00706nas a2200181   4500008004100000245013700041210006900178300001400247490000700261100002000268700001600288700001700304700001700321700002100338700001500359700001300374856013700387       2004                        eng d00aChanges in structural and functional diversity of nematode communities during a spring phytoplankton bloom in the southern North Sea0 aChanges in structural and functional diversity of nematode commu  a281–2920 v521 aVanaverbeke, J.1 aSteyaert, M1 aSoetaert, K.1 aRousseau, V.1 aVan Gansbeke, D.1 aParent, J.1 aVincx, M  uhttps://nematoda.myspecies.info/content/changes-structural-and-functional-diversity-nematode-communities-during-spring-phytoplankton03689nas a2200205   4500008004100000245009700041210006900138260006600207300001200273490000800285520292600293653001403219653001703233653002903250653002603279100001703305700001603322700001203338856013303350       2002                        eng d00aSize and shape of ocean margin nematodes: morphological diversity and depth-related patterns0 aSize and shape of ocean margin nematodes morphological diversity  aNORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANYbINTER-RESEARCH  a179-1930 v2423 aWe studied the composition and variation of nematode body size as a function of nematode depth in the sediment and water depth at 18 stations, ranging from 137 to 4951 m depth, along the Galician margin (NE Atlantic). The analysis is based on more than 10 000 individuals and demonstrates that nematodes have adapted mainly in response to the vertical changing conditions in the sediment. Nematode length and width are similar in the upper 0.5 cm of sediment at all stations, but differ greatly as their depth in the sediment increases. The observed trends are consistent with an adaptation to changing oxygen concentrations in the sediments. In lower slope and abyssal plain stations, oxygen decreases gradually until depletion at about 5 cm depth, and nematode body width decreases concurrently, resulting in higher oxygen absorption efficiency per unit of volume. On the shelf and in the canyons, sediments become anoxic at short distances below the sediment-water interface, and more than 50% of the nematodes are present in the anoxic part of the sediment. Here, mean nematode length increases as their depth in the sediment increases. This may result in increased mobility, which enables the organisms to migrate between anoxic patches of food and parts of the sediment where oxygen is available and/or the ability to bridge the gap between oxic and anoxic patches with their body. Order of magnitude calculation shows that in shelf sediments, the chemosynthetic bacterial production, which accompanies the oxidation of reduced substances, can not fulfill the feeding requirements of nematodes in the anoxic zone. The different size adaptations with sediment depth in shallow as compared to deep stations combined with deeper penetration of nematodes into the sediment at shallow water depth cause the observed pattern of miniaturization with increasing water depth. We conclude that nematode size distribution is determined by food availability. However, organic matter, as a food source, is not directly responsible,,as a limiting resource, but indirectly because its respiration generates reduced conditions in the sediment. Within the smaller size range (<500 mum length), there are 2 clearly distinct morphological types, which, to a certain extent, impart a taxonomic division. Similar findings at other localities suggest that this is a common feature of nematodes from ocean margin areas. One group consists of corpulent nematodes, which are less than 15 times as long as wide; most prominent in this group are members of the order of the Desmoscolecida. The other group contains significantly more slender nematodes and comprises a large variety of nematode taxa. We hypothesize that this duality in nematode design reflects an ecological adaptation designed to meet the conflicting requirements of either increased mobility (slender) or reduced vulnerability to predation (corpulent) at these small sizes.10anematodes10aocean margin10asediment biogeochemistry10asize-depth hypothesis1 aSoetaert, K.1 aMuthumbi, A1 aHEIP, C  uhttps://nematoda.myspecies.info/content/size-and-shape-ocean-margin-nematodes-morphological-diversity-and-depth-related-patterns00519nas a2200121   4500008004100000245010300041210006900144300001400213490000800227100001700235700001200252856013300264       1995                        eng d00aNematode assemblages of deep-sea and shelf break sites in the North Atlantic and Mediterranean Sea0 aNematode assemblages of deepsea and shelf break sites in the Nor  a171–1830 v1251 aSoetaert, K.1 aHEIP, C  uhttps://nematoda.myspecies.info/content/nematode-assemblages-deep-sea-and-shelf-break-sites-north-atlantic-and-mediterranean-sea