Age-related Decline in Forest Ecosystem Growth: An Individual-Tree, Stand-Structure Hypothesis

Characteristic features of European woodland include both a reduction in natural forest areas and an increase in former agricultural areas occupied by secondary woodland. The management of these areas is challenging in terms of nature conservation, agricultural and forestry management and policy. The aim of our study was to reconstruct the history and to document the current tree stand structure for a secondary oak-beech woodland in Hungary. Towards the end of the 1800s, this area which was once almost completely occupied by a continuous forest, had been transformed into a wood-pasture. As a result of its gradual abandonment, the closed forest stand of the pasture increased from 10 to 52% between 1963 and 2005. The most characteristic feature of this woodland is the abundance of large trees. Globally, the number of large and ancient trees is rapidly diminishing. Therefore preserving and maintaining such areas, where large trees could live, is an essential management task.

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Macromycetes in communities of Abies alba on its range border in central Poland

Acta Mycologica ◽

10.5586/am.2005.011 ◽

2014 ◽

Vol 40 (1) ◽

pp. 113-131

Author(s):

Jarosłaaw Szkodzik

Keyword(s):

Statistical Analysis ◽

Plant Communities ◽

Stand Structure ◽

Abies Alba ◽

Silver Fir ◽

Tree Stand ◽

Northern Limit ◽

Central Poland ◽

Tree Stand Structure ◽

First Time

The paper presents results of mycocoenological examinations conducted in four nature reserves with Abies alba in Central Poland (Lubiaszów, Kruszewiec, Łaznów and Gałków) in 1997-1999. A list of 288 fungi accompanying silver fir communities close to the northern limit of the occurrence of the species, including 38 species identified in associations with Abies alba in Poland for the first time, is given. Statistical analysis has shown that a relationship exists between macromycete diversity, tree stand structure and plant communities such as Tilio-Carpinetum, Luzulo pilosaee-Fagetum, Pino-Quercetum abietetosum.

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The estimation of carbon budgets of frequently burnt tree stands in savannas of northern Australia, using allometric analysis and isotopic discrimination

Australian Journal of Botany ◽

10.1071/bt04150 ◽

2005 ◽

Vol 53 (7) ◽

pp. 621 ◽

Cited By ~ 51

Author(s):

G. D. Cook ◽

A. C. Liedloff ◽

R. W. Eager ◽

X. Chen ◽

R. J. Williams ◽

...

Keyword(s):

National Park ◽

Carbon Isotope Discrimination ◽

Stand Structure ◽

Carbon Stocks ◽

Allometric Relationships ◽

Tree Stand ◽

Cross Sectional ◽

Tree Stand Structure ◽

Allometric Analysis ◽

The Impact

The stock, rates of sequestration and allocation of carbon were estimated for trees in 14 0.1-ha plots at Kapalga in Kakadu National Park, Northern Territory, using new allometric relationships of carbon stock to stem cross-sectional area and measured growth rates of trees. Carbon stocks of trees ranged from 12 to 58 t ha–1, with sequestration representing ~9% of the total stocks. More than half of the sequestered carbon is allocated to leaves and twigs and ~20% to wood. Only ~25% is retained in the live trees with leaf and twig fall accounting for 80%–84% of the total transfers to the environment. An alternative method of calculating sequestration rates from consideration of water use and carbon-isotope discrimination data had a close to 1 : 1 match with estimates from allometric relationships. We developed and applied algorithms to predict the impacts of fire on carbon stocks of live trees. This showed that the reduction in live carbon stocks caused by single fires increased with increasing intensity, but the impact was highly dependent on the tree stand structure.

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Développement d'un modèle de type arbre appliqué à la croissance des peuplements feuillus irréguliers du sud de la Belgique

Canadian Journal of Forest Research ◽

10.1139/x26-209 ◽

1996 ◽

Vol 26 (10) ◽

pp. 1838-1848 ◽

Cited By ~ 1

Author(s):

P. Lejeune

Keyword(s):

Stand Structure ◽

Basal Area ◽

Tree Stand ◽

Individual Tree ◽

Growing Period ◽

Site Characteristics ◽

Individual Tree Growth ◽

Forest Mensuration ◽

Individual Trees ◽

Changes Over Time

A model predicting circumference growth of individual trees has been developed for mixed irregular stands dominated by Fagussilvatica L. in southeastern Belgium. This model integrates simultaneously tree, stand, and growing site characteristics without considering distances between individual trees. It has a determination coefficient of 40.1% and a residual standard deviation of 0.45 cm/year. Forest mensuration variables considered in the model are circumference, tree social position represented by the total basal area of trees greater than the subject tree, stand basal area, and some index of stand structure corresponding to the ratio of the variance over the mean circumference. The site component is essentially expressed by the length of the growing period. The low accuracy obtained for individual tree growth is relative because the results are used mainly after individual trees have been distributed into size classes. We have been able to show that the introduction of crown description in the model can increase its accuracy. But this modification requires a submodel describing crown changes over time.

