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We explore how anomalously strong winter storms, superposed with managed nitrogen reduction, impacted the 2010 and 2018 spring blooms in the Narragansett Bay (41.62° N, 71.35° W). Anomalously strong winter storms preceding spring of 2010 and 2018 increased annual nutrient inputs above the long-term average annual values for the year, causing a large phytoplankton bloom in spring 2010 and a massive winter-spring bloom in 2018. Flooding from the stronger storm in 2010 caused a smaller increase in primary productivity than the smaller storms prior to spring 2018, probably due to increased flushing rates during the 2010 storm. Neither storm enhanced hypoxia the following summer. During both summers, hypoxia was typical of minimal-hypoxia years, indicating that managed nitrogen reduction which is strongest during summer, remained adequate even in the aftermath of organic inputs from large storms during the colder months. Additionally, some commercially fished species appeared to increase after the storm events. Storm nutrient impacts on commercial species suggest that increasing nitrogen inputs from treatment facilities in colder months might enhance Bay fisheries for squid and hard clam without diminishing summer water quality. [ABSTRACT FROM AUTHOR]

This paper documents the changes that followed large nutrient (N and P) and organic matter input reductions to a major metropolitan marine bay, Boston Harbor (USA). Before input reduction, its N and P inputs fell in the upper range of the < 1–> 300 gN m−2 year−1 and < 0.1–> 40 gP m−2 year−1 for coastal systems. Elevated nutrient and organic matter inputs are recognized causes of coastal eutrophication. Treatment upgrades and then diversion of its wastewater discharges offshore, lowered its N, P, and organic C inputs by 80–90%. The input decreases lowered its trophic status from hypereutrophic to eutrophic–mesotrophic. With the reversal of hypereutrophication, pelagic production and phytoplankton biomass decreased, and the nitrogen limitation relative to phosphorus limitation increased. Benthic metabolism and dissolved inorganic N fluxes decreased, and benthic–pelagic coupling was altered. Bottom-water dissolved oxygen, already at healthy levels, increased, and seagrass expanded. Coastal management requires that the changes, following the nutrient and organic matter input reductions implemented to address eutrophication, be understood. Boston Harbor's recovery, because its water column was vertically well mixed and marine, was more pronounced than in many other systems. [ABSTRACT FROM AUTHOR]

Except for the Providence River and side embayments like Greenwich Bay, Narragansett Bay can no longer be considered eutrophic. In summer 2012 managed nitrogen treatment in Narragansett Bay achieved a goal of reducing effluent dissolved inorganic nitrogen inputs by over 50%. Narragansett Bay represents a small northeast US estuary that had been heavily loaded with sewage effluent nutrients since the late 1800s. The input reduction was reflected in standing stock nutrients resulting in a statistically significant 60% reduction in concentration. In the Providence River estuary, total nitrogen decreased from 100 μm to about 40 μm, for example. We tested four environmental changes that might be associated with the nitrogen reduction. System apparent production was significantly decreased by 31% and 45% in the upper and mid Bay. Nutrient reductions resulted in statistically improved water clarity in the mid and upper Bay and in a 34% reduction in summer hypoxia. Nitrogen reduction also reduced the winter spring diatom bloom; winter chlorophyll levels after nutrient reduction have been significantly lower than before the reduction. The impact on the Bay will continue to evolve over the next few years and be a natural experiment for other temperate estuaries that will be experiencing nitrogen reduction. To provide perspective we review factors effecting hypoxia in other estuaries with managed nutrient reduction and conclude that, as in Narragansett Bay, physical factors can be as important as nutrients. On a positive note managed nutrient reduction has mitigated further deterioration in most estuaries. [ABSTRACT FROM AUTHOR]

Primary production was measured from 1992–2010 in Massachusetts Bay and just outside Boston Harbor for the Massachusetts Water Resources Authority's outfall monitoring program. In 2003, annual primary production decreased by 221–278 g C m−2 year−1, with decreased rates continuing through 2010. Based on a conceptual model, oceanographic and meteorological variables were analysed with production rates to determine if concurrent environmental changes were responsible for the reduced primary production in Massachusetts Bay. Results indicated that a stronger influx of low salinity water from the Western Maine Coastal Current (WMCC) in recent years might be responsible for the decreases. The WMCC appeared to have become fresher due to increased river discharge in the western Gulf of Maine. Northeasterly winds in recent years promoted the WMCC intrusion into Massachusetts Bay. Correlation between primary production and surface salinities suggested an impact of the WMCC on production rates. We hypothesized that increased stratification resulted in reduced vertical mixing and reduced nutrient concentrations in surface waters for phytoplankton growth. However, no significant correlations were observed between the annual primary production and nutrient concentrations in Massachusetts Bay. Reduced production rates in Massachusetts Bay have, however, been associated with reduced zooplankton abundances, benthic ammonium fluxes and sediment oxygen demand in summer months. [ABSTRACT FROM PUBLISHER]

