1. NEILSON A.H. & LEWIN R.A. 1974. The uptake and uti­ lization of organic carbon by algae: an essay in compar­ ative biochemistry (including the addenda by N.J. Antia). Phycologia 13: 227-264. 2. PROCfOR V.W. 1975. The nature of charophyte species. Phycologia 14: 97-113. 3. HOEK C. VAN DEN 1975. Phytogeographic provinces along the coasts of the northern Atlantic Ocean. Phycologia 14: 317-330. 4. JO HANSEN H. W. 1976. Current status of generic concepts in coralline algae (Rhodophyta). Phycologia 15: 221-244. 5. W YNNE M.J. & LoISEAUX S. 1976. Recent advances in life history studies of the Phaeophyta. Phycologia 15: 435452. 6. STARKS T.L., SHUBERT L.E. & T RAINOR F.R. 1981. Ecol­ ogy of soil algae: a review. Phycologia 20: 65-80. 7. MOESTRUP 0. 1982. Flagellar structure in algae. A review with observations particularly on the Chrysophyceae, Phaeophyceae (Fucophyceae), Euglenophyceae and Reck­ ertia. Phycologia 21: 427-528. 8. WOELKERLING WM J. 1983. The Audouinella (Acrochae­ tium-Rhodochorton) complex (Rhodophyta): present per­ spectives. Phycologia 22: 59-92. 9. STEIN J.R. & BORDEN c.A. 1984. Causative and beneficial algae in human disease conditions: a review. Phycologia 23: 485-50 1. 10. HOSHAW R. W. & MCCOURT R.M. 1988. The Zygnema­ taceae (Chlorophyta): a twenty-year update of research. Phycologia 27: 511-548. II. ANTIA N.J., H ARRI SON P.J. & OLIVEIRA L. 1991. The role of dissolved organic nitrogen in phytoplankton nutrition, cell biology and ecology. Phycologia 30: 1-89. 12. KAPRAUN D.F. 1993. Karyology of marine green algae. Phycologia 32: 1-21.

A review of harmful algal blooms and their apparent global increase

(2002). The Effects of Harmful Algal Blooms on Aquatic Organisms. Reviews in Fisheries Science: Vol. 10, No. 2, pp. 113-390.

The Effects of Harmful Algal Blooms on Aquatic Organisms

The Mississippi River system ranks among the world's top 10 rivers in freshwater and sediment inputs to the coastal ocean. The river contributes 90% of the freshwater loading to the Gulf of Mexico, and terminates amidst one of the United States' most productive fisheries regions and the location of the largest zone of hypoxia, in the western Atlantic Ocean. Significant increases in riverine nutrient concentrations and loadings of nitrate and phosphorus and decreases in silicate have occurred this century, and have accelerated since 1950. Consequently, major alterations have occurred in the probable nutrient limitation and overall stoichiometric nutrient balance in the adjacent continental shelf system. Changes in the nutrient balances and reduction in riverine silica loading to, the continental shelf appear to have led to phytoplankton species shifts offshore and to an increase in primary production. The phytoplankton community response, as indicated by long-term changes in biological uptake of silicate and accumulation of biologically bound silica in sediments, has shown how the system has responded to changes in riverine nutrient loadings. Indeed, the accumulation of biologically bound silica in sediments beneath the Mississippi River plume increased during the past two decades, presumably in response to, increased nitrogen loading. The duration, size, and severity of hypoxia has probably increased as a consequence of the increased primary production. Management alternatives directed at water pollution issues within the Mississippi River watershed may have unintended and contrasting impacts on the coastal waters of the northern Gulf of Mexico.

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Nutrient changes in the Mississippi River and system responses on the adjacent continental shelf

Phytoplankton blooms are prominent features of biological variability in shallow coastal ecosystems such as estuaries, lagoons, bays, and tidal rivers. Long-term observation and research in San Francisco Bay illustrates some patterns of phytoplankton spatial and temporal variability and the underlying mechanisms of this variability. Blooms are events of rapid production and accumulation of phytoplankton biomass that are usually responses to changing physical forcings originating in the coastal ocean (e.g., tides), the atmosphere (wind), or on the land surface (precipitation and river runoff). These physical forcings have different timescales of variability, so algal blooms can be short-term episodic events, recurrent seasonal phenomena, or rare events associated with exceptional climatic or hydrologic conditions. The biogeochemical role of phytoplankton primary production is to transform and incorporate reactive inorganic elements into organic forms, and these transformations are rapid and lead to measurable geochemical change during blooms. Examples include the depletion of inorganic nutrients (N, P, Si), supersaturation of oxygen and removal of carbon dioxide, shifts in the isotopic composition of reactive elements (C, N), production of climatically active trace gases (methyl bromide, dimethylsulfide), changes in the chemical form and toxicity of trace metals (As, Cd, Ni, Zn), changes in the biochemical composition and reactivity of the suspended particulate matter, and synthesis of organic matter required for the reproduction and growth of heterotrophs, including bacteria, zooplankton, and benthic consumer animals. Some classes of phytoplankton play special roles in the cycling of elements or synthesis of specific organic molecules, but we have only rudimentary understanding of the forces that select for and promote blooms of these species. Mounting evidence suggests that the natural cycles of bloom variability are being altered on a global scale by human activities including the input of toxic contaminants and nutrients, manipulation of river flows, and translocation of species. This hypothesis will be a key component of our effort to understand global change at the land-sea interface. Pursuit of this hypothesis will require creative approaches for distinguishing natural and anthropogenic sources of phytoplankton population variability, as well as recognition that the modes of human disturbance of coastal bloom cycles operate interactively and cannot be studied as isolated processes.