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Age-related decline of stand biomass accumulation is primarily due to mortality and not to reduction in NPP associated with individual tree physiology, tree growth or stand structure in a Quercus-dominated forest

Journal of Ecology ◽

10.1111/j.1365-2745.2011.01933.x ◽

2012 ◽

Vol 100 (2) ◽

pp. 428-440 ◽

Cited By ~ 54

Author(s):

Cheng-Yuan Xu ◽

Matthew H. Turnbull ◽

David T. Tissue ◽

James D. Lewis ◽

Rob Carson ◽

...

Keyword(s):

Tree Growth ◽

Stand Structure ◽

Biomass Accumulation ◽

Tree Physiology ◽

Individual Tree ◽

Age Related

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Pathogens and insects in a pristine forest ecosystem: the Sierra San Pedro Martir, Baja, Mexico

Canadian Journal of Forest Research ◽

10.1139/x01-219 ◽

2002 ◽

Vol 32 (3) ◽

pp. 448-457 ◽

Cited By ~ 24

Author(s):

Patricia E Maloney ◽

David M Rizzo

Keyword(s):

Forest Ecosystem ◽

Bark Beetles ◽

Stand Structure ◽

Linear Regression Analysis ◽

Mixed Conifer ◽

San Pedro ◽

White Fir ◽

Sugar Pine ◽

Sierra San Pedro Martir ◽

Pristine Forest

We determined the incidence of pathogens and insects across mixed-conifer stands in the Sierra San Pedro Martir (SSPM) of northern Baja, Mexico, to assess the role of pests in a pristine forest ecosystem. We also determined the spatial distribution of the two most common pests, mistletoe, Phoradendron pauciflorum Torrey, and the fir engraver, Scolytus ventralis LeConte, of white fir (Abies concolor (Gord. & Glend.) Lindl.) across a 25-ha grid to assess spread and what host and pest variables were related. In these open parklike stands the mean tree density was 160 trees/ha, of which 58% were trees >20 cm diameter at breast height (DBH). In these low-density, mixed-aged stands we found that mixed-conifer species were well represented with no one species being completely dominant. Percent cumulative mortality for the SSPM was 12.7%, ranging from 2 to 24%, with the greatest amount of mortality occurring in the larger size classes, trees [Formula: see text]50 cm DBH. Multiple linear regression analysis showed that 78% of the mortality we observed was explained by pathogens and bark beetles (r2 = 0.78, P = 0.0001, F = 84). Mean pest incidence for Jeffrey pine (Pinus jeffreyi Grev. & Balf. in A. Murray), white fir, and sugar pine (Pinus lambertiana Dougl.) was 21, 88, and 2%, respectively. We found a number of relationships among host and pest variables, as well as a pathogen insect interaction, and across the SSPM we found that nonhost species may be interfering in certain hostpest interactions. Spatial patterns from the 25-ha grid survey revealed that both P. pauciflorum and S. ventralis incidence were widespread. Phoradendron pauciflorum showed no spatial structure across the 25 ha but S. ventralis showed some degree of spatial structuring across the survey area. We also found that mistletoe severity was negatively correlated with regeneration of white fir. In pristine forests, pathogens and insects influence mortality and regeneration success, affecting stand structure and composition.

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Stand structure links up canopy processes and forest management

Forestry Studies / Metsanduslikud Uurimused ◽

10.2478/v10132-011-0076-8 ◽

2009 ◽

Vol 51 (1) ◽

pp. 40-48

Author(s):

Toomas Frey

Keyword(s):

Forest Management ◽

Stand Structure ◽

Net Primary Production ◽

Stand Density ◽

Tree Height ◽

Belowground Biomass ◽

Unit Mass ◽

Total Biomass ◽

Individual Tree ◽

Mean Values

Stand structure links up canopy processes and forest management Above- and belowground biomass and net primary production (Pn) of a maturing Norway spruce (Picea abies (L.) Karst.) forest (80 years old) established on brown soil in central Estonia were 227, 50 and 19.3 Mg ha correspondingly. Stand structure is determined mostly by mean height and stand density, used widely in forestry, but both are difficult to measure with high precision in respect of canopy processes in individual trees. However, trunk form quotient (q2) and proportion of living crown in relation to tree height are useful parameters allowing describe stand structure tree by tree. Based on 7 model trees, leaf unit mass assimilation activity and total biomass respiration per unit mass were determined graphically as mean values for the whole tree growth during 80 years of age. There are still several possible approaches not used carefully enough to integrate experimental work at instrumented towers with actual forestry measurement. Dependence of physiological characteristics on individual tree parameters is the missing link between canopy processes and forest management.

