Search Results - "DeWalle, D. R."

Evaluation of mean residence time in subsurface waters using oxygen-18 fluctuations during drought conditions in the mid-Appalachians by McGuire, K.J, DeWalle, D.R, Gburek, W.J

“…Seasonal variations of the stable isotope, oxygen-18 ( 18O), were used to estimate mean residence times (MRTs) of water in two Valley and Ridge Province…”
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Tree Response to Experimental Watershed Acidification by Jensen, N. K, Holzmueller, E. J, Edwards, P. J, Gundy, M. Thomas-Van, DeWalle, D. R, Williard, K. W. J

“…Forest ecosystems in the Eastern USA are threatened by acid deposition rates that have increased dramatically since industrialization. We utilized two…”
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Seasonal isotope hydrology of three Appalachian forest catchments by DeWalle, D. R., Edwards, P. J., Swistock, B. R., Aravena, R., Drimmie, R. J.

“…Seasonal oxygen‐18 variations in precipitation, throughfall, soil water, spring flow and stream baseflow were analysed to compare the hydrology of two forested…”
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Episodic Acidification of Small Streams in the Northeastern United States: Effects on Fish Populations by Baker, J. P, J. Van Sickle, C. J. Gagen, D. R. DeWalle, W. E. Sharpe, R. F. Carline, B. P. Baldigo, P. S. Murdoch, D. W. Bath, W. A. Krester, H. A. Simonin, P. J. Wigington Jr

“…As part of the Episodic Response Project (ERP), we studied the effects of episodic acidification on fish in 13 small streams in the northeastern United States:…”
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Seasonal (1)(8)O variations and groundwater recharge for three landscape types in central Pennsylvania, USA by O'Driscoll, M A, DeWalle, D R, McGuire, K J, Gburek, W J

“…Seasonal (1)(8)O variations in precipitation, soil water, snowmelt, spring flow and stream baseflow were analyzed to characterize seasonal dynamics of…”
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Episodic Acidification of Small Streams in the Northeastern United States: Episodic Response Project by Wigington, P. J., Baker, J. P., DeWalle, D. R., Kretser, W. A., Murdoch, P. S., Simonin, H. A., Van Sickle, J., McDowell, M. K., Peck, D. V., Barchet, W. R.

“…The Episodic Response Project (ERP) was an interdisciplinary study designed to address uncertainties about the occurrence, nature, and biological effects of…”
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Prediction of episodic acidification in North-eastern USA: an empirical/mechanistic approach by Davies, T. D., Tranter, M., Wigington Jr, P. J., Eshleman, K. N., Peters, N. E., Van Sickle, J., DeWalle, D. R., Murdoch, P. S.

“…Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the North‐eastern United States are used to develop an…”
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Potential Health Implications for Acid Precipitation, Corrosion, and Metals Contamination of Drinking Water by Sharpe, William E., DeWalle, David R.

“…Potential health effects of drinking water quality changes caused by acid precipitation are presented. Several different types of water supply are discussed…”
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Episodic Acidification of Small Streams in the Northeastern United States: Ionic Controls of Episodes by Wigington, P. J., DeWalle, D. R., Murdoch, P. S., Kretser, W. A., Simonin, H. A., Van Sickle, J., Baker, J. P.

“…As part of the Episodic Response Project (ERP), we intensively monitored discharge and stream chemistry of 13 streams located in the Northern Appalachian…”
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The Effects of Acid Precipitation Runoff Episodes on Reservoir and Tapwater Quality in an Appalachian Mountain Water Supply by Sharpe, William E., DeWalle, David R.

“…The aluminum concentration and Ryznar Index increased and the pH decreased in a small Appalachian water supply reservoir following acid precipitation runoff…”
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Comparison of methods for calculating annual solute exports from six forested appalachian watersheds by SWISTOCK, BRYAN R., EDWARDS, PAMELA J., WOOD, FREDERICA, DEWALLE, DAVID R.

“…Six methods were compared for calculating annual stream exports of sulfate, nitrate, calcium, magnesium and aluminum from six small Appalachian watersheds…”
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Tree-ring cation response to experimental watershed acidification in West Virginia and Maine by DeWalle, D.R, Tepp, J.S, Swistock, B.R, Sharpe, W.E, Edwards, P.J

“…The impact of experimental watershed acidification on xylem cation chemistry was evaluated in eight tree species at two sites in West Virginia (Clover Run and…”
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Stream–air temperature relations to classify stream–ground water interactions in a karst setting, central Pennsylvania, USA by O’Driscoll, Michael A., DeWalle, David R.

“…Stream–ground water interactions in karst vary from complete losses through swallow holes, to reemergences from springs. Our study objective was to compare…”
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Nitrogen export from a watershed subjected to partial salvage logging by Herrmann, M, Sharpe, W E, DeWalle, D R, Swistock, B R

“…Logging has been shown to induce nitrogen (N) leaching. We hypothesized that logging a watershed that previously exhibited forest decline symptoms would place…”
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Indicators of nitrate export from forested watersheds of the mid-Appalachians, United States of America by Williard, K.W.J. (Pennsylvania State University, University Park.), DeWalle, D.R, Edwards, P.J, Schnabel, R.R

“…Soil net nitrogen mineralization and nitrification rates were studied on nine undisturbed, forested watersheds in an effort to explain large variations in…”
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Daytime Habitat Selection by Cottontails in Central Pennsylvania by Althoff, Donald P., Storm, Gerald L., Dewalle, David R.

“…Information on behavioral responses of wildlife to habitat alterations is needed to allow restoration and maintenance of suitable habitats for a variety of…”
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APPLICATION OF THE SNOWMELT RUNOFF MODEL USING MULTIPLE-PARAMETER LANDSCAPE ZONES ON THE TOWANDA CREEK BASIN, PENNSYLVANIA by Mitchell, Kathleen M., DeWalle, David R.

“…The Snowmelt Runoff Model (SRM) is designed to compute daily stream discharge using satellite snow cover data for a basin divided into elevation zones. For the…”
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Channel precipitation dynamics in a forested Pennsylvania headwater catchment (USA) by Crayosky, Travis W., Dewalle, David R., Seybert, Thomas A., Johnson, Thomas E.

“…Seasonal and event variations in stream channel area and the contributions of channel precipitation to stream flow were studied on a 106‐ha forested headwater…”
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The Effects of Acid Precipitation Runoff on Source Water Quality by Leibfried, Robert T., Sharpe, William E., DeWalle, David R.

“…The quality of water in two small streams that provide supplies to the water systems of Jennerstown and Boalsburg, Pa., was monitored during episodes of acid…”
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Guidelines for Riparian Vegetative Shade Restoration Based Upon a Theoretical Shaded-Stream Model by DeWalle, David R

“…Guidelines for riparian vegetative shade restoration were developed using a theoretical model of total daily radiation received by a shaded stream. The model…”
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