6 resultados para Design time
em Publishing Network for Geoscientific
Resumo:
Using peridotite drilled during Ocean Drilling Program Leg 209, a series of enrichment cultures were initiated on board the ship to stimulate microbially enhanced dissolution of olivine. Dissolution was estimated by measured changes in dissolved Li and Si in the media through time (up to 709 days). The results suggest that there was no significant difference between the amounts of dissolved Li and Si in most of the inoculated microbial cultures compared to the control cultures. Alternative explanations for this are that 1. No microbes are living in the culture tubes that can affect the dissolution rates of olivine, 2. The control cultures have microbes effecting the dissolution of olivine as well as the inoculated cultures, 3. Not enough time has passed to build up a large enough microbial population to effect the dissolution of the olivine in the culture tubes, 4. Microbes act to suppress dissolution of olivine instead of enhancing dissolution, and 5. Abiotic dissolution overshadows microbially enhanced dissolution. Further work is required to test these alternatives.
Resumo:
These data form the basis of an analysis of a prevalent research bias in the field of ocean acidification, notably the ignoring of natural fluctuations and gradients in the experimental design. The data are extracted from published work and own experiments.
Resumo:
This paper describes seagrass species and percentage cover point-based field data sets derived from georeferenced photo transects. Annually or biannually over a ten year period (2004-2015) data sets were collected using 30-50 transects, 500-800 m in length distributed across a 142 km**2 shallow, clear water seagrass habitat, the Eastern Banks, Moreton Bay, Australia. Each of the eight data sets include seagrass property information derived from approximately 3000 georeferenced, downward looking photographs captured at 2-4 m intervals along the transects. Photographs were manually interpreted to estimate seagrass species composition and percentage cover (Coral Point Count excel; CPCe). Understanding seagrass biology, ecology and dynamics for scientific and management purposes requires point-based data on species composition and cover. This data set, and the methods used to derive it are a globally unique example for seagrass ecological applications. It provides the basis for multiple further studies at this site, regional to global comparative studies, and, for the design of similar monitoring programs elsewhere.
Resumo:
In 1990, a benthic component to the DYFAMED (dynamics of fluxes in the Mediterranean) program, the DYFAMED-BENTHOS survey, was established to investigate the possible coupling of benthic to pelagic processes at a permanent station in >2700 m water depth, 52 km off Nice, France. Surface sediment was first sampled at different periods of the year to assess the importance of the biological compartment (particularly metazoan meiofauna) and its relation to seasonally varying particulate matter input to the sea floor (estimated by measuring surface sediment particle size and porosity, as well as chloroplastic pigments, organic carbon, nitrogen and calcium carbonate contents). Beginning in 1993, surface sediment was sampled at an average interval of 1.4 months for over five consecutive years using multicorers. Biogeochemical techniques such as deployments of a free-vehicle benthic respirometer and a near-bottom sediment trap, along with analyses of sediment vertical profiles for dissolved oxygen, nutrients and dissolved metals in the porewater, were developed in conjunction with more extensive biological analyses to characterize the recycling of organic matter, and ultimately increase our understanding of the oceanic carbon cycle. This article provides the scientific background and motivation for the development of the on-going DYFAMED-BENTHOS survey, the general characteristics of the benthic site, as well as a detailed description of the sampling design applied from late 1990-2000.
Resumo:
Data were collected during various groundfish surveys carried out by IFREMER from October to December between 1997 and 2011, on the eastern continental shelf of the Bay of Biscay and in the Celtic Sea (EVHOE series). The sampling design was stratified according to latitude and depth. A 36/47 GOV trawl was used with a 20 mm mesh codend liner. Haul duration was 30 minutes at a towing speed of 4 knots. Fishing was restricted to daylight hours. Catch weights and catch numbers were recorded for all species and body size measured. The weights and numbers per haul were transformed into abundances per km**2 by considering the swept area of a standard haul (0.069 km**2).