J.G. Crock, and

• Main Author: W. C. Day
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Fortymile River; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.215.247; http://wwwbrr.cr.usgs.gov/projects/GWC_chemtherm/Arsenic/FinalAbsPDF/gough.pdf

Background--Biogeochemical investigations of As transport and uptake by vegetation are being conducted over a metamorphic and intrusive terrane of the Fortymile River watershed of eastern Alaska. The occurrence of As in eolian sub-arctic soils is examined, as well as its relative bioconcentration in willow and alder. This information is used by land managers to assess the importance of geogenic vs. anthropogenic metal sources of environmentally important trace elements in multi-use areas where mining, recreation, and ecosystem preservation are important land-use options (Wanty and others, 2000). Study sites were located on Paleozoic (?) metamorphosed plutonic (supracrustal) metavolcanic and metasedimentary rocks (and associated marble units), and the younger (Jurassic) monzodioritic and tonalitic rocks (Day and others, 2000; Gamble and others, 2001). Samples of A, B, and C soil horizons (Cryaquepts/Cryochrepts), willow (Salix glauca) and alder (Alnus crispa) leaf and twig tissue, and feather moss (Hylocomium splendens) were collected at 36 sites within the lower part of the main-stem of the Fortymile River (~600 km 2 area; fig. 1). The relative contribution to this ecosystem of As from five major rock units was ascertained by the evaluation or rock and soil chemistry and by element uptake by plants.