George A. Meindl, PhD
Chemical Ecology
Human activity has led to widespread chemical alteration of natural environments. Aquatic ecosystems are especially susceptible to chemical changes, including those caused by agricultural runoff and invasive species. My students and I study a broad range of study systems and ecological consequences related to anthropogenic chemical contamination in wetland and upland communities. Current projects include Cu phytoremediation by submerged macrophytes and impacts of invasive leaf litter on soil arthropod communities.
Soil Ecology
Geologically unique areas, including serpentine soils, often harbor rare, locally adapted plant species. Serpentine soils, in particular, present a generally stressful growing environment for plants due to a number of edaphic factors, including a low Ca/Mg ratio, low levels of essential plant nutrients, and high concentrations of several heavy metals. For plant species that are able to grow on serpentine soils, these edaphic factors may result in changes in both plant morphology and tissue chemistry. Much of my research program focuses on the extent to which soil chemistry influences both plant morphology and tissue chemistry of flowering plants that vary in their affinity (i.e. endemic vs. non-endemic) to serpentine soil, and whether these changes alter plant reproduction, either through changes in plant-pollinator interactions or gamete function. Studies comparing endemic vs. non-endemic responses to soil conditions provide insight into the nature of edaphic endemism by determining whether endemics are true soil specialists, or rather poor competitors who are simply stress-tolerant.
Metal Hyperaccumulation
Metal hyperaccumulation is a phenomenon described in several hundred plant species, and refers to the uptake and sequestration of high concentrations of heavy metals into aboveground tissues. These interesting plants accumulate orders of magnitude higher metal concentrations than typical plant species. The adaptive value and ecological significance of metal hyperaccumulation for plants, however, is still uncertain. I continue to study the effects of metal accumulation in flowers on plant-pollinator interactions in natural and experimental populations of metal hyperaccumulating plants, with the goal of determining whether metal-rich, toxic pollen and nectar may be adaptive, or rather an unintended consequence of metal accumulation into other tissues. Ongoing projects seek to better understand the adaptive significance of metal
hyperaccumulation (e.g., nutrient scavenging mechanisms, defense against antagonists, etc.).