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Fertilized Midrotation-Aged Slash Pine Plantations—Stand Structure and Yield Prediction Models

Southern Journal of Applied Forestry ◽

10.1093/sjaf/13.2.76 ◽

1989 ◽

Vol 13 (2) ◽

pp. 76-80 ◽

Cited By ~ 27

Author(s):

Robert L. Bailey ◽

Thomas M. Burgan ◽

Eric J. Jokela

Keyword(s):

Prediction Models ◽

Stand Structure ◽

Basal Area ◽

Slash Pine ◽

Pine Plantations ◽

Individual Tree ◽

Investment Opportunities ◽

User Friendly ◽

Volume Equations ◽

Soil Groups

Abstract Data from 263 plots in a regional fertilization study of midrotation-aged slash pine plantations were used to fit prediction equations for basal area, trees per acre, stand average dominant height, diameter distributions, and individual tree heights. The equations include N and P fertilizationrates and CRIFF soil groups as predictor variables. The survival model also accounts for the accelerating effect of fusiform rust on mortality rate. Using published tree volume equations, the prediction of volumes by dbh class for fertilized slash pine plantations is now possible. This integratedsystem of equations is available as a user-friendly computer program that can calculate expected yields by diameter class and aid the forester in evaluating investment opportunities that include forest fertilization. South. J. Appl. For. 13(2):76-80.

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Advances in the Derivation of Northeast Siberian Forest Metrics Using High-Resolution UAV-Based Photogrammetric Point Clouds

Remote Sensing ◽

10.3390/rs11121447 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1447 ◽

Cited By ~ 6

Author(s):

Frederic Brieger ◽

Ulrike Herzschuh ◽

Luidmila A. Pestryakova ◽

Bodo Bookhagen ◽

Evgenii S. Zakharov ◽

...

Keyword(s):

High Resolution ◽

Forest Structure ◽

Stand Structure ◽

Structural Information ◽

Carbon Sink ◽

Local Maximum ◽

Window Size ◽

Point Clouds ◽

Percentage Error ◽

Individual Tree

Forest structure is a crucial component in the assessment of whether a forest is likely to act as a carbon sink under changing climate. Detailed 3D structural information about the tundra–taiga ecotone of Siberia is mostly missing and still underrepresented in current research due to the remoteness and restricted accessibility. Field based, high-resolution remote sensing can provide important knowledge for the understanding of vegetation properties and dynamics. In this study, we test the applicability of consumer-grade Unmanned Aerial Vehicles (UAVs) for rapid calculation of stand metrics in treeline forests. We reconstructed high-resolution photogrammetric point clouds and derived canopy height models for 10 study sites from NE Chukotka and SW Yakutia. Subsequently, we detected individual tree tops using a variable-window size local maximum filter and applied a marker-controlled watershed segmentation for the delineation of tree crowns. With this, we successfully detected 67.1% of the validation individuals. Simple linear regressions of observed and detected metrics show a better correlation (R2) and lower relative root mean square percentage error (RMSE%) for tree heights (mean R2 = 0.77, mean RMSE% = 18.46%) than for crown diameters (mean R2 = 0.46, mean RMSE% = 24.9%). The comparison between detected and observed tree height distributions revealed that our tree detection method was unable to representatively identify trees <2 m. Our results show that plot sizes for vegetation surveys in the tundra–taiga ecotone should be adapted to the forest structure and have a radius of >15–20 m to capture homogeneous and representative forest stands. Additionally, we identify sources of omission and commission errors and give recommendations for their mitigation. In summary, the efficiency of the used method depends on the complexity of the forest’s stand structure.

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Hydrology of Drained Peatland Forest: Numerical Experiment on the Role of Tree Stand Heterogeneity and Management

Forests ◽

10.3390/f9100645 ◽

2018 ◽

Vol 9 (10) ◽

pp. 645 ◽

Cited By ~ 1

Author(s):

Leena Stenberg ◽

Kersti Haahti ◽

Hannu Hökkä ◽

Samuli Launiainen ◽

Mika Nieminen ◽

...

Keyword(s):

Water Balance ◽

Numerical Experiment ◽

Stand Structure ◽

Three Dimensional ◽

Stem Volume ◽

Tree Stand ◽

Management Scenarios ◽

Site Water ◽

Stand Thinning

A prerequisite for sustainable peatland forestry is sufficiently low water table (WT) level for profitable tree production. This requires better understanding on controls and feedbacks between tree stand and its evapotranspiration, drainage network condition, climate, and WT levels. This study explores the role of spatial tree stand distribution in the spatiotemporal distribution of WT levels and site water balance. A numerical experiment was conducted by a three-dimensional (3-D) hydrological model (FLUSH) applied to a 0.5 ha peatland forest assuming (1) spatially uniform interception and transpiration, (2) interception and transpiration scaled with spatial distributions of tree crown and root biomass, and (3) the combination of spatially scaled interception and uniform transpiration. Site water balance and WT levels were simulated for two meteorologically contrasting years. Spatial variations in transpiration were found to control WT levels even in a forest with relatively low stand stem volume (<100 m3/ha). Forest management scenarios demonstrated how stand thinning and reduced drainage efficiency raised WT levels and increased the area and duration of excessively wet conditions having potentially negative economic (reduced tree growth) and environmental (e.g., methane emissions, phosphorus mobilization) consequences. In practice, silvicultural treatment manipulating spatial stand structure should be optimized to avoid emergence of wet spots.

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