泉州湾蟳埔潮间带大型底栖动物群落的时空分布

为了比较泉州湾蟳埔潮间带沙滩、互花米草滩和牡蛎石泥滩3种生境(3个潮层)的大型底栖动物群落,2011年4月至2012年1月对3种生境的大型底栖动物进行了季度定量取样。在3种生境共获得85种大型底栖动物,其中环节动物39种,软体动物20种,节肢动物21种,刺胞动物、扁形动物、纽虫动物、星虫动物和脊索动物各1种。多维标度排序(MDS)分析表明,春季和冬季泉州湾蟳埔潮间带3种生境的大型底栖动物群落相似性较低;夏季和秋季互花米草滩与牡蛎石泥滩的大型底栖动物群落相似性较高,而与沙滩的大型底栖动物群落相似性较低。沙滩大型底栖动物群落的季节变化较明显,其次是牡蛎石泥滩,而互花米草滩大型底栖动物群落的季节变化较不明显。大型底栖动物栖息密度和生物量随着潮层降低而增加。单变量双因素方差分析(Two-way ANOVA)表明,不同生境之间的大型底栖动物物种数、栖息密度、多样性指数、均匀度指数和丰度指数有显著差异,但生物量无显著差异,这是因为沙滩的物种数较少,栖息密度较低,但优势种弧边招潮蟹(Uca arcuata)个体较大,互花米草滩和牡蛎石泥滩的优势种为加州中蚓虫(Mediomastus californiensis),个体相对弧边招潮蟹小。不同季节之间大型底栖动物物种数、栖息密度、生物量和丰度指数有显著差异,但多样性指数和均匀度指数元显著差异,这是因为沙滩物种数少,但个体分布比较均匀,而互花米草滩和牡蛎石泥滩物种数较多,个体分布较不均匀。以上结果表明,潮汐、沉积物粒径和生境是影响潮间带大型底栖动物群落的主要因素。潮汐导致潮间带的空间异质性,空间异质性导致大型底栖动物群落的差异。     

柘林湾-南澳岛潮间带冬夏两季大型底栖动物种类组成及优势种

依据柘林湾-南澳岛潮间带2011年8月、2012年2月、2013年2月和8月的大型底栖动物调查资料,对该海域潮间带的大型底栖动物种类组成和优势种进行研究。结果表明:4次调查共采集到大型底栖动物7门112种,主要由软体动物、节肢动物和环节动物3大类组成;总种类数夏季冬季;夏季2次调查的类群种类数组成存在显著性差异(P0.05),冬季2次调查不存在显著性差异(P0.05),冬夏两季不存在显著性差异(P0.05);冬季→夏季的种类更替率较高,该段时间内群落的变动相对较大,稳定性相对较低;4次调查出现优势种共有23种,优势种组成最多的为软体动物;柘林湾-南澳岛附近海域潮间带生物的种类和分布由底质类型决定,同时,人类活动对海域的生物生态也造成了一定的压力。     

胶州湾大型底栖动物的物种多样性现状

自1998年2月－1999年11月对胶州湾的10个站进行了大型底栖动物分布状况调查,目的在于为进一步的胶州湾生物多样性变化及其保护研究,为胶州湾底栖生物资源的合理开发和持续利用提供科学依据和积累资料。初步分析结果显示,两年内各站春季和秋季的物种多样性指数偏低,冬季和夏季的指数较高,物种均匀度指数夏季最高,春季最低,物种丰富度指数以夏季最高,春季和冬季略同,秋季最低。1999年各站出现的底栖动物种数明显高于1998年,差异显著,生物多样性平均指数较1998年有所下降。     

Temporal and spatial variability of mobile fauna on a submarine cliff and boulder scree complex: a community in flux

The mobile component of a community inhabiting a submarine boulder scree/cliff was investigated at Lough Hyne, Ireland at dawn, midday, dusk and night over a 1-week period. Line transects (50 m) were placed in the infralittoral (6 m) and circumlittoral (18 m) zones and also the interface between these two zones (12 m). The dominant mobile fauna of this cliff consisted of echinoderms (6 species), crustaceans (10 species) and fish (23 species). A different component community was identified at each time/depth interval using Multi-Dimensional Scaling (MDS) even though both species diversity (Shannon–Wiener indices) and richness (number of species) remained constant. These changes in community composition provided indirect evidence for migration by these mobile organisms. However, little evidence was found for migration between different zones with the exception of the several wrasse species. These species were observed to spend the daytime foraging in the deeper zone, but returned to the upper zone at night presumably for protection from predators. For the majority of species, migration was considered to occur to cryptic habitats such as holes and crevices. The number of organisms declined during the night, although crustacean numbers peaked, while fish and echinoderms were most abundant during day, possibly due to predator-prey interactions. This submarine community is in a state of flux, whereby, community characteristics, including trophic and energetic relationships, varied over small temporal (daily) and spatial (m) scales.     

