1 research outputs found
Understanding and Predicting the Fate of Semivolatile Organic Pesticides in a Glacier-Fed Lake Using a Multimedia Chemical Fate Model
Melting
glaciers release previously ice-entrapped chemicals to
the surrounding environment. As glacier melting accelerates under
future climate warming, chemical release may also increase. This study
investigated the behavior of semivolatile pesticides over the course
of one year and predicted their behavior under two future climate
change scenarios. Pesticides were quantified in air, lake water, glacial
meltwater, and streamwater in the catchment of Lake Brewster, an alpine
glacier-fed lake located in the Southern Alps of New Zealand. Two
historic-use pesticides (endosulfan I and hexachlorobenzene) and three
current-use pesticides (dacthal, triallate, and chlorpyrifos) were
frequently found in both air and water samples from the catchment.
Regression analysis indicated that the pesticide concentrations in
glacial meltwater and lake water were strongly correlated. A multimedia
environmental fate model was developed for these five chemicals in
Brewster Lake. Modeling results indicated that seasonal lake ice cover
melt, and varying contributions of input from glacial melt and streamwater,
created pulses in pesticide concentrations in lake water. Under future
climate scenarios, the concentration pulse was altered and glacial
melt made a greater contribution (as mass flux) to pesticide input
in the lake water