Michael S. Owens

Learn More
Suspension-feeding eastern oysters, Crassostrea virginica, were once abundant in Chesapeake Bay and may then have exerted top-down control on phytoplankton and also reduced turbidities, thereby increasing light available to benthic plants. Alternatively, oysters may have simply recycled inorganic nutrients rapidly back to the water column, with no(More)
Multi-year nitrogen (N) and phosphorus (P) budgets were developed for the Patuxent River estuary, a seasonally stratified and moderately eutrophic tributary of Chesapeake Bay. Major inputs (point, diffuse, septic, and direct atmospheric) were measured for 13 years during which, large reductions in P and then lesser reductions in N-loading occurred due to(More)
Global loss of 85% of oyster reef ecosystems over the past 130 yr (Beck et al. 2011) has led to both growing recognition of the services once provided by healthy oyster reef ecosystems (Grabowski et al. 2012) and increasing interest in restoring these ecosystems. In Chesapeake Bay, USA, populations of the native oyster Crassostrea virginica have been(More)
Bacillus thuringiensis (ATCC 10792) produces a molybdenum reactive compound (given the trivial name chelin) during growth on iron-deficient medium. This compound accumulates in the culture medium in direct relation to the amount of L-arginine added and reaches a maximum concentration 24 to 48 h after the stationary phase of growth. Chelin absorbs light in(More)
We used metatranscriptomics to study the gene transcription patterns of microbial plankton (0.2 to 64 μm) at a mesohaline station in the Chesapeake Bay under transitions from oxic to anoxic waters in spring and from anoxic to oxic waters in autumn. Samples were collected from surface (i.e., above pycnocline) waters (3 m) and from waters beneath the(More)
Intense annual spring phytoplankton blooms and thermohaline stratification lead to anoxia in Chesapeake Bay bottom waters. Once oxygen becomes depleted in the system, microbial communities use energetically favourable alternative electron acceptors for respiration. The extent to which changes in respiration are reflected in community gene expression have(More)