Growth and mortality response of forest regeneration to partial harvesting varies by species’ shade tolerance

2020 ◽  
Vol 50 (10) ◽  
pp. 1081-1092 ◽  
Author(s):  
Arun K. Bose ◽  
Andrew S. Nelson ◽  
Matthew G. Olson
Keyword(s):  
High Intensity ◽  
Natural Regeneration ◽  
Shade Tolerance ◽  
Basal Area ◽  
Permanent Plots ◽  
Partial Harvesting ◽  
Before And After ◽  
Forested Landscapes ◽  
Harvesting Intensity ◽  
Stand Attributes

Does species’ shade tolerance regulate natural regeneration abundance and composition when partial harvestings (≤80% of basal area removal) are operated on a landscape scale? We examined this question using 835 permanent plots located across forested landscapes of Maine, USA. These plots were surveyed for regeneration growth, mortality, and recruitment before and after treatment application (i.e., partially harvested and unharvested). Our results showed that relative to unharvested stands, high-intensity partial harvesting (41%–80% of basal area removal) increased the number of seedlings (diameter at breast height (DBH) < 2.5 cm) recruited to saplings (DBH of 2.5–12.69 cm) and sapling diameter growth irrespective of species’ shade tolerance over a 15-year period after treatment. However, high-intensity partial harvesting increased sapling mortality during the initial 5 years since harvesting, whereas low-intensity partial harvesting (5%–40% of basal area removal) maintained the natural regeneration dynamics (growth, recruitment, and mortality) of unharvested stands. We found that harvesting intensity, basal area, and seedling density by shade-tolerance group before harvesting are more important attributes than species’ shade tolerance for determining the responses of natural regeneration to partial harvesting. The greater importance of preharvest stand attributes on postharvest regeneration may suggest an integrated overstory and understory manipulation approach for attaining the desired regeneration composition.

Croissance de sapinières à bouleau blanc boréales issues de coupe avec protection de la régénération

1992 ◽  
Vol 22 (11) ◽  
pp. 1701-1711 ◽  
Author(s):  
Lucie Bertrand ◽  
Louis Bélanger ◽  
Robert L. Beauregard
Keyword(s):  
Natural Regeneration ◽  
Basal Area ◽  
Balsam Fir ◽  
Growth And Yield ◽  
Permanent Plots ◽  
White Birch ◽  
Second Growth ◽  
Harvesting Method ◽  
Volume Production ◽  
Rotation Age

Models of compatible volume and basal area growth and yield covering a period of 10 to 45 years after harvesting were developed for second growth boreal stands of balsam fir (Abiesbalsamea (L.) Mill.). The 131 permanent plots used for the study were located near Matane, in the Gaspé Peninsula, and are part of the balsam fir–white birch ecoclimatic domain. These stands were harvested in 1934, 1944, and 1953, using a manual cut-and-bunch harvesting method that protected advance growth, and measures were taken in 1954, 1964, and 1978. The stands were moderately affected by spruce budworm outbreaks between 1950–1957 and 1975–1978. Years elapsed since release rather than total age was used as the temporal variable. Even though the characteristics of the coniferous natural regeneration were quite variable, total basal area explained an important part of growth variations of young fir stands by integrating both density and dimensions of the regeneration. Results show, within the limits of the observed densities (< 15 000 stems/ha, 10 years after harvesting), that stands with a higher basal area will have higher total and merchantable volumes at a given age; rotation age for maximum volume production will decrease correspondingly. Abundance of saplings in the initial natural regeneration can thus have an important impact on stand production and rotation age. In the case of nonoverdense young fir stands (< 15 000 stems/ha, 10 years after harvesting with no height growth impediment), the use of spacing treatments that significantly reduce total basal area could be questioned when pursuing maximum fiber production.

