Multiple Stable Dominance States in the Congo Basin Forests

Understanding the dynamics of dominant tree species in tropical forests is important both for biodiversity and carbon-related issues. We focus on the Congo Basin (East of Kisangani) to investigate the respective roles of topographic/soil gradients and endogenous dynamics in shaping local variations in dominance. We used a dataset of 30 1-ha plots, in which all trees above 10 cm diameter at breast height (DBH) were censused. Soil samples were analyzed for standard pedologic variables and a digital elevation model permitted to infer topography and hydromorphy. We found that this forest is characterized by variations in the abundance of three dominant species: Petersianthus macrocarpus (P.Beauv.) Liben (PM), Gilbertiodendron dewevrei (De Wild.) J.Leonard (GD) and Julbernardia seretii (De Wild.) Troupin (JS). These variations occur independently of substratum or topography variations. At plot level, the local relative abundance never reached 50%, the threshold for monodominance proposed in the literature, but rather progressively increased to reach higher values for canopy trees (>60 cm DBH), where this threshold could be exceeded. We found no sign of shifting compositional dynamics, whereby the dominant species would switch between the canopy and the undergrowth. Our results, therefore, support the possibility of the existence of stable dominance states, induced by endogenous processes, such as biological positive feedbacks fostering monodominance. We also document a strong relation between monodominance level and alpha diversity, when giving more weight to abundant species which is expected (R² = 0.79) but also when giving more weight to rare species (R² = 0.37), showing that monodominance influences tree species richness patterns. Structural differences existed between groups, with the PM group having more (and on average smaller) stems and lighter wood on average, but paradoxically also higher biomass and basal area.

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Gap-phase regeneration in selectively logged lowland swamp forest, northeastern Costa Rica

Journal of Tropical Ecology ◽

10.1017/s0266467498000194 ◽

1998 ◽

Vol 14 (2) ◽

pp. 247-260 ◽

Cited By ~ 16

Author(s):

EDWARD L. WEBB

Keyword(s):

Costa Rica ◽

Tree Species ◽

Structural Damage ◽

Basal Area ◽

Abundant Species ◽

Selective Logging ◽

Stem Density ◽

Swamp Forest ◽

Gap Phase ◽

Multiple Tree

For sustainable logging to be achieved in tropical forests, there must be successful gap-phase regeneration to restock the logged-over area. This study examined three aspects of gap-phase regeneration in selectively logged lowland swamp forest of northeast Costa Rica. First, logging gaps were censused immediately after extraction to determine the density of advanced regeneration. Stem density and basal area of residual trees ≥ 10 cm dbh in logging gaps was >85% lower than undisturbed forest, and all trees in gaps had sustained structural damage. The common canopy species Pentaclethra macroloba (Fabaceae) was the most abundant species in gaps whereas the timber tree Carapa nicaraguensis (Meliaceae) was absent from all censused gaps. This suggests that canopy replacement, particularly by Carapa, will depend on trees <10 cm dbh or by seed input into logging gaps. Second, the diversity of the understorey was compared with 6-y old single-tree and multiple-tree logging gaps. Multiple-tree logging gaps were the most diverse, but dominated by two ruderal species; however many shade-tolerant species were present in those gaps. This indicates that controlled selective logging can result in a localized shift in species composition, but that logging gaps should return to pre-logging composition with time under a carefully implemented, controlled harvesting regime. Finally, this study found a significant effect of a fringing Carapa tree on logging gap seedling density. Thus, seed arrival into gaps is a barrier to logging gap regeneration, particularly for a large-seeded tree species. Gap-phase regeneration by a large-seeded tree species in managed forest would benefit from seed broadcasting into gaps.

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Edge-Interior Disparities in Tree Species and Structural Composition of the Kilengwe Forest in Morogoro Region, Tanzania

ISRN Biodiversity ◽

10.1155/2014/873174 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

David Sylvester Kacholi

Keyword(s):

Species Richness ◽

Tree Species ◽

Anthropogenic Activities ◽

Basal Area ◽

Abundant Species ◽

Forest Edge ◽

Structural Composition ◽

Forest Interior ◽

Contrasting Habitats ◽

Brachystegia Spiciformis

A survey to determine the variation in species and structural composition of trees along the edge-interior gradient was done in the Kilengwe forest in Morogoro region, Tanzania. The forest was categorized into three habitats, namely, edge (0–100 m), intermediate (100–200 m), and interior (>200 m) depending on the distance from the forest margin. A total of six plots of 0.04 ha each were randomly placed in each of the habitats whereby all trees with DBH ≥ 10 cm were inventoried. A total of 67 species representing 26 families were recorded. Fabaceae was the most speciose and abundant family. Brachystegia spiciformis was the most abundant species. Of the recorded species, 10.45% were common in the three habitats while 8.95%, 13.43%, and 26.86% occurred exclusively to the edge, intermediate, and interior habitats, respectively. The forest interior was significantly rich in terms of species richness, diversity, density, and basal area than the edge and intermediate habitats. The edge had significantly higher number of stumps/ha. In summary, the results suggest that edge/intermediate and interior are contrasting habitats in terms of tree species richness, diversity, and structural composition. Moreover, the forest edge and intermediate habitats were found to be characterized by high anthropogenic activities compared to the forest interior habitat.

