Abstract. We examined the importance of nitrogen inputs from groundwater and runoff in a small coastal marine cove on Cape Cod, MA, USA. We evaluated groundwater inputs by three different methods: a water budget, assuming discharge equals recharge; direct measurements of discharge using bell jars; and a budget of water and salt at the mouth of the Cove over several tidal cycles. The lowest estimates were obtained by using a water budget and the highest estimates were obtained using a budget of water and salt at the Cove mouth. Overall there was more than a five fold difference in the freshwater inputs calculated by using these methods.Nitrogen in groundwater appears to be largely derived from on site septic systems. Average nitrate concentrations were highest in the region where building density was greatest. Nitrate in groundwater appeared to behave conservatively in sandy sediments where groundwater flow rates were high (> 1 l/m 2 /h), indicating that denitrification was not substantially reducing external nitrogen loading to the Cove. Nitrogen inputs from groundwater were approximately 300 mmol-N/m3/y of Cove water. Road runoff contributed an additional 60 mmol/m3/y. Total nitrogen inputs from groundwater and road runoff to this cove were similar in magnitude to river dominated estuaries in urbanized areas in the United States.

Deep basins in the PettaquamscuttRiver ( Rhode Island), a narrow estuary, are highly stratified.Biogenic H&i accumulates in bottom water to a concentration of 4.5 mM, several times the concentration reported in other anoxic marine or estuarine environments. The alkalinity, which reaches a concentration of 12.66 meq/liter, as well as the observed pH, can be cxplaincd by considering the water a solution of several alkaline substances and one acid, H&03.Knull and Richards' model of alkalinity in anoxic water is improved by taking NHs into account. Richards' model of sulfate reduction by organic matter accurately predicts the concentrations of those major products influencing alkalinity and pH.

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The Galápagos Islands have long been the object of worldwide scientific interest. Increased demands on coastal and marine resources there, to serve a growing resident population and to accommodate potentially expanded tourism, signal a need for greater attention to the management of these resources. The paper provides a brief overview of the challenges facing integrated coastal and marine area management in the Galápagos Islands of Ecuador, describes a cooperative project between the government of Ecuador and the Woods Hole Oceanographic Institution to devise concepts for improved management of the archipelago's coastal and marine resources, and reports on the findings of that study. The basic elements of a CZM and MRM system are already in place in the Galápagos, but they are uncoordinated and largely ad hoc in nature. A two-zone management scheme for coastal and marine resources, proposed by Knecht (1984) is outlined. It avoids the establishment of complicated new systems of boundaries and institutions, instead adapting itself to the existing situation. Future directions for the cooperative research by Woods Hole and the government of Ecuador are indicated.