3. Wochenbericht SO239

31.3.2015 - 5.4.201

1. Wochenbericht SO239

11.3.2015 - 22.3.201

4./5. Wochenbericht SO239

6.4.2015 - 18.4.201

Proteomic fingerprinting facilitates biodiversity assessments in understudied ecosystems: A case study on integrated taxonomy of deep sea copepods

Accurate and reliable biodiversity estimates of marine zooplankton are a prerequisite to understand how changes in diversity can affect whole ecosystems. Species identification in the deep sea is significantly impeded by high numbers of new species and decreasing numbers of taxonomic experts, hampering any assessment of biodiversity. We used in parallel morphological, genetic, and proteomic characteristics of specimens of calanoid copepods from the abyssal South Atlantic to test if proteomic fingerprinting can accelerate estimating biodiversity. We cross-validated the respective molecular discrimination methods with morphological identifications to establish COI and proteomic reference libraries, as they are a pre-requisite to assign taxonomic information to the identified molecular species clusters. Due to the high number of new species only 37% of the individuals could be assigned to species or genus level morphologically. COI sequencing was successful for 70% of the specimens analysed, while proteomic fingerprinting was successful for all specimens examined. Predicted species richness based on morphological and molecular methods was 42 morphospecies, 56 molecular operational taxonomic units (MOTUs) and 79 proteomic operational taxonomic units (POTUs), respectively. Species diversity was predicted based on proteomic profiles using hierarchical cluster analysis followed by application of the variance ratio criterion for identification of species clusters. It was comparable to species diversity calculated based on COI sequence distances. Less than 7% of specimens were misidentified by proteomic profiles when compared with COI derived MOTUs, indicating that unsupervised machine learning using solely proteomic data could be used for quickly assessing species diversity

DNA barcoding and cryptic diversity of deep-sea scavenging amphipods in the Clarion-Clipperton Zone (Eastern Equatorial Pacific)

The Clarion-Clipperton Zone (CCZ), located in the abyssal equatorial Pacific, has been subject to intensive international exploration for polymetallic nodule mining over the last four decades. Many studies have investigated the potential effects of mining on deep-sea ecosystems and highlighted the importance of defining environmental baseline conditions occurring at potential mining sites. However, current information on biodiversity and species distributions in the CCZ is still scarce and hampers the ability to effectively manage and reduce the potential impacts of mining activities. As part of the regulatory regimes adopted by the International Seabed Authority, concession holders are required to conduct an environmental impact assessment and gather baseline data on biodiversity and community structure in relation to their license areas. In the present study, we used an integrative molecular and morphological approach to assess species richness and genetic variation of deep-sea scavenging amphipods collected in two nodule-mining exploration areas (UK-1 and OMS-1 areas) and one Area of Particular Environmental Interest (APEI-6) in the eastern part of the CCZ. We analyzed the DNA sequences of the cytochrome c oxidase subunit I gene of 645 specimens belonging to ten distinct morphospecies. Molecular data uncover potential cryptic diversity in two investigated species, morphologically identified as Paralicella caperesca Shulenberger & Barnard, 1976 and Valettietta cf. anacantha (Birstein & Vinogradov, 1963). Our study highlights the importance of using molecular tools in conjunction with traditional morphological methods for modern biodiversity assessment studies, particularly to evaluate morphologically similar individuals and incomplete specimens. The results of this study can help determine species identity and ranges, information which can feed into environmental management

Revision of Brasilibathynellocaris Jakobi, 1972 (Copepoda: Harpacticoida: Parastenocarididae) with redefinition of the genus

