Skip to Main Content
Rates of nitrogen mineralization across an elevation and vegetation gradient in the Southern AppalachiansAuthor(s): Jennifer D. Knoepp; Wayne T. Swank
Source: Plant and Soil. 204: 235-241.
Publication Series: Miscellaneous Publication
PDF: View PDF (194 KB)
DescriptionThe authors measured nitrogen (N) transformation rates for six years to examine temporal variation across the vegetation and elevation gradient that exists within the Coweeta Hydrologic Laboratory. Net N mineralization and nitrification rates were measured using 28-day in situ closed core incubations. Incubations were conducted at various intervals, ranging from monthly during the growing season, to seasonally based on vegetation phenology. Vegetation types included oak-pine, cove hardwoods, low elevation mixed oak, high elevation mixed oak, and northern hardwoods. Elevations ranged from 782 to 1347 m. Nitrogen transformation rates varied with vegetation type. Mineralization rates were lowest in the oak-pine and mixed oak sites averaging <1.2 mg N kg soil- 1 28 day-- 1. Rates in the cove hardwood site were greater than all other low elevation sites with an annual average of 3.8 mg N kg soil- 1 28 day- 1. Nitrogen mineralization was greatest in the northern hardwood site averaging 13 mg N kg soil- 1 28 day- 1. Nitrification rates were typically low on four sites with rates <0.5 mg N kg soil- 1 28 day- 1. However, the annual average nitrification rate of the northern hardwood site was 6 mg N kg soil- 1 28 days- 1. Strong seasonal trends in N mineralization were observed. Highest rates occurred in spring and summer with negligible activity in winter. Seasonal trends in nitrification were statistically significant only in the northern hardwood site. Nitrogen mineralization was significantly different among sites on the vegetation and elevation gradient. While N mineralization rates were greatest at the high elevation site, vegetation type appears to be the controlling factor.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
CitationKnoepp, Jennifer D.; Swank, Wayne T. 1998. Rates of nitrogen mineralization across an elevation and vegetation gradient in the Southern Appalachians. Plant and Soil. 204: 235-241.
- Releasing red oak reproduction using a growing season application of Oust
- Regulation of nitrogen mineralization and nitrification in Southern Appalachian ecosystems: separating the relative importance of biotic vs. abiotic controls
- Comparing regeneration techniques for afforesting previously farmed bottomland hardwood sites in the Lower Mississippi Alluvial Valley, USA
XML: View XML