Resource Magazine March/April 2014 : Page 5

Odette Mina holds a wood frog tadpole at one of her field sites. Assessing the impact on vernal pool ecosystems Heather Gall and her graduate student, Odette Mina, are interested in understanding the fate of estrogens that are mobi-lized during surface runoff and their potential threat to nearby aquatic ecosystems. There are several vernal pools near the Living Filter that may be impacted by estrogens and other endocrine-disrupting compounds contained in the irrigated wastewater. Vernal pools are important habitats for amphib-ians such as frogs and salamanders, which are currently facing global population declines. Although some laboratory studies have been conducted to understand the impact of controlled exposure of amphibians to emerging contaminants, no data exist for the occurrence of the ECs in vernal pools. Gall, Mina, and their collaborators in Penn State’s Department of Biology (Tracy Langkilde and her graduate student, Bradley Carlson) have identified seven vernal pool sites across an agricultural impact gradient, with the Living Filter sites among those most impacted by agricultural activities. They collected one round of sam-ples in October 2013, when Author Heather Gall with tadpoles. water levels in the pools were low, with the goal of establishing baseline concentra-tions prior to the pools filling up to normal levels. Of the seven sites, only one had detectable levels of estrogens. That is good news for the tadpoles that are developing at these sites, but the absence of estrogens was expected due to their short half-lives and because no recent stormwater runoff events had occurred. These vernal pools receive their water pri-marily from surface runoff rather than ground-water, and Gall’s team hypothesizes that concentrations will increase following snowmelt and runoff events, which are expected to transport estrogens, pesticides, and other ECs. Therefore, more water samples will be collected in the winter and spring to assess the impacts of snowmelt and large spring rainfall events on the presence of estro-gens in these vernal pools. These data will then be used to develop controlled mesocosm experiments, in which tadpoles are exposed to environmentally relevant “contaminant cock-tails.” For more information on Penn State’s Living Filter, visit: A S A B E m e m b e r H e a t h e r G a l l , Assistant Professor,, and H e r s c he l E l l i ot t , Professor,, Department of Agricultural and Biological Engineering, Pennsylvania State University, University Park, USA. Lysimeters being leached after application of wastewater treatment plant effluent. All feature photos courtesy of Tracy Langkilde. RESOURCE March/April 2014 5

Previous Page  Next Page

Publication List
Using a screen reader? Click Here