02419nas a2200253   4500008004100000245016200041210006900203260008400272300001200356490000700368520147600375653001301851653001401864653001401878653001901892653001301911100001501924700002001939700001701959700001701976700001901993700001602012856013702028       2008                        eng d00aAn assessment of the spatial heterogeneity of environmental disturbance within an enclosed harbour through the analysis of meiofauna and nematode assemblages0 aassessment of the spatial heterogeneity of environmental disturb  a24-28 OVAL RD, LONDON NW1 7DX, ENGLANDbACADEMIC PRESS LTD ELSEVIER SCIENCE LTD  a565-5760 v773 aSignificant spatial heterogeneity in the abundance and composition of meiofaunal and nematode assemblages was described inside the Genoa-Voltri harbour (Genoa, Italy) in relation to variation in the main environmental variables. In harbour sediments characterized by low Eh values and high organic matter concentrations, total meiofauna abundance was lower (948 +/- 919 ind 10 cm(-2)), nematode individual biomass was higher (0.17 +/- 0.07 mu g C), kinorhynchs and tanaids were completely absent, and the nematode assemblage was dominated by the genera Terschellingia, Sabatieria (pulchra group) and Paracomesoma. In contrast, in sediment characterized by lower levels of organic pollution, meiofaunal abundance was higher (1085 737 ind 10 cm(-2)), nematode individual biomass was lower (0.11 +/- 0.04 mu g C), kinorhynchs and tanaids were present and the nematodes were dominated by the genera Desmodora, Daptonema, Anticoma and Halalaimus. Environmental disturbance as assessed by the analysis of meiofaunal and nematode assemblages and sediment environmental variables changed significantly over a scale hundreds of meters, but did not follow a gradient from the inner to the outer harbour. Analysis of nematode assemblages is proposed as a useful tool for the identification of environmental risk areas which may assist in the development of good planning, monitoring programmes and better management of harbour ecosystems. (c) 2007 Elsevier Ltd. All rights reserved.10aharbours10ameiofauna10anematodes10aorganic matter10asediment1 aMoreno, M.1 aFerrero, T., J.1 aGallizia, I.1 aVezzulli, L.1 aAlbertelli, G.1 aFabiano, M.  uhttps://nematoda.myspecies.info/content/assessment-spatial-heterogeneity-environmental-disturbance-within-enclosed-harbour-through-a03290nas a2200241   4500008004100000245014000041210006900181260008400250300001200334490000700346520232800353653002602681653002302707653001402730653003402744653003702778100001702815700001902832700002002851700002102871700001902892856013702911       2009                        eng d00aSpatial and seasonal variations in the ecological characteristics of the free-living nematode assemblages in a large microtidal estuary0 aSpatial and seasonal variations in the ecological characteristic  a24-28 OVAL RD, LONDON NW1 7DX, ENGLANDbACADEMIC PRESS LTD ELSEVIER SCIENCE LTD  a309-3220 v823 aThis study has determined the ways in which the density, number of species, species composition and trophic structure of free-living nematode assemblages in the subtidal waters of a large southern hemisphere microtidal estuary change spatially and seasonally, and has explored whether those four biotic characteristics are related to certain environmental factors. Based on data derived from samples collected seasonally at 12 sites throughout the estuary, the densities and number of species of nematodes decreased progressively with distance from estuary mouth, to reach a minimum at sites where salinities were most variable. and then increased slightly in the uppermost part of the estuary where salinities were least. Densities were also generally greatest in spring, due largely to increases in the abundance of epistrate-grazing species at this time and thus when the amount of primary food (microphytobenthos) peaked. The spatial distribution of the composition of the nematode assemblages was closely correlated with salinity and, to a lesser extent, grain-size composition and amount of particulate organic material (%POM) in the sediment. Although species composition changed sequentially along the estuary, the change was particularly pronounced between sites above and below the area where salinities started to decline markedly and become more variable and %POM increased markedly. This reflected, in particular, far greater abundances of Spirinia parasitifera at the six downstream sites and of Theristus sp. 1 at the six sites further upstream. Species composition underwent pronounced seasonal cyclical changes at all sites, presumably reflecting interspecific differences in the timing of peak reproduction and thus of recruitment. The trophic structure of the nematode assemblages changed both spatially and temporally in relation to the relative abundance of different food sources. Thus, for example, non-selective deposit feeders, such as Theristus sp. 1, dominated samples in the upper estuary, where %POM was by far the greatest, and was rare or absent at downstream sites. Conversely, epistrate grazers, such as species of the Chromadoridae, were most abundant at downstream sites in spring, when the density of the microphytobenthos reached its maximum. (C) 2009 Elsevier Ltd. All rights reserved.10aenvironmental factors10amicrotidal estuary10anematodes10anumber of species and density10aspecies and trophic compositions1 aHourston, M.1 aPotter, I., C.1 aWarwick, R., M.1 aValesini, F., J.1 aClarke, K., R.  uhttps://nematoda.myspecies.info/content/spatial-and-seasonal-variations-ecological-characteristics-free-living-nematode-assemblages-03129nas a2200277   