Richard A. Hallett

Learn More
Quasi-elastic light scattering and cinematographical techniques were used to investigate the motility of Chlamydomonas reinhardtii (wild type). It was found that quantitative information on the trajectory of motion was required for a meaningful interpretation of the autocorrelation functions. Two models for describing the oscillatory motion of the cell were(More)
Sugar maple, Acer saccharum, decline disease is incited by multiple disturbance factors when imbalanced calcium (Ca), magnesium (Mg), and manganese (Mn) act as predisposing stressors. Our objective in this study was to determine whether factors affecting sugar maple health also affect growth as estimated by basal area increment (BAI). We used 76 northern(More)
The emerald ash borer (EAB) is an exotic insect pest currently threatening ash species in the Great Lakes region. Because of the potential impact on forests in this area, multiple government agencies are currently focusing their efforts on developing new technologies to detect, monitor and control this insect pest. Previous work has shown that hyperspectral(More)
Atmospheric nitrogen (N) deposition is altering biogeochemical cycling in forests and interconnected lakes of the northeastern US, and may shift nutrient limitation from N toward other essential elements, such as phosphorus (P). Whether this shift is occurring relative to N deposition gradients across the northeastern US has not been investigated. We used(More)
Preliminary data from 45 hemlock woolly adelgid monitoring plots across the Northeast indicate that a suite of macronutrients is strongly associated with adelgid infestation and hemlock decline. Although it is unclear whether specific chemical characteristics cause (palatability effect) or result (defensive strategy) from infestation, N, Ca, K, and Mn were(More)
Soil erosion, loss of productivity potential, biodiversity loss, water shortage, and soil and water pollution are ongoing processes that decrease or degrade provisioning (e.g., biomass, freshwater) and regulating (e.g., carbon sequestration, soil quality) ecosystem services. Therefore, developing environmental technologies that maximize these services is(More)
  • 1