distant but shallower (2700 m). Several multiple-corer deployments at three stations within each ... more distant but shallower (2700 m). Several multiple-corer deployments at three stations within each area and the vertical sectioning of the sediment samples allowed the detailed study of horizontal and vertical meiofaunal distribution. Data analyses indicated differences between the two studied areas and among sediment horizons when richness and community structure at major taxa level were used, but these patterns do not stand for overall metazoan meiofaunal abundance. Nevertheless, nematode and copepod standing stocks follow diversity community patterns that could even indicate differences among stations of the same area. The results of this study suggest that meiofaunal richness and community structure are rather related to depth than distance to coast, exhibiting the well-known decreasing bathymetric trend even in an enclosed, event driven system.
Polymetallic nodules in deep-sea habitats of the Pacific Ocean will be subject to commercial expl... more Polymetallic nodules in deep-sea habitats of the Pacific Ocean will be subject to commercial exploitation in the near future but the potential effects of such mining activities on benthic life are difficult to assess. Here we present results from a recent revisit onboard RV SONNE (leg SO242/2) to the site of the “DISturbance and reCOLonization experiment” (DISCOL), a large scale benthic impact study initiated in 1989 in a polymetallic nodule area in the Peru Basin (tropical south-eastern Pacific). The area was artificially disturbed by a plow harrow to simulate manganese nodule extraction. In 2015, Meiofauna samples were collected and analysed at two different spatial scales in the framework of the JPI Oceans' programme ‘Ecological Aspects of Deep-Sea Mining’ to study the response and recovery rate of benthic faunal communities. At a macroscale, meiofauna densities and community composition were compared between two stations within the DISCOL experimental area (DEA) and three un...
Efforts to satisfy the current need for many high technology elements, such as copper, nickel and... more Efforts to satisfy the current need for many high technology elements, such as copper, nickel and yttrium from land-based sources are growing. Potential future sources of some of these elements include the deep sea manganese nodule fields of the Pacific, Atlantic, and Indian oceans. Large swathes of deep-sea seafloor are covered with high densities of 5 – 25 cm diameter nodules – agglomerations of manganese, iron, cobalt, copper, and other metals. In the 1980's these manganese fields were first seriously considered as mining targets, and the ''DISturbance and reCOLonization (DISCOL) experiment was started in the tropical Southeast Pacific, to simulate the likely environmental impacts of mining. In September 1989, 'RV SONNE', used a plough device to disturb the top sediment and to remove manganese nodules from the seafloor surface by burying them below the surface. 78 plough tracks of 8 – 16m width were made across a 10.8 km diameter circular area centered at 7°04...
Deep Sea Research Part I: Oceanographic Research Papers, 2021
Abstract The present investigation focuses on the Global Sea Mineral Resources contract area B4S0... more Abstract The present investigation focuses on the Global Sea Mineral Resources contract area B4S03 site in the Clarion-Clipperton Fracture Zone nodule fields. We investigated the sedimentary characteristics and the higher-taxon (order/class) and lower-taxon (family, morphospecies) diversity of the soft sediment macrobenthos with special focus on the dominant taxa (Isopoda, Polychaeta, Tanaidacea) in relation to nodule abundance. Across all analyses no consistent and/or significant differences between the two nodule-rich and the nodule free stations were found in terms of abiotic or biotic factors, suggesting that both habitat-types have similar sedimentary conditions and that macrofauna is represented by comparable densities and higher-taxon diversity across stations. Rarefaction/accumulation curves and sample coverage analysis shows that the current sampling effort was insufficient to characterize the B4S03 site diversity at morphospecies level but covered >90% of the diversity at the family level for the three dominant taxa. The high number of singletons encountered, the patchiness and low densities of the investigated taxa coupled to the logistically limited potential for replication per habitat/station, may point to under-sampling bias of the current study with the risk to underestimate species diversity and overestimate endemism. We recommend a more extensive sampling with the combination of molecular tools coupled with taxonomical expertise.
Understanding processes responsible for shaping biodiversity patterns on continental margins is a... more Understanding processes responsible for shaping biodiversity patterns on continental margins is an important requirement for comprehending anthropogenic impacts in these environments. Continental margins perform crucial functions which are mainly structured by hydrodynamic effects and surface primary productivity. However, to what extent these processes control benthic local and regional biodiversity remains unclear. In this study, we focused on two isobathic parallel transects to test if food resources arriving at the seafloor and hydrodynamic effects affect alpha and beta diversity at different depths in similar ways. We also examined the potential role of connectivity between both depths as a result of dispersal. This is the first study applying integrative approaches using molecular and morphological techniques in combination with environmental factors to unravel spatial variability and connectivity in relation to depth in the deep sea. Results revealed that high variability in ...
