Bottom Communities of Nyivo Lagoon (Northeastern Sakhalin)

Clasterization of benthic stations by biomass of common species using an index of coenotic similarities allowed us to distinguish three communities of macrophytobenthos (Zostera marina + Z. japonica, Zostera japonica, and Potamogeton pectinatus) and eight macrozoobenthos communities (Macoma balthica, Limnodrilus hoffmeisteri + Anisogammarus tiuschovi, Spio filicornis + Archaeomysis grebnitzkii, Kamaka kuthae, Glyptotendipes paripes, Neomysis awatschensis + Dolielinotus moskvitini, Neomysis mirabilis, and Anisogammarus tiuschovi + Littorina sitkana + Crangon septemspinosa). The bulk of the bottom surface is occupied by a community of Zostera marina + Macoma balthica with the mean biomass of the dominating species reaching 0.3–1386.6 and 573.9 g/m², respectively. Specific geomorphologic and hydrologic features, as well as the presence of many estuarine areas in Nyivo Lagoon, provide conditions for numerous different fresh-and brackish water communities and variations of them. However, bottom communities cannot be clearly separated into mostly freshwater and mostly brackish communities, which is the case for Pil'tun Lagoon, a well studied lagoon in eastern Sakhalin. Several decades of timber rafting in the Tym' River has had a significant effect on bottom biota and the communities of Nyivo Lagoon. Considering the well-known negative effects of phenol and its derivatives on benthic biota and communities derived during timber decomposition, the sources of pollution of the natural environment in the lagoons of eastern Sakhalin must be evaluated and differentiated.     

Fouling Communities of Hydrotechnical Constructions in Nakhodka Bay (Sea of Japan)

The fouling of mooring facilities in Nakhodka Bay, Sea of Japan, has been studied. The main fouling communities have been distinguished dominated by green algae Enteromorpha linza and Ulva fenestrata, brown algae Laminaria japonica and Costaria costata, a hydroid Obelia longissima, a polychaete Pseudopotamilla occelata, cirripede barnacles Balanus crenatus and Semibalanus cariosus, a bivalve mollusk Mytilus trossulus, and an ascidian Halocynthia aurantium. The naturalization of some species-invaders in the fouling of mooring facilities in Nakhodka Bay has been registered, namely hydroids Laomedea flexuosa and Clytia languida, a polychaete Pseudopotamilla occelata, and a bryozoan Bowerbankia gracilis.     

Species Structure of Plankton Microalgae on the Coast of the Sea of Okhotsk on Sakhalin Island

The results of long-term studies of the species structure of microalgae plankton of the coast of the Sea of Okhotsk of Sakhalin Island were summarized. There were 227 species and 4 intraspecific taxa attributed to 8 divisions. The greatest number of species was represented by the divisions Bacillariophyta (112 species and 3 intraspecific taxa) and Dinophyta (96 and 1 respectively). For the first time 5 diatom, 4 dinoflagellate, and 1 euglenophyte species were recorded for the Sea of Okhotsk.     

Macrobenthos of Brackish-Water Areas in the Intertidal Zone of Del''fin Bay (Shikotan Island, Small Kuril Islands)

The paper describes brackish-water areas of Del'fin Bay and provides quantitative characteristics of macrobenthos communities in these areas considering changes that took place after the lowering of the island and a result of the earthquake of 1994. A comparative biogeographical analysis have been performed of brackish-water areas in Del'fin Bay in comparison with open seaward Gorobets Bay (Shikotan Island). The most peculiar elements of biota in the brackish-water areas are represented by marine eurybionthic and brackish-water species of the subtropical–low boreal complex. The communities of brackish-water areas of Del'fin Bay have been referred to the Amur-Japanese Subprovince of the Sino-Indian Brackish-Water Province, unlike the assemblage of organisms in typically marine coasts of Shikotan Island, which are referred to the Low-Boreal Subprovince (Subzone) of the marine Pacific Boreal Province (Zone).     

Trophic Assemblages of the Rocky Intertidal Zone in Vostok Bay,Sea of Japan

The ratios between the indices of relative abundance for different trophic life forms have been used to characterize bionomical types of a rocky intertidal zone. It has been shown that the distribution of life forms is determined by the geomorphological peculiarities of the surveyed intertidal areas. A brief critical historical review has been provided of the terms bionomy and bionomical type.     

The death of birds on the sea coast of northeastern Sakhalin Island

The taxonomical composition of dead birds found on the northeastern coast of Sakhalin Island and the causes of their death were studied. Sites with high, average, and low concentration of dead birds were identified. The period of highest mortality of birds (July–August) coincided with the beginning of massive migrations of birds and large numbers of young birds after termination of the nesting season. Collection of bird remains in periods of bird migrations and breeding, in addition to other methods of ornithological research (visual observations, fowling, shooting), can provide useful information on the avifauna and ecological state of the investigated region.     

