Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most sign...

About 50 to 80 percent of precipitation in the southeastern United States returns to the atmosphere by evapotranspiration. As evapotranspiration is a major component in the forest water balances, accurately quantifying it is critical to predicting the effects of forest management and global change on water, sediment, and nutrient yield from forested watersheds. However, direct measurement of fo...

Forest mortality along highways has long been a concern in areas where de-icing compounds are applied during winter. This study combined the spatial advantage of high-resolution remote sensing imagery and the temporal advantage of long-term archival imagery to quantify forest mortality and to detect the subtle and chronic effects of road de-icing salts for a large mountain watershed in the Sier...

Emergy (with an 'm') synthesis was used to assess the balance between nature and humanity and the equity among forest outcomes of a US Forest Service ecosystem management demonstration project on the Wine Spring Creek watershed, a high-elevation (1600 m), temperate forest located in the southern Appalachian mountains of North Carolina, USA. EM embraces a holistic perspective, accounting for the...

We analyzed three kinds of information to evaluate the potential of forests in the Chesapeake Bay watershed to retain the nitrogen in atmospheric deposition. Long-term (13:~) measurements of nitrogen in precipitation and stream discharge for one forested watershed in the Inner Coastal Plain showed consistently high nitrogen retention. Annual wet precipitation deposited an averagk of U.4 kg N/ha...

Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa) plantations account for approximately 30% of the total forested area in Japan. Both are arbuscular mycorrhizal trees that leach more NO3 in response to nitrogen (N) deposition than do forests of ectomycorrhizal trees. However, little information is available about the size of N exports from these plantations. The ...

[1] Land use and physiographic variability influence stream low flows, yet their interactions and relative influence remain unresolved. Our objective was to assess the influence of land use and watershed geomorphic characteristics on low-flow variability in the southern Blue Ridge Mountains of North Carolina and Georgia. Ten minute interval discharge data for 35 streams (in watersheds from 3 to...

PETER B. ADLER*, DANIEL G. MILCHUNAS†, WILLIAM K. LAUENROTH*†, OSVALDO E. SALA‡ and INGRID C. BURKE*† *Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA; †Department of Forest, Rangeland and Watershed Stewardship, Colorado State University, Fort Collins, CO 80523, USA; and ‡Department de Ecología, Facultad de Agronomía, Universidad de Buenos Aires, Avenu...

we studied 11 gaps covered with beech saplings (< 1.30 m tall) in a reserve compartment (compartment 139, district one, langa forest, watershed 36: kazemrood) of the caspian beech forest in n iran. two transects, each 2 m wide, were laid along the longest (n-s) and shortest (e-w) axis of each gap. five micro sample plots, each 4 m2, were established: one at the center, and one at each corner. q...