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1.
A growing need to manage marine biodiversity sustainably at local, regional and global scales cannot be met by applying existing biological data. Abiotic surrogates of biodiversity are thus increasingly valuable in filling the gaps in our knowledge of biodiversity patterns, especially identification of hotspots, habitats needed by endangered or commercially valuable species and systems or processes important to the sustained provision of ecosystem services. This review examines the use of abiotic variables as surrogates for patterns in benthic biodiversity with particular regard to how variables are tied to processes affecting species richness and how easily those variables can be measured at scales relevant to resource management decisions.  相似文献   

2.
浙江苍南泥相潮间带春末底栖动物生态特征   总被引:1,自引:0,他引:1  
通过2003年6月对鳌江口南侧苍南县3条泥相潮间带断面的调查分析,鉴定出潮间带底栖动物74种,其中多毛类8种,软体动物24种,甲壳动物26种,棘皮动物1种,其他类动物15种。平均生物量和栖息密度分别为103.74 g/m2,667个/m2,软体动物和甲壳动物可占总生物量的72%和15%,断面数量平面分布为巴曹>白沙>海城,垂直分布中潮区>高潮区>低潮区,多样性指数H′值北侧白沙断面(1.82)大于南侧巴曹断面(1.61),均匀度J值中间海城断面为最大(0.72),调查区域北端鳌江淡水注入和南端外侧琵琶山阻挡,海流及潮汐的作用影响不一,致使该区潮间带动物种类和数量在南北断面间有较大差异。  相似文献   

3.
This study was undertaken to determine the potential for trophic transfer of polycyclic aromatic hydrocarbon (PAH) metabolites from infaunal organisms to bottom-feeding fish. Winter flounder, Pseudopleuronectes americanus, were given single oral doses of ground polychaetes (Nereis virens), either treated with pure [14C]henzo[a]pyrene (BaP) or containing a mixture of naturally produced radiolabeled BaP and BaP metabolites. Fish were sacrificed 24 h after feeding and total accumulated radioactivity and metabolite class profiles determined in major organs. Metabolites produced by worms were absorbed by flounder, although as a percentage of dose given they were less available than parent BaP. Comparison of metabolite profiles in the worm diet and in target organs in the fish indicated that metabolites accumulated through the diet can be further modified by the prey organism and can lead to the formation of bound residues. These results demonstrate that PAH metabolites in the diet are available for accumulation. Furthermore, metabolites absorbed appear to be susceptible to metabolic alteration by consumer organisms.  相似文献   

4.
Harmful benthic microalgae blooms are an emerging phenomenon causing health and economic concern, especially in tourist areas. This is the case of the Mediterranean Sea, where Ostreopsis ovata blooms occur in summer, with increasing regularity. Ostreopsis species produce palytoxin (PTX) and analogues, and a number of deaths directly associated with the ingestion of PTX contaminated seafood have been reported. PTX is considered one of the most toxic molecules occurring in nature and can provoke severe and sometimes lethal intoxications in humans. So far in temperate areas, O. ovata blooms were reported to cause intoxications of humans by inhalation and irritations by contact.In addition, invertebrate mass mortalities have been reported, possibly linked to O. ovata blooms, although other causes cannot be ruled out, such as oxygen depletion or high seawater temperature. In order to improve our knowledge about the direct toxicity of this species on invertebrate and vertebrate marine organisms, we performed an ecotoxicological screening to investigate the toxic effects of different concentrations of O. ovata (cultured in the laboratory and sampled in the field during blooms) on crustaceans and fish as model organisms. Artemia salina, Tigriopus fulvus, and Amphibalanus amphitrite larvae and juveniles of the sea bass Dicentrarchus labrax were used as model species. Toxic effects associated with cultured O. ovata cells were investigated using a crossed design: testing two different temperatures (20 and 25 °C), four different cell concentrations, and four treatments (untreated O. ovata culture, filtered and resuspended algal cells, growth medium devoid of algal cells, and sonicated algal cells). The results indicate that the toxicity of cultured O. ovata is related to the presence of living O. ovata cells, and that this effect is amplified by temperature. Furthermore, both tests with laboratory cultured algae and field sampled cells pointed out that A. salina is the most sensitive species even at concentrations below the Environmental Alarm Threshold set by the Italian Ministry of Health.Some possible explanations of such sensitivity are discussed, taking into account evidence of O. ovata cells ingestion and the activity of its toxins on the Na+/K+-ATPase.  相似文献   

