Live tree species basal area of the contiguous United States (2000-2009)

Climate change is expected to impact forests worldwide, and yellow-cedar (Callitropsis nootkatensis (D. Don) Oerst. ex D.P. Little) decline has been used as an example of how changing climate can impact a tree species. However, most previous research has not placed yellow-cedar decline within the context of yellow-cedar overall. We used a 2004–2013 regional inventory of the temperate rainforest of Alaska (671 plots with yellow-cedar) to estimate current attributes and a subset of 564 remeasured plots (established 1995–1998) to estimate recent change. Results show that in unmanaged forests, yellow-cedar live tree basal area recently (1995–1998 to 2004–2013) increased, with a 95% confidence interval of a 0.3% to 3.3% increase per decade. Yellow-cedar has a relatively low mortality rate, 0.41% of trees per year. An analysis of live tree to snag ratios was consistent with elevated mortality of yellow-cedar prior to 1995 but also indicated that little range contraction had occurred. The large numbers and wide geographic range of yellow-cedar trees in Alaska and the recent (1995–2013) stability in the monitored population serve as important contextual information for yellow-cedar decline. This research also illustrates that understanding the spatial and temporal complexities of how tree species respond to climate change will be improved if focused studies are accompanied by regional monitoring.

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Floristic Variation of Tree Communities and Their Association with Soil Properties in Pulau Jerejak, Penang, Peninsular Malaysia

Science Letters ◽

10.24191/sl.v14i1.7899 ◽

2020 ◽

Vol 14 (1) ◽

pp. 34

Author(s):

Faezah Pardi

Keyword(s):

Tree Species ◽

Diversity Index ◽

Basal Area ◽

Peninsular Malaysia ◽

Importance Value ◽

Conservation Action ◽

Endangered Tree ◽

Endangered Tree Species ◽

Tree Communities ◽

Floristic Variation

This study was conducted at Pulau Jerejak, Penang to determine the floristic variation of its tree communities. A 0.5-hectare study plot was established and divided into 11 subplots. A total of 587 trees with diameter at breast height (DBH) of 5 cm and above were measured, identified and recorded. The tree communities comprised of 84 species, 63 genera and 32 families. The Myrtaceae was the most speciose family with 10 recorded species while Syzgium glaucum (Myrtaceae) was the most frequent species. The Myrtaceae recorded the highest density of 306 individuals while Syzgium glaucum (Myrtaceae) had the highest species density of 182 individuals. Total tree basal area (BA) was 21.47 m2/ha and family with the highest BA was Myrtaceae with 5.81 m2/ha while at species level, Syzgium glaucum (Myrtaceae) was the species with the highest total BA in the plot with value of 4.95 m2/ha. The Shannon˗Weiner Diversity Index of tree communities showed a value of 3.60 (H'max = 4.43) and Evenness Index of 0.81 which indicates high uniformity of tree species. The Margalef Richness Index (R') revealed that the tree species richness was 13.02. Myrtaceae had the highest Importance Value of 20.4%. The Canonical Correspondence Analysis (CCA) showed that Diospyros buxifolia (Ebenaceae) and Pouteria malaccensis (Sapotaceae) were strongly correlated to low pH. Dysoxylum cauliflorum (Meliaceae) and Eriobotrya bengalensis (Rosaceae) were correlated to phosphorus (P) and calcium ion (Ca2+), respectively. Therefore, the trees species composition at Pulau Jerejak showed that the biodiversity is high and conservation action should be implemented to protect endangered tree species. Keywords: Floristic variation; Tree communities; Trees composition; Pulau Jerejak; Species diversity

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Contribution to the automation of the calculations involving the forest inventory with the aid of an office computer

Silva Gandavensis ◽

10.21825/sg.v20i0.1001 ◽

1970 ◽

Vol 20 ◽

Author(s):

R. Goossens

Keyword(s):