Members of the genus Brasilibathynellocaris Jakobi, 1972 are typical neotropical Parastenocarididae. Their geographical distribution ranges from Central America to southern Brazil, with species occurring on both sides of the Andes mountain chain. The genus can be characterized and easily identified by the following characters: leg 4 with two strong spinules on anterior margin of coxa; exopod 1 (exp-1) short and with a proximal invagination on inner corner; leg 3 with exopod inwardly curved, ending in a long forceps formed by apophysis and thumb (both with a hyaline margin). In the present work we favour revalidation of Brasilibathynellocaris, arguing for its monophyly. Pararemaneicaris Jakobi, 1972 and Paraforficatocaris Jakobi, 1972 are new junior synonyms of Brasilibathynellocaris, as a result of transfer of their respective type species: Brasilibathynellocaris cuscatlanensis (Noodt, 1962) comb. nov., and Brasilibathynellocaris paranaensis (Jakobi, 1972) comb. nov. Two monophyletic species groups, together constituting Brasilibathynellocaris, are newly proposed and diagnosed: the Brasilibathynellocaris brasilibathynellae group and the Brasilibathynellocaris salvadorensis group. Neotypes are designated for B. brasilibathynellae and B. paranaensis. comb. n ov. Redescriptions are provided for all known species of Brasilibathynellocaris. © 2010 The Linnean Society of London

Unexpected high abyssal ophiuroid diversity in polymetallic nodule fields of the Northeast Pacific Ocean, and implications for conservation

The largest and commercially appealing mineral deposits can be found in the abyssal seafloor of the Clarion-Clipperton Zone (CCZ), a polymetallic nodule province, in the NE Pacific Ocean, where experimental mining is due to take place. In anticipation of deep-sea mining impacts, it has become essential to rapidly and accurately assess biodiversity. For this reason, ophiuroid material collected during seven scientific cruises from five exploration license areas within CCZ, one area protected from mining (APEI3, Area of Particular Environmental Interest) in the periphery of CCZ and the DIS-turbance and re-COLonisation (DISCOL) Experimental Area (DEA), in the SE Pacific Ocean, was examined. Specimens were genetically analysed using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI). Maximum Likelihood and Neighbour Joining trees were constructed, while four tree-based and distance-based methods of species delineation (ABGD, BINs, GMYC, mPTP) were employed to propose Secondary Species Hypotheses (SSHs) within the ophiuroids collected. The species delimitations analyses concordant results revealed the presence of 43 deep-sea brittle stars SSHs, revealing an unexpectedly high diversity and showing that the most conspicuous invertebrates in abyssal plains have been so far considerably under-estimated. The number of SSHs found in each area varied from 5 (IFREMER area) to 24 (BGR area), while 13 SSHs were represented by singletons. None of the SSHs was found to be present in all 7 areas, while the majority of species (44.2 %) had a single-area presence (19 SSHs). The most common species were Ophioleucidae sp. (Species 29), Amphioplus daleus (Species 2) and Ophiosphalma glabrum (Species 3), present in all areas except APEI3. The biodiversity patterns could be mainly attributed to POC fluxes that could explain the highest species numbers found in BGR (German contractor area) and UKSRL (UK contractor area) areas. The five exploration contract areas belong to a mesotrophic province, while in contrary the APEI3 is located in an oligotrophic province which could explain the lowest diversity as well as very low similarity with the other six study areas. Based on these results the representativeness and the appropriateness of APEI3 to meet its purpose of preserving the biodiversity of the CCZ fauna are questioned. Finally, this study provides the foundation for biogeographic and functional analyses that will provide insight into the drivers of species diversity and its role in ecosystem function

Unexpected high abyssal ophiuroid diversity in polymetallic nodule fields of the Northeast Pacific Ocean, and implications for conservation

