electromagnetic fields, and changed hydrological conditions are accordingly of concern. Further, wind power plants constitute habitats for a number of organisms, and may locally alter assemblage composition and biomass of invertebrates, algae and fish. In this study, fouling assemblages on offshore wind turbines were compared to adjacent hard substrate. Influences of the structures on the seabed were also investigated. The turbines differed significantly from adjacent boulders in terms of assemblage composition of epibiota and motile invertebrates. Species number and Shannon–Wiener diversity were, also, significantly lower on the wind power plants. It was also indicated that the turbines might have affected assemblages of invertebrates and algae on adjacent boulders. Off shore wind power plant offer atypical substrates for fouling assemblages in terms of orientation, depth range, structure, and surface texture. Some potential ecological implications of the addition of these non-natural habitats for coastal ecology are discussed.  相似文献   
32.
台湾省两个港湾污损生物初步研究   总被引:6,自引:2,他引:6  
研究台湾岛北端八斗子港和南部大鹏湾的污损生物,其湿重两个港均偏小(142和168kg/m2).共记录60个物种,两个港的共有种仅7种.八斗子港的28种中,优势种花石莼、变化短齿蛤、缘齿牡蛎、纹藤壶和冠瘤海鞘.大鹏湾29种动物中,优势种是3种管栖端足类(C.insidiosum,E.brasiliensis,E.hoobeno)、3种海鞘(P.constellotum,D.areolatum,S.canopus)、多室草苔虫和沙筛贝,后者是外来物种,还有双凸双眉藻等12种硅藻.两处的污损生物群落各自反映了亚热带和热带两类半封闭港湾污损生物的生态特点.  相似文献   
33.
南海北部沿岸污损生物中的苔藓虫   总被引:2,自引:0,他引:2  
李传燕 《台湾海峡》1992,11(1):61-68
作者于1979年9月至1989年8月,先后在广东、海南及广西沿岸港湾进行污损生物和人工鱼礁附着生物周年挂板试验,并调查沿岸港湾浮标、船只、码头、水产养殖设施及其他水下设施的污损生物,获苔藓虫3871号标本,经分析鉴定为88种,隶属3目30科。它们多数是高盐暖水种和广分布种。有少数河口低盐种,遍布于中国沿岸的有26种,黄、渤海已发表的有29种,东海31种,仅南海沿岸水域28种。南海北部沿岸苔藓虫终年都能繁殖附着,附着高峰期为冬春季节的低温月份。  相似文献   
34.
Ultrafiltration (UF) can remove natural organic matter (NOM) effectively. Moreover, chlorine dioxide (ClO2) has been an alternative disinfectant as it forms fewer disinfection by‐products with NOM than chlorination does. Therefore, combining ClO2 with UF may improve conventional purification processes. In this study, feed water containing humic acid with 4.07 mg/L total organic carbon (TOC) was dosed directly with various amounts of ClO2 (0, 2, 5, 10, and 15 mg/L) before being filtered through a 5‐kDa UF membrane. With a low dose (2 mg/L ClO2), UF removed humic acid effectively, as TOC was not detected in the permeate, and the permeate flux increased to about 80% of the initial permeate flux by cross flow. Moreover, the concentrations of ClO, ClO, and trihalomethanes in the permeate were below the United States Environmental Protection Agency guidelines.  相似文献   
35.
广东碣石湾污损生物生态研究   总被引:1,自引:0,他引:1  
2008年5月至2009年4月,对广东碣石湾海域进行周年污损生物挂板试验,本次调查共记录该海域污损生物86种,多属于亚热带沿岸的广布种,其中优势种为网纹纹藤壶(Amphibalanus reticulatus)、翡翠股贻贝(Perna viridis)、太平洋侧花海葵(Anthopleurapacifica)、水云(E...  相似文献   
36.
烟台市龙口港污损生物生态研究   总被引:1,自引:0,他引:1  
于2007年03月22日至2008年03月21日在山东省烟台市龙口港附近海域,进行了为期1年的挂板试验,本次调查共记录该海域污损生物32种,优势种为内枝多管藻(Polysiphonia morrowii)、软丝藻(Ulothrix flacca.)、肠浒苔(Entermorpha intestinalis)、中胚花筒螅(Tubularia mesembryanthemum)等.该海域全年均有污损生物附着,月板平均生物量为525.18 g/m2,5-11月的生物附着量较高,最高值出现在7月;季板平均生物量为1569.39 g/m2,生物群落的种类组成和生物量变化明显,其中秋季板生物量最高,龙口海域污损生物的附着种类受季节性水温变化的影响比较明显,藻类开始附着的温度低于动物.4个季度污损生物的种群多样性指数(H忆)春季最高,均匀度指数(J)和种群丰富度指数(M)则夏季最高.统计分析表明,龙口港海域污损生物群落可大致划分为 4个组群,秋季附着的污损生物代表了试验海域的主要特征,同时揭示出污损生物附着季节、演替时间长短等是影响群落种类组成的重要因素  相似文献   
37.