Auker, L. A., and Oviatt, C. A. 2008. Factors influencing the recruitment and abundance of Didemnum in Narragansett Bay, Rhode Island. – ICES Journal of Marine Science, 65: 765–769.The non-indigenous colonial tunicate Didemnum sp. A has been observed in Narragansett Bay, Rhode Island, since 2000. We compared weekly recruitment of the species and environmental parameters (i.e. temperature, salinity, chlorophyll a, dissolved oxygen, pH, and nutrient concentrations) over a 6-month period among three sites: (i) the University of Rhode Island Graduate School of Oceanography dock (GSO), (ii) the Department of Environmental Management pier at Fort Wetherill (FW), and (iii) the Prudence Island T-wharf. At the GSO and FW, divers surveyed the sites for percentage cover of Didemnum. To assess the spread of Didemnum in the bay and what factors may predict the tunicate’s presence, we also surveyed intertidal sites in October and November 2005, noting Didemnum presence, salinity, number of boats and moorings, and distances to major ports at each site. GSO had the highest percentage cover of adults and the highest recruitment of the tunicate (p < 0.01), reaching average peak values of 319 individuals per 100 cm2 in September 2005. Temperature and salinity demonstrated the best correlation with recruitment, and higher boat and mooring numbers may be a reliable predictor of tunicate presence. Further monitoring is needed to assess the potential spread of Didemnum throughout Narragansett Bay. [ABSTRACT FROM PUBLISHER]

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]

Carbon (C) cycling is an important attribute of mangrove forests that relates to the structure, function, and resilience of mangroves under environmental change. Increased nutrient enrichment in tropical coastal waters may influence C cycling through organic C mineralization. For example, by alleviating nutrient limitation of the heterotrophic microbial community, nutrient enrichment may enhance C mineralization and facilitate a loss of within-stand C sequestration. Here, we enriched a coastal fringe Rhizophora mangle (L.) mangrove system for two years with two fertilizer regimes to mimic agriculture runoff ("+high" N:P ratio of 50:1) and urban runoff ("+moderate" N:P ratio of 16:1) scenarios as follows: (1) annual loading rate of 70 g N m −2 year −1 and 3.1 g P m −2 year −1 or (2) annual loading rate of 70 g N m −2 year −1 and 9.7 g P m −2 year −1. C mineralization was measured as microbial respiration rates from the forest floor and litter decomposition rates. While decomposing leaf litter and green leaves had lower molar C:N under the +moderate N:P fertilization course, neither fertilization scenario produced an effect on C mineralization processes compared with ambient conditions. Substrate CO 2 flux rates were not different among treatments and ranged from 1.15 to 1.81 μmol CO 2 m −2 s −1 (3.0–4.8 g CO 2 m −2 day −1) following 72 weeks of fertilization and 0.58–1.55 μmol CO 2 m −2 s −1 (1.5–4.1 g CO 2 m −2 day −1) 30 weeks following the end of the experiment. Time to 50% decay of above-ground leaf litter ranged from 61 to 110 days (average 79 days). Below-ground leaf litter material was fully decomposed by 22 months after burial. A15 N pulse-recovery suggests that the majority of the retained fertilizer (22.2 ± 4.4% at 10 months following spike) was taken up by fine roots, though this did not significantly affect CO 2 flux from the forest floor. This work demonstrates that nutrient enrichment by aqueous delivery does not strongly affect organic carbon mineralization in a coastal fringe mangrove within two years. Environmental conditions, substrate quality, and location may play a more substantial role in mangrove C dynamics compared with short-term aqueous-based nutrient enrichment. • Chronic nutrient (N and P) loading to a mangrove wetland applied for two years. • Nutrient enrichment did not change CO 2 flux from the forest floor. • Below-ground organic material decomposed within two years in a fringe mangrove. • Decomposition in mangroves is not strongly enhanced by N enrichment over two years. [ABSTRACT FROM AUTHOR]

A correction to the article "The Western Maine Coastal Current Reduces Primary Production Rates, Zooplankton Abundance and Benthic Nutrient Fluxes in Massachusetts Bay," which appeared in a previous 2014 issue is presented.

