Modeling Landscape Influence on Stream Baseflows for Watershed Conservation

Abstract

Instream flows are vital to the ecology of riverine and riparian systems. The influence of watershed characteristics on these systems is helpful in developing landscape policies to maintain these flows. Watershed characteristics like precipitation, forest cover, impervious cover, soil drainage, and slope affect baseflows. Spatial analysis using GIS and nonlinear regression analysis is used to analyze spatial and temporal information from gauged watersheds in Massachusetts to quantify the relationship between baseflows and watershed metrics. The marginal functions of landscape factors that reflect changes in baseflow are quantified. This information is then applied to watershed policy toward improving base flows. The interactions of three fixed attributes, soil drainage, rainfall incidence, and slope, are analyzed for the manageable landscape attributes of impervious and forest cover. Developing watershed policy to protect baseflows involves evaluating the complex interactions and functional relationships between these landscape factors and their use in watershed conservation planning.