scholarly journals Deadwood Characteristics in Mature and Old-Growth Birch Stands and Their Implications for Carbon Storage

Forests ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 536 ◽  
Author(s):  
Silva Šēnhofa ◽  
Ieva Jaunslaviete ◽  
Guntars Šņepsts ◽  
Jurģis Jansons ◽  
Līga Liepa ◽  
...  
Keyword(s):  
Basal Area ◽  
High Volume ◽  
Stand Age ◽  
Old Growth ◽  
Stand Productivity ◽  
Stand Type ◽  
The Difference ◽  
Mineral Soils ◽  
Stand Height ◽  
Mature Stands

As one of the most abundant tree species in the hemiboreal zone, birch is important from both commercial and biodiversity perspectives. While old-growth deciduous stands are important for biodiversity conservation with an emphasis on deadwood availability, the role that deadwood in these stands plays in carbon sequestration remains unclear. We studied mature (71–110 years old) and old-growth (121–150 years old) birch stands on fertile mineral soils. The marginal mean deadwood volume was 43.5 ± 6.4 m3 ha−1 in all mature stands, 51.3 ± 7.1 m3 ha−1 in recently unmanaged mature stands, and 54.4 ± 4.4 m3 ha−1 in old-growth stands; the marginal mean deadwood carbon pool for each stand type was 5.4 ± 0.8 t·ha−1, 6.3 ± 0.9 t·ha−1, and 7.9 ± 0.6 t·ha−1, respectively. Deadwood volume was not related to stand productivity in terms of stand basal area, stand height, or stand age. The difference between mature and old-growth stands remained non-significant (p < 0.05). A high volume of deadwood was almost continuously present throughout the landscape in assessed unmanaged sites; moreover, 88% of sample plots in old-growth stands and 63% of sample plots in mature stands had a deadwood volume higher than 20 m3·ha−1. Old-growth stands had a slightly greater volume of large deadwood than unmanaged mature stands; in both, almost half of the deadwood was more than 30 cm in diameter and approximately one-fifth had a diameter greater than 40 cm. Both groups of stands had similar proportions of coniferous and deciduous deadwood and lying and standing deadwood. Old-growth stands had a higher volume of recently and weakly decayed wood, indicating increased dieback during recent years.

Thinning ponderosa pine (Pinus ponderosa) stands reduces mortality while maintaining stand productivity

2013 ◽  
Vol 43 (4) ◽  
pp. 311-320 ◽  
Author(s):  
Jianwei Zhang ◽  
Martin W. Ritchie ◽  
Douglas A. Maguire ◽  
William W. Oliver
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Bark Beetles ◽  
Basal Area ◽  
Stand Density ◽  
Growth Efficiency ◽  
Stand Age ◽  
Annual Increment ◽  
Stand Productivity ◽  
Residual Variation

We analyzed 45 years of data collected from three ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) levels-of-growing-stock installations in Oregon (OR) and northern California (CA), USA, to determine the effect of stand density regimes on stand productivity and mortality. We found that periodic annual increment (PAI) of diameter, basal area (BA), volume, and aboveground dry mass were significantly related to stand density index (SDI) and stand age at start of the period; the quadratic trends varied among sites. Precipitation departure from the normal for each period explained a significant amount of residual variation in all PAI variables except diameter. BA production did not change significantly as SDI exceeded 270 trees·ha−1 at the OR sites and 320 trees·ha−1 at the CA site. Stand productivity was the highest at Elliot Ranch (CA) and the least at Blue Mountains (OR). A similar trend held in growth efficiency under lower stand densities (SDI < 600). Most of the mortality was caused by Dendroctonus bark beetles in stands that exceeded SDI of 500 trees·ha−1. Limiting SDI was about 900 trees·ha−1, although plots at Elliot Ranch reached much higher than that. The results demonstrate that silvicultural control of stand density can be a powerful tool for reducing bark beetle caused mortality without sacrificing stand productivity.

scholarly journals Availability and Structure of Coarse Woody Debris in Hemiboreal Mature to Old-Growth Aspen Stands and Its Implications for Forest Carbon Pool

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 901
Author(s):  
Silva Šēnhofa ◽  
Guntars Šņepsts ◽  
Kārlis Bičkovskis ◽  
Ieva Jaunslaviete ◽  
Līga Liepa ◽  
...  
Keyword(s):  
Coarse Woody Debris ◽  
Woody Debris ◽  
Age Groups ◽  
High Volume ◽  
Carbon Pool ◽  
Old Growth ◽  
Dead Trees ◽  
European Aspen ◽  
Saproxylic Species ◽  
Mineral Soils

