Loss of Mass and Chemical Change in Decaying Boles of a Subalpine Balsam Fir Forest

Abstract

Decay of balsam fir (Abies balsamea) boles was examined in an upper subalpine forest of the White Mountains, New Hampshire, USA. Fifty percent of the initial mass was los in 23 yr; 90% was lost in 77 yr. High decay rates were attributed to the small diameters of the boles, ample moisture, and a nitrogen—rich environment. Average dead woods mass in this forest was 4.9 kg/m2, representing 25% of the sum of dead wood, live plant biomass, and forest floor organic matter. Changes in density and moisture and in the concentrations and content of various chemical components of the boles were traced over the decay sequence. Changes in the content of cellulose, lignin, carbon and sodium followed loss of mass during decay. Contents of calcium, magnesium, potassium and phosphorus decreased faster than loss of mass in the early stages of decay. Much of this initial loss was ascribed to sloughing of nutrient—rich bark which in these small boles comprised 13% of dry mass. Later in decay, the loss rates of calcium, magnesium and potassium were about the same or slightly less than the loss rate of mass. After a steep initial drop, phosphorus content of the boles remained approximately constant between years 12 and 33. Thereafter the loss rate paralleled loss of mass. Nitrogen content was approximately constant in the first 33 yr after which it declined in parallel with loss of mass.

Decomposition and the annual flux of detritus from fallen timber in tropical mangrove forests

“…Due to the large quantities of wood detritus in most forests and forest streams, wood acts as an important long-term source of energy and nutrients, a site for nitrogen fixation, and a habitat for organisms, as well as modifying the physical structure of forests and streams and changing the patterns of energy and nutrient flows (e.g. Lambert et al 1980;Bilby and Likens 1980;Triska et al 1984).…”

“…see Lambert et al 1980). Briefly, a 50-m tape was laid in a straight line through the forest and two observers moved along the tape scoring the length and diameter of each dead trunk, prop root, branch, and twig which lay within 1 m of either side of the transect line.…”

The impacts of forest management activities on carbon stocks and sequestration in the Aleza Lake Research Forest.

“…This pattern has been observed in undisturbed (Lambert et al 1980), naturally disturbed (Lee et al 1997;Sturtevant et al 1997;Tyrrell and Crow 1994;Hely et al 2000) and in clearcut forest (Sturtevant et al 1997) chronosequences.…”

“…In northern forests, a general 'u '-shaped pattern of woody debris biomass or volume accumulation is often found along forest chronosequences (Lambert et al 1980;Agee and Huff 1987;Spies et al 1988). The 'u '-shaped pattern describes the relationship between the addition of new woody debris and the decay of existing woody debris.…”

Sustainable Forest Management in a Disturbance Context: A Case Study of Canadian Sub-Boreal Forests

“…From a nutrient perspective, a major difference between timber harvesting and wildfire disturbance is the biomass of woody debris (WD) left in the ecosystem, and the quantity of nutrients removed. WD, particularly coarse woody debris (CWD), has been shown to be an important structural and functional element in many forested ecosystems (Lambert et al, 1980;Sollins, 1982;Harmon et al, 1986;Spies et al, 1988). It provides a key habitat component (especially large logs) for many forms of wildlife (Reynolds et al 1992).…”