Canine faecal contamination contributes to environmental degradation and increases the exposure of humans – mainly children – to helminth infections. We studied the magnitude and spatial distribution of faecal contamination on the pavements of two neighbourhoods representative of Buenos Aires suburbs. The pavements of a low-income neighbourhood (LIN) and a middle-income neighbourhood (MIN) were selected at random. Field maps including all substrates and objects observed on each pavement were drawn, viewed from above, on millimetre paper at 1:100 scale. Data were then loaded into a geographic information system (GIS) Arc View 3.1 with a digitiser board. The spatial distribution of faeces and its association with substrates or standing elements were analysed at three scales: substrate, pavement and neighbourhood.
Permeable substrate cover was higher in LIN (75%) than in MIN (35%). The faeces were not homogeneously distributed on the substrates. In both neighbourhoods, the substrates with >50 per cent grass cover showed a significantly higher proportion of faeces than those with <50 per cent grass cover, bare soil and tile. At pavement scale, the number of faeces on pavements was not related to either the number of trees, posts and domiciled dogs in the block, or with the number of faeces and percentage cover of each substrate. At patch scale, substrate patches with faeces were larger than those without faeces. Patches with faeces did not differ in shape between neighbourhoods and were more regularly shaped than patches without faeces.
The spatial distribution of faeces relative to each other was almost random, even when analysed in relation to trees or standing objects. Strategies for the sustainable control of this problem are suggested.  相似文献   
38.
DistributionoffoulingbryozoansinthenorthernSouthChinaSeaYanYan,YanWenxia,DongYu,WangHuajie,YanTaoandLiangGuanhe(ReceivedJune2...  相似文献   
39.
膜过滤在污水处理中的应用研究进展   总被引:3,自引:0,他引:3  
膜滤是借助一定的外加压力使液体穿过膜后分离成浓缩液和渗透液的分离技术。常用于水处理的膜滤依据过滤膜孔径、被截留物质的尺寸和施加的过滤压力不同可分为微滤、超滤、纳滤和反渗透等。介绍了不同膜滤技术的渗透原理、膜的类型、过滤模型以及膜的污染与防治,概述了膜过滤在处理垃圾填埋场渗沥液和处理纺织印染工业废水以及中水回用等领域的应用,并探讨了膜滤技术今后的研究方向。  相似文献   
40.
The pleated ascidian Styela plicata (Lesueur, 1823) is a solitary species commonly found in ports and marinas around the world. It has been recorded in the Mediterranean region since the mid‐19th century. In the present work, the species’ genetic diversity was analysed, employing a 613‐bp portion of the mitochondrial cytochrome c oxidase subunit I (COI) gene from 149 individuals collected in 14 ports along Italian coasts at spatial scales ranging from 1 to approximately 2200 km. Haplotype and nucleotide diversity values were = 0–0.933 (total = 0.789) and π = 0–0.145 (total π = 0.0094), respectively. A general southward trend of increasing within‐population genetic diversity was observed. Analysis of molecular variance revealed significant genetic structuring but no significant differences were detected among basins, and no isolation by distance was found. Our data were integrated with the COI sequences available from previous studies and re‐analysed in order to investigate the possible routes of introduction of this ascidian into the Mediterranean Sea. The presence of the two COI haplogroups detected in previous molecular investigations on S. plicata at intercontinental spatial scale was confirmed in the Mediterranean Sea. The results revealed multiple introductions of S. plicata, although some locations appear to have experienced rapid expansion from few founding individuals with reduced genetic diversity. However, continuous introductions would confound the pattern deriving from single founder events and make it difficult to estimate the time needed for gene diffusion into established populations. This mixing of effects creates difficulties in understanding the past and current dynamics of this introduction, and managing this alien invasive ascidian whose genetic structure is continuously shuffled by vessel‐mediated transport.  相似文献   
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