Marine microplankton diversity database

Many macroecological theories have been developed to study the diversity on our planet. All these theories require the existence of consistent databases to test their predictions. In this work, we compiled a data set of marine microplankton species abundances at 788 stations with an extensive geographical coverage. Data were collected on different oceanographic cruises between 1992 and 2002. This database consists of abundances (cells/mL) for each species at each station and depth, together with estimates of the biomass and biovolume for each species. One of the key strengths in this database is that species identifications were made by the same taxonomist, which provides greater strength to the collection and ensures that estimates of species diversity are reliable. Environmental information has also been compiled at each station (chlorophyll, temperature, photosynthetically active radiation [PAR], nutrients) in order to have a characterization of the study area and to be used in studies on the environmental and biological controls of marine biodiversity.

Evaluating The Ribosomal Internal Transcribed Spacer (ITS) as a Candidate Dinoflagellate Barcode Marker

DNA barcoding offers an efficient way to determine species identification and to measure biodiversity. For dinoflagellates, an ancient alveolate group of about 2000 described extant species, DNA barcoding studies have revealed large amounts of unrecognized species diversity, most of which is not represented in culture collections. To date, two mitochondrial gene markers, Cytochrome Oxidase I (COI) and Cytochrome b oxidase (COB), have been used to assess DNA barcoding in dinoflagellates, and both failed to amplify all taxa and suffered from low resolution. Nevertheless, both genes yielded many examples of morphospecies showing cryptic speciation and morphologically distinct named species being genetically similar, highlighting the need for a common marker. For example, a large number of cultured Symbiodinium strains have neither taxonomic identification, nor a common measure of diversity that can be used to compare this genus to other dinoflagellates.

Valuing conservation benefits of an offshore marine protected area

Increasing anthropogenic pressure in the offshore marine environment highlights the need for improved management and conservation of offshore ecosystems. This study scrutinises the applicability of a discrete choice experiment to value the expected benefits arising from the conservation of an offshore sandbank in UK waters. The valuation scenario refers to the UK part of the Dogger Bank, in the southern North Sea, and is based on real-world management options for fisheries, wind farms and marine protection currently under discussion for the site. It is assessed to what extent the general public perceive and value conservation benefits arising from an offshore marine protected area. The survey reveals support for marine conservation measures despite the general public’s limited prior knowledge of current marine planning. Results further show significant values for an increase in species diversity, the protection of certain charismatic species and a restriction in the spread of invasive species across the site. Implications for policy and management with respect to commercial fishing, wind farm construction and nature conservation are discussed.

Effects of elevated CO2 and temperature on an intertidal meiobenthic community

In the near future, the marine environment is likely to be subjected to simultaneous increases in temperature and decreased pH. The potential effects of these changes on intertidal, meiofaunal assemblages were investigated using a mesocosm experiment. Artificial Substrate Units containing meiofauna from the extreme low intertidal zone were exposed for 60 days to eight experimental treatments (four replicates for each treatment) comprising four pH levels: 8.0 (ambient control), 7.7 & 7.3 (predicted changes associated with ocean acidification), and 6.7 (CO2 point-source leakage from geological storage), crossed with two temperatures: 12 °C (ambient control) and 16 °C (predicted). Community structure, measured using major meiofauna taxa was significantly affected by pH and temperature. Copepods and copepodites showed the greatest decline in abundance in response to low pH and elevated temperature. Nematodes increased in abundance in response to low pH and temperature rise, possibly caused by decreased predation and competition for food owing to the declining macrofauna density. Nematode species composition changed significantly between the different treatments, and was affected by both seawater acidification and warming. Estimated nematode species diversity, species evenness, and the maturity index, were substantially lower at 16 °C, whereas trophic diversity was slightly higher at 16 °C except at pH 6.7. This study has demonstrated that the combination of elevated levels of CO2 and ocean warming may have substantial effects on structural and functional characteristics of meiofaunal and nematode communities, and that single stressor experiments are unlikely to encompass the complexity of abiotic and biotic interactions. At the same time, ecological interactions may lead to complex community responses to pH and temperature changes in the interstitial environment

Valuation of ecological and amenity impacts of an offshore windfarm as a factor in marine planning

Integrated marine planning, which must take into consideration environmental and social impacts, is being introduced widely in Europe, the USA, Australia and elsewhere. Installation of offshore windfarms creates impacts both on local marine ecosystems and the view of the seascape and is one of multiple activities in the marine area that must be addressed by marine planning. The impacts on people's values (and hence welfare) of changes in ecology and amenity that could arise from the installation of a windfarm in the Irish Sea were assessed using a discrete choice experiment administered through an online survey. The ecological changes investigated were: increased species diversity resulting from artificial reef effects, and the effect of electromagnetic fields from subsea cables on marine life; whilst the amenity change was the visibility of offshore turbines from land. Respondents expressed preferences for ecological improvements but had less clear preferences regarding the height and visibility of the turbines. In particular distance decay effects were observed with respondents further away from the coast being less concerned about visual impact created by offshore turbines. Understanding ecological and amenity impacts and how they are valued by people can support the decisions made within marine planning and licensing.

Biological Communities at Marine Shallow-Water Vent and Seep Sites

The review compiles, for the first time, data on the communities at 62 shallow-water hydrothermal vent and cold seep sites. ‘Shallow sites’ are defined as sites no deeper than 200 m. The communities at these sites are also compared with communities in reducing sediments at similar depths. Below 200 m, vent and seep obligate species tend to dominate the fauna living in areas where reducing fluids are released from the seabed. At the shallow sites, vent and seep obligate species of fauna are rare, only eight having being reported from shallow vents. No definite seep obligates have been found. Shallow vents and seeps are colonized by communities that consist of a subset of the background fauna, especially those species that are less sensitive to hydrogen sulphide toxicity. Conversely the zones directly surrounding shallow vent and seeps sites with varied topography, substrate type and food supply, often have a higher species diversity than the background area. The reasons for these differences are discussed.