5.
Sediment samples were selected from 28 sites across the deep (212–3527 m) northern Gulf of Mexico (GOM) as part of the Deep Gulf of Mexico Benthos (DGoMB) program, and analyzed for geochemical parameters related to organic carbon (OC) distribution and characteristics. The results of this study indicate that the OC content of sediments in the deep northern GOM is controlled by several factors; including water depth, overlying water productivity, sediment carbonate content, sediment oxygen exposure time, OC sources, and regional influences. The best correlation between sediment OC content, on a CaCO3-free basis, and other parameters examined was an inverse correlation of OC with water depth. The OC/SA ratio had a wide range of values and, along with variable sources of sedimentary OC, indicated that the organism-available concentration of metabolizable organic matter may not be simply related to sedimentary OC content. This was perhaps reflected in the observation that benthic macrofaunal and meiofaunal biomass abundances were well correlated with sedimentary OC, but the abundance of bacteria in sediments was not.  相似文献   

6.
厦门湾底栖生物稀土元素的含量及其分布与环境意义   总被引:4,自引:0,他引:4  
用ICP-MS法测定了厦门湾及邻近海域底栖大型藻类、软体动物、节肢动物中15种稀土元素的含量,研究了底栖生物稀土元素的组成及其分布与生态环境意义.结果表明,大型藻类稀土含量介于0.780~49.1μg/g,其中绿藻类的稀土总量最高,平均为24.3μg/g.软体动物稀土元素含量在0.365~21.6μg/g,以双壳类的稀土总量最高,平均为12.9μg/g.节肢动物稀土元素含量最低,范围是0.154~0.807μg/g.各类底栖生物的稀土配分特征总体上都表现为轻稀土元素的富集,其中铈、镧、钕在总稀土元素中所占的比例较高.多数底栖生物的北美页岩归一化稀土元素分布模式具4分组效应,但不同类别之间存在一定差异.底栖生物稀土元素含量及其分布模式表现出种类之间及地理分布上的差异,这对生态环境监测中种类的选取具有重要指导意义.  相似文献   

7.
互花米草防除药物对滩涂底栖生物影响的评价   总被引:2,自引:0,他引:2  
吕小梅  张跃平 《台湾海峡》2006,25(3):402-406
2005年7月15日对厦门海沧青礁海堤外的互花米草进行药物杀除,试验选用的除草剂对互花米草的杀除有效.药物喷洒后不同时段调查结果表明:试验区与对照区的底栖生物种类组成、生物量、栖息密度同步对比数量相差不明显,其随时间变化的趋势亦呈现总体一致.这表明互花米草防除药物对底栖生物群落组成结构及其生境的干扰不大,试验区与对照区底栖生物群落组成结构总体一致的变化趋势与时序有关.  相似文献   