The largest and commercially appealing mineral deposits can be found in the abyssal seafloor of the Clarion-Clipperton Zone (CCZ), a polymetallic nodule province, in the NE Pacific Ocean, where experimental mining is due to take place. In anticipation of deep-sea mining impacts, it has become essential to rapidly and accurately assess biodiversity. For this reason, ophiuroid material collected during seven scientific cruises from five exploration license areas within CCZ, one area protected from mining (APEI3, Area of Particular Environmental Interest) in the periphery of CCZ and the DIS-turbance and re-COLonisation (DISCOL) Experimental Area (DEA), in the SE Pacific Ocean, was examined. Specimens were genetically analysed using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI). Maximum Likelihood and Neighbour Joining trees were constructed, while four tree-based and distance-based methods of species delineation (ABGD, BINs, GMYC, mPTP) were employed to propose Secondary Species Hypotheses (SSHs) within the ophiuroids collected. The species delimitations analyses concordant results revealed the presence of 43 deep-sea brittle stars SSHs, revealing an unexpectedly high diversity and showing that the most conspicuous invertebrates in abyssal plains have been so far considerably under-estimated. The number of SSHs found in each area varied from 5 (IFREMER area) to 24 (BGR area), while 13 SSHs were represented by singletons. None of the SSHs was found to be present in all 7 areas, while the majority of species (44.2 %) had a single-area presence (19 SSHs). The most common species were Ophioleucidae sp. (Species 29), Amphioplus daleus (Species 2) and Ophiosphalma glabrum (Species 3), present in all areas except APEI3. The biodiversity patterns could be mainly attributed to POC fluxes that could explain the highest species numbers found in BGR (German contractor area) and UKSRL (UK contractor area) areas. The five exploration contract areas belong to a mesotrophic province, while in contrary the APEI3 is located in an oligotrophic province which could explain the lowest diversity as well as very low similarity with the other six study areas. Based on these results the representativeness and the appropriateness of APEI3 to meet its purpose of preserving the biodiversity of the CCZ fauna are questioned. Finally, this study provides the foundation for biogeographic and functional analyses that will provide insight into the drivers of species diversity and its role in ecosystem function

Coordinating sustained coastal and ocean observing efforts in Germany

Germany’s national ocean observing activities are carried out by multiple actors including governmental bodies, research institutions, and universities, and miss central coordination and governance. A particular strategic approach to coordinate and facilitate ocean research has formed in Germany under the umbrella of the German Marine Research Consortium (KDM). KDM aims at bringing together the marine science expertise of its member institutions and collectively presents them to policy makers, research funding organizations, and to the general public. Within KDM, several strategic groups (SGs), composed of national experts, have been established in order to strengthen different scientific and technological aspects of German Marine Research. Here we present the SG for sustained open ocean observing and the SG for sustained coastal observing. The coordination effort of the SG’s include (1) Representing German efforts in ocean observations, providing information about past, ongoing and planned activities and forwarding meta-information to data centers (e.g., JCOMMOPS), (2) Facilitating the integration of national observations into European and international observing programs (e.g. GCOS, GOOS, BluePlanet, GEOSS), (3) Supporting innovation in observing techniques and the development of scientific topics on observing strategies, (4) Developing strategies to expand and optimize national observing systems in consideration of the needs of stakeholders and conventions, (5) Contributing to agenda processes and roadmaps in science strategy and funding, and (6) Compiling recommendations for improved data collection and data handling, to better connect to the global data centers adhering to quality standards

Biological responses to disturbance from simulated deep-sea polymetallic nodule mining

Commercial-scale mining for polymetallic nodules could have a major impact on the deep-sea environment, but the effects of these mining activities on deep-sea ecosystems are very poorly known. The first commercial test mining for polymetallic nodules was carried out in 1970. Since then a number of small-scale commercial test mining or scientific disturbance studies have been carried out. Here we evaluate changes in faunal densities and diversity of benthic communities measured in response to these 11 simulated or test nodule mining disturbances using meta-analysis techniques. We find that impacts are often severe immediately after mining, with major negative changes in density and diversity of most groups occurring. However, in some cases, the mobile fauna and small-sized fauna experienced less negative impacts over the longer term. At seven sites in the Pacific, multiple surveys assessed recovery in fauna over periods of up to 26 years. Almost all studies show some recovery in faunal density and diversity for meiofauna and mobile megafauna, often within one year. However, very few faunal groups return to baseline or control conditions after two decades. The effects of polymetallic nodule mining are likely to be long term. Our analyses show considerable negative biological effects of seafloor nodule mining, even at the small scale of test mining experiments, although there is variation in sensitivity amongst organisms of different sizes and functional groups, which have important implications for ecosystem responses. Unfortunately, many past studies have limitations that reduce their effectiveness in determining responses. We provide recommendations to improve future mining impact test studies. Further research to assess the effects of test-mining activities will inform ways to improve mining practices and guide effective environmental management of mining activities