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Title: Establishing benchmarks in compliance assessment for the ballast water management convention by port state control
Description: Cited By :2
Author: Wright, Welschmeyer

Title: A shipboard comparison of analytic methods for ballast water compliance monitoring
Description: Abstract Promising approaches for indicative analysis of ballast water samples have been developed that require study in the field to examine their utility for determining compliance with the International Convention for the Control and Management of Ships' Ballast Water and Sediments. To address this gap, a voyage was undertaken on board the RV Meteor, sailing the North Atlantic Ocean from Mindelo (Cape Verde) to Hamburg (Germany) during June 4–15, 2015. Trials were conducted on local sea water taken up by the ship's ballast system at multiple locations along the trip, including open ocean, North Sea, and coastal water, to evaluate a number of analytic methods that measure the numeric concentration or relative biomass of viable organisms according to two size categories (≥ 50 μm in minimum dimension: 7 techniques, ≥ 10 μm and < 50 μm: 9 techniques). Water samples were analyzed in parallel to determine whether results were similar between methods and whether rapid, indicative methods offer comparable results to standard, time- and labor-intensive detailed methods (e.g. microscopy) and high-end scientific approaches (e.g. flow cytometry). Several promising indicative methods were identified that showed high correlation with microscopy, but allow much quicker processing and require less expert knowledge. This study is the first to concurrently use a large number of analytic tools to examine a variety of ballast water samples on board an operational ship in the field. Results are useful to identify the merits of each method and can serve as a basis for further improvement and development of tools and methodologies for ballast water compliance monitoring.
Author: Bradie, Broeg, Gianoli, He, Heitmüller, Curto, Nakata, Rolke, Schillak, Stehouwer, Vanden Byllaardt, Veldhuis, Welschmeyer, Younan, Zaake, Bailey

Title: Detection of UV-treatment effects on plankton by rapid analytic tools for ballast water compliance monitoring immediately following treatment
Description: Abstract Non-indigenous species seriously threaten native biodiversity. To reduce establishments, the International Maritime Organization established the Convention for the Control and Management of Ships' Ballast Water and Sediments which limits organism concentrations at discharge under regulation D-2. Most ships will comply by using on-board treatment systems to disinfect their ballast water. Port state control officers will need simple, rapid methods to detect compliance. Appropriate monitoring methods may be dependent on treatment type, since different treatments will affect organisms by a variety of mechanisms. Many indicative tools have been developed, but must be examined to ensure the measured variable is an appropriate signal for the response of the organisms to the applied treatment. We assessed the abilities of multiple analytic tools to rapidly detect the effects of a ballast water treatment system based on UV disinfection. All devices detected a large decrease in the concentrations of vital organisms ≥ 50 μm and < 10 μm organisms (mean 82.7–99.7% decrease across devices), but results were more variable for the ≥ 10 to < 50 μm size class (mean 9.0–99.9% decrease across devices). Results confirm the necessity to choose tools capable of detecting the damage inflicted on living organisms, as examined herein for UV-C treatment systems.
Author: Bradie, Gianoli, He, Curto, Stehouwer, Veldhuis, Welschmeyer, Younan, Zaake, Bailey

Title: Bacterial production and the sinking flux of particulate organic matter in the subarctic Pacific,
Description: We measured bacterial production and estimated the carbon consumption by bacteria in the mesopelagic zone (80-600 m) in the subarctic Pacific during May and August. Bacterial production was measured by leucine and thymidine incorporation. The two methods gave similar results. Bacterial production in the euphotic zone accounted for about 13% of primary production and in the whole water column for 20% (0-600 m). To bracket bacterial carbon consumption we made a lowest and highest estimate of bacterial production. The lowest estimate assumes zero isotope dilution for converting 14C-leucine incorporation rates into bacterial production and a 50% growth efficiency. In the mesopelagic zone, this estimate implies that bacterial account for 52 and 41% of the POC sinking flux as measured by sediment traps in May and August, respectively. The highest estimate, assuming two-fold isotope dilution of 14C-leucine and a 30% growth efficiency, yields bacterial carbon consumption values of 172 and 137% of the POC downward flux in both months. This indicates that bacteria are important, if not the major consumers of organic matter in the mesopelagic zone of the subarctic Pacific. © 1992., Cited By (since 1996):27, Oceanography, ,
Author: Simon, Welschmeyer, Kirchman
Date: 1992-01-01T00:00:00Z

Title: Characterizing estuarine plume discharge into the coastal ocean using fatty acid biomarkers and pigment analysis
Description: The transformation of estuaries by human activities continues to alter the biogeochemical balance of the coastal ocean. The disruption of this balance can negatively impact the provision of goods and services, including fisheries, commerce and transportation, recreation and esthetic enjoyment. Here we examine a link, between the Elkhorn Slough and the coastal ocean in Monterey Bay, California (USA) using a novel application of fatty acid and pigment analysis. Fatty acid analysis of filtered water samples showed biologically distinct water types between the Elkhorn Slough plume and the receiving waters of the coastal ocean. A remarkable feature of the biological content of the plume entering the coastal ocean was the abundance of bacteria-specific fatty acids, which correlated well with concentrations of colored dissolved organic matter (CDOM). Pigment analysis showed that plume waters contained higher concentrations of diatoms and cryptophytes, while the coastal ocean waters showed higher relative concentrations of dinoflagellates. Bacteria and cryptophytes can provide a source of labile, energy-rich organic matter that may be locally important as a source of food for pelagic and benthic communities. Surface and depth surveys of the plume show that the biogeochemical constituents of the slough waters are injected into the coastal waters and become entrained in the northward flowing, nearshore current of Monterey Bay. Transport of these materials to the northern portion of the bay can fuel a bloom incubator, which exists in this region. This study shows that fatty acid markers can reveal the biogeochemical interactions between estuaries and the coastal ocean and highlights how man-made changes have the potential to influence coastal ecological change. © 2014 Elsevier Ltd.
Author: Fischer, Ryan, Levesque, Welschmeyer
Date: 2014-01-01T00:00:00Z

Title: Alternative, indirect measures of ballast water treatment efficacy during a shipboard trial: A case study
Description: Cited By :2, A shipboard study was conducted aboard the cruise ship Coral Princess during a scheduled cruise from San Pedro, CA, USA to Vancouver, British Columbia, Canada. The investigation involved three members of the global TestNet group, with experience in certification testing of ballast water treatment systems (BWTS) designed to eliminate entrained invasive species. A UV-based ballast water treatment system had been employed aboard the vessel for more than 10 years. A variety of established and experimental assessment techniques were employed, both aboard the ship and following shipment of samples via road (5 days) and air (7 days) to remote laboratories. The study was designed to compare the performance of different techniques in assessing BWTS compliance with international regulations, and to test the feasibility of compliance assessment by Port State Control internationally using different laboratories. Overall, biological end-points showed effective treatment of ballast water as judged by the percentage removal (mortality) of organisms in treated samples. Sample transport indicated generally good potential for ‘off-site’ sample analysis and displayed a possible latent effect of treatment as judged by a decline in photosynthetic yield associated with delayed analysis.
Author: Wright, Welschmeyer, Peperzak