Variations in northern white-cedar (Thuja occidentalis) regeneration following operational selection cutting in mixedwood stands of western Quebec

2018 ◽  
Vol 48 (11) ◽  
pp. 1311-1319 ◽  
Author(s):  
Laurence Saucier ◽  
Jean-Claude Ruel ◽  
Catherine Larouche
Keyword(s):  
Basal Area ◽  
Tree Cover ◽  
Permanent Plots ◽  
Thuja Occidentalis ◽  
White Cedar ◽  
Selection Cutting ◽  
Northern White Cedar ◽  
Harvesting Intensity ◽  
Study Sites ◽  
Mixedwood Stands

Poorly adapted silvicultural practices and increases in white-tailed deer (Odocoileus virginianus (Zimmerman, 1780)) populations have most likely contributed to the decline of northern white-cedar (Thuja occidentalis L.) in many regions of eastern North America. Selection cutting has been suggested to regenerate northern white-cedar in mixedwood stands, but the approach has not yet been validated in an operational framework. The objective of this study was to determine how local variations in stand condition and treatment application influence northern white-cedar regeneration at an operational scale in mixedwood stands. Seventy treated and control permanent plots, having at least 10% of basal area in cedar, were selected in an operational harvesting site. A regeneration survey was conducted in 2014, 15 to 20 years after harvesting, and data on harvested trees and tree cover, as well as regeneration state and abundance, were collected. Results indicate that selection cutting allows for the establishment of northern white-cedar when deer densities are low, which was the case in the study sites. However, abundance of seed trees nearby, harvesting intensity, competition, and availability of establishment microsites influenced abundance, growth, and recruitment of northern white-cedar seedlings and saplings in the residual stand. Deer browsing had no effect on regeneration.

Monitoring of natural regeneration in a mixed deciduous forest

1999 ◽  
Vol 64 ◽  
Author(s):  
K. M. Tabari ◽  
N. Lust
Keyword(s):  
Survival Rate ◽  
Natural Regeneration ◽  
Deciduous Forest ◽  
Seedling Stage ◽  
Permanent Plots ◽  
Soil Conditions ◽  
Growing Seasons ◽  
Humus Layer ◽  
Beech Stand ◽  
Regeneration Phase

Monitoring  of natural regeneration in a dense semi-natural mixed hardwood forest on the  base    of ash, beech, oak and sycamore occurred over 3 years in the Aelmoeseneie  experimental    forest, Belgium. 40 permanent plots (4 m x 5 m) were selected in three  various humus types,    located in an ash stand and in an oak - beech stand. In all plots abundance  and top height of all    broad leaved regenerated species were determined at the end of the growing  seasons 1995 and    1998. In addition, the seedlings which appeared in the plots during 1996  and 1997 were    identified and followed up.    This study proves that in the investigated sites natural regeneration is  drastically poor and    diversity is low, in particular where the humus layer is more acidic (mull  moder) and the litter    layer is thick. No regeneration phase older than the seedling stage (h &lt;  40 cm) is developed on    the different humus types. On average, total number of seedlings in 1995  amounts to 38    units/are in the ash stand and to 63 units/are in the oak - beech stand.  Survival rate over a 3-    year period is 37% and 42% respectively in the ash and oak - beech stands.  Total ingrowth    during the growing seasons 1996 and 1997 is virtually poor, indicating 16  and 8 units/are    respectively in above mentioned stands. Survival rate of occurring  seedlings, as well as the ingrowth of new seedlings are notably different (P &lt; 0.05) according to the soil conditions of the    ash stand. Generally, the low presence of seedlings and the lack of  regeneration older than the    seedling stage reveal that the regeneration development encounters with a  critical problem. The    continuation of this process would likely result in a progressive  succession by the invasive and    the unwanted tree species.

scholarly journals Big trees drive forest structure patterns across a lowland Amazon regrowth gradient

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tassiana Maylla Fontoura Caron ◽  
Victor Juan Ulises Rodriguez Chuma ◽  
Alexander Arévalo Sandi ◽  
Darren Norris
Keyword(s):  
Forest Structure ◽  
Natural Regeneration ◽  
Basal Area ◽  
Significant Decline ◽  
Forest Regrowth ◽  
Large Trees ◽  
Amazonian Forests ◽  
Mammal Diversity ◽  
Structure Patterns ◽  
Plot Type

