Title: Evaluating the phosphorus dynamics in response to restoring historic hydrology at reclaimed wetlands along Upper Klamath Lake, OR.
Project Type: Research
Start Date: 02/15/006
End Date: 02/14/2007
Congressional District: 2, 4
Focus Categories: Water Quality , Agriculture, Groundwater
Keywords: Wetland Restoration, Phosporus dynamics
Principal Investigator: Tullos, Desiree D. (Oregon State University)
Federal Funds: $14,999
Non-Federal Matching Funds: $35,648
Abstract: Upper Klamath Lake (Oregon; UKL) is hypereutrophic due to phosphorus (P) loading from both geologic and agricultural sources in the watershed. According to ODEQ's TMDL analysis, it is elevated P levels that drive severe algal blooms causing pH and dissolved oxygen to often reach toxic levels for fish in the lake. Restoring historic lake-fringe wetlands to provide P sinks around the lake is accepted as a favorable means of reducing lake P levels and loading. However, the capacity of restoration wetlands to sequester P is uncertain because of highly organic soils in these areas that were drained and fertilized over the last century. Previous studies demonstrated that dramatic P releases can occur after these soils are reflooded presumably as a result of organic P mineralization. Our study will quantify changes in form and concentration of soil P as and after levees are breached and natural hydrology is restored to two reclaimed agricultural fields adjacent to UKL. We will also measure changes in soil and floodwater characteristics to better understand the mechanisms of P sequestration and release. Globally, results will: (1) contribute to a more thorough understanding of wetland phosphorous dynamics; and (2) target strategies to promote phosphorus sequestration in restoration wetlands. Locally, these results will expedite water quality improvements in Upper Klamath Lake by providing a foundation to develop management strategies that sequester P in restored wetlands adjacent to UKL.
Progress/Completion Report, PDF