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Tree Species Composition and Distribution Pattern in a Myristica Swamp of Northern Kerala, India

Current World Environment ◽

10.12944/cwe.11.3.08 ◽

2016 ◽

Vol 11 (3) ◽

pp. 743-750

Author(s):

K. A Sreejith ◽

U. M Chandrashekara ◽

T. K Nirmesh ◽

V. B Sreekumar

Keyword(s):

Species Composition ◽

Distribution Pattern ◽

Tree Species ◽

Dominant Species ◽

Basal Area ◽

Essential Elements ◽

Tree Species Composition ◽

The Family ◽

Species Composition And Distribution ◽

Species Specific

Knema Phytosociological studies have been carried out in a Myristica swamp in Northern Kerala to reveal the composition and distribution pattern of different tree species. On the basis of IVI, the family Myristicaceae was dominant and the association is attenuata - Myristica malabarica -Holigarna arnottiana type. The species like Gymnacranthera canarica and Myristica fatua var. magnifica, which are believed to be the essential elements of Myristica swamps, are totally absent here. A total 403 individuals (gbh > 10.1 cm) were recorded with a basal area of 34.25 m2 ha-1 in 0.5 ha. area. Total number of species recorded was 28, which represent 21families in which Myristicaceae represents 48.18% of total IVI. Among two dominant species, Myristica malabarica prefer swampy area hence their number of individual shows decreasing trend when we move from the swamp while the second dominant species Knema attenuata showing a reverse trend and was completely absent in the first five quadrats where soil water content is too high. Species specific eco-physiological studies are required to understand the reasons for change in the distribution pattern of these dominant species.

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Effect of local topographic heterogeneity on tree species assembly in an Acacia-dominated African savanna

Journal of Tropical Ecology ◽

10.1017/s0266467419000014 ◽

2019 ◽

Vol 35 (2) ◽

pp. 46-56 ◽

Cited By ~ 2

Author(s):

Paul Musili Mutuku ◽

David Kenfack

Keyword(s):

Species Diversity ◽

Tree Species ◽

Stand Structure ◽

Basal Area ◽

Abundant Species ◽

Habitat Associations ◽

Tree Species Diversity ◽

Knee Height ◽

Local Species ◽

Topographic Heterogeneity

AbstractStand structure and tree species diversity patterns were examined plot-wide and among four topographically defined habitats (plateau, cliff, low plain and depressions) in a 120-ha permanent plot in an Acacia-dominated savanna in Mpala Ranch, central Kenya. The four habitats were defined by clustering the 3000 quadrats of 20 × 20 m in the plot based on their altitude, slope and convexity. Structural and floristic differences among the four habitats were examined and species-habitat associations were tested for the 30 most abundant species using torus translation randomization tests. The plot included 113 337 trees in 62 species with diameter at knee height ≥ 2 cm (18.4 species ha−1), 41 genera and 23 families. Fabaceae with the genus Acacia were the dominant family, followed by Euphorbiaceae and Ebenaceae. Tree density and basal area were twice as high on low plain and depressions than on the plateau. Species richness was highest in the cliff and was seven times higher than in the adjacent plateau. Half of the species assessed showed significant positive associations with one habitat and 21 showed significant negative associations with at least one habitat. The variation in stand structure and tree species diversity within the Mpala plot shows that topography is among the important drivers of local species distribution and hence the maintenance of tree diversity in savannas.

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Sinecological analysis of the montane rain forrest of Omiltemi, Guerrero

Botanical Sciences ◽

10.17129/botsci.1404 ◽

2017 ◽

pp. 31

Author(s):

Jorge Meave ◽

Miguel Angel Soto ◽

Luz María Calvo-Irabien ◽

Horacio Paz-Hernández ◽

Susana Valencia-Avalos

Keyword(s):