European aspen deadwood is extensively studied as a habitat for saproxylic species, while less is known of its dynamics and role in carbon sequestration. We studied unmanaged mature (41–60 years), moderately overmature (61–80 years), overmature (81–100 years), and old-growth (101–140 years) and managed mature and moderately overmature aspen stands on fertile mineral soils. In unmanaged stands, marginal mean CWD volume was from 67.3 ± 12.1 m3 ha−1 in moderately overmature to 92.4 ± 5.1 m3 ha−1 in old-growth stands, with corresponding marginal mean CWD carbon pool 8.2 ± 1.6 t ha−1 and 12.5 ± 0.7 t ha−1, respectively. Both CWD volume and its carbon pool had substantial yet non-significant differences (all p > 0.05) among the age groups. High CWD volume was present in most stands, by at least two-thirds of plots comprising more than 20 m3 ha−1, and about half of CWD was larger than 30 cm in diameter. Changes in CWD species composition toward a higher proportion of deciduous deadwood in old-growth stands, together with a high volume of recently dead trees, suggest early senescence of the dominant aspen cohort.

The Impact of Balsam Woolly Aphid Damage on Balsam Fir Stands in Newfoundland

1975 ◽  
Vol 5 (2) ◽  
pp. 195-209 ◽  
Author(s):  
G. Page
Keyword(s):  
Basal Area ◽  
Control Measures ◽  
Balsam Fir ◽  
Moisture Regime ◽  
Soil Moisture Regime ◽  
Woolly Aphid ◽  
Stand Height ◽  
Hazard Rating ◽  
Mature Stands ◽  
The Impact

This paper presents data on the effects of balsam woolly aphid damage on the mensurational characteristics of balsam fir trees and stands, and quantitative estimates of changes in merchantable volumes that result from alterations in these characteristics. Average volume losses in damaged semi-mature and mature stands ranged from 2 to 6%, but were as high as 80% or more in a few highly susceptible stands. Strong and consistent relationships were recorded between the incidence and severity of aphid damage and a number of site and stand characteristics, including elevation, soil-moisture regime, stand height and age, balsam fir content and total balsam fir basal area of affected stands, and length of time damage had been present. These relationships were utilized to construct a hazard-rating system for use by forest managers in identifying sites and stands highly susceptible to severe damage, and in scheduling silvicultural control measures.

Has canopy height and biomass recovered 78 years after an intense fire in south-western Australia's red tingle (Eucalyptus jacksonii) forests?

2017 ◽  
Vol 26 (2) ◽  
pp. 148 ◽  
Author(s):  
Grant Wardell-Johnson ◽  
Liam Crellin ◽  
Casey Napier ◽  
Garrett Meigs ◽  
Alyssa Stevenson ◽  
...  
Keyword(s):  
Coarse Woody Debris ◽  
Woody Debris ◽  
Basal Area ◽  
Tree Height ◽  
Canopy Height ◽  
High Carbon ◽  
Old Growth ◽  
Breast Height ◽  
Stand Height ◽  
Carbon Stores

Tall eucalypt old-growth forests are notable for their large, old (i.e. venerable) trees and have both significant conservation value and high carbon stores. We investigated whether canopy height and biomass had recovered in an old-growth red tingle (Eucalyptus jacksonii) forest 78 years after a high-intensity fire. We recorded species, diameter, hollow butting and height of all 596 trees >10-cm diameter at breast height, as well as fine and coarse woody debris, in a 3.55-ha plot near Nornalup, south-western Australia. Pre-fire canopy height was estimated by allometrics derived from tree height and diameter, and diameter and length of recently fallen branches. Of the basal area (75.0 m2 ha–1), 92.7% was eucalypt (chiefly E. jacksonii), with regeneration accounting for only 8.5% of the total. Although canopy species composition apparently did not change following fire, stand height and biomass had not recovered to pre-1937 levels by 2015. Canopy height remained 5.06 m (11%) less and biomass 25% less, 78 years after the fire. The combination of intense fire and a warmer, drier climate appears to have prevented recovery of forest height and structure at this site. These findings indicate that ecologically important, venerable trees are increasingly vulnerable to canopy fire and climate change.

