Variation in overstory nitrogen uptake in a small, high-elevation southern Appalachian spruce-fir watershed
Barker M, Van Miegroet H, Nicholas NS, Creed IF. 2002. Variation in overstory nitrogen uptake in a small, high-elevation southern Appalachian spruce-fir watershed. Canadian Journal of Forest Research. 32:1741-1752
The objective was to determine spatial variability in tree nitrogen (N) uptake in a small high-elevation catchment in the Great Smoky Mountains National Park, and to assess the influence of stand and landscape properties on N uptake. Researchers estimate tree N uptake for fifty 20 × 20 m plots in the Noland Divide Watershed (NDW), considering components such as stem growth, foliage increment, and mortality. The study focuses on measurements of mortality of spruce, fir, and yellow birch (Betula alleghaniensis) from 1993 and 1998 stand inventories; throughfall N flux measured in summers 1998 and 1999; litterfall N return; tissue N analyses; and atmospheric N deposition and root turnover estimates from the literature. On average, spruce accounted for 60% of the total N increment, while fir and birch each accounted for about 20% of the increment. Total litterfall was, on average, 40% needles, 20% deciduous foliage, and 40% twigs, bark, and reproductive tissues. N uptake is correlated with measures of stand structure, but not with elevation or aspect.
- Type
- Journal Article
- Authors
- Barker, M; Van Miegroet, H; Nicholas, N; Creed, I
- Units
- ARD , GRSM
- Keywords
- AIRBIB, APHN, Appalachian Highlands Network, ARD_Park-Air-Info_Collection, Deposition, Great Smoky Mountains National Park, GRSM, GRSM-00175, GRSM-00762, Litter, N uptake, Nitrogen, SER, Southeast Region, Spatial variability, Spruce-Fir Forest, stand, stem growth