Risa A. Cohen

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Nutrient inputs to estuaries are increasing worldwide, and anthropogenic contributions are increasingly complex and difficult to distinguish. Measurement of integrated effects of salinity and nutrient changes simultaneously can help ascertain whether N sources of similar magnitude and stable isotope (sigma15N) signatures are river dominated. We used(More)
A key device in future high speed short reach interconnect technology will be the optical modulator. These devices, in silicon, have experienced dramatic improvements over the last 6 years and the modulation bandwidth has increased from a few tens of MHz to over 30 GHz. However, the demands of optical interconnects are significant. Here we describe an(More)
Synthetic surfactants in cleaners and detergents commonly contaminate freshwater systems, therefore use of low-toxicity alternatives is becoming increasingly important. Alkyl polyglucosides (APGs) derived from natural products are less toxic than synthetic surfactants, and degrade rapidly reducing chemical exposure time. However, single species toxicity(More)
UNLABELLED PREMISE OF THE STUDY A microcosm unit with tidal simulation was developed to address the challenge of maintaining ecologically relevant tidal regimes while performing controlled greenhouse experiments on smooth cordgrass, Spartina alterniflora. • METHODS AND RESULTS We designed a simple, inexpensive, easily replicated microcosm unit with(More)
Growth and survival of transplanted vegetation for salt marsh restoration can be greatly affected by edaphic conditions. We investigated the potential for an organic carbon sediment amendment, alginate, to enhance establishment and growth of Spartina alterniflora transplants, as well as colonization by macroinvertebrates commonly associated with S.(More)
In nitrogen-limited temperate marshes, increasing nitrogen availability via biological mechanisms such as N2 fixation and organic matter mineralization may lead to elevated marsh plant growth and macroinvertebrate densities. A polysaccharide, alginate, known to enhance microbial activity was added to sediment in a salt marsh (GA, USA) and the responses of(More)
Salt marsh restoration is hypothesized to provide shoreline stabilization, increased fish habitat, and organic carbon subsidies for estuarine food webs. Organic carbon comes from diverse primary producers that differ in carbon fixation rates and areal extent within wetland systems. This study was designed to obtain some of the first estimates of the(More)
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