Defining Canada's old-growth forests — problems and solutions

1994 ◽  
Vol 70 (6) ◽  
pp. 739-744 ◽  
Author(s):  
Luc C. Duchesne
Keyword(s):  
Landscape Ecology ◽  
Stand Age ◽  
Anthropogenic Influence ◽  
Annual Increment ◽  
Old Growth ◽  
Site Class ◽  
Old Growth Forests ◽  
Problems And Solutions ◽  
The Difference ◽  
Mean Annual Increment

Conceptual and working definitions of old-growth forests are proposed for Canada. Conceptually, old-growth forests are defined in terms of stand age, structure, species composition, anthropogenic influence, and landscape ecology. Working definitions based on stand age in relation to age of maximum mean annual increment and site class are formulated for Canada's inventoried timber-productive forests. The difference between stand age and the age of maximum mean annual increment is proposed as a measure of old-growthness. Recommendations are made for improving Canada's forest inventory database to help acquire ecological definitions of old-growth forests and monitor and maintain Canada's old-growth heritage. Key words: old-growth forests, stand composition, anthropogenic influence, biodiversity, landscape ecology

Density and diversity of lianas along a chronosequence in a central Panamanian lowland forest

2000 ◽  
Vol 16 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Saara J. Dewalt ◽  
Stefan A. Schnitzer ◽  
Julie S. Denslow
Keyword(s):  
Tropical Forest ◽  
Tropical Forests ◽  
Relative Abundance ◽  
Light Availability ◽  
Basal Area ◽  
Stand Age ◽  
Old Growth ◽  
Lowland Forest ◽  
Abundance And Diversity

The abundance and diversity of lianas were examined along a tropical forest chronosequence at the Barro Colorado Nature Monument, Panama. Lianas ≥0.5 cm diameter were sampled along transects in two replicated stands in secondary (20, 40, 70 and 100 y after abandonment) and old-growth (>500 y) forests. Ordination of stands based on relative abundance, but not presence-absence, showed a significant separation of stands by age. Lianas were significantly more abundant and diverse (Fisher's α) in younger forests (20 and 40 y) than in older forests (70 and 100 y, and old-growth). The decline in liana abundance with stand age was offset by increased mean basal area per individual, resulting in a relatively constant total basal area and estimated biomass across stand age. The proportions of tendril climbers decreased and stem twiners increased over stand age. Decline in liana abundance and changes in liana composition may be related to changes in support and light availability. Although lianas are recognized as playing an important role in the early secondary sucession of many tropical forests, these results have shown that their important contribution to total basal area and biomass can continue as the forest matures, even as the numbers of established lianas declines.

scholarly journals Managing forest harvesting to maintain old growth in boreal and sub-boreal forests

1999 ◽  
Vol 75 (4) ◽  
pp. 623-631 ◽  
Author(s):  
Philip J. Burton ◽  
Daniel D. Kneeshaw ◽  
K. David Coates
Keyword(s):  
Basal Area ◽  
Timber Harvest ◽  
Forest Harvesting ◽  
Stand Age ◽  
Forest Age ◽  
Old Growth ◽  
Partial Cutting ◽  
Growth Status ◽  
Age Class ◽  
Old Growth Forest

Old-growth stands can be rare in northern coniferous forests, and hence are worthy of protection and special management. We describe some quantitative guidelines for recognizing old-growth stands and options for maintaining a long-term supply of old-growth values in landscapes managed for timber production. In the Sub-Boreal Spruce forests of central British Columbia, attributes most indicative of old-growth status include stand age, the density of large (> 1.0 m3) snags and downed logs, stand basal area and volume. It is suggested that partial cutting could occur in some old-growth stands, while still maintaining their structural and functional attributes, if large logs, snags and trees are retained at the threshold densities necessary to recognise old-growth status. At the landscape level, the use of extended timber crop rotations is advocated. Planning for a tapered forest age class distribution (with decreasing areas of forest allowed to persist to successively older ages) is suggested as a means of sustainably generating true old-growth, and as an alternative to the use of partial cutting and patch retention. Arithmetic formulas are developed which provide guidelines for the proportion of the forest land base to be kept in each successive age class. This model for regulating human disturbance in commercial forests holds promise as a mechanism for allowing continued timber harvest and even-aged stand management while retaining a near-natural proportion of old-growth forest in northern landscapes. Key words: disturbance regime, even-aged management, extended rotations, forest age class structure, forest management, old-growth attributes, rotation length, silvicultural systems, sub-boreal spruce zone, timber supply planning.

scholarly journals The Difficulty of Predicting Eastern Spruce Dwarf Mistletoe in Lowland Black Spruce: Model Benchmarking in Northern Minnesota, USA

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 843
Author(s):  
Ella R. Gray ◽  
Matthew B. Russell ◽  
Marcella A. Windmuller-Campione
Keyword(s):  
Stand Structure ◽  
Black Spruce ◽  
Forest Health ◽  
Basal Area ◽  
Predictive Performance ◽  
Stand Age ◽  
Management Decisions ◽  
Dwarf Mistletoe ◽  
Growing Seasons ◽  
Model Interpretation

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.