8.
Concentrations of twelve metals were determined in sediments, seaweed (Fucus vesiculosus), winkles (Littorina littorea), polychaetes (Nereis diversicolor), suspension feeding bivalves (Mytilus edulis, Cerastoderma edule) and deposit feeding bivalves (Macoma balthica, Scrobicularia plana) collected from the Mersey estuary between April 1980 and June 1984.Sediments and organisms in the Mersey are moderately contaminated with most of the metals measured, but mercury concentrations are consistently higher than in other United Kingdom estuaries. Comparisons with other sites in the North West of England indicate that mercury residues in organisms, though primarily dependent on sediment concentrations, are also influenced by complexation with particulate organic matter which reduces the availability of mercury. The biological availability of arsenic in Mersey sediments is similarly influenced by complexation with iron oxyhydroxides.Nereis diversicolor and Macoma balthica are the most suitable indicator species in terms of abundance and widespread distribution along the estuary, and, for the majority of metals, tissue concentrations increase upstream, reflecting corresponding gradients in sediment contamination. However mid-estuarine peaks for tin, chromium copper and nickel in Nereis indicate more localised inputs to the estuary. Correlations between lead in sediments and organisms are poor; it is suggested that hydrophilic alkyl lead compounds may be the predominant biologically available forms.Progressive reductions in mercury contamination in sediments and mercury and lead in organisms have occurred in recent years, which coincide with efforts to reduce inputs of these metals to teh Mersey estuary.  相似文献   

9.
10.
This paper presents the results obtained during a four-year study of heavy metal distribution in certain organisms of the Ligurian Sea. The species which we have considered (mussels, mullet, shrimp and anchovies) were systematically sampled from December 1976 to December 1980, and were taken from the area between Punta del Mesco (east of Genoa) and Savona (west of Genoa).The metals (Hg, Cd, Cu, Mn, Pb and Zn) were determined using atomic absorption spectrometry of the solutions obtained by mineralizing the samples with HNO3 at 90% in decomposition flasks fitted with a reflux condenser.The values obtained depend upon the place and year of sampling and are compared to values found by other authors for the same organisms in the other Italian seas.  相似文献   

11.
海洋生物中硒的催化动力学光度测定与形态分布研究   总被引:6,自引:0,他引:6  
许卉  贺萍 《海洋科学》2004,28(2):36-39
建立了一种测定海洋生物中不同形态硒的催化动力学光度法。在pH=3的Clark—Lubs缓冲介质中,硒(Ⅳ)能催化溴酸钾氧化甲基紫的褪色反应,硒(Ⅳ)含量在0.14~8μg/L范围内与褪色反应速率成正比,生物样品经HNO3-HClO4消化后直接测定硒(Ⅳ)和有机硒含量,再经盐酸还原后测定总硒含量,两者差减得硒(Ⅵ)含量。结合MIBK(甲基异丁基酮)萃取分离干扰组分,该方法具有良好的选择性和准确度,用于海洋生物材料中不同形态硒的测定,操作简便快速,结果令人满意。对几种海藻和双壳贝类样品中硒的形态分析结果表明,在海洋生物中,硒主要以有机硒和硒(Ⅳ)的形式存在于难溶性的大分子蛋白质中,硒(Ⅵ)的含量普遍较低,且存在显著的种间差异。  相似文献   

12.
A series of experiments were conducted to develop standard test organisms and test protocols for measuring sediment toxicity using candidate amphipods such asMandibulophoxus mai, Monocorophium acherusicum, Haustorioides indivisus, andHaustorioides koreanus, which are indigenous to Korea. The relevant association of test species with sediment substrates was one of the important factors in sediment bioassay. The indigenous amphipodsM. mai andM. acherusicum were well associated with test sediments when they were exposed to various sediment substrates from sand to mud. The tolerant limits to various physico-chemical factors affecting bioassay results such as temperature, salinity and ammonia, as well as sensitivities to reference toxicant and contaminated sediments, were investigated usingM. mai andM. acherusicum in the present study. These amphipods were tolerant to relatively wide ranges of salinity (10~30 psu) and ammonia (<50 ppm), and displayed relevant sensitivity to temperature as well. They are more sensitive to Cd, the reference toxicant, when compared to the standard test species used in other countries. Field-sediment toxicity tests revealed thatM. mai would be more sensitive to sediment-associated pollutants thanM. acherusicum, while the sensitivity ofM. acherusicum was comparable to that ofLeptocheirus plumulosus, which has been used as a standard test species in the United States of America. Overall results of this first attempt to develop an amphipod sediment toxicity test protocol in Korea indicated thatM. mai andM. acherusicum would be applicable in the toxicity assessment of contaminated sediments, following the further evaluation encompassing various ecological and toxicological studies in addition to test method standardization.  相似文献   

