In this study we used aquatic bryophytes to monitor the impacts of trace level contamination of heavy metals in aquatic ecosystems in Colorado because bryophytes accumulate zinc, cadmium and lead in a near linear fashion. We tested the initial hypothesis that bryophytes would uptake selenium in a manner similar to other heavy metals.  To test the ability of bryophytes to accumulate selenium, porous nylon bags containing the aquatic bryophyte Hygrohypnum ochraceum were placed at 14 sites in the Fountain Creek Watershed because selenium levels are known to vary along the creek. The plants were exposed to Fountain Creek water for 10 days in the spring and fall of 2007. Samples of water were collected and analyzed three times per site during the ten-day exposure. The plants were recovered from the sites and analyzed for metals by ICP-MS. Twenty six metals and metalloids were monitored These  include calcium, magnesium, iron, lead, arsenic, selenium, nickel, cobalt, copper and zinc.  Analyses of 2010 digests indicate that plant selenium (Se) uptake was significant between Colorado Springs and Pueblo in the spring 2007 with plants showing an accumulation of 160,000 times the total Se in the water in the Lower Fountain Creek area. In the spring, plants showed an accumulation of 100,000 times the total water Se concentration in the Upper Fountain Creek area.  We rejected the initial hypothesis because bryophytes' accumulation of selenium was found to be independent of water selenium concentrations. Based on these results a principle component analysis was performed to identify other correlations. Initial analyses of concurrent levels dissolved iron and selenium in the waters tested point to the involvement of iron in a pH-driven mechanism that may affect Se transport in bryophytes. Our results support an iron dependent mechanism for the selenium accumulation in bryophytes, which may involve the selenium uptake process by bryophytes.?

Bioaccumulation of selenium in the bryophyte<i> Hygrohypnum ochraceum</i> in Colorado

247th National Meeting (2014)

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Bioaccumulation of selenium in the bryophyte Hygrohypnum ochraceum in Colorado