|Humenik, F - NC STATE UNIV.|
|Rice, J - NC STATE UNIV.|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 21, 2001
Publication Date: N/A
Technical Abstract: Constructed wetlands can be important for the treatment of swine waste and may also serve as a sink for heavy metals. An experimental treatment wetland system was established in eastern North Carolina in 1993. The levels of copper and zinc were monitored in several of the wetland cells prior to waste application and continued for five years. Soils were sampled once a year at four depths (5-cm increments) along the flow path continuum. The highest accumulation of plant available (Mehlich 3 extraction) copper (5.6 ug/g) and zinc (14.1 ug/g) was noted at the sampling point closest to the inlet of the wetland cell and levels, generally, decreased with progression along the continuum towards the cell outlet. The highest measured levels of both Mehlich-3 copper and zinc were well below the North Carolina Department of Agricultural's cautionary statement level for most crops. These results would indicate that the accumulation of plant available copper and zinc in constructed wetland treating swine waste had a minimal impact on this created ecosystem.