Functional Role of Large Organisms in Intertidal Communities: Community Effects and Ecosystem Function

In marine soft sediments, large organisms are potentially important players in the nonlinear interactions that occur among animals, their food, and their chemical environment, all of which influence the contribution of benthos to ecosystem function. We investigated the consequences of removing large individuals of two functionally contrasting benthic communities on nutrient regeneration, microphyte standing stock, and macrobenthic community composition. The experiment was conducted at two adjacent sites that were physically similar but biologically different, one dominated by large deposit feeders and the other by large suspension feeders. Chemical fluxes were measured in experimental plots, and sediments were sampled to assess changes in macrofauna, sediment grain size, organic content, and microphyte standing stock. Our results demonstrate that the removal of large suspension feeders or deposit feeders influenced the flux of nitrogen and oxygen, surficial sediment characteristics, and community composition. In the deposit-feeder community, interactions between nutrient regeneration and grazing highlight important feedbacks between large macrofauna and biogeochemical processes and production by microphytes, indicating that the loss of large infauna driven by increased rates of anthropogenic disturbance may lead to functional extinction and cause shifts in community structure and ecosystem performance.     

Spawning migration and redd construction of Sakhalin taimen, Hucho perryi (Salmonidae) on northern Hokkaido Island, Japan

Spatial and temporal patterns of redd construction by Sakhalin taimen, Hucho perryi , were studied in small streams on northern Hokkaido, Japan. Spawning took place in late April with close relation to discharge patterns. Observed redd size (mean ± 95% C.I.) was 145 ± 11·8 cm in length and 84 ± 5·8 cm in width. The number of egg pockets per redd was either one or two, which is fewer than that of other salmonids reported in the literature. Spawning ground distributions in 1991 and 1992 were similar to each other in terms of the distribution mean and dispersion of the redds. Unlike other salmonids Sakhalin taimen probably constructed multiple redds during one spawning season.     

An examination of species dispersion patterns along the intertidal gradient on Macquarie Island (sub-Antarctica) using a restricted occupancy model

It has been widely held that intertidal zonation boundaries and the tidal emersion levels are causally related: the critical tidal level hypothesis. In order to evaluate this hypothesis, the dispersion patterns of species boundaries on the intertidal rocky shores of Macquarie Island (sub-Antarctica) were examined using a restricted occupancy model to test the null hypothesis that the observed species were randomly dispersed along the tidal emersion gradient. Subsequently this investigation demonstrated that the intertidal species boundaries on Macquarie Island shores were randomly dispersed with respect to the tidal emersion gradient. Hence no prima facie evidence was found to support the critical tidal level hypothesis. This suggests that tidal emersion is not a significant factor structuring intertidal communities on Macquarie Island.     

Changes in the macrozoobenthos of the intertidal zone at Helgoland (German Bight, North Sea): a survey of 1984 repeated in 2002

Changes in the presence and absence of invertebrates as well as in species conspicuousness were documented in a rocky intertidal community based on surveys in 1984 and 2002. In 2002 six vertically and/or morphologically different stations of an intertidal platform were sampled. Five of these six habitats had already been surveyed in 1984. Replicating precisely the method of the first assessment, presence/absence changes as well as changes in species conspicuousness of 83 invertebrate species were documented, indicating that this intertidal community changed considerably during the 18-year interval. Compared with the study in 1984, 27 species newly appeared, whereas 32 species disappeared. Furthermore, 16 species increased in conspicuousness, whereas eight invertebrates decreased. The total number of species in 2002 was 154 versus 158 in 1984. Although algal species were not recorded as thoroughly as invertebrates, a massive decline in cover of Halidrys siliquosa was noted. Conversely, two invasive algal species became established after 1984, Sargassum muticum (since 1988), a cosmopolitan fucoid alga that prefers shallow subtidal areas for colonization, and Mastocarpus stellatus (introduction in the 1980s) that particularly colonized areas in the mid intertidal. In 1984 the mid intertidal zone was dominated by the brown alga Fucus serratus, whereas in 2002 the blue mussel Mytilus edulis and the periwinkle Littorina littorea were the most conspicuous organisms. Annual mean sea surface temperature (BAH measurements) warmed by 1.1°C over the past four decades. Range-related community shifts, introductions of non-indigenous species and the input of pollutants, are considered to explain long-term ecological changes in the invertebrate community at Helgoland.     

Reproduction of Pacific Salmon (Oncorhynchus) in Rivers Flowing into Terpeniya Bay (Sakhalin Island)

Journal of Ichthyology - The conditions for the reproduction of Pacific salmon of the Oncorhynchus genus in rivers flowing into Terpeniya Bay were assessed. The differences between the rivers of...     

