Document Type

Article

Journal/Book Title/Conference

Canadian Journal of Forest Research

Volume

37

Issue

12

Publisher

National Research Council Canada

Publication Date

2007

First Page

2689

Last Page

2700

DOI

10.1139/X07-115

Abstract

This study investigated aboveground pools and fluxes of biomass, carbon (C), and nitrogen (N) in the overstory and understory of a southern Appalachian red spruce (Picea rubens Sarg.) – Fraser fir (Abies fraseri (Pursh) Poir.) forest, following adelgid-induced fir mortality and spruce windthrow. Using fifty 20 m × 20 m plots, stratified by elevation (1700–1900 m), we estimated standing biomass and fluxes of all growth forms from periodic stand inventories (1998–2003), vegetation surveys, and existing or derived allometric equations. Total C and N pools and fluxes were calculated from plant- and tissue-specific C and N concentrations. Total aboveground biomass attained predisturbance values, ranging from 313 Mg·ha–1 at the lower elevations to 204 Mg·ha–1 at the upper elevations. Overstory biomass production (5650 kg·ha–1·year–1) and N uptake (11–15 kg·ha–1·year–1) exceeded earlier reported values, indicating forest recovery. Woody understory accounted for 3% of aboveground biomass, 10% of annual productivity, and 19% of total N uptake (~7 kg·ha–1·year–1). Herbaceous vegetation, which comprised only 1% of total biomass, took up 18–21 kg N·ha–1 annually, >50% of total ecosystem N uptake (37 kg·ha–1·year–1). This suggests that N-rich understory vegetation plays an important role in N cycling.

Comments

Originally published by the National Research Council - Canada. Publisher's PDF and HTML fulltext can be accessed through the Canadian Journal of Forest Research.