AbstractDegraded Amazonian forests can take decades to recover and the ecological results of natural regeneration are still uncertain. Here we use field data collected across 15 lowland Amazon smallholder properties to examine the relationships between forest structure, mammal diversity, regrowth type, regrowth age, topography and hydrology. Forest structure was quantified together with mammal diversity in 30 paired regrowth-control plots. Forest regrowth stage was classified into three groups: late second-regrowth, early second-regrowth and abandoned pasture. Basal area in regrowth plots remained less than half that recorded in control plots even after 20–25 years. Although basal area did increase in sequence from pasture, early to late-regrowth plots, there was a significant decline in basal area of late-regrowth control plots associated with a decline in the proportion of large trees. Variation in different forest structure responses was explained by contrasting variables, with the proportion of small trees (DBH < 20 cm) most strongly explained by topography (altitude and slope) whereas the proportion of large trees (DBH > 60 cm) was explained by plot type (control vs. regrowth) and regrowth class. These findings support calls for increased efforts to actively conserve large trees to avoid retrogressive succession around edges of degraded Amazon forests.

scholarly journals Modelling natural regeneration of European beech in Saxony, Germany: identifying factors influencing the occurrence and density of regeneration

2021 ◽  
Author(s):  
Maximilian Axer ◽  
Sven Martens ◽  
Robert Schlicht ◽  
Sven Wagner
Keyword(s):  
Natural Regeneration ◽  
Negative Binomial ◽  
European Beech ◽  
Seed Source ◽  
Permanent Plots ◽  
Forest Conversion ◽  
Ecological Knowledge ◽  
Statistical Tool ◽  
Factors Influencing ◽  
The Impact

AbstractThe potential utilisation of natural regeneration of European beech (Fagus sylvatica L.) for forest conversion has received little attention to date. Ecological knowledge is necessary to understand and predict successful natural regeneration of beech. The objective of this study was to improve understanding of what drives the occurrence of beech regeneration and, once regeneration is present, what drives its density. In the study, we utilised a forest inventory dataset provided by Sachsenforst, the state forestry service of Saxony, Germany. The dataset was derived from 8725 permanent plots. Zero-altered negative binomial models (ZANB) with spatial random effects were used to analyse factors influencing occurrence and density simultaneously. The results provided by the spatial ZANB models revealed that the probability of the occurrence of beech regeneration is highly dependent on seed availability, i.e. dependent on source trees in close proximity to a plot. The probability of beech regeneration rises with the increasing diameter of a potential seed tree and decreases with increasing distance to the nearest potential seed source. The occurrence of regeneration is affected by overstorey composition and competition exerted by spruce regeneration. Where sites are affected by groundwater or temporary waterlogging, the impact on the occurrence of regeneration is negative. Although distance to the nearest potential seed source has an influence on occurrence, this variable exerts no influence on density. A high regeneration density arises in conjunction with a high beech basal area in the overstorey. Beech regeneration density, but not occurrence, is negatively affected by browsing intensity. These variables can be used to predict the occurrence and density of beech regeneration in space to a high level of precision. The established statistical tool can be used for decision-making when planning forest conversion using natural regeneration.

Partial cutting reduces species richness of fungi on woody debris in oak-rich forests

2008 ◽  
Vol 38 (7) ◽  
pp. 1807-1816 ◽  
Author(s):  
Björn Nordén ◽  
Frank Götmark ◽  
Martin Ryberg ◽  
Heidi Paltto ◽  
Johan Allmér
Keyword(s):  
Species Richness ◽  
Woody Debris ◽  
Basal Area ◽  
Fruiting Bodies ◽  
Partial Cutting ◽  
Total Species Richness ◽  
Before And After ◽  
Closed Canopy ◽  
And Control ◽  
Total Species

Partial cutting is increasingly applied in European temperate oak-dominated forests for biofuel harvesting, and to counteract succession in protected stands. Effects on biodiversity of these measures need to be carefully evaluated, and species-rich but neglected taxa such as fungi should be considered. We studied the effects of partial cutting on fungal fruiting bodies on woody debris. In 21 closed canopy forests rich in large oaks in Sweden, on average 25%–30% of the basal area was cut. Fruiting bodies were counted and some were collected in treated and control plots before and after treatment. We found 334 basidiomycete and 47 ascomycete species. Species richness of basidiomycetes declined significantly more in treated plots (on average 26%) than in control plots (on average 13%) between seasons. Species richness of ascomycetes increased by 17% in control plots and decreased by 2% in treated plots. Total species richness was significantly reduced on fine woody debris (1–10 cm in diameter), but not on coarse woody debris (>10 cm). Overall species composition did not change significantly as a result of partial cutting, but red-listed species tended to decrease more in treated plots. We suggest that approximately 30% of the stands should not be thinned, and dead stems and fallen branches should not be removed, to favor saproxylic fungi and their associated fauna.