As part of the New Zealand government Ocean Survey 20/20 programme (OS 20/20, 2006–2013), samples... more As part of the New Zealand government Ocean Survey 20/20 programme (OS 20/20, 2006–2013), samples from the Chatham Rise and Challenger Plateau collected in 2007 were analysed to determine the effects of key environmental parameters, in particular sediment and water mass properties, on spatial changes in the community structure (abundance, diversity and community composition) of bathyal asellotan isopods. Benthic collections were obtained in austral autumn (May/June 2007) and included a total of 21 epibenthic sledge samples taken from the upper slope between 218 and 1239 m. Due to the contrasting environmental settings between the Chatham Rise and Challenger Plateau, in terms of surface productivity and habitat heterogeneity, we expected the abundance, regional (or gamma-) diversity and community composition of benthic isopods to significantly differ between the two regions, and furthermore local (or alpha-) diversity and abundance (density) to decrease with increasing depth. Consist...
The abyssal seafloor is a mosaic of highly diverse habitats that represent the least known marine... more The abyssal seafloor is a mosaic of highly diverse habitats that represent the least known marine ecosystems on Earth. Some regions enriched in natural resources, such as polymetallic nodules in the Clarion-Clipperton Zone (CCZ), attract much interest because of their huge commercial potential. Since nodule mining will be destructive, baseline data are necessary to measure its impact on benthic communities. Hence, we conducted an environmental DNA and RNA metabarcoding survey of CCZ biodiversity targeting microbial and meiofaunal eukaryotes that are the least known component of the deep-sea benthos. We analyzed two 18S rRNA gene regions targeting eukaryotes with a focus on Foraminifera (37F) and metazoans (V1V2), sequenced from 310 surface-sediment samples from the CCZ and other abyssal regions. Our results confirm huge unknown deep-sea biodiversity. Over 60% of benthic foraminiferal and almost a third of eukaryotic operational taxonomic units (OTUs) could not be assigned to a known...
distant but shallower (2700 m). Several multiple-corer deployments at three stations within each ... more distant but shallower (2700 m). Several multiple-corer deployments at three stations within each area and the vertical sectioning of the sediment samples allowed the detailed study of horizontal and vertical meiofaunal distribution. Data analyses indicated differences between the two studied areas and among sediment horizons when richness and community structure at major taxa level were used, but these patterns do not stand for overall metazoan meiofaunal abundance. Nevertheless, nematode and copepod standing stocks follow diversity community patterns that could even indicate differences among stations of the same area. The results of this study suggest that meiofaunal richness and community structure are rather related to depth than distance to coast, exhibiting the well-known decreasing bathymetric trend even in an enclosed, event driven system.
Polymetallic nodules in deep-sea habitats of the Pacific Ocean will be subject to commercial expl... more Polymetallic nodules in deep-sea habitats of the Pacific Ocean will be subject to commercial exploitation in the near future but the potential effects of such mining activities on benthic life are difficult to assess. Here we present results from a recent revisit onboard RV SONNE (leg SO242/2) to the site of the “DISturbance and reCOLonization experiment” (DISCOL), a large scale benthic impact study initiated in 1989 in a polymetallic nodule area in the Peru Basin (tropical south-eastern Pacific). The area was artificially disturbed by a plow harrow to simulate manganese nodule extraction. In 2015, Meiofauna samples were collected and analysed at two different spatial scales in the framework of the JPI Oceans' programme ‘Ecological Aspects of Deep-Sea Mining’ to study the response and recovery rate of benthic faunal communities. At a macroscale, meiofauna densities and community composition were compared between two stations within the DISCOL experimental area (DEA) and three un...
Efforts to satisfy the current need for many high technology elements, such as copper, nickel and... more Efforts to satisfy the current need for many high technology elements, such as copper, nickel and yttrium from land-based sources are growing. Potential future sources of some of these elements include the deep sea manganese nodule fields of the Pacific, Atlantic, and Indian oceans. Large swathes of deep-sea seafloor are covered with high densities of 5 – 25 cm diameter nodules – agglomerations of manganese, iron, cobalt, copper, and other metals. In the 1980's these manganese fields were first seriously considered as mining targets, and the ''DISturbance and reCOLonization (DISCOL) experiment was started in the tropical Southeast Pacific, to simulate the likely environmental impacts of mining. In September 1989, 'RV SONNE', used a plough device to disturb the top sediment and to remove manganese nodules from the seafloor surface by burying them below the surface. 78 plough tracks of 8 – 16m width were made across a 10.8 km diameter circular area centered at 7°04...