Forest Structure ◽

Tree Species ◽

Basal Area ◽

Floristic Composition ◽

Abundant Species ◽

Structural Features ◽

Tropical Species ◽

Mountain Forest ◽

Eastern United States ◽

Important Species

The floristic composition, structure, and texture of 1 ha of mesophytic mountain forest in Omiltemi, Guerrero, is described. With 138 species of vascular plants in the plot, this forest is very rich, with epiphytes, trees and herbs comprising the most diverse growth forms. The geographic affinities of this forest are diverse; many elements are shared with the andean-mesoamerican regions, and others are present in the deciduous forests of eastern United States. The Omiltemi forest is similar to other communities from western Mexico, and many of the endemic elements of this region occur in Omiltemi. This forest is structurally dense, approximately 24 m high, without a well-defined stratification. The canopy is made up mainly by Carpinus caroliniana and Quercus uxoris; Pinus ayacahuite is an emergent tree. The understory is rich in small-statured tree species. The horizontal distributions of the trees were analyzed, and only two understory species had a clumped pattern. Density is 2,096 trees/ha, total basal area is 49.82 m2/ha and cover is 263.8% The most important! species in the forest structure are those reaching the canopy. Two trends in the diametric structures of tree species populations were found: 1) with classes of small sizes having high frequencies, and gradually decreasing towards classes of larger sizes, and 2) with classes of intermediate sizes having lower frequencies than classes of smaller and larger sizes. The internal spatial variation of the forest structure was analyzed using multivariate methods. Tropical species were usually found in more humid places, while species of temperate affinities occurred in more exposed sites. Five floristic groups were recognized, and their associated structural features are described. This forest bears leaves throughout the year, although some of the most abundant species of the canopy are deciduous. The textural characteristics of pollination, dispersal and tree architecture are described. In addition, the mixed character of the mesophytic mountain forest of Omiltemi is discussed and related to its marginal geographic location.

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Stem Decay in Live Trees: Heartwood Hollows and Termites in Five Timber Species in Eastern Amazonia

Forests ◽

10.3390/f11101087 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1087

Author(s):

Ana Alice Eleuterio ◽

Maria Aparecida de Jesus ◽

Francis E. Putz

Keyword(s):

Tree Species ◽

Logistic Model ◽

Basal Area ◽

Abundant Species ◽

Timber Species ◽

Hollow Trees ◽

Large Trees ◽

Timber Tree ◽

Species Characteristics ◽

Components Analysis

Research Highlights: Tree size and wood characteristics influenced the susceptibility of five Amazonian timber tree species to heartwood decay and colonization by termites. Termites occurred in the heartwoods of 43% of the trees, with Coptotermes testaceus the most abundant species. Background and Objectives: Hollows and rotten cores in the stems of living trees have ecological and economic impacts in forests managed for timber. The decision on whether to cut or maintain hollow trees in such forests must account for the susceptibility of different tree species to decay. We investigated tree and wood characteristics of living trees of five commercial timber species in the eastern Amazon that influenced the likelihood of heartwood decay and the occurrence of termite nests inside the rotten cores. Materials and Methods: We used Pearson’s correlations and one-way analysis of variance (ANOVA) to explore relationships among tree basal area and hollow area. We used principal components analysis (PCA) to analyze the variation of wood anatomical traits, followed by a linear regression to explore the relationships between PCA scores, and heartwood hollow area. We used a logistic model to investigate if the probability the occurrence of colonies of C. testaceus inside tree cores varied with tree and species characteristics. Results: Heartwood hollow areas increased with stem basal area. Larger hollows were more likely to occur in species with higher vessel and ray densities, and smaller diameter vessels. Termites occurred in the hollows of 43% of the trees sampled, with C. testaceus the most common (76%). The probability of encountering termite nests of C. testaceus varied among tree species and was positively related to wood density. Conclusions: This study shows that given the increased likelihood of stem hollows and rotten cores in large trees, tree selection criteria in managed tropical forests should include maximum cutting sizes that vary with the susceptibility of different tree species to stem decay.

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Hyperdominance in Amazonian forest carbon cycling

Nature Communications ◽

10.1038/ncomms7857 ◽

2015 ◽

Vol 6 (1) ◽

Cited By ~ 123

Author(s):

Sophie Fauset ◽

Michelle O. Johnson ◽

Manuel Gloor ◽

Timothy R. Baker ◽

Abel Monteagudo M. ◽

...

Keyword(s):

Carbon Cycling ◽

Tree Species ◽

Dominant Species ◽

Maximum Size ◽

Abundant Species ◽

Data Set ◽

Forest Function ◽

Amazonian Forests ◽

Global Carbon ◽

Amazonian Trees

Abstract While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region.

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

Forest Service Research Data Archive ◽

10.2737/rds-2013-0013 ◽

2013 ◽

Cited By ~ 4

Author(s):

Barry T. Wilson ◽

Andrew J. Lister ◽

Rachel I. Riemann ◽

Douglas M. Griffith

Keyword(s):

United States ◽

Tree Species ◽

Basal Area ◽

Live Tree

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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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