We examined the effect of hydrography on benthic-pelagic coupling in a transitional inner continental shelf area. From Oct 2009 to Jul 2012, we measured sediment oxygen demand (SOD), benthic inorganic nutrient fluxes, and sediment characteristics (e.g. chl a and phaeopigment content, grain size, etc.) in two regions of the Southern New England continental shelf: a relatively well mixed ecosystem (Block Island Sound, BIS), and an adjacent, seasonally stratified ecosystem (Rhode Island Sound, RIS). Despite a higher rate of euphotic zone primary production in BIS, benthic metabolism (measured as SOD) was not significantly different between the two areas (BIS = 953.8 ± 88.2 μmol m −2 h −1 ; RIS = 912.2 ± 69.1 μmol m −2 h −1 ). We speculate that the similarity of SOD at these two sites was due to differences in water column hydrography between the Sounds, where the energetic water column mixing in BIS could potentially resuspend organic matter back to the water column to be decomposed before reaching the benthos. Additionally, we think that the seasonal presence of a strong pycnocline in RIS prevented mixing of regenerated DIN and DIP to surface waters for use by phytoplankton. Apparent differences in benthic macrofaunal abundance between Block Island Sound and Rhode Island Sound translated to differences in dissolved inorganic nutrient fluxes between the two areas. Excretion and irrigation activities by the dense amphipod communities in BIS likely caused higher effluxes of DIN ( NH 4 + = 36.9 ± 7.7 μmol m −2 h −1 ; NO X = 23.5 ± 3.4 μmol m −2 h −1 ) and DIP (7.2 ± 1.4 μmol m −2 h −1 ) compared to fluxes in RIS ( NH 4 + = 22.8 ± 4.5 μmol m −2 h −1 ; NO X = 11.1 ± 5.5 μmol m −2 h −1 ; DIP = 3.2 ± 0.8 μmol m −2 h −1 ). These findings indicate that the hydrographic regime of the water column may exert a strong influence on benthic-pelagic coupling dynamics on the Southern New England shelf and in other inner continental shelf ecosystems. [ABSTRACT FROM AUTHOR]

A photosynthetic quotient (PQ) for Narragansett Bay, RI, USA was calculated using concurrent 14C and oxygen light–dark bottle primary production estimations. The current PQ (1.42 ± 0.09) was elevated over the PQ (1.24) calculated in a 1980's mesocosm experiment, stimulating a sensitivity analysis of physiological drivers of the PQ. We speculate that the factor that altered the PQ between surveys was wastewater treatment facility upgrades increasing NO3− effluent proportion from 10 to 40%. [ABSTRACT FROM AUTHOR]

The objective of this paper is to examine the impacts of global climate change on Rhode Island's coastal ecosystems. Average annual air temperature in Rhode Island has increased by 1.7 °C since 1880, water temperatures of Narragansett Bay have increased by 1.2 °C since 1950, precipitation increased 27% between 1895 and 1999, and sea level rose 0.13 m between 1931 and 2007. We can already see the effects of these climatic changes on the Narragansett Bay ecosystem, including ecological changes in the Bay's food web from phytoplankton and zooplankton to fish, e.g., changes in phenology of seasonal phytoplankton blooms and dominant fish species (e.g., Pseudopleuronectes americanus [Winter Flounder]). These climatic changes have increased freshwater inputs and the concomitant pollutant loads into the Bay. Rising sea level has contributed to ongoing erosion of the coast and has put waterfront homes at increased risk. It is imperative to continue monitoring these effects. [ABSTRACT FROM AUTHOR]

Abstract: A variant of the Vertically Generalized Production Model (VGPM) was used to expand the spatial and temporal resolution of production estimates and better characterize the phytoplankton variability in Massachusetts and Cape Cod Bays. Satellite modeled production was used to supplement in situ 14C primary production measurements, which were spatially limited to two shipboard stations in the northern portion of Massachusetts Bay that were sampled up to 17 times per year. Modifications to the model included a regional parameterization of the euphotic depth (Zeu ) and an analysis of the maximum chlorophyll specific carbon fixation rate (), which failed to reveal a correlation between and temperature as suggested by previous studies. This primary production model successfully captured the seasonal and interannual variations of in situ production that were measured using the 14C uptake method and significantly enhanced the spatial and temporal resolution of primary production measurements in Massachusetts Bay. The use of satellite data better characterized event, seasonal and interannual variability of ecosystem primary production and revealed a three-fold decrease in production from the nearshore to offshore regions. Daily production ranged from less than 0.25gCm−2 d−1 in the offshore regions in January to greater than 2gCm−2 d−1 at various times throughout the year in Cape Cod Bay and along the coastline during the summer months. The mean annual production of Massachusetts Bay for the 8-year study period was 220gCm−2. The lowest production was estimated in 2004 (174gCm−2) and the greatest in 2000 (300gCm−2). Comparatively, mean production in Cape Cod Bay was 289gCm−2 and ranged from 231 in 1998 to 358gCm−2 in 2000. Unlike a number of other temperate continental shelf areas where the maximum production occurs during the summer months corresponding to the greatest PAR and temperature, the highest production and largest fraction of the annual production in Massachusetts Bay accompanied the high phytoplankton biomass during the spring (April–May) and fall blooms (September–October). [Copyright &y& Elsevier]