Deep Sea Research Part I: Oceanographic Research Papers, 2021
Abstract The present investigation focuses on the Global Sea Mineral Resources contract area B4S0... more Abstract The present investigation focuses on the Global Sea Mineral Resources contract area B4S03 site in the Clarion-Clipperton Fracture Zone nodule fields. We investigated the sedimentary characteristics and the higher-taxon (order/class) and lower-taxon (family, morphospecies) diversity of the soft sediment macrobenthos with special focus on the dominant taxa (Isopoda, Polychaeta, Tanaidacea) in relation to nodule abundance. Across all analyses no consistent and/or significant differences between the two nodule-rich and the nodule free stations were found in terms of abiotic or biotic factors, suggesting that both habitat-types have similar sedimentary conditions and that macrofauna is represented by comparable densities and higher-taxon diversity across stations. Rarefaction/accumulation curves and sample coverage analysis shows that the current sampling effort was insufficient to characterize the B4S03 site diversity at morphospecies level but covered >90% of the diversity at the family level for the three dominant taxa. The high number of singletons encountered, the patchiness and low densities of the investigated taxa coupled to the logistically limited potential for replication per habitat/station, may point to under-sampling bias of the current study with the risk to underestimate species diversity and overestimate endemism. We recommend a more extensive sampling with the combination of molecular tools coupled with taxonomical expertise.
Understanding processes responsible for shaping biodiversity patterns on continental margins is a... more Understanding processes responsible for shaping biodiversity patterns on continental margins is an important requirement for comprehending anthropogenic impacts in these environments. Continental margins perform crucial functions which are mainly structured by hydrodynamic effects and surface primary productivity. However, to what extent these processes control benthic local and regional biodiversity remains unclear. In this study, we focused on two isobathic parallel transects to test if food resources arriving at the seafloor and hydrodynamic effects affect alpha and beta diversity at different depths in similar ways. We also examined the potential role of connectivity between both depths as a result of dispersal. This is the first study applying integrative approaches using molecular and morphological techniques in combination with environmental factors to unravel spatial variability and connectivity in relation to depth in the deep sea. Results revealed that high variability in ...
As part of the New Zealand government Ocean Survey 20/20 programme (OS 20/20, 2006–2013), samples... more As part of the New Zealand government Ocean Survey 20/20 programme (OS 20/20, 2006–2013), samples from the Chatham Rise and Challenger Plateau collected in 2007 were analysed to determine the effects of key environmental parameters, in particular sediment and water mass properties, on spatial changes in the community structure (abundance, diversity and community composition) of bathyal asellotan isopods. Benthic collections were obtained in austral autumn (May/June 2007) and included a total of 21 epibenthic sledge samples taken from the upper slope between 218 and 1239 m. Due to the contrasting environmental settings between the Chatham Rise and Challenger Plateau, in terms of surface productivity and habitat heterogeneity, we expected the abundance, regional (or gamma-) diversity and community composition of benthic isopods to significantly differ between the two regions, and furthermore local (or alpha-) diversity and abundance (density) to decrease with increasing depth. Consist...
The abyssal seafloor is a mosaic of highly diverse habitats that represent the least known marine... more The abyssal seafloor is a mosaic of highly diverse habitats that represent the least known marine ecosystems on Earth. Some regions enriched in natural resources, such as polymetallic nodules in the Clarion-Clipperton Zone (CCZ), attract much interest because of their huge commercial potential. Since nodule mining will be destructive, baseline data are necessary to measure its impact on benthic communities. Hence, we conducted an environmental DNA and RNA metabarcoding survey of CCZ biodiversity targeting microbial and meiofaunal eukaryotes that are the least known component of the deep-sea benthos. We analyzed two 18S rRNA gene regions targeting eukaryotes with a focus on Foraminifera (37F) and metazoans (V1V2), sequenced from 310 surface-sediment samples from the CCZ and other abyssal regions. Our results confirm huge unknown deep-sea biodiversity. Over 60% of benthic foraminiferal and almost a third of eukaryotic operational taxonomic units (OTUs) could not be assigned to a known...
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Papers by Lidia Lins