Spatial variations in macrobenthic fauna recolonisation in a tropical mangrove bay

Recolonisation by crab species and sediment-infauna taxa (at class level) in artificially regenerated mangrove stands of Avicennia marina, Rhizophora mucronata and Sonneratia alba (5 yr old) were studied using respective bare sites (open without mangroves or denuded) and natural sites (relatively undisturbed) as controls. The controls were chosen based on site history, physical proximity and tidal inundation class in reference to the particular reforested mangrove stand and samples randomly taken. A number of environmental variables were measured; interstitial water salinity and temperature (measured at low tide) were lower, whereas sediment organic matter content was higher in the areas with mangrove cover, with the natural sites having the highest content. The bare sites were generally sandier, whereas the areas with mangrove cover had higher proportions of clay and silt. Generally, there was a higher crab density in the reforested sites than in the bare sites, whereas crab species diversity (Shannon diversity index) did not vary from one site to another for any of the mangrove species. In terms of crab species composition, the reforested sites were more similar (Sørensen similarity coefficient) to the natural sites and less to the bare controls. For sediment-infauna, the reforested sites had a significantly higher density than the respective bare controls, while the natural sites had the highest density. The number of sediment-infauna taxa in both the reforested and natural sites of all the mangrove species was similar and higher than in the comparable bare sites. The results suggest that the reforested sites are supporting more faunal recolonisation, and therefore becoming more akin to the natural mangrove sites in terms of the investigated functional indicators. The findings seem to support the use of artificial mangrove regeneration (in areas where natural regeneration has been impeded by physical conditions or otherwise) as an effective management tool in the restoration and conservation of the functional integrity of degraded mangrove habitats.Key words: Crabs, Environmental variables, Kenya, Recolonisation, Restored mangroves, Sediment-infauna     

胶州湾大型底栖动物生物多样性现状

根据自1998年2月至2001年11月对胶州湾的10个站15个航次（每季度月一次）的大型底栖动物分布状况调查资料,报道了胶州湾大型底栖生物物种多样性现状,采用了香农-威纳指数、物种丰富度指数以及物种均匀度指数对胶州湾大型底栖生物的群落结构、种类组成、优势种以及数量动态趋势进行了分析。本次调查共采到底栖动物322种,其中多毛类44科133种,甲壳动物42科92种,棘皮动物仅有14种。各站获得平均种类数在8—26种之间,种类最少的出现在7号站,最多的出现在3号站。各站位香农-威纳指数也有很大差异,最大的是2001年11月的8号站,最小的则出现在2001年8月的9号站。7号站和9号站种类数、物种多样性指数及物种丰度指数均较低,这是因为它们位于水流较大的区域,且底质为粗砂。3号站虽然种类数较多,并具有较大的香农-威纳指数,但它的物种均匀度指数却非常低,这是因为3号站靠近菲律宾蛤仔养殖区域,蛤仔的高密度降低了均匀度指数。生物多样性除了受种的数量及其个体密度的影响外,还与多种环境因素有关,如水温,盐度、初级生产力等,人为因素（如污染、过度利用）对底栖生物影响非常大。目的在于为进一步研究胶州湾生物多样性变化及底栖生物资源的合理开发和持续利用提供科学依据和积累资料。     

Denitrification: ecological niches,competition and survival

Organisms with the denitrification capacity are widely distributed and in high density in nature. It is not well understood why they are so successful. A survey of denitrifying enzyme content of various habitats is presented which indicates a role of carbon and oxygen, but not nitrate, in affecting denitrifier populations. It is suggested that organic carbon is more important than oxygen status in determining denitrifying enzyme content of habitats. In low oxygen environments, denitrifiers compete with organisms that dissimilate nitrate to ammonium, a process which conserves nitrogen. The energetic and kinetic parameters that affect this competition are evaluated. The latter is examined using Michaelis-Menten theoretical models by varying V_max, K_m, and S_o (substrate concentration) for the two competing populations. The outcome predicted by these models is presented and discussed in relation to previous data on population densities and K_m values for representatives of these competing groups. These models suggest the conditions required to achieve changes in partitioning between the two fates of nitrate. These considerations are important if one is to be able to evaluate and successfully “manage” the fate of nitrate in any habitat.     

