Phytomass and detrital carbon storage during forest regrowth in the southeastern United States Piedmont

1989 ◽  
Vol 19 (1) ◽  
pp. 69-78 ◽  
Author(s):  
Paula M. Schiffman ◽  
W. Carter Johnson

Carbon in soil, forest floor, and phytomass was estimated for two chronosequences of loblolly pine (Pinustaeda L.) plantations, as well as agricultural fields and natural Virginia pine (P. virginiana Mill.) forests. One plantation chronosequence was initiated on postagricultural fields and the other following clearing of natural second-growth pine forests and site preparation. Natural reforestation of old fields over 50–70 years increased carbon storage by about 235%, from about 55 000 to 185 000 kg/ha. Carbon in phytomass accounted for the greatest proportion of the increase (76%), followed by forest floor (13%) and surface soil (10%). Old field plantations stored more carbon than natural forests by approximately 42 000 kg/ha (22%). Virtually all of the gain was in phytomass. The contemporary practice of converting natural forests to plantations yielded only a modest gain in carbon (24%), and this in phytomass scheduled for harvest, not in detritus. The results showed negligible oxidative losses of carbon from soils after harvest and site preparation. Site preparation which includes burning may actually cause slow but long-term increases in detrital carbon as charcoal. Forest floor losses during conversion are largely regained by rotation end. Global carbon models need to be amended to incorporate these findings. Stabilization of the forest land base in the Piedmont foretells a rapidly declining capacity to store carbon at past rates. In terms of carbon gained, the current practice of converting natural forests to plantations is no substitute for the farm to forest conversions of past decades. Whether the southeastern United States Piedmont will continue to act as a net carbon sink depends largely on the balance between gains in detrital carbon, principally from charcoal produced by repeated site preparation, and the extent to which forest products from highly productive plantations are placed in long-term versus short-term storage.

2020 ◽  
Vol 66 (6) ◽  
pp. 653-665
Author(s):  
Hector I Restrepo ◽  
Bin Mei ◽  
Bronson P Bullock

Abstract Timberland ownership has drastically changed in the United States since the 1980s, driven by the divestitures of vertically integrated forest products companies. Having sold their timberland, forest products companies have exposed themselves more to the risk of raw material supply. To hedge against this risk, forest products companies usually use long-term timber contracts (LTTC). The objective of this article is to update the valuation framework for LTTCs proposed by Shaffer (1984) by including alternative option price models and refining the estimates of some key economic variables. In particular, conditional volatility from the generalized autoregressive conditional heteroscedasticity model and quasi-conditional volatility from rolling estimation windows, in addition to simple standard deviation, are used for the volatility estimates in the option pricing models. Contrary to the previous result by Shaffer (1984), our analysis suggests that LTTCs that were once profitable for forest products companies in the 1980s are no longer so under current market conditions. This is primarily because both timber price volatility and the risk-free interest rates have declined significantly. Thus, to be better off, forest products companies need to either lower the administration and management costs of those LTTCs or rely more on the open market for timber procurement. Study Implications: Forest products companies have traditionally relied on long-term timber contracts (LTTC) negotiated with forest landowners to mitigate the risk of raw material supply. The value of these LTTCs highly depends on the economic context. This research provides some insights into the valuation of LTTCs in the southeastern United States. Forest products companies can use this updated framework to aid their decisionmaking in timber procurement.


TAPPI Journal ◽  
2013 ◽  
Vol 12 (1) ◽  
pp. 45-50 ◽  
Author(s):  
LAURENCE SCHIMLECK ◽  
KIM LOVE-MYERS ◽  
JOE SANDERS ◽  
HEATH RAYBON ◽  
RICHARD DANIELS ◽  
...  

