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.

Tekstura drzewostanów naturalnych w polskich parkach narodowych na tle teorii dynamiki lasu

2021 ◽  
Author(s):  
Leszek Bartkowicz ◽  
Keyword(s):  
Tree Species ◽  
Stand Structure ◽  
Basal Area ◽  
Site Conditions ◽  
Gap Dynamics ◽  
Old Growth ◽  
Mosaic Pattern ◽  
Spruce Forests ◽  
Old Growth Forest ◽  
Patch Mosaic

The aim of the study was to compare a patch-mosaic pattern in the old-growth forest stands developed in various climate and soil conditions occurring in different regions of Poland. Based on the assumption, that the patch-mosaic pattern in the forest reflect the dynamic processes taking place in it, and that each type of forest ecosystem is characterized by a specific regime of natural disturbances, the following hypotheses were formulated: (i) the patches with a complex structure in stands composed of latesuccessional, shade-tolerant tree species are more common than those composed of early-successional, light-demanding ones, (ii) the patch-mosaic pattern is more heterogeneous in optimal forest site conditions than in extreme ones, (iii) in similar site conditions differentiation of the stand structure in distinguished patches is determined by the successional status of the tree species forming a given patch, (iv) the successional trends leading to changes of species composition foster diversification of the patch structure, (v) differentiation of the stand structure is negatively related to their local basal area, especially in patches with a high level of its accumulation. Among the best-preserved old-growth forest remaining under strict protection in the Polish national parks, nineteen research plots of around 10 ha each were selected. In each plot, a grid (50 × 50 m) of circular sample subplots (with radius 12,62 m) was established. In the sample subplots, species and diameter at breast height of living trees (dbh ≥ 7 cm) were determined. Subsequently, for each sample subplot, several numerical indices were calculated: local basal area (G), dbh structure differentiation index (STR), climax index (CL) and successional index (MS). Statistical tests of Kruskal- Wallis, Levene and Generalized Additive Models (GAM) were used to verify the hypotheses. All examined forests were characterized by a large diversity of stand structure. A particularly high frequency of highly differentiated patches (STR > 0,6) was recorded in the alder swamp forest. The patch mosaic in the examined plots was different – apart from the stands with a strongly pronounced mosaic character (especially subalpine spruce forests), there were also stands with high spatial homogeneity (mainly fir forests). The stand structure in the distinguished patches was generally poorly related to the other studied features. Consequently, all hypotheses were rejected. These results indicate a very complex, mixed pattern of forest natural dynamics regardless of site conditions. In beech forests and lowland multi-species deciduous forests, small-scale disturbances of the gap dynamics type dominate, which are overlapped with less frequent medium-scale disturbances. In more difficult site conditions, large-scale catastrophic disturbances, which occasionally appear in communities formed under the influence of gap dynamics (mainly spruce forests) or cohort dynamics (mainly pine forests), gain importance.

Tree and opening spatial patterns vary by tree density in two old-growth remnant ponderosa pine forests in Northern Arizona, USA

2019 ◽  
Vol 450 ◽  
pp. 117502 ◽  
Author(s):  
Jose M. Iniguez ◽  
James F. Fowler ◽  
W. Keith Moser ◽  
Carolyn H. Sieg ◽  
L. Scott Baggett ◽  
...  
Keyword(s):  
Spatial Patterns ◽  
Ponderosa Pine ◽  
Tree Density ◽  
Pine Forests ◽  
Old Growth ◽  
Ponderosa Pine Forests ◽  
Northern Arizona

Forest Regrowth on the Cumberland Plateau and Implications for Productive Management

1983 ◽  
Vol 7 (4) ◽  
pp. 208-212 ◽  
Author(s):  
Robert N. Muller
Keyword(s):  
Species Composition ◽  
Basal Area ◽  
Stand Density ◽  
Cumberland Plateau ◽  
Old Growth ◽  
Nutrient Pools ◽  
Old Growth Forest ◽  
Composition And Structure ◽  
Second Growth ◽  
Commercial Species

Abstract An old-growth forest and a 35-year-old, second-growth forest on the Cumberland Plateau were studied to compare species composition and structure. Species composition and total basal area of the two stands did not differ, although total stand density was 19 percent lower and basal area of commercial species was 25 percent higher in the old-growth than in the second-growth stand. Analysis of size-class distributions showed that both stands were best represented by an inverse J-shaped distribution, which best describes old-age stands. The rapid regeneration of the second-growth stand seems to be the result of minimal disturbance to accumulated nutrient pools in the soil. The importance of these accumulated nutrient pools and implications for forest management on the Cumberland Plateau are discussed.

scholarly journals Effects of structural retention harvesting on seed production and seed characteristics of old-growth eastern white pine (Pinus strobus L.) stands in northern Ontario

2010 ◽  
Vol 86 (5) ◽  
pp. 614-622 ◽  
Author(s):  
William C. Parker ◽  
Thomas L. Noland ◽  
Brian Brown
Keyword(s):  
Seed Production ◽  
Basal Area ◽  
Pinus Strobus ◽  
White Pine ◽  
Eastern White Pine ◽  
Old Growth ◽  
Partial Harvest ◽  
Old Growth Forest ◽  
Structural Retention ◽  
Seed Characteristics

Seed production and seed characteristics were examined during a mast seeding year in unmanaged, old-growth eastern white pine (Pinus strobus L.) stands located in northeastern Ontario and compared with those in adjacent stands partially harvested 16 years earlier using a structural retention system. Seed yields from old-growth stands were comparable to those of mature, second growth white pine stands but seed production assessed relative to unit area (# ha-1) and pine basal area (# m-2) was lower in partially harvested stands. In both unmanaged and harvested stands, seed production rate of trees growing in localized areas of lower pine basal area was higher. Seed characteristics and seed viability did not differ between harvest treatments. Although structural retention harvesting reduced seed production, results suggest that supply and viability of seed are unlikely to limit seedling recruitment in managed or protected old-growth white pine forests. Key words: germination, old-growth forest, partial harvest, seed mass, seed production

Gradient analysis of old spruce – fir forests of the Great Smoky Mountains circa 1935

1993 ◽  
Vol 71 (7) ◽  
pp. 951-958 ◽  
Author(s):  
R.T. Busing ◽  
P.S. White ◽  
M.D. MacKenzie
Keyword(s):  
Solar Radiation ◽  
Gradient Analysis ◽  
Deciduous Forest ◽  
Basal Area ◽  
Slope Aspect ◽  
Old Growth ◽  
Abies Fraseri ◽  
Great Smoky Mountains ◽  
Old Growth Forest ◽  
Smoky Mountains

The response of old-growth spruce – fir vegetation to environmental gradients was investigated using 1930s plot data from the Great Smoky Mountains. Gradients related to forest composition and position of the ecotone with the deciduous forest were identified using canonical correspondence analysis (CCA) and their role in vegetation response to climate change was considered. The data were subsequently stratified into three elevation classes and ordinated separately using CCA to identify gradients at various elevations. The effect of elevation on tree stratum composition and structure was profound. Secondary gradients influencing the tree stratum included slope aspect, potential solar radiation, and topographic position. Abies fraseri basal area and density were high above 1800 m elevation. Comparable basal area levels of Picea rubens were attained at elevations ranging from 1400 to 1900 m. Total stand basal area and density increased with elevation. The importance of topographic position increased with elevation, while that of slope aspect and potential solar radiation decreased. Presumably, the increasing incidence of cloud cover with elevation diminished the effect of slope aspect and potential solar radiation at higher elevations. The transition from deciduous forest occurred in the 1300 – 1600 m elevation range. A substantial proportion (24%) of plots had mixed composition (30 – 70% spruce – fir by basal area), suggesting that the ecotone is not abrupt in old-growth forest. Environmental variables other than elevation did not have a strong effect on ecotone position. Attempts to infer long-term ecotone dynamics along the elevation gradient based on species size-class data were inconclusive. Key words: Abies fraseri, gradient analysis, Great Smoky Mountains, old-growth forest, Picea rubens, spruce – fir forest.

scholarly journals Recovery of Forest Structure Following Large-Scale Windthrows in the Northwestern Amazon

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 667
Author(s):  
J. David Urquiza Muñoz ◽  
Daniel Magnabosco Marra ◽  
Robinson I. Negrón-Juarez ◽  
Rodil Tello-Espinoza ◽  
Waldemar Alegría-Muñoz ◽  
...  
Keyword(s):  
Forest Structure ◽  
Large Scale ◽  
Tree Mortality ◽  
Basal Area ◽  
Forest Recovery ◽  
Old Growth ◽  
Study Region ◽  
Central Amazon ◽  
Old Growth Forest ◽  
Study Sites

The dynamics of forest recovery after windthrows (i.e., broken or uprooted trees by wind) are poorly understood in tropical forests. The Northwestern Amazon (NWA) is characterized by a higher occurrence of windthrows, greater rainfall, and higher annual tree mortality rates (~2%) than the Central Amazon (CA). We combined forest inventory data from three sites in the Iquitos region of Peru, with recovery periods spanning 2, 12, and 22 years following windthrow events. Study sites and sampling areas were selected by assessing the windthrow severity using remote sensing. At each site, we recorded all trees with a diameter at breast height (DBH) ≥ 10 cm along transects, capturing the range of windthrow severity from old-growth to highly disturbed (mortality > 60%) forest. Across all damage classes, tree density and basal area recovered to >90% of the old-growth values after 20 years. Aboveground biomass (AGB) in old-growth forest was 380 (±156) Mg ha−1. In extremely disturbed areas, AGB was still reduced to 163 (±68) Mg ha−1 after 2 years and 323 (± 139) Mg ha−1 after 12 years. This recovery rate is ~50% faster than that reported for Central Amazon forests. The faster recovery of forest structure in our study region may be a function of its higher productivity and adaptability to more frequent and severe windthrows. These varying rates of recovery highlight the importance of extreme wind and rainfall on shaping gradients of forest structure in the Amazon, and the different vulnerabilities of these forests to natural disturbances whose severity and frequency are being altered by climate change.

scholarly journals The long-term dynamics of the old-growth structure in the National Nature Reserve Badínsky prales

2020 ◽  
Vol 66 (No. 12) ◽  
pp. 501-510
Author(s):  
Ladislav Šumichrast ◽  
Jaroslav Vencurik ◽  
Ján Pittner ◽  
Stanislav Kucbel
Keyword(s):  
Species Composition ◽  
Relative Density ◽  
Detrended Correspondence Analysis ◽  
Basal Area ◽  
Importance Value ◽  
Old Growth ◽  
Stand Volume ◽  
Structure Dynamics ◽  
Old Growth Forest

The main goal of this paper was to evaluate structure dynamics in the fir-beech, old-growth forest Badínsky prales. Measurements were taken on four permanent research plots (0.5 ha each) between 1970 and 2018, typically in ten-year intervals. In order to assess long-term structure dynamics, this study used basic stand characteristics and selected structural indices – the relative density (RD), coefficient of homogeneity (H), and structural complexity index (SCI). Species composition was quantified by the relative importance value (RIV), and a detrended correspondence analysis was carried out for the visualisation of long-term changes. The long-term mean of the stand volume reached 634 ± 99 m3·ha−1, and the mean of the basal area was 36.6 ± 4.0 m2·ha–1. Calculated values of the coefficient of homogeneity (1.46–2.54) were similar to values in other old-growth forests with a comparable tree species composition. An increasing trend in beech RIV values was observed; on the other hand, fir RIV values fell by approximately 20%–25%. In 2018, maximal values of the basal area, stand volume and relative density were recorded. These high values may indicate better growth conditions due to climate change, as well as fewer disturbance events in the last few decades.

Basal area growth impacts of dwarf mistletoe on western hemlock in an old-growth forest

2008 ◽  
Vol 38 (3) ◽  
pp. 576-583 ◽  
Author(s):  
David C. Shaw ◽  
Manuela Huso ◽  
Howard Bruner
Keyword(s):  
Basal Area ◽  
Analysis Of Covariance ◽  
Western Hemlock ◽  
Dwarf Mistletoe ◽  
Old Growth ◽  
Old Growth Forest ◽  
Basal Area Growth ◽  
Initial Diameter ◽  
Large Trees ◽  
Area Growth

We investigated the effect of western hemlock dwarf mistletoe ( Arceuthobium tsugense (Rosend.) G.N. Jones ssp. tsugense ) on the 13 year basal area growth of large (>45.7 cm diameter at breast height) western hemlock ( Tsuga heterophylla (Raf.) Sarg.) trees in an old-growth forest in southwestern Washington state. We controlled for spatial effects on tree growth by utilizing twenty-seven 0.4 ha plots that had uninfected, lightly, moderately, and severely infected classes of trees present on each plot. Basal area growth was analyzed using analysis of covariance of a randomized block design that was a balanced design with four treatments (infection classes) and 27 replicates (blocks or 0.4 ha plots), with initial diameter as the covariate. Basal area growth was found to be significantly different among the infection classes (F[3,77] = 10.09 and p < 0.0001). Growth of the light and moderate infection classes was not detectably different from growth of uninfected trees. However, severely infected trees grew from 16% to 46% (mean = 36%) less than uninfected trees of the same initial diameter over the period of study (1991–2004). The large trees in this stand did not show growth impacts until they were severely infected.

Coarse woody debris in an old-growth deciduous forest on the Cumberland Plateau, southeastern Kentucky

1991 ◽  
Vol 21 (11) ◽  
pp. 1567-1572 ◽  
Author(s):  
Robert N. Muller ◽  
Yan Liu
Keyword(s):  
Coarse Woody Debris ◽  
Total Mass ◽  
Deciduous Forest ◽  
Woody Debris ◽  
Basal Area ◽  
Deciduous Forests ◽  
Cumberland Plateau ◽  
Old Growth ◽  
Regional Pattern ◽  
Old Growth Forest

Volume and mass of coarse woody debris (> 20 cm diameter) in an old-growth forest on the Cumberland Plateau in southeastern Kentucky averaged 66.3 m3/ha and 21.8 Mg/ha, respectively. Coarse woody debris was patchily distributed among 80 sample plots (0.04 ha each), with 10 plots containing 39% of the total mass. Coarse woody debris mass was inversely, although not strongly, related to plot basal area. While 23 species contributed to the accumulation of coarse woody debris, five accounted for 72% of the total mass. These included Quercusprinus L. (25% of the total), Fagusgrandifolia L. (16%), Quercusalba L. (12%), Castaneadentata (Marsh.) Borkh. (11%), and Quercusvelutina Lam. (9%). The few studies of coarse woody debris in old-growth deciduous forests of North America suggest a regional pattern of accumulation correlated with temperature. In warmer regions, old-growth deciduous forests accumulate a mass in the range of 22–32 Mg/ha, while in cooler ecosystems, coarse woody debris ranges from 34 to 49 Mg/ha.

Sign in / Sign up

Export Citation Format

Share Document