Abstract

Transport of Non-Point Source Contaminants Through Riparian Wetlands in the Mississippi Delta Region

Author(s): Noakes, E. ;  Davidson, G.;  Wren, D.;  Utroska, S.

A joint research group at the University of Mississippi and the USDA ARS National Sedimentation Laboratory has been investigating the fate and transport of non-point source contaminants entering riparian wetland systems from agricultural lands. Results to date suggest that short-term studies documenting sequestration of chemically persistent contaminants in riparian wetlands are not sufficient to document long-term containment of these substances. In previously reported work, elevated concentrations of Pb and As were found at particular depths in open-water sediments in Sky Lake, but not in contemporaneously deposited sediments in the surrounding wetlands. Depositional dates of the zones of elevated concentration, based on 210Pb and 137Cs measurements, were consistent with the timing of lead arsenate use in the vicinity. The absence of similar concentration spikes in the wetland sediments led to the working hypothesis that contaminants such as Pb and As may be initially scavenged from water flowing through a riparian wetland, but over time are flushed out into adjacent lakes or streams. Within the wetland, seasonal inundation and aeration results in decomposition of litter, remobilization of contaminants bound to organic matter, and redistribution by rising and falling water levels. Permanent sequestration occurs only with burial in the perennially flooded open water environment. The study has been expanded to additional lake-wetland systems in the Mississippi Delta region to determine if evidence of long-term flushing of contaminants from riparian wetlands is a common occurrence.







 

Technical Presentations

  • Delta Water Quality
  • Delta Water and Agriculture
  • Wetlands
  • Water Quality
  • Sediments
  • Non-Point
  • Management and Sustainability
  • Wood Treatment
  • Modeling
  • Soil and Water Treatment

Workshops

Responsible Site Design: Implementing Innovative Stormwater Management Strategies

The primary goal of the workshop is to create a dynamic learning experience that examines the role of stormwater management in the built environment. The workshop will focus on integrating ecologically sound water management approaches into site design. After the workshop, attendees will be familiar with the following concepts and technical issues:

  • Knowledge of the stormwater treatment chain
  • Knowledge of the impact of land use codes on stormwater management
  • Application of a design process that mitigates the effects of stormwater on-site
  • Knowledge of the relationship between land use codes and design for innovative stormwater management

Information

For information contact:
Jessie Schmidt
MWRRI
Box 9680
Mississippi State, MS 39762
662-325-3295
jschmidt@cfr.msstate.edu