Search

Highlights: [•] Alexandrium tamarense and Alexandrium fundyense from Narragansett Bay, RI, USA are identified via thecal plate morphology and molecular analysis. [•] A suite of toxins (C1/2, B1 (GTX-5), STX, GTX-2/3. Neo, and GTX-1/4) are identified in both A. tamarense (6.31fmolcell−1 STX equivalent) and A. fundyense (9.56fmolcell−1 STX equivalent) isolated from Narragansett Bay. [•] First report of regular appearance of the A. fundyense/A. tamarense species complex in Narragansett Bay. [Copyright &y& Elsevier]

Abstract: The Benthic Habitat Quality (BHQ) index was used to assess habitat visible in sediment profile images (SPI) following hypoxia disturbance in a shallow (<10m) estuarine embayment in Rhode Island, USA. We tested for associations between the BHQ, SPI features and water quality over several assessment windows (1, 3, 7, 14, and 28 days prior to imaging) and at multiple dissolved oxygen (DO) thresholds (2.0mgl−1, 2.9mgl−1, and 4.8mgl−1). Using categorical data analysis, we established empirical relationships between hypoxia prevalence and presence/absence of biogenic features visible in SPI. Fecal pellets, tubes, feeding pits, voids, mounds, and BHQ score were good affirmative features, meaning that their presence (or score greater than 5) indicated a high probability of good water quality. However, low sensitivity to hypoxia precluded their usefulness as indicators, and was attributed to rarity in images and to factors acting on time intervals longer than those examined, e.g. long-term organic enrichment or hypoxia. Burrow structures and the apparent redox potential discontinuity (aRPD), or oxidized layer of surface sediment, were good discriminatory features, with high sensitivity and specificity for both hypoxia and normoxia. Both were strong surrogates for water quality over multiple assessment windows and DO thresholds, and had the highest overall predictive values. We conclude that SPI images can be used to widen the spatial extent of water quality monitoring efforts by utilizing the relationships between aRPD, burrows and hypoxia prevalence. [Copyright &y& Elsevier]

Abstract: Food chain and food web have been, thus far, depicted by number of individuals, matter (biomass) and energy, but not by the concept concerning to the second law of thermodynamics. The present paper takes up three U.S. mid-Atlantic estuaries and delineates marine trophic structure in the term of the concept of this missing link: the second law of thermodynamics. Homeostatic structure and function of living systems is maintained by chemical, physical and organic activities in biotic systems. These activities are supported by chemical energy released by decomposition of macromolecules in organisms by oxygen incorporated from the outside (respiration). This chemical energy finally becomes heat energy and is discarded to the outside. This heat energy is dissipation function in thermodynamics, and dissipation function divided by absolute temperature of organism–water is entropy production. As example, mid-Atlantic estuaries on the eastern U.S. coast are analyzed, based on the study of (Monaco, M.E., Ulanowicz, R.E., 1997. Comparative ecosystem trophic structure of three U.S. mid-Atlantic estuaries. Mar. Ecol. Prog. Ser. 161, 239–254). They give 13–14 trophic compartments in each estuaries, and respiration and other characteristic quantities for each trophic compartments. Trophic position of compartment in each estuary is adopted and arranged in accord to the food web diagrams of (Monaco, M.E., Ulanowicz, R.E., 1997. Comparative ecosystem trophic structure of three U.S. mid-Atlantic estuaries. Mar. Ecol. Prog. Ser. 161, 239–254). Plots of trophic number versus respiration become of half-pyramid shape, which is also applied to dissipation function because respiration is equal to dissipation function in thermodynamics. Annual average temperature at average depth in Narragansett estuary is, for example, 10.0°C (=283.2K). The difference between maximum and minimum temperature at averaged depth is 14.2°C (=287.4K). This difference is small compared with the absolute temperature scale. Hence let us make an approximation that the temperature of the water body of this estuary is about constant and uniform over a year and 10.0°C=283.2K. Entropy production is obtained by dividing dissipation function by this value. Pattern of trophic position versus entropy production multiplied by the temperature is of similar shape to dissipation function: half-pyramid. Other two estuaries show similar results. [Copyright &y& Elsevier]

