| Type of Document |
Dissertation |
| Author |
Kelly, Charlene Nicole
|
| Author's Email Address |
kellycn@vt.edu |
| URN |
etd-04142010-123554 |
| Title |
Carbon and nitrogen cycling in watersheds of contrasting vegetation types in the Fernow Experimental Forest, West Virginia
|
| Degree |
PhD |
| Department |
Forestry |
| Advisory Committee |
| Advisor Name |
Title |
| Schoenholtz, Stephen H. |
Committee Chair |
| Adams, Mary Beth |
Committee Member |
| Berry, Duane F. |
Committee Member |
| Burger, James A. |
Committee Member |
| Webster, Jackson R. |
Committee Member |
|
| Keywords |
- Fernow Experimental Forest
- nitrogen cycling
- forest soils
- Norway spruce
- vegetation conversion
|
| Date of Defense |
2010-04-01 |
| Availability |
unrestricted |
Abstract
Increased anthropogenic deposition of nitrogen (N) and land-use changes associated with planted forests have important implications for sustainable forest management and associated water quality. The purpose of the research for this dissertation was to explore how N deposition will affect the long-term health, productivity, and carbon (C) and N sequestration of conifer and hardwood forest types by examining the mechanisms controlling N cycling and NO3-N production in two watersheds with contrasting vegetation at the Fernow Experimental Forest (FEF), West Virginia. I utilized watershed C and N budgets to account for differences in stream export of NO3-N from streams draining adjacent watersheds containing (i) planted Norway spruce (Picea abies) and (ii) native Appalachian hardwoods. I also investigated spatial and temporal patterns of dissolved C and N across both watersheds and identified key soil properties associated with NO3-N in soil solution and streamwater. In a third study, I performed a soil inoculation and incubation experiment, which utilized soil from both watersheds, mixed in ratios in order to create a gradient of soil chemical and biotic characteristics. Important differences in biogeochemical cycling of C and N were documented in the watersheds after nearly 40 years of influence by contrasting vegetation. Total C and N pools were 28% and 35% lower in the spruce watershed than the hardwood watershed, respectively. Results also identify vegetation-mediated differences in soil characteristics, with lower soil pH and base cations, and higher extractable aluminum and C:N ratios measured in the spruce soil as compared to the native hardwood soil. Establishment of a spruce monoculture at the FEF significantly altered N cycling, depleted N stores, increased soil acidity, and altered organic matter dynamics, thus leading to low net nitrification rates. Carbon and N properties and processes in the soil profile should be taken into consideration in forests managed for ecosystem services including C sequestration and improvement or maintenance of water quality through alleviation of N inputs into aquatic ecosystems.
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| Files |
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Size |
Approximate Download Time
(Hours:Minutes:Seconds)
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| 28.8 Modem |
56K Modem |
ISDN (64 Kb) |
ISDN (128 Kb) |
Higher-speed Access |
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Kelly_CN_D_2010.pdf |
1.23 Mb |
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