Tree Species ◽

Forest Inventory ◽

Basal Area ◽

Annual Increment ◽

Mixed Stands ◽

Mean Values ◽

Standing Trees ◽

General Program ◽

Magnetic Card ◽

The Right

Contribution to the automation of the calculations involving the forest inventory with the aid of an office computer - In this contribution an attempt was made to perform the calculations involving the forest inventory by means of an office computer Olivetti P203. The general program (flowchart 1), identical for all tree species except for the values of the different parameters, occupies the tracks A and B of a magnetic card used with this computer. For each tree species one magnetic card is required, while some supplementary cards are used for the subroutines. The first subroutine (flowchart 1) enables us to preserve temporarily the subtotals between two tree species (mixed stands) and so called special or stand cards (SC). After the last tree species the totals per ha are calculated and printed on the former, the average trees occuring on the line below. Appendix 1 gives an example of a similar form resulting from calculations involving a sampling in a mixed stand consisting of Oak (code 11), Red oak (code 12), Japanese larch (code 24) and Beech (code 13). On this form we find from the left to the right: the diameter class (m), the number of trees per ha, the basal area (m2/ha), the current annual increment of the basal area (m2/year/ha), current annual volume increment (m3/year/ha), the volume (m3/ha) and the money value of the standing trees (Bfr/ha). On the line before the last, the totals of the quantities mentioned above and of all the tree species together are to be found. The last line gives a survey of the average values dg, g, ig, ig, v and w. Besides this form each stand or plot has a so-called 'stand card SC' on wich the totals cited above as well as the area of the stand or the plot and its code are stored. Similar 'stand card' may replace in many cases completely the classical index cards; moreover they have the advantage that the data can be entered directly into the computer so that further calculations, classifications or tabling can be carried out by means of an appropriate program or subroutine. The subroutine 2 (flowchart 2) illustrates the use of similar cards for a series of stands or eventually a complete forest, the real values of the different quantities above are calculated and tabled (taking into account the area). At the same time the general totals and the general mean values per ha, as well as the average trees are calculated and printed. Appendix 2 represents a form resulting from such calculations by means of subroutine 2.

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Over half of western United States' most abundant tree species in decline

Nature Communications ◽

10.1038/s41467-020-20678-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hunter Stanke ◽

Andrew O. Finley ◽

Grant M. Domke ◽

Aaron S. Weed ◽

David W. MacFarlane

Keyword(s):

United States ◽

Tree Species ◽

Tree Mortality ◽

Temperate Forests ◽

Size Structure ◽

Forest Disturbance ◽

Population Decline ◽

Western United States ◽

Scale Transformation ◽

Forest Composition

AbstractChanging forest disturbance regimes and climate are driving accelerated tree mortality across temperate forests. However, it remains unknown if elevated mortality has induced decline of tree populations and the ecological, economic, and social benefits they provide. Here, we develop a standardized forest demographic index and use it to quantify trends in tree population dynamics over the last two decades in the western United States. The rate and pattern of change we observe across species and tree size-distributions is alarming and often undesirable. We observe significant population decline in a majority of species examined, show decline was particularly severe, albeit size-dependent, among subalpine tree species, and provide evidence of widespread shifts in the size-structure of montane forests. Our findings offer a stark warning of changing forest composition and structure across the western US, and suggest that sustained anthropogenic and natural stress will likely result in broad-scale transformation of temperate forests globally.

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Largest-Crown-Width Prediction Models for 53 Species in the Western United States

Western Journal of Applied Forestry ◽

10.1093/wjaf/19.4.245 ◽

2004 ◽

Vol 19 (4) ◽

pp. 245-251 ◽

Cited By ~ 28

Author(s):

William A. Bechtold

Keyword(s):

United States ◽

Prediction Models ◽

Basal Area ◽

Stem Diameter ◽

Western United States ◽

Quadratic Term ◽

Crown Width ◽

Coefficients Of Variation ◽

Bioclimatic Index ◽

Minor Improvement

Abstract The mean crown diameters of stand-grown trees 5.0-in. dbh and larger were modeled as a function of stem diameter, live-crown ratio, stand-level basal area, latitude, longitude, elevation, and Hopkins bioclimatic index for 53 tree species in the western United States. Stem diameter was statistically significant in all models, and a quadratic term for stem diameter was required for some species. Crown ratio and/or Hopkins index also improved the models for most species. A term for stand-level basal area was not generally needed but did yield some minor improvement for a few species. Coefficients of variation from the regression solutions ranged from 17 to 33%, and model R2 ranged from 0.15 to 0.85. Simpler models, based solely on stem diameter, are also presented. West. J. Appl. For. 19(4):245–251.

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Effects of nitrogen deposition on nitrate leaching from forests of the northeastern United States will change with tree species composition

Canadian Journal of Forest Research ◽

10.1139/cjfr-2016-0529 ◽

2017 ◽

Vol 47 (8) ◽

pp. 997-1009 ◽

Cited By ~ 5

Author(s):

Katherine F. Crowley ◽

Gary M. Lovett

Keyword(s):

United States ◽

Species Composition ◽

Nitrate Leaching ◽

Tree Species ◽

N Deposition ◽

Red Oak ◽

Northeastern United States ◽

Tree Species Composition ◽

White Ash ◽

Species Change

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.

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

10.15576/978-83-66602-20-5 ◽

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.

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Structure and Regeneration of Sal (Shorea robusta Gaertn. f.) Forests in Shiwalik Region of Kumaun Himalaya, India

Indian Journal of Forestry ◽

10.54207/bsmps1000-2017-0n83l0 ◽

2017 ◽

Vol 40 (1) ◽

pp. 1-8

Author(s):

Bhawna Adhikari ◽

◽

Bhawana Kapkoti ◽

Neelu Lodhiyal ◽

L.S. Lodhiyal ◽

...

Keyword(s):

Tree Species ◽

Basal Area ◽

Tree Canopy ◽

Canopy Density ◽

Kumaun Himalaya ◽

Shorea Robusta ◽

Canopy Trees ◽

Dense Forest ◽

Open Forest ◽

Sal Forest

Present study was carried out to assess the structure and regeneration of Sal forests in Shiwalik region of Kumaun Himalaya. Vegetation analysis and tree canopy density was determined by using quadrat and densitometer, respectively. Density of seedlings, saplings and trees was 490-14067, 37-1233, and 273-863 ind.ha-1 respectively. The basal area was 0.12-5.44 m2 ha-1 reported for saplings and 25.4-77.6 m2 ha-1 for trees. Regeneration of Sal was found good in Sal mixed dense forest followed by Sal open forest and Sal dense forest, respectively. Regeneration of Sal was assisted by the presence of associated tree species as well as the sufficient sunlight availability on ground due to adequate opening of canopy trees in Sal forest. Thus it is concluded that the density of tree canopy, sunlight availability and also associated tree species impacted the regeneration of Sal in the region.

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Tree Diversity and Their Regeneration in the Sacred Groves of Virajpet, Central Western Ghats, India

Notulae Scientia Biologicae ◽

10.15835/nsb839833 ◽

2016 ◽

Vol 8 (3) ◽

pp. 360-369

Author(s):

Devi A.G. PRASAD ◽

Shwetha BHARATHI

Keyword(s):

Tree Species ◽

Western Ghats ◽

Basal Area ◽

Sacred Groves ◽

Forest Patches ◽

Tree Species Composition ◽

Rich Diversity ◽

Central Western Ghats ◽

Undisturbed Forest ◽

The Rich

Sacred groves are one of the finest examples of informal way of conserving the forest wealth. Baseline data collection of their diversity, distribution and regeneration capacity becomes necessary for the management and conservation of these undisturbed forest patches. In this context, the present investigation was carried out using random quadrat method in the sacred groves of Virajpet, Karnataka, India. A total of 132 tree species belonging to 113 genera and 45 families were identified within five sacred groves. Higher basal area (51.73-85.65 m2/ha) and tree density (453.33-515.9 individuals/ha) were observed as compared to other forests of Western Ghats region. The present investigation has revealed a healthy regeneration of tree species. Seedling and sapling composition differed to some extent from the mature tree species composition which could be used in predicting the future possibilities. Protection and conservation of such sacred groves should be of interest, for better regeneration of the rich diversity they harbour.

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Forest Structure, Composition and Above Ground Biomass of Tree Community in Tropical Dry Forests of Eastern Ghats, India

Notulae Scientia Biologicae ◽

10.15835/nsb819746 ◽

2016 ◽

Vol 8 (1) ◽

pp. 125-133 ◽

Cited By ~ 8

Author(s):

Sudam Charan SAHU ◽

H.S. SURESH ◽

N.H. RAVINDRANATH

Keyword(s):

Forest Structure ◽

Tree Species ◽

Basal Area ◽

Eastern Ghats ◽

Tropical Dry Forests ◽

Above Ground Biomass ◽

Importance Value ◽

Shorea Robusta ◽

Ground Biomass ◽

C Stocks

The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB) of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters) were laid. The study showed the presence of 71 tree species belonging to 57 genera and 30 families. Dominant tree species was Shorea robusta with an importance value index (IVI) of 40.72, while Combretaceae had the highest family importance value (FIV) of 39.01. Mean stand density was 479 trees ha-1 and a basal area of 15.20 m2 ha-1. Shannon’s diversity index was 2.01 ± 0.22 and Simpson’s index was 0.85 ± 0.03. About 54% individuals were in the size between 10 and 20 cm DBH, indicating growing forests. Mean above ground biomass value was 98.87 ± 68.8 Mg ha-1. Some of the dominant species that contributed to above ground biomass were Shorea robusta (17.2%), Madhuca indica (7.9%), Mangifera indica (6.9%), Terminalia alata (6.9%) and Diospyros melanoxylon (4.4%), warranting extra efforts for their conservation. The results suggested that C-stocks of tropical dry forests can be enhanced by in-situ conserving the high C-density species and also by selecting these species for afforestation and stand improvement programs. Correlations were computed to understand the relationship between above ground biomass, diversity indices, density and basal area, which may be helpful for implementation of REDD+ (reduce emissions from deforestation and forest degradation, and foster conservation, sustainable management of forests and enhancement of forest carbon stocks) scheme.

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