胶州湾大型底栖软体动物物种多样性研究

1998年2月至2004年11月,共7年27个航次对胶州湾10个站进行综合调查,研究了其大型底栖软体动物的多样性现状(菲律宾蛤仔(Ruditapesphilippinarum)除外)并探讨其成因。结果表明:在胶州湾共发现62种底栖软体动物,优势种是滑理蛤(Theoralubrica)和豆形胡桃蛤(Nuculafaba)。从1998年至2004年期间物种多样性指数(H′)年际间波动幅度不大,且无明显的规律性变化;但季节变化明显,秋季和冬季较高,春季和夏季较低。物种均匀度指数(J)则为秋季最高(0.87),夏季最低(0.58)。物种丰富度指数(D)除夏季相对较低(1.82)外,其他三个季节差别不大。     

Weak phylogenetic effects on ecological niches of Sylvia warblers

To understand the evolution of ecological niches it is important to know whether niche evolution is constrained by phylogeny. We approached this question for Sylvia warblers by testing if closely related species are more similar in 20 ecologically relevant morphological traits than distantly related species. Phylogenetic relatedness was quantified using a molecular phylogeny based on the mitochondrial cytochrome b gene. By Principal Component Analysis (PCA) two major niche axes were extracted. We tested the individual ecomorphological traits and the positions of the species on the PCA axes for phylogenetic effects using Mantel tests. The results demonstrated small but significant phylogenetic effects only for the length of the middle toe, a trait probably correlated with locomotion. In general, however, phylogenetic effects were very weak. This suggests that ecological niches in passerine birds have the potential to evolve rapidly and are not subject to major phylogenetic constraints.     

Coexistence of carnivores in a heterogeneous landscape: habitat selection and ecological niches

Understanding distributional patterns and mechanisms used by species for habitat selection is crucial to adopt effective land management policies in terms of biodiversity conservation. A heterogeneous landscape may allow coexistence of species. That coexistence will be dependent on the availability of the resources in the habitat that has to be sufficient to fulfil their basic needs. The present study aimed to investigate habitat selection, niche breadth and niche overlap of three sympatric carnivore species (Vulpes vulpes, Genetta genetta and Martes foina) in a typically fragmented landscape from Central Portugal, using camera-trapping techniques. The results obtained revealed that the investigated species use the available habitats differently and in a non-random way. The red fox showed the most specialized behaviour, positively selecting coniferous forests. The common genet preferred eucalyptus, avoiding old-growth mixed woodland, in contrast with stone marten that exhibited a strong preference for this late habitat, avoiding eucalyptus. Concerning the niche breadth, the genet had the highest value while the red fox had the lowest one. The results obtained at the camera-trap level showed that the highest niche overlap occurred between the genet and the stone marten which suggests that these species can coexist and share the available resources. Regarding the habitat level, the greatest niche overlap was found for the stone marten and the red fox, indicating the exploration of the same general habitat conditions by both species. The results obtained in the present study support the concept that landscape complexity allows coexistence between species within the same trophic level.     

Response of intertidal macrobenthic communities and primary producers to mitigation measures in a temperate estuary

The main goal of this study was to evaluate the response of intertidal macrobenthic communities associated with Zostera noltii meadows in a temperate estuary (Mondego, Portugal) to the application of mitigation measures aimed at decreasing eutrophication symptoms. In order to assess possible ecological improvements regarding the seagrass habitat and associated macrobenthic communities, data from four different periods, corresponding to the prevailing conditions of distinct systems, were considered. This study (1) gives concrete examples of pathways of benthic intertidal communities’ degradation and recovery; (2) it analyses a long-term dataset (covering almost 25 years) of intertidal communities from a southern European estuary; (3) it is focused on a worldwide problem, and so has potentially far-reaching interest; (4) it exemplifies some of what may be the consequences of the dialogue between science and managers; (5) it assesses the impact and effectiveness of a large-scale mitigation intervention paid for by public funding.The application of preliminary mitigation measures (in 1998) and the full re-establishment of the communication between the two estuarine subsystems (in 2006) allowed for an improvement in the macrobenthic condition and confirmed that hydrologic conditions in the estuary have been the major drivers of the changes observed over the last two decades. However, evaluating the efficiency of the large-scale intervention proved to be a complex task since different communities showed distinct pathways and momentums of recovery.The present study provided valuable insights concerning sustainable long-term management solutions regarding the Mondego Estuary. These particular insights could therefore be useful as a management action guideline applied to other estuarine ecosystems undergoing similar eutrophication problems.     

