The influence of mesoscale ocean eddies on near-surface ocean temperature, surface stress and phytoplankton communities is investigated by collocating numerous satellite measurements along with vertical profiles of oceanic temperature and salinity to the interiors of eddies identified and tracked in altimetric sea surface height maps.
The surface currents associated with...
Plant-parasitic nematodes cause more than US $100 billion in annual agriculture loss worldwide. Thorough knowledge of their genetic diversity, and interactions with endosymbionts and environment have the potential to provide valuable insights into the basic biology of these animals, and assist future efforts aimed at management of these plant parasites....
Algal chlorophyll and carotenoid distributions were measured periodically in the euphotic zone of Sta. ALOHA (22º45′N, 158º00′W) between February 1989 and October 1991 to document the variability in phytoplankton abundance and composition. The annual mean depth-integrated (O-200 db) concentration of Chl a displayed significant interannual variability. Seasonal patterns in Chl...
Previous observations of light levels and phytoplankton abundances along the Oregon coast demonstrated that phytoplankton attenuated light sufficiently to potentially limit the growth of intertidal macrophytes and therefore structure local intertidal communities. Inspired by this observation, in spring 2004, I initiated a study to quantify the direct and indirect benthic...
Experiments were designed to answer key questions about diatom-derived organic matter cycling (i.e., production and degradation) in coastal systems. Dissolved organic matter (DOM) production was examined in axenic batch cultures of five diatom species. Dissolved organic carbon (DOC) release rates varied between species, but were significantly higher for all species...
Marine bacteria play vital roles in every niche of the ocean, from small-scale symbioses to large-scale productivity and the regulation of Earth’s climate. Recent advances in molecular tools now allow us to probe the genetic potential of entire microbial communities. The next step is linking these diverse communities to the...
Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect...