Title:	Professor Emeritus of Forest Hydrology
	Phone: Fax:	814-863-0291 814-865-3378
	Email:	drdewalle@psu.edu
	Address:	The Pennsylvania State University School of Forest Resources 311 Forest Resources Building University Park, PA 16802

Education:

B.S., University of Missouri (1964), Cum laude

M.S., University of Missouri (1966)

Ph.D., Colorado State University (1969)

Academic Interests:

Forest hydrology; forest microclimatology; snow hydrology; and impacts of ecosystem disturbances: atmospheric deposition, urbanization, and climate change

Affiliated Programs:

 

Penn State Institutes of the Environment; Pennsylvania Water Resources Research Center; Center for Watershed Stewardship.

Courses Taught:

Professional Affiliation:

American Water Resources Association, President 2006
Universities Council on Water Resources
Western Snow Conference
American Geophysical Union
International Association of Hydrologic Sciences

Recent Research/Educational Projects:

Stream Chemistry Response to Atmospheric Deposition
Long-term trends and episodic changes in stream chemistry and aquatic biota are being monitored on five Pennsylvania forested basins to help assess the effects of reductions in atmospheric emissions promulgated by the 1990 Clear Air Act Amendments with funding from the EPA, Corvallis, OR.

Dendrochemical Detection of Soil Acidification
The chemical element content in annual growth rings of hardwood and coniferous trees is being used to indicate the magnitude and timing of soil chemical changes due to fertilization and acidification by simulated atmospheric deposition on a forested watershed at the Fernow Experimental Forest in cooperation with USDA, Forest Service, Parsons, WV. Recently completed a book summarizing research at the Fernow.

Stable Isotope Hydrology
Stable isotopes of are being used to trace the sources and pathways for water and nitrate, as well as compute mean residence times of subsurface waters, on forested and mixed land-use watersheds in Pennsylvania with support from the USGS, PA Water Resources Research Center.

Snow Hydrology
Methods are being developed to improve snowmelt computations and the early-season prediction of streamflow from snowmelt using SNOTEL telemetry records of snowpack water equivalent data from remote, high elevation stations in the Upper Rio Grande basin of Colorado in cooperation with the USDA, Agricultural Research Service in Las Cruces, NM. Also writing a text book on Snow Hydrology with Dr. A. Rango, USDA, ARS, Las Cruces, NM.

Selected Publications:

Adams, M. D., D. R. DeWalle, and J. L. Hom (Ed.). 2006. The Fernow Watershed Acidification Study: Environmental Pollution, Vol 11, Springer, 279p.

O'Driscoll, M. A., D. R. DeWalle, K. J. McGuire, and W. J. Gburek. 2005. Seasonal 18O variations and groundwater recharge for three landscape types in central Pennsylvania, U.S.A. J. Hydrol. 303(1-4):108-124

Willard, K. W. J., D. R. DeWalle, P. J. Edwards. 2005. Influence of bedrock geology and tree species composition on stream nitrate concentrations in mid-Appalachian forested watersheds. Water, Air, and Soil Pollution 160 (1-4):55-76.

DeWalle, D. R., J. A. Eismeier, and A. Rango. 2004. Early forecasts of snowmelt runoff using SNOTEL data in the Upper Rio Grand basin. pp. 17-22 Proc. 71st Annual Meeting, Western Snow Conf., April 19-24, 2004, Scottsdale, AZ. 152 p.

 

DeWalle, D.R., A. R. Buda, and A. Fisher. 2003. Extreme weather and forest management in the Mid-Atlantic Region of the United States. N. J. Applied Forestry 20(2):61-70.

McGuire, K. J., D. R. DeWalle, and W. J. Gburek. 2002. Evaluation of mean residence times in subsurface waters using oxygen- 18 fluctuations during drought conditions in the mid-Appalachians. J. Hydrol. 261(2002):132-149.