Many forest products companies in the southeastern United States store large volumes of roundwood under wet storage. Log quality depends on maintaining a high and constant wood moisture content; however, limited knowledge exists regarding moisture variation within individual logs, and within wet decks as a whole, making it impossible to recommend appropriate water application strategies. To better understand moisture variation within a wet deck, time domain reflectometry (TDR) was used to monitor the moisture variation of 30 southern pine logs over an 11-week period for a wet deck at the International Paper McBean woodyard. Three 125 mm long TDR probes were inserted into each log (before the deck was built) at 3, 4.5, and 7.5 m from the butt. The position of each log within the stack was also recorded. Mixed-effects analysis of variance (ANOVA) was used to examine moisture variation over the study period. Moisture content varied within the log, while position within the stack was generally not significant. The performance of the TDR probes was consistent throughout the study, indicating that they would be suitable for long term (e.g., 12 months) monitoring.


2012 ◽  
Vol 13 (1) ◽  
pp. 45 ◽  
Author(s):  
Sarah M. Weeda ◽  
Norman L. Dart

Cylindrocladium pseudonaviculatum, the causal agent of box blight, has been shown to survive in soil for at least 5 years. The occurrence of microsclerotia in host tissue remains undocumented, making the mechanism for long term survival of this pathogen unclear. If the boxwood blight pathogen has indeed lost or never evolved the ability to produce microslerotia in tissues, one could infer that the pathogen is either less equipped for long term survival in soil than other Cylindrocladium species or the pathogen has evolved another mechanism to enable it to persist in soil. Based on these assumptions, we conducted a histological study to determine the potential role, if any, of microsclerotia in the lifecycle of C. pseudonaviculatum. Accepted for publication 17 February 2012. Published 3 April 2012.


2018 ◽  
Vol 84 (9) ◽  
pp. 559-568 ◽  
Author(s):  
Matthew P. Dannenberg ◽  
Conghe Song ◽  
Christopher R. Hakkenberg

2004 ◽  
Vol 34 (2) ◽  
pp. 303-309 ◽  
Author(s):  
Timo Kuuluvainen ◽  
Raija Laiho

Forest floor microhabitat diversity was studied in old Pinus sylvestris L. dominated forest sites in two regions within the middle boreal vegetation zone in Fennoscandia: in 50 managed forest sites in the Häme region in southwestern Finland and in 45 natural or old selectively logged forest sites in the Kuhmo–Viena region in northeastern Finland and northwestern Russia. The forests in the Häme region are characterized by a long history of forest utilization, while the forests in the Kuhmo–Viena region can be regarded as natural or near natural. The managed forest sites in Häme had significantly lower forest floor microhabitat diversity compared with natural and near-natural forests. Microhabitats that were significantly more scarce in managed versus natural and near-natural forest sites included humps, depressions, decayed wood, and vicinity of decayed wood. On the other hand, even ground was significantly more abundant in managed forest compared with natural and near-natural forest. Microhabitat availability was also reflected in the occurrence of tree saplings growing in different microhabitats. The results suggest that long-term forest utilization has decreased forest floor microhabitat diversity. This has occurred because of a decreased amount of fallen deadwood and, possibly, lack of soil disturbances because of fewer uprootings caused by falling trees.


2009 ◽  
Vol 39 (4) ◽  
pp. 802-813 ◽  
Author(s):  
John Bradford ◽  
Peter Weishampel ◽  
Marie-Louise Smith ◽  
Randall Kolka ◽  
Richard A. Birdsey ◽  
...  

Reliably estimating carbon storage and cycling in detrital biomass is an obstacle to carbon accounting. We examined carbon pools and fluxes in three small temperate forest landscapes to assess the magnitude of carbon stored in detrital biomass and determine whether detrital carbon storage is related to stand structural properties (leaf area, aboveground biomass, primary production) that can be estimated by remote sensing. We characterized these relationships with and without forest age as an additional predictive variable. Results depended on forest type. Carbon in dead woody debris was substantial at all sites, accounting for ∼17% of aboveground carbon, whereas carbon in forest floor was substantial in the subalpine Rocky Mountains (36% of aboveground carbon) and less important in northern hardwoods of New England and mixed forests of the upper Midwest (∼7%). Relationships to aboveground characteristics accounted for between 38% and 59% of the variability in carbon stored in forest floor and between 21% and 71% of the variability in carbon stored in dead woody material, indicating substantial differences among sites. Relating dead woody debris or forest floor carbon to other aboveground characteristics and (or) stand age may, in some forest types, provide a partial solution to the challenge of assessing fine-scale variability.


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