广东上川岛潮间带软体动物的分布

对上川岛潮间带软体动物进行了采集调查,共鉴定软体动物172种,分属53科。其中瓣鳃纲20科81种,占总数47．09％,腹足纲33科91种,占总数52．91％。分析表明,其区系特点是以南海亚热带-热带种和东海、南海亚热带种为主要成分。     

崇明岛稻田三种种植方式下中小型土壤动物群落多样性

平陆运河是西部陆海新通道的一项重要工程,茅尾海是平陆运河的重要支撑节点。本次调查潮间带大型底栖动物群落,在评估茅尾海生态环境质量的同时,又积累本海域大型底栖动物基线数据,为平陆运河建设期、运营期的科学管理提供科学数据支撑。于2020年10月和2021年1月、4月、7月,在钦州茅尾海东部岸线设置4个采样断面,分别是仙岛公园、沙环村、滨海公园和康王庙村,按照《海洋调查规范》(GB 12763.6-2007)的要求对潮间带大型底栖动物进行采样调查和物种分类鉴定;分析大型底栖动物群落组成、优势种组成及生物多样性指数。调查研究结果表明,茅尾海潮间带大型底栖动物以节肢动物为主,物种占比超过41%,个体数占比超过87%,优势种(IRI > 1 000)有麦克碟尾虫(Discapseudes mackiei)、台湾泥蟹(Ilyoplax formosensis)、隆背大眼蟹(Macrophthalmus convexus)和四齿大额蟹(Metopograpsus quadridentatus),但优势种在4个断面分布不均,仅麦克碟尾虫出现在各断面;主要种(100 ≤ IRI < 1 000)有27种,其中仅扁平拟闭口蟹(Paracleistostoma depressum)、背毛小头虫(Notodasus sp.)出现在各断面;常见种(10 ≤ IRI < 100)有19种,稀有种(IRI < 10)有8种,它们均分布不均;辛普森多样性指数(D)和香农多样性指数(H?)分别为0.435(0.183 ~ 0.704)和1.506(0.747 ~ 2.256),显著低于2009年相应指标,P值分别为0.004和0.048;Pielou均匀度指数(J)均值为0.475(0.223 ~ 0.696),与2009年的Pielou均匀度指数(J)没有显著差异(P = 0.109)。综合丰度-生物量曲线(ABC曲线)、香农多样性指数(H?)、大型底栖动物污染指数(IMP)推断茅尾海目前整体海域生态环境处于中等污染水平。综合上述指标,认为目前茅尾海海域整体生态环境已属于中等程度污染。本次调查建立的茅尾海潮间带大型底栖动物数据库,将为未来平陆运河的生态建设和科学运营提供支撑。     

Immediate Effects of Experimental Human Trampling on Mid-Upper Intertidal benthic Invertebrates at the Asinara Island MPA (NW Mediterranean)

To assess potential risks of human visitation to ecological communities, the immediate effects of human trampling were investigated experimentally on small invertebrates inhabiting mid-upper intertidal hard bottoms covered by algae. Two different experimental intensities of trampling (60 and 120 footsteps) and controls (with no trampling) were applied to quadrats 20×20 cm in size (experimental area), within the two ‘no-entry, no-take’ zones of the Asinara Island MPA (Italy, Mediterranean Sea). One day after trampling ended, samples of benthic fauna were collected and the animals attributed to macrofaunal and meiofaunal components. Analyses of variance on the nine most common taxa of macrofauna identified significant higher abundance of bivalves, gammarid amphipods, polychaetes, isopods, oligochaetes in controls than in trampled plots. For nematodes, polychaetes, ostracods, oligochaetes, bivalves, acari, caprellid amphipods and tanaids a significant higher abundance of meiofaunal animals was found in controls than in trampled areas. Although no information on recovery is available, these results suggest that macrofaunal and meiofaunal taxa are vulnerable to this type of disturbance.     

Microbian Indication of Pollution of the Coastal Zone of the Sea of Okhotsk and Avacha Bay

The results of microbiological analysis of a number of microorganisms of various ecological–trophic groups in plankton microbial communities of some water areas of the Sea of Okhotsk and Avacha Bay are presented. The data were compared to the hydrochemical parameters (temperature, salinity, BOD₅, dissolved oxygen, phosphates, organic phosphate, detergents) determined simultaneously. The microbian indication method is used for express assessment of water pollution of the surveyed areas. The data demonstrated that Avacha Bay was subjected to heavier anthropogenic impact than the water areas of the ports of Kholmsk and Magadan.     

The size composition of the pelagic eggs of walleye pollack <Emphasis Type="Italic">Theragra chalcogramma</Emphasis> in spawning areas of the northern Sea of Okhotsk

The data on the size composition of the pollack developing eggs of walleye pollack collected in the northern Sea of Okhotsk in 2001 during mass spawning are given. The eggs caught in western Kamchatka and in Shelikhov Bay had the greatest diameter; they were somewhat less in the northern Okhotsk Sea area; and the smallest eggs were found in eastern Sakhalin. The clinal variability of the size composition of walleye pollack eggs was observed in the northern Sea of Okhotsk, and in the western and eastern parts it had a local pattern. Parameters such as spawning female size composition, temperature, and salinity, as well their influence on the size composition of eggs, were considered.Original Russian Text Copyright © 2004 by Biologiya Morya, Ovsyannikov.     

Sublittoral Protistan Communities of the Shores of the Sea of Cantabria (Bay of Biscay)

The composition of the protist communities of three coastal areas of the Sea of Cantabria were studied, and the seasonal variation of the larger groups of these organisms described, with respect to the productivity. Also, the annual dynamics of consumption and degradation of organic matter achieved by the ciliate species were analyzed.