Abstract: Massachusetts Bay, a semi-enclosed embayment (50×100km) in the Northwest Atlantic, is the focus of a monitoring program designed to measure the effects of relocating the Boston Harbor sewage outfall to a site 15km offshore in Massachusetts Bay. The Massachusetts Water Resources Authority (MWRA) in situ monitoring program samples selected stations up to 17 times per year to observe seasonal changes in phytoplankton biomass and other water quality variables. We investigated the feasibility of augmenting the monitoring data with satellite ocean color data to increase the spatial and temporal resolution of quantitative phytoplankton measurements. In coastal regions such as Massachusetts Bay, ocean color remote sensing can be complicated by in-water constituents whose concentrations vary independently of phytoplankton and by inaccurate modeling of absorbing aerosols that tend to be concentrated near the coast. An evaluation of in situ and sea-viewing wide field-of-view sensor (SeaWiFS) measurements from 1998 to 2005 demonstrated that SeaWiFS overestimated chlorophyll a mainly due to atmospheric correction errors that were amplified by absorption from elevated concentrations of chlorophyll a and colored dissolved organic matter. Negative water-leaving radiances in the 412nm band, an obvious artifact of inadequate atmospheric correction, were recorded in approximately 60–80% of the cloud-free images along the coast, while the remaining portions of the Bay only experience negative radiances 35–55% of the time with a clear nearshore to offshore decrease in frequency. Seasonally, the greatest occurrences of negative 412nm radiances were in November and December and the lowest were recorded during the summer months. Concentrations of suspended solids in Massachusetts Bay were low compared with other coastal regions and did not have a significant impact on SeaWiFS chlorophyll a measurements. A regional empirical algorithm was developed to correct the SeaWiFS data to agree with in situ observations. Monthly SeaWiFS composites illustrated the spatial extent of a bimodal seasonal pattern, including prominent spring and fall phytoplankton blooms; and the approximate 115 cloud-free scenes per year revealed interannual variations in the timing, magnitude and duration of phytoplankton blooms. Despite known artifacts of SeaWiFS in coastal regions, this study provided a viable chlorophyll a product in Massachusetts Bay that significantly increased the spatial and temporal synoptic coverage of phytoplankton biomass, which can be used to gain a comprehensive ecosystem-wide understanding of phytoplankton dynamics at event, seasonal and interannual timescales. [Copyright &y& Elsevier]

Abstract: Previous work had indicated that the Virginian Province Index did not perform well in a smaller estuarine complex. While it was hoped that the existing Chesapeake Bay Benthic Index of Biotic Integrity, with its greater number of metrics and habitat separation would be more adaptable, this index also did not perform well outside of Chesapeake Bay. In this study we assembled additional metrics and applied different methods of index compilation to explore the indices relative strengths and weaknesses. Three different approaches were utilized – two multimetric indices (Chesapeake Bay IBI and the Mebane IBI) and a statistical logistic regression technique. The data were subdivided by habitat (salinity and grain size), and indices compiled using the same initial group of benthic metrics. Each approach was examined for its classification accuracy for both reference and impaired sites for the entire Virginian Province. The Chesapeake Bay IBI approach did not perform well in this study. In contrast, another multimetric approach, the Mebane IBI approach, performed well, as did the statistical logistic regression approach. Both techniques have promise for index development and could be useful in applying a biological condition gradient to estuaries. [Copyright &y& Elsevier]

Lagoons are highly productive coastal features that provide a range of natural services that society values. Their setting within the coastal landscape leaves them especially vulnerable to profound physical, ecological, and associated societal disturbance from global climate change. Expected shifts in physical and ecological characteristics range from changes in flushing regime, freshwater inputs, and water chemistry to complete inundation and loss and the concomitant loss of natural and human communities. Therefore, managing coastal lagoons in the context of global climate change is critical. Although management approaches will vary depending on local conditions and cultural norms, all management scenarios will need to be nimble and to make full use of the spectrum of values through which society views these unique ecosystems. We propose that this spectrum includes pragmatic, scholarly, aesthetic, and tacit categories of value. Pragmatic values such as fishery or tourism revenue are most easily quantified and are therefore more likely to be considered in management strategies. In contrast, tacit values such as a sense of place are more difficult to quantify and therefore more likely to be left out of explicit management justifications. However, tacit values are the most influential to stakeholder involvement because they both derive from and shape individual experiences and beliefs. Tacit values underpin all categories of social values that we describe and can be expected to have a strong influence over human behavior. The articulation and inclusion of the full spectrum of values, especially tacit values, will facilitate and support nimble adaptive management of coastal lagoon ecosystems in the context of global climate change. [ABSTRACT FROM AUTHOR]