Direct and indirect effects of diesel-contaminated sediment on microalgae, meiofauna, and meiofauna-microalgae trophic interactions were examined in a microcosm study of the sediment community from a Spartina aZterniJora salt marsh. Microcosms of natural sediment were given small daily doses of contaminated sediment over a 28-d period, creating low-, medium-, and high-diesel treatment concentrations of -0.5, 5.5, and 55 ppm PAH, respectively. Diesel caused initial (within 7 h) reductions in microalgal grazing by meiobenthic harpacticoid copepods. Over longer periods of exposure (7-28 d), grazing on microalgae by copepods as a group was reduced in highdiesel treatments, primarily because of high copepod mortality. In contrast, grazing by and abundance of Cletocamptus deitersi (a copepod) was significantly enhanced in high-diesel treatments. Concurrent with reduced grazing by copepods, nematode grazing rates increased significantly in high-diesel treatments, indicating possible competition for microalgae between copepods and nematodes. In spite of transiently enhanced grazing by nematodes and C. deitersi, total meiofaunal grazing on microalgae was reduced in high-diesel treatments. Increased Chl a: pheopigment ratios in contaminated sediments were also indicative of reduced grazing pressure. A large (10X) increase in microalgal biomass was observed in high-diesel treatments and was likely a consequence of reduced meiofaunal grazing. The general responses observed in microcosms were also observed in a field study of polycyclic aromatic hydrocarbon contamination. Collectively, our data indicate that benthic microalgal biomass is controlled by meiofaunal grazing and that meiofauna may compete for limited algal resources. Furthermore, consideration of multiple trophic levels and their interactions allows a more complete and ecologically meaningful understanding of the mechanisms by which contaminants induce changes in natural communities.

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The Biology Intensive Orientation for Students (BIOS) Program at Louisiana State University was designed to increase the success of incoming freshman biology majors in the first course in their major. The program combined content lectures and examinations for BIOL 1201-Introductory Biology for Science Majors, the first course in their major, as well as learning styles assessments and informational sessions intended to provide the students with a preview of the requirements of biology, and the pace of college. BIOS participants showed increased success and retention in the biology major, and remained on track to graduate in 4 years at a significantly higher rate than students who did not participate in BIOS.

The authors report on four annual professional development STAR (Scientific Teaching, Assessment, and Resources) workshops offered to faculty from community colleges, 2-yr campuses, and public and private research universities. A survey of participants indicates that, in the opinion of faculty from both the 2- and 4-yr campuses, STAR had a positive impact on teaching, student learning, and engagement.