Polycyclic aromatic hydrocarbons (PAHs) were measured in 41 surface sediments from Narragansett Bay, RI. All the analytes generally decrease down bay from the Seekonk, Providence and Taunton Rivers at the head of the bay. Total PAHs ranged from 0.569 to 216 μg/g with 27% exceeding the effects range median (ERM) of 44.8 μg/g and 73% of the stations exceeding the effects range low (ERL) of 4.02 μg/g ().Based on principal component analysis, the major source of the contaminants in Narragansett Bay was the Providence River while the coves and Taunton River/Mt. Hope Bay appeared to only have a limited influence on the open bay. PAH source ratios indicate that creosote and/or coal may be the most significant contributor of pyrogenic high molecular weight PAHs in Narragansett Bay, along with significant contributions from diesel exhaust. [Copyright &y& Elsevier]

Fish and shellfish abundance for Narragansett Bay and coastal Rhode Island waters from landing data and surveys were compared over the past century using the originally abundant species. The first quantitative data became available in the late 1800s as conflicts developed between the hook-and-line fishermen and the fish trap fishermen with the hook- and-line fishermen claiming a reduction in the availability of fish. Subsequent data were available from the state of Rhode Island and National Marine Fisheries Service landing data, and from the Graduate School of Oceanography and Rhode Island Department of Environmental Management surveys. In the early records, several anadromous fish species were abundant which are no longer abundant or not reported in recent surveys such as alewife, shad, and smelt. Changes in shellfish include the disappearance of soft-shell clam, cultured oyster, and scallop and a replacement by quahog although the landing of quahog is recently down. Lobster was abundant in the early record and has increased in abundance in the recent records. Several species of fish that once dominated the catch have decreased. Boreal species like winter flounder have decreased with increasing water temperatures over the past 30 years. Migratory fish like menhaden and food fish like scup have decreased to low levels in the late 1900s compared to the 1800s. Predictions of fish yield from primary production indicate that migratory populations sustained the fishery in the late 1800s but in the late 1900s these populations no longer exist to sustain such a fishery. Survey data indicate these waters without fish have become prime habitat for crabs and lobsters. The legislatures of Massachusetts and Rhode Island in 1869-1870 requested a law be passed prohibiting fixed apparatus for catching fish. (Spencer F. Baird, 1873). The compelling argument is not regulation and terse fact; rather we? must accept our responsibilities and obligations, as users and temporary... [ABSTRACT FROM AUTHOR]

Public participation in water quality planning for upper Narragansett Bay, Rhode Island (RI), has changed from hearings to a stakeholder approach. As a result of this innovation in process, knowledge about environmental science and about citizen preferences is more widely shared. High levels of stakeholder motivation to contribute, as evidenced by meeting attendance and participation, developed from this new distribution of power and knowledge. Synergisms among process, knowledge, and motivation contributed to a much more acceptable plan for enhancing water quality. In Narragansett Bay the solution adopted to improve water quality was to store and treat combined sewer overflows (CSOs). This stakeholders' plan requires a 2-year period of monitoring after the initial phase of building the system. Subsequent construction will complete the project as originally planned or revise it in an adaptive manner if more effective solutions than were originally envisioned become available. [ABSTRACT FROM AUTHOR]

The brown tide picoalga Aurecoccus anophagefferens Hargraves et Sieburth was present in approximately equal numbers in 12 large sale (13,000 L) mesocosms at the start of a nutrient addition experiment in June 1985. Increases in abundance in untreated systems mimicked the pattern of bloom development in Narragansett Bay, Rhode Island, the seawater source for the experiment in June 1985. Increases in abundance in untreated systems mimicked the pattern of bloom development in Narragansett Bay, Rhode Island, the seawater source for the experiment. Aureococcus increased to maximal values of 2.6 × 10[sup9] cells · L[sup-1] and persisted at high numbers (> 10[sup8] cells·L[SUP-1]) for 7-8 weeks> In nutrient addition tanks, the picoalgae bloomed briefly (1-3 weeks) buts rapidly declined to the usual level (∼10[sup2] cells·L[SUP-1] for eukaryotic alage in Narragansett Bay. The decline in picoalgae in all nutrient treated followed by an increase in total diatoms in all nutrient treated tanks. Mean picoalgae abundance in the mesocosms and the bay was significantly (P < 0.05) and inversely correlated (r = -0.93) with mean concentration of dissolved inorganic nitrogen. The persistence of the brown tide species in control mesocosms nad Narragansett Bay appears related to its ability to grow at very low concentrations of dissolved inorganic nitrogen, Levels previously shown to limits diatom growth [ABSTRACT FROM AUTHOR]