Semi-quantitative study of macrobenthic fauna in the region of the South Shetland Islands and the Antarctic Peninsula

During the BENTART 95 Expedition, 24 Agassiz trawls for macrozoobenthos sampling were carried out at depths of 40–850 m, from north of Livingston Island to the Antarctic Peninsula. The samples were analysed using a semi-quantitative method, and with the resulting numerical data, transformed into a six-point scale, we constructed a Bray-Curtis similarity matrix. A total of 74,624 specimens, belonging to 38 taxonomic groups, were collected. The most abundant group was Polychaeta Sedentaria, with 36% of the total, whereas the highest relative masses were from Ascidiacea (23%), Echinoidea Regularia (18%) and Ophiuroidea (16%). The maximum number of specimens recorded was 15,600 ind./50 l. Cluster analysis separated stations located in Foster Bay (Deception Island), characterised by low taxonomic richness and high relative mass (average: 26.7 kg). A zonation of ascidians, regular sea urchins and ophiuroids was observed at Deception Island, clearly related to depth and substratum type. The remaining stations were separated into two groups. The first one comprised the shallowest stations (40–130 m), dominated by sessile active filter-feeders, belonging to Ascidiacea, Demospongia and Bryozoa, and probably related to high primary production zones. The second group comprised deeper stations and was dominated by classes exhibiting a diversity of trophic strategies: Ophiuroidea and Asteroidea, to 400 m, and Polychaeta Sedentaria at greater depths. Received: 20 February 1997 / Accepted: 8 September 1997     

Invasive aphids of the tribe Siphini: a model of potentially suitable ecological niches

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Temporal and spatial variability in stable isotope compositions of a freshwater mussel: implications for biomonitoring and ecological studies

Stable isotopes can be used to elucidate ecological relationships in community and trophic studies. Findings are calibrated against baselines, e.g. from a producer or primary consumer, assumed to act as a reference to the isotopic context created by spatio-temporal attributes such as geography, climate, nutrient, and energy sources. The ability of an organism to accurately represent a community base depends on how, and over what time-scale, it assimilates ambient materials. Freshwater mussels have served as references for trophic studies of freshwater communities and as indicators of change in nutrient pollution load or source. Their suitability as reference animals has not yet been fully explored, however. We conducted a series of studies examining the suitability of freshwater mussels as isotopic baselines, using their ability to reflect variation in ambient nutrient loads as a case scenario. (1) We analyzed bivalve foot tissue δ¹⁵N and δ¹³C from 22 stream reaches in the Piedmont region of North Carolina, USA to show that compositions varied substantially among locations. Site mean bivalve δ¹³C values correlated with site ambient particulate organic matter (POM) δ¹³C values, and site mean bivalve δ¹⁵N values correlated with site ambient water dissolved δ¹⁵N-NO₃ values. (2) Similarity of results among sample types demonstrated that the minimally invasive hemolymph sample is a suitable substitute for foot tissue in δ¹⁵N analyses, and that small sample sizes generate means representative of a larger population. Both findings can help minimize the impact of sampling on imperiled freshwater mussel populations. (3) In a bivalve transplantation study we showed that hemolymph δ¹⁵N compositions responded to a shift in ambient dissolved δ¹⁵N-NO₃, although slowly. The tissue turnover time for bivalve hemolymph was 113 days. We conclude that bivalves serve best as biomonitors of chronic, rather than acute, fluctuations in stream nutrient loads, and provide initial evidence of their suitability as time-integrated isotopic baselines for community studies.     

