Current and future applications for forest census data in water resource management

Background/Question/Methods

Multiple factors are important when describing watersheds and the corresponding condition of their waterways.  These factors include topography, climate, geology, and land use.  Forest is a common land use, typically associated with higher quality water and habitat, especially when compared to more developed types of land use.  Forest land use can be expressed most simply as a plot of land or group of pixels with tree cover, but it may also be possible to include more detailed information such as tree species and/or tree density.  Two recent forest data products have been developed by the USDA Forest Service that describe A) persistent and disturbed forest in the western Great Lakes, and B) forest plot data collected by the Forest Inventory and Analysis (FIA) that have been imputed into a continuous spatial database for the Eastern United States.  We describe recent modeling activities that used these forest land use metrics to describe water quality in the watersheds of Lake Superior and Lake Michigan.  We will also suggest future uses for these types of data for research and management of aquatic resources.

Results/Conclusions

Watershed models predicted water quality in the western Great Lakes using metrics for the amount of disturbed forest (1984-1999 and 2000-2009) and softwood forest, along with other land use types, such as urban and agriculture.  Forest metrics with value-added characteristics, like temporal descriptions of disturbance, are increasing utility for describing and predicting the condition of water, as well as aquatic habitat quality.  The spatial relationships between areas of disturbed forest and waters (e.g., riparian buffers) will provide useful avenues for future research.  FIA will continue to integrate forest census information with water science and ecology to maximize the efficiency and cost effectiveness of land protection and restoration.