State Water Resources Research Institute Program
Project ID: 2006VT27B
Title: Phosphorus availability from the soils along two streams of the Lake Champlain Basin: mapping, characterization and seasonal mobility
Project Type: Research
Start Date: 3/01/2006
End Date: 2/29/2008
Congressional District: First
Focus Categories: Nutrients, Non Point Pollution, Water Quality
Keywords: phosphorus, soil, sediment, soil survey, soil test, P transport, P index
Principal Investigators: Ross, Donald (University of Vermont); Tilley, Joel P.
Federal Funds: $ 8,000
Non-Federal Matching Funds: $ 13,2641
Abstract: Nonpoint source phosphorus (P) inputs into lakes and streams can be a major source of nutrient loading. A critical need is a better understanding of the relative importance of various P sources (e.g. sediment from streambank erosion, runoff from agricultural fields, or release from aquatic sediments). The use of the soil survey in Vermont (VT) to estimate P loading is limited by outdated soils mapping and a lack of information on P concentrations among soil series. We will perform an extensive remapping, soil sampling and P analysis along two VT streams in the Lake Champlain Basin?Lewis Creek and Rugg Brook. Results will include a new digital soils map of the restoration sites, and a data layer that includes total P concentration and a range of availability indices. Intensive studies will be performed on areas along each stream where restoration projects are underway. These studies will provide more detailed soils mapping and characterize the spatial variability of soil P. Soil and sediment P availability will be evaluated with routine extractions and tests designed to estimate P desorption to runoff water. In addition, field and laboratory studies will assess the P release potential from soils and sediments under low oxygen conditions. Laboratory-based measures of P solubility will be compared to P concentrations in the field to determine the utility of laboratory measures as indicators of in situ P release. Phosphorus concentrations in stream channel sediments of differing physical properties will also be characterized. Results will develop and refine relationships between soil P fractions and produce simple predictive models of total and potentially mobile P forms. This will be a collaborative effort between UVM researchers and NRCS soil scientists. Results will enhance understanding of the relationships among soil P availability, P release to runoff and porewaters, and P mobility in floodplain areas.
Progress/Completion Report, PDF