珊瑚藻类对南麂列岛潮间带底栖生物群落多样性的影响

为了解南麂列岛潮间带珊瑚藻类对于其他大型藻类和底栖动物的影响, 在南麂列岛国家级海洋自然保护区布设了4条潮间带断面, 于2012年5月至2013年2月对其生物状况进行了逐季调查, 分别分析了中低潮区大型藻类、非珊瑚藻大型藻类、底栖动物的物种多样性和均匀度, 并计算了大型底栖动物的功能多样性指数Rao's Q。主要结果如下: (1)共采集和鉴定出大型藻类52种, 其中珊瑚藻科藻类有5种; (2)珊瑚藻类在高潮区没有分布, 在中低潮区均占据优势, 占潮间带藻类生物量的68.9%。四季中低潮区大型藻类的Shannon-Wiener多样性指数范围为1.638-4.044, 非珊瑚藻大型藻类的多样性指数范围为1.495-3.809, 底栖动物为5.289-6.917; 大型藻类的Pielou均匀度指数范围为0.819-0.971, 非珊瑚藻大型藻类的均匀度指数范围为0.830-0.973, 底栖动物为0.967-0.988; (3)大型藻类物种多样性和均匀度指数的降低与珊瑚藻类优势度的增加相关, 但珊瑚藻类优势度与底栖动物物种多样性指数、均匀度指数和功能多样性指数均没有显著相关性; (4)底栖动物功能多样性与珊瑚藻类优势度均呈低潮区高于中潮区的变化规律, 但相关性分析表明两者间并无直接联系。推测珊瑚藻类通过竞争占据了其他藻类的生存空间, 从而降低了南麂列岛潮间带大型藻类的物种多样性和均匀度。底栖动物则因其自身生活特点而使得珊瑚藻类的扩张未能影响其多样性水平。     

福建同安湾潮间带红树林生境与非红树林生境大型底栖动物群落比较

底栖动物群落是红树林生态系统多样性研究的重要内容之一。为了解大型底栖动物群落对高有机质含量和富营养的红树林生境的响应, 从2006年4月到2007年1月, 对福建省同安湾红树林生境和非红树林生境大型底栖动物群落及其时空变化进行了研究。我们在同安湾红树林种植区设置了凤林(FL)和山后亭(XA)两条断面, 每条断面在红树林内各设2个取样站(FL1, FL2, XA-A和XA-B), 林外各设1个取样站(FL3和XA-C)。底质研究结果显示凤林3个取样站(FL1, FL2和FL3)的有机质含量均超过底质污染评价标准的临界值3.4%, 且无论凤林还是山后亭, 红树林生境的有机质含量均要高过非红树林生境。共获得大型底栖动物91种, 其中在红树林生境内获得77种, 高于非红树林生境内获得的67种。红树林生境和非红树林生境的大型底栖动物平均栖息密度分别为4,445.8 inds/m2 和1,707.2 inds/m2, 平均生物量分别为51.1 g/m2 和 94.6 g/m2。独立样本t-检验结果显示, 红树林生境和非红树林生境大型底栖动物平均栖息密度和平均生物量均存在显著差异。研究结果指示红树林生境对于寡毛类生存(如在高耐有机污染中能大量繁殖的沼蚓)有积极作用。但由于邻近的非红树林林生境的水淹时间更长, 一些具有移动能力的软体动物和甲壳动物能迁移到更适合生存的非红树林生境中去。其他底质因子如盐度和土壤中值粒径等也会影响大型底栖动物群落变化。     

Microhabitat variability of macrobenthic organisms within tidal creek systems

The historical development of the hydroseral vegetation of three humic lakes was studied. We applied a combination of methods to reconstruct the past vegetation (plant macroscopic remains, peat decomposition, sediment chemistry and radiocarbon dating). The contemporary environment of these lakes was assessed by vegetation and water chemistry analyses. The oldest foreshore sediments were formed 13075–12700 cal BP (Lake Suchar VI), 10115–9670 cal BP (Lake Suchar III) and 8747–8479 cal BP (Lake Widne). The differences in contemporary vegetation are reflected in the subfossil plant assemblages. From the beginning, poor fens and bogs occurred beside Lake Suchar III, moderately rich and poor fens were developed at Lake Suchar VI, while reedswamps and moderately rich fens occurred at Lake Widne. The foreshore vegetation changed over time but only within a restricted range, specific for each lake corresponding to the hydrochemical differences between the lakes. Lakes are classified as humic if some features are combined, such as the specific vegetation and water parameters. However, over the past few decades escalating climatic and anthropogenic changes could transform the character of these water bodies. The application of multidisciplinary methods permitted comparison of the development of three apparently similar lakes and identification of significant ecological differences.     

几种十字花科蔬菜害虫生态位的研究

以Levins生态位宽度指数和Pianka生态位重叠指数估计发生在同一营养阶层的 4种主要十字花科植物害虫营养生态位、时间生态位和空间生态位的生态位宽度和重叠度。结果表明小菜蛾、黄曲条跳甲、菜粉蝶和小猿叶甲 4种昆虫的生态位并不完全重叠。