Stuart E. G. Findlay

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Heterotrophic bacteria are thought to be important components of aquatic ecosystems in several ways. These bacteria remineralize organic materials and convert some organic material into bacterial biomass. We examined data from 70 studies in which estimates of production of heterotrophic bacterial biomass (bacterial production) were reported for freshand(More)
The hyporheic zone is an active ecotone between the surface stream and groundwater. Exchanges of water, nutrients, and organic matter occur in response to variations in discharge and bed topography and porosity. Upwelling subsurface water supplies stream organisms with nutrients while downwelling stream water provides dissolved oxygen and organic matter to(More)
This paper compares the available North Americanliterature and data concerning several ecologicalfactors affecting Phragmites australisin inlandfreshwater, tidal fresh, and tidal brackish marshsystems. We compare aboveground productivity, plantspecies diversity, and sediment biogeochemistry; andwe summarize Phragmiteseffects on faunalpopulations in these(More)
19 B ivalves (clams and mussels) are among the most familiar of aquatic organisms. Many have been used by humans for centuries as important sources of food and ornament, and some species are economically important pests, fouling water intakes and other structures. It is only recently, however, that ecologists have begun to understand that bivalves also play(More)
Changes in the biomass of benthic bivalves can cause dramatic changes in total grazing pressure in aquatic systems, but few studies document ecosystem-level impacts of these changes. This study documents a massive decline in phytoplankton biomass concurrent with the invasion of an exotic benthic bivalve, the zebra mussel (Dreissena polymorpha), and(More)
Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from(More)
Sodium and chloride concentrations and export increased from 1986 to 2005 in a rural stream in southeastern New York. Concentrations increased 1.5 mg/L per year (chloride) and 0.9 mg/L per year (sodium), and export increased 33,000 kg/year (chloride) and 20,000 kg/year (sodium) during this period. We estimate that salt used for deicing accounted for 91% of(More)
In the northeast US removal of exotic and invasive plant species is a common wetland restoration activity and the invasive common reed (Phragmites australis) is often the target of control efforts. We examined effects of reed removal on sediment nutrient pools and denitrification potential in a tidal freshwater marsh on the Connecticut River. In the first(More)
Bacterial production is the entry point for detrital macronutrients into aquatic food webs. Many factors affect productivity, but the heterogeneity of detrital substrates and the diversity of microbial communities confound simple relationships between carbon supply and growth. WC tried to link the two by analyzing extracellular enzyme activities. Water(More)
This study examines the effect of four tree species on nitrogen (N) retention within forested catchments of the Catskill Mountains, New York (NY). We conducted a 300-day 15N field tracer experiment to determine how N moves through soil, microbial, and plant pools under different tree species and fertilization regimes. Samples were collected from(More)