Phytoplankton bloom dynamics in coastal ecosystems: A review with some general lessons from sustained investigation of San Francisco Bay, California

1. Freshwater systems are losing biodiversity at a rapid rate, yet we know little about the functional role of most of this biodiversity. The ecosystem roles of freshwater burrowing bivalves have been particularly understudied. Here we summarize what is known about the functional role of burrowing bivalves in the orders Unionoida and Veneroida in lakes and streams globally.

2. Bivalves filter phytoplankton, bacteria and particulate organic matter from the water column. Corbicula and sphaeriids also remove organic matter from the sediment by deposit feeding, as may some unionids. Filtration rate varies with bivalve species and size, temperature, particle size and concentration, and flow regime.

3. Bivalves affect nutrient dynamics in freshwater systems, through excretion as well as biodeposition of faeces and pseudofaeces. Excretion rates are both size and species dependent, are influenced by reproductive stage, and vary greatly with temperature and food availability.

4. Bioturbation of sediments through bivalve movements increases sediment water and oxygen content and releases nutrients from the sediment to the water column. The physical presence of bivalve shells creates habitat for epiphytic and epizoic organisms, and stabilizes sediment and provides refugia for benthic fauna. Biodeposition of faeces and pseudofaeces can alter the composition of benthic communities.

5. There is conflicting evidence concerning the role of resource limitation in structuring bivalve communities. Control by bivalves of primary production is most likely when their biomass is large relative to the water volume and where hydrologic residence time is long. Future studies should consider exactly what bivalves feed upon, whether feeding varies seasonally and with habitat, and whether significant overlap in diet occurs. In particular, we need a clearer picture of the importance of suspension versus deposit feeding and the potential advantages and tradeoffs between these two feeding modes.

6. In North America, native burrowing bivalves (Unionidae) are declining at a catastrophic rate. This significant loss of benthic biomass, coupled with the invasion of an exotic burrowing bivalve (Corbicula), may result in large alterations of ecosystem processes and functions.

The functional role of burrowing bivalves in freshwater ecosystems

This 1997 book is about those animals found on the sea floor that live by filtering microscopic particles carried to them by water currents. Its purpose is to review what is known about the biology of suspension feeders in relation to their flow environment. The book includes the larval biology, physiology, ethology and ecology of suspension feeders interacting with water flow. It will be of value to marine scientists beginning research in the interdisciplinary field of hydrodynamics and benthic biology, and it is the first attempt to provide a comprehensive overview of this synthesis from the biological viewpoint.

Benthic suspension feeders and flow

Circumstantial evidence is presented that domoic acid detected in softshell clams Mya arenana and blue mussels Mytilus edulis from the southwestern Bay of Fundy, eastern Canada, during July to October 1988 was obtained by feedlng on the pennate diatom Nitzschia pseudodelicatissima. T h ~ s microalga was the most abundant organism observed in weekly samples collected at the surface, 10 m depth and bottom from nearly all of the 18 locations sampled during the same penod. Phytoplankton net hauls consisting principally of N, pseudodelicatissima contained levels of domoic acid up to 3.5 pg g-l Isolates of 9 dominant phytoplankton species occurring in the southwestern Bay of Fundy during July to October 1988 were cultured and tested for the presence of domoic acid; only N. pseudodelicatissima cultures produced the toxin at concentrations of 7.0 X 1 0 l ~ to 9.8 X 10-l4 g cell-' Since cultures of N. pseudodelicatissima were not axenic, the possibility exists that either an intra or extracellular microorganism is acting independently, or in association with the diatom, to produce domoic acid.

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Nitzschia pseudodelicatissima : a source of domoic acid in the Bay of Fundy, eastern Canada

The effects of velocity and seston concentration on the exhalant siphon area, valve gape and filtration rate of the mussel Mytilus edulis

We examined whether populations of the blue mussel Mytilus edulis (Linnaeus, 1758) and horse mussel Modiolus modiolus (Linnaeus, 1758) could, by their feeding activities, deplete the sestonic food ...

David Wildish

Papers

Benthic suspension feeders and flow

Nitzschia pseudodelicatissima : a source of domoic acid in the Bay of Fundy, eastern Canada

The effects of velocity and seston concentration on the exhalant siphon area, valve gape and filtration rate of the mussel Mytilus edulis

Importance to Mussels of the Benthic Boundary Layer

Giant scallop feeding and growth responses to flow