Variation in canopy gap formation among developmental stages of northern hardwood stands

1996 ◽  
Vol 26 (10) ◽  
pp. 1875-1892 ◽  
Author(s):  
Sally E. Dahir ◽  
Craig G. Lorimer
Keyword(s):  
Sugar Maple ◽  
Tree Mortality ◽  
Developmental Stages ◽  
Turnover Time ◽  
Gap Formation ◽  
Old Growth ◽  
Northern Hardwood ◽  
Hardwood Species ◽  
Shade Tolerant Species ◽  
Mature Stands

Trends in gap dynamics among pole, mature, and old-growth northern hardwood stands were investigated on eight sites in the Porcupine Mountains of western upper Michigan. Recent gaps (created between 1981 and 1992) were identified using permanent plot records of tree mortality, while older gaps (1940–1981) were identified using stand reconstruction techniques. Although canopy gaps were somewhat more numerous in pole and mature stands, gaps were <25% as large as those in old-growth stands because of smaller gap-maker size, and the proportion of stand area turned over in gaps was only about half as large. Gap makers in younger stands generally had mean relative diameters (ratio of gap-maker DBH to mean DBH of canopy trees) <1.0 and were disproportionately from minor species such as eastern hophornbeam (Ostryavirginiana (Mill.) K. Koch). Gap makers in old-growth stands had mean relative diameters >1.5 and were predominantly from the dominant canopy species. Even in old-growth forests, most gaps were small (mean 44 m2) and created by single trees. Based on the identity of the tallest gap tree in each gap, nearly all shade-tolerant and midtolerant species have been successful in capturing gaps, but gap capture rates for some species were significantly different from their relative density in the upper canopy. The tallest gap trees of shade-tolerant species were often formerly overtopped trees, averaging more than 60% of the mean canopy height and having mean ages of 65–149 years. Canopy turnover times, based on gap formation rates over a 50-year period, were estimated to average 128 years for old-growth stands dominated by sugar maple (Acersaccharum Marsh.) and 192 years for old-growth stands dominated by hemlock (Tsugacanadensis (L.) Carrière). While these estimates of turnover time are substantially shorter than maximum tree ages observed on these sites, they agree closely with independent data on mean canopy residence time for trees that die at the average gap-maker size of 51 cm DBH. The data support previous hypothetical explanations of the apparent discrepancy between canopy turnover times of <130 years for hardwood species and the frequent occurrence of trees exceeding 250 years of age.

Geostatistically modeling stem size and increment in an old-growth forest

1994 ◽  
Vol 24 (7) ◽  
pp. 1354-1368 ◽  
Author(s):  
Franco Biondi ◽  
Donald E. Myers ◽  
Charles C. Avery
Keyword(s):  
Spatial Patterns ◽  
Growth Rates ◽  
Spatial Dependence ◽  
Basal Area ◽  
Tree Density ◽  
Individual Growth ◽  
Old Growth ◽  
Model Estimate ◽  
Stem Size ◽  
Old Growth Forest

Geostatistics provides tools to model, estimate, map, and eventually predict spatial patterns of tree size and growth. Variogram models and kriged maps were used to study spatial dependence of stem diameter (DBH), basal area (BA), and 10-year periodic basal area increment (BAI) in an old-growth forest stand. Temporal variation of spatial patterns was evaluated by fitting spatial stochastic models at 10-year intervals, from 1920 to 1990. The study area was a naturally seeded stand of southwestern ponderosa pine (Pinusponderosa Dougl. ex Laws. var. scopulorum) where total BA and tree density have steadily increased over the last decades. Our objective was to determine if increased stand density simply reduced individual growth rates or if it also altered spatial interactions among trees. Despite increased crowding, stem size maintained the same type of spatial dependence from 1920 to 1990. An isotropic Gaussian variogram was the model of choice to represent spatial dependence at all times. Stem size was spatially autocorrelated over distances no greater than 30 m, a measure of average patch diameter in this forest ecosystem. Because patch diameter remained constant through time, tree density increased by increasing the number of pine groups, not their horizontal dimension. Spatial dependence of stem size (DBH and BA) was always much greater and decreased less through time than that of stem increment (BAI). Spatial dependence of BAI was close to zero in the most recent decade, indicating that growth rates in 1980–1990 varied regardless of mutual tree position. Increased tree crowding corresponded not only to lower average and variance of individual growth rates, but also to reduced spatial dependence of BAI. Because growth variation was less affected by intertree distance with greater local crowding, prediction of individual growth rates benefits from information on horizontal stand structure only if tree density does not exceed threshold values. Simulation models and area estimates of tree performance in old-growth forests may be improved by including geostatistical components to summarize ecological spatial dependence.

Sign in / Sign up

Export Citation Format

Share Document