Enhanced sarcoplasmic reticulum Ca2+ release following intermittent sprint training

2000 ◽  
Vol 279 (1) ◽  
pp. R152-R160 ◽  
Author(s):  
Niels Ørtenblad ◽  
Per K. Lunde ◽  
Klaus Levin ◽  
Jesper L. Andersen ◽  
Preben K. Pedersen
Keyword(s):  
Sarcoplasmic Reticulum ◽  
High Intensity ◽  
Vastus Lateralis ◽  
Ryanodine Receptors ◽  
Vastus Lateralis Muscle ◽  
Sprint Training ◽  
High Intensity Training ◽  
Before And After ◽  
Muscle Biopsies ◽  
Intensity Training

To evaluate the effect of intermittent sprint training on sarcoplasmic reticulum (SR) function, nine young men performed a 5 wk high-intensity intermittent bicycle training, and six served as controls. SR function was evaluated from resting vastus lateralis muscle biopsies, before and after the training period. Intermittent sprint performance (ten 8-s all-out periods alternating with 32-s recovery) was enhanced 12% ( P < 0.01) after training. The 5-wk sprint training induced a significantly higher ( P < 0.05) peak rate of AgNO3-stimulated Ca2+ release from 709 (range 560–877; before) to 774 (596–977) arbitrary units Ca2+ ⋅ g protein− 1 ⋅ min− 1(after). The relative SR density of functional ryanodine receptors (RyR) remained unchanged after training; there was, however, a 48% ( P < 0.05) increase in total number of RyR. No significant differences in Ca2+ uptake rate and Ca2+-ATPase capacity were observed following the training, despite that the relative density of Ca2+-ATPase isoforms SERCA1 and SERCA2 had increased 41% and 55%, respectively ( P < 0.05). These data suggest that high-intensity training induces an enhanced peak SR Ca2+ release, due to an enhanced total volume of SR, whereas SR Ca2+ sequestration function is not altered.

Influence of endurance training on muscle [PCr] kinetics during high-intensity exercise

2007 ◽  
Vol 293 (1) ◽  
pp. R392-R401 ◽  
Author(s):  
Andrew M. Jones ◽  
Daryl P. Wilkerson ◽  
Nicolas J. Berger ◽  
Jonathan Fulford
Keyword(s):  
Endurance Training ◽  
High Intensity ◽  
Slow Component ◽  
Knee Extension ◽  
High Intensity Exercise ◽  
Whole Body ◽  
Time To Exhaustion ◽  
Exercise Tests ◽  
Before And After ◽  
Knee Extension Exercise

We hypothesized that a period of endurance training would result in a speeding of muscle phosphocreatine concentration ([PCr]) kinetics over the fundamental phase of the response and a reduction in the amplitude of the [PCr] slow component during high-intensity exercise. Six male subjects (age 26 ± 5 yr) completed 5 wk of single-legged knee-extension exercise training with the alternate leg serving as a control. Before and after the intervention period, the subjects completed incremental and high-intensity step exercise tests of 6-min duration with both legs separately inside the bore of a whole-body magnetic resonance spectrometer. The time-to-exhaustion during incremental exercise was not changed in the control leg [preintervention group (PRE): 19.4 ± 2.3 min vs. postintervention group (POST): 19.4 ± 1.9 min] but was significantly increased in the trained leg (PRE: 19.6 ± 1.6 min vs. POST: 22.0 ± 2.2 min; P < 0.05). During step exercise, there were no significant changes in the control leg, but end-exercise pH and [PCr] were higher after vs. before training. The time constant for the [PCr] kinetics over the fundamental exponential region of the response was not significantly altered in either the control leg (PRE: 40 ± 13 s vs. POST: 43 ± 10 s) or the trained leg (PRE: 38 ± 8 s vs. POST: 40 ± 12 s). However, the amplitude of the [PCr] slow component was significantly reduced in the trained leg (PRE: 15 ± 7 vs. POST: 7 ± 7% change in [PCr]; P < 0.05) with there being no change in the control leg (PRE: 13 ± 8 vs. POST: 12 ± 10% change in [PCr]). The attenuation of the [PCr] slow component might be mechanistically linked with enhanced exercise tolerance following endurance training.

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