13.
Marine benthic surveys and monitoring programs may have several goals. When the aim of such studies is to reveal and describe gradients in species composition, the gain in ecological insight achieved by the study depends on how well the spatial variability of species’ occurrence and abundance within the study area is covered by the sampling design. The common practice in such programs is to collect four or five grab samples from each visited site to capture the site's species composition. The rationale for this practice is based on the aim of capturing a large proportion of species at a specific site (i.e. point). We argue that this practice has been established without taking Iterative approaches into account, such as decreasing the sampling effort at each site and instead increase the number of sites visited. The collection and processing of data from marine sediment ecosystems are time‐consuming and, thus, expensive. Therefore, finding the optimal trade‐off between the number of sites visited and the number of samples per site is important. We examined this trade‐off by exploring how reduction of sampling effort per site affects the stability and recovery of gradients in species composition of marine benthic macrofauna. Our full data set consisted of four grab samples from each of 28 sites from the inner part of the Oslofjord, SE Norway. Procrustes analysis and calculation of Kendall's rank correlation coefficients showed that the main gradient in species composition extracted by detrended correspondence analysis of data sets with reduced per‐site sampling effort closely resembled the main gradient extracted for the full data set. Our results therefore suggest that marine benthic surveys that aim to identify the main gradient structure of species composition and relate this structure to main environmental complex gradients are likely to benefit from reducing the sampling effort at each site and, instead, increasing the number of visited sites. We argue that coverage of both the variation in species composition and the environment in the study area will then be improved. Monitoring programs with other aims than to identify the main gradients in species composition may also benefit from the adoption of a many‐sites, one‐sample sampling strategy. This may be particularly true if additional sampled sites are based on a stratified sampling strategy that ensures that the spatial variability in the study area is accounted for.  相似文献   

14.
Avoiding the subject for fish accumulation, the traditional view in fish population dynamics has ascribed immigration and emigration of fish to dispersal of fish. The main purpose of this paper is to find a quantity that represents the time rate of accumulation-dispersal of marine organisms, and also has some relation to the horizontal convergence of current velocity of the surrounding water. For this, the accumulation-dispersal coefficient is introduced not in the form of diffusion, but in the same form as the convergence. Since the accumulation-dispersal of organisms is a factor that changes its distribution density, all factors causing the change are first classified to locate the position occupied by the accumulation dispersal. Each factor corresponds to each coefficient appearing in a linearized equation describing the rate of change in the density, averaged over a region or a group. The immigration-emigration coefficient is divided into three coefficients of passage, accumulation dispersal and diffusion velocity. For the organisms ranging in a nearly horizontal layer, the accumulation-dispersal coefficient is shown to equal the area-averaged horizontal convergence of organismal velocity relative to land, which is the sum of the area-averaged horizontal convergences of swimming velocity relative to water and of current velocity. However, the area-averaged convergence of current velocity associated with the accumulation-dispersal coefficient for a region is shown to be somewhat different from the usual one.  相似文献   

15.
海洋底栖原生动物生态学研究方法学综述   总被引:3,自引:1,他引:3  
在浮游生态系统(pelagic ecosystem)中,原生动物是细菌和微型浮游植物(microphytoplankton)的主要捕食者,又是很多浮游动物(zooplankton)的重  相似文献   