4500008004100000245010300041210006900144260008500213300001200298490000700310520214500317653001802462653001902480653001602499653001402515653002202529653002502551100001902576700002102595700002502616700002502641700002102666700001302687700001802700856013302718       2009                        eng d00aBiodiversity patterns of free-living marine nematodes in a tropical bay: Cienfuegos, Caribbean Sea0 aBiodiversity patterns of freeliving marine nematodes in a tropic  a24-28 OVAL RD, LONDON NW1 7DX, ENGLANDbACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  a179-1890 v853 aSpatial and temporal biodiversity patterns of free-living marine nematodes were studied in Cienfuegos Bay, a tropical semi-enclosed basin in the Caribbean Sea. Taxonomic (to species level) and functional (biological trait) approaches were applied for describing the assemblage structure and relating it to abiotic environment based on a sampling scheme in six subtidal stations and three months. Biological trait approach added relevant information to species pattern regarding relationships between diversity patterns and the abiotic environment. The most common morphotypes were deposit feeding nematodes, with colonising abilities of 2-3 (in a scale from 1 to 5), tail conical cylindrical or filiforme and body slender; and their abundance were correlated with depth, organic matter and silt/clay fraction. In spite of a high turnover of species, functional diversity of assemblages did not change notably in space and time. A result probably due to sampling of the habitat pool of species and to low heterogeneity of the studied muddy bottoms. Chemical pollution (organic enrichment and heavy metals) and hydrodynamic regime possibly drove the biodiversity patterns. Spatial distribution of assemblages support the existence of two well differentiated basins inside the bay, the northern basin more polluted than the southern one. The low hydrodynamic regime would determine a poor dispersion of nematodes resulting in high spatial variance in the assemblage structure; and also the associated hypoxic conditions and pollutants in sediments can explain the dominance of tolerant nematode species such as Daptonema oxycerca, Sabatieria pulchra, Terschellingia gourbaultae, and Terschellingia longicaudata. A comparison of spatial-temporal patterns of biodiversity between Cienfuegos Bay and other semi-enclosed bays in temperate regions suggests several similarities: nematode assemblages are strongly influenced by anthropogenic disturbance, temporal trends are weak or overridden by spatial ones, and few cosmopolitan genera/species tolerant to pollution and hypoxic conditions are dominant. (C) 2009 Elsevier Ltd. All rights reserved.10aCaribbean Sea10amarine ecology10aMeiobenthos10anematodes10aspecies diversity10atropical environment1 aArmenteros, M.1 aRuiz-Abierno, A.1 aFernandez-Garces, R.1 aPerez-Garcia, J., A.1 aDiaz-Asencio, L.1 aVincx, M1 aDecraemer, W.  uhttps://nematoda.myspecies.info/content/biodiversity-patterns-free-living-marine-nematodes-tropical-bay-cienfuegos-caribbean-sea02770nas a2200253   4500008004100000245013000041210006900171260008400240300001200324490000700336520180700343653001102150653001402161653001402175653001402189653002002203653002202223100002702245700003002272700003202302700001802334700002702352856013702379       2006                        eng d00aComparison of nematode communities in Baltic and North Sea sublittoral, permeable sands - Diversity and environmental control0 aComparison of nematode communities in Baltic and North Sea subli  a24-28 OVAL RD, LONDON NW1 7DX, ENGLANDbACADEMIC PRESS LTD ELSEVIER SCIENCE LTD  a224-2380 v703 aThe structure of free-living nematode communities was investigated seasonally at two sandy locations representing typical shallow sublittotal, permeable environments of the North Sea and the Baltic Sea. At the Baltic study site the chlorophyll and organic carbon concentrations in the sediment were, on average, four times lower than at the North Sea. Highest nematode densities (1674-4100 ind. 10 cm(-2)) and a higher number of free-living nematode genera (66) were recorded in the North Sea (Baltic: 206-1227 ind. 10 cm(-2), 30 genera). Despite lower salinity and lower food availability the less dense and less diverse Baltic nematode community was similar in generic composition to the North Sea community. At the North Sea site, all trophic groups according to Wieser's classification were present with omnivores/predators, dominated by Viscosia, prevailing and followed by epistrate-feeders. In the food-limited Baltic community, non-selective deposit feeders (mainly Ascolaimus, Axonolaimus and Daptonema) and omnivores/predators dominated by Enoplolaimus were the most abundant trophic groups while selective deposit feeders were absent or their contribution was negligible. An analysis of the vertical generic distribution revealed highest diversity of the Baltic community in deeper sediment layers, below the sediment surface affected by ripple migration and near the interface of oxic and anoxic conditions. The diversity pattern in the North Sea sediment was more variable but generally showed high diversity in the upper centimetre of the sediment. These observations suggest that food supply and sediment oxygenation are the most important factors influencing the vertical pattern of nematode generic diversity in sublittoral, permeable sands. (c) 2006 Elsevier Ltd. All rights reserved.10aBaltic10adiversity10anematodes10aNorth Sea10apermeable sands10asublittoral sands1 aUrban-Malinga, Barbara1 aHedtkamp, Stefanie, I. C.1 avan Beusekom, Justus, E. E.1 aWiktor, Jozef1 aWeslawski, Jan, Marcin  uhttps://nematoda.myspecies.info/content/comparison-nematode-communities-baltic-and-north-sea-sublittoral-permeable-sands-diversity-a