Technical Reports
Permanent URI for this collectionhttps://hdl.handle.net/1969.6/90022
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Browsing Technical Reports by Author "Baguley, Jeffrey G."
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Item Cruise Report for Deepwater Sediment Sampling Cruise M/V IRISH: Leg 1, 29 May to 10 June 2014, to Assess Potential Benthic Impacts from the Deepwater Horizon (DWH) Oil Spill(2015-08) Cooksey, Cynthia; Baguley, Jeffrey G.; Montagna, Paul A.To meet the objectives of the Deep Benthic Work Plan Addendum, a cruise was conducted to assess potential effects of the Deepwater Horizon (DWH) oil spill on deep-sea (>200 m) sediments and resident benthic fauna. Leg 1 of the cruise was conducted on the M/V IRISH, 29 May – 10 June 2014, under the auspices of the DWH/Natural Resource Damage Assessment (NRDA) Deepwater Benthic Communities Technical Working Group. A related deep-sea benthic sampling effort, M/V IRISH: Leg 2, was conducted June 14 – 28, 2014 and will be reported elsewhere. Only Leg 1 information is included in this document. A total of 2452 physical samples were collected from 56 deep-sea stations for the analysis of various biotic and abiotic environmental variables. Stations were included at near-field sites where DWH-related oil was measured at elevated levels during prior Response efforts, that were in paths of possible oil exposure based on subsurface trajectory-model predictions, and that serve as anticipated reference sites. At each station, a multi-corer (12 core system) was used to collect sediment samples for analysis of macrofauna, meiofauna, hydrocarbons, metals, and other basic sediment properties (total carbon, total organic carbon, total inorganic carbon, total nitrogen, grain size). Additional samples for sediment toxicity testing were collected at 12 of the 56 stations. A CTD with a dissolved-oxygen (DO) sensor also was deployed to obtain water-column profiles of salinity, temperature, DO, pH, and depth. The present cruise report provides a summary of sampling activities. Conclusions about the potential spatial extent of oil exposure, persistence of oil exposure over time, or resulting biological impacts based on these samples cannot be drawn until ongoing sample analyses are completed.Item Deepwater Horizon Oil Spill: Assessment of Potential Impacts on the Deep Soft-Bottom Benthos - Interim Data Summary Report(2013-02) Montagna, Paul A.; Baguley, Jeffrey G.; Cooksey, Cynthia; Hyland, Jeffrey L.A study was initiated in May 2011, under the direction of the Deepwater Horizon (DWH) Natural Resource Damage Assessment (NRDA) Deepwater Benthic Communities Technical Working Group (NRDA Deep Benthic TWG), to assess potential impacts of the DWH oil spill on sediments and resident benthic fauna in deepwater (> 200 meters) areas of the Gulf. Key objectives of the study were to complete the analysis of samples from 65 priority stations sampled in September-October 2010 on two DWH Response cruises (Gyre and Ocean Veritas) and from 38 long-term monitoring sites (including a subset of 35 of the original 65) sampled on a follow-up NRDA cruise in May-June 2011. The present progress report provides a brief summary of results from the initial processing of samples from fall 2010 priority sites (plus three additional historical sites). Data on key macrofaunal, meiofaunal, and abiotic environmental variables are presented for each of these samples and additional maps are included to depict spatial patterns in these variables throughout the study region. The near-field zone within about 3 km of the wellhead, where many of the stations showed evidence of impaired benthic condition (e.g. low taxa richness, high nematode/harpacticoid-copepod ratios), also is an area that contained some of the highest concentrations of total petroleum hydrocarbons (TPH), total polycyclic aromatic hydrocarbons (total PAHs), and barium in sediments (as possible indicators of DWH discharges). There were similar co-occurrences at other sites outside this zone, especially to the southwest of the wellhead out to about 15 km. However, there also were exceptions to this pattern, for example at several farther-field sites in deeper-slope and canyon locations where there was low benthic species richness but no evidence of exposure to DWH discharges. Such cases are consistent with historical patterns of benthic distributions in relation to natural controlling factors such as depth, position within canyons, and availability of organic matter derived from surface-water primary production.Item Restoration in Place Strategy for the Deep-sea Soft-Bottom Benthos: Long-term Monitoring to Support Restoration Efforts(2017-05) Montagna, Paul A.; Baguley, Jeffrey G.; Cooksey, Cynthia