16.
Field concentrations of polychlorinated biphenyls (PCBs) were measured in sediment and nine marine soft bottom invertebrate species. Lipid- and organic carbon normalised biota-sediment accumulation factors (BSAFs) were determined for 29 nonplanar and 11 coplanar congeners. To investigate whether the bioaccumulation was in thermodynamic equilibrium with the sediment, the determined BSAFs were compared to theoretically calculated ones to obtain a BSAFdet./BSAFtheor-ratio. Large interspecific variations were found: one suspension feeding and one deposit feeding species of brittle stars (Amphiura filiformis and A. chiajei), and one predatory polychaete (Glycera rouxii) had ratios>1 for congeners with logKow>6.5. In these species there was also a linear relationship between logKow and BSAF, both for coplanar and for planar congeners but with lower values for coplanar ones. For other species the pattern was more scattered. Only the deposit feeding polychaete Melinna cristata had BSAFdet./BSAFtheor-ratios<1 for all congeners. Thus, the interspecific variations in bioaccumulation did not correlate with differences in feeding strategies, but may be caused by differences in biotransformation, and in age and size of the analysed specimens.  相似文献   

17.
The incorporation of the ecosystem approach into marine planning requires that all aspects of value associated with marine biodiversity are incorporated into the decision making process. An ecosystem services approach to valuing marine biodiversity is recognised as a framework by which economic, ecological and social values may be incorporated into the decision making process. There are sectors of the marine leisure and recreation industry (sub-aqua diving, sea angling and wildlife watching), which depend on the presence of natural marine resources in order to carry out their activity. Estimating the value of this direct use can provide an evidence base for the sustainable use of marine biodiversity when set against other competing economic interests in marine spatial planning. In the case study area of Lyme Bay, the marine leisure and recreation industry has been valued using both monetary and non-monetary methods. The results show that the leisure and recreation industry is dependent on the diversity of sites (many of which are currently unmanaged) and that the industry is of economic significance and an area which has recently been closed to trawling activity enables the protection of some of the most valuable sites but has limited benefits for protecting the full resource base upon which this local industry depends.  相似文献   

18.
白树猛  田黎 《海洋科学》2010,34(1):80-83
伴随着社会经济和工业的快速发展,人口的不断增长,在生产和生活过程中产生的废弃物也越来越多,这些废弃物的绝大部分最终直接或间接地进入海洋.当这些废物和污水的排放量达到一定的限度,海洋便受到了污染.污染海洋的物质众多,按污染物的性质和毒性,以及对海洋环境危害方式,大体可以把污染物分成以下几类:一是营养盐类和有机物质,如工业排出的无机氮、磷酸盐等,生活污水中的粪便、洗涤剂等;二是重金属和酸碱类物质如汞、铜、锌、镉等重金属,以及砷、硫、磷等非金属和各种酸碱;三是有毒化学制品,主要是化肥和农药的残留物[1,2].  相似文献   

19.
Recurrent climate‐induced mass mortality episodes have been recorded in the Mediterranean Sea over the past 15 years, affecting rocky benthic communities. In this study, we provide for the first time a report on the annual mortality events of benthic sessile invertebrates occurring in the eastern part of the Adriatic Sea. Over the course of 14 consecutive years, we studied the sea temperature gradient to a depth of 40 m and found an abnormal summer warming trend and an increased frequency of above‐average temperatures. Mortality events were recorded in the summers of 10 observed years, in particular in 2009, when the highest mortality rates were recorded. Late in summer 2009, extensive mass mortality of sessile invertebrates was observed in the entire Eastern Adriatic Sea. We performed an analysis of selected target benthic species associated with mass mortality events with inter‐regional differences in hydrological and temperature conditions. We were able to characterize the mortality event by studying five areas covering the northern, central and southern regions of the Eastern Adriatic Sea. The degree of impact on each study area was quantified at 28 sites by estimating the proportion of affected target species. According to the obtained data, the northern sites (Cres area) were the least affected, whereas sites in the Central and Southern Adriatic [Tela??ica and Lastovo Nature Parks, Mljet National Park (NP)] displayed the highest impact. In summer 2009, sea surface temperatures reached values of 28 °C in the Cres area and 30 °C in Mljet NP. These thermal conditions were concomitant with moderate to severe mass mortalities of benthic populations. Mass mortality events reached depths of 45 m in most parts of the affected areas. Amongst studied species, the scleractinian coral and gorgonian populations suffered the most extensive damage during the mass mortality events.  相似文献   

20.
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