A structural analysis of rain forest at Korup and Douala–Edea, Cameroon

1996 ◽  
Vol 104 ◽  
pp. 177-224 ◽  
Author(s):  
D. McC. Newbery ◽  
J. S. Gartlan
Keyword(s):  
Spatial Distribution ◽  
Tree Species ◽  
Rain Forest ◽  
National Park ◽  
Individual Species ◽  
Forest Reserve ◽  
Frequency Distributions ◽  
Relative Lack ◽  
Large Size ◽  
Group 5

SynopsisDiameter frequency distributions (dfds) of 197 tree species in Korup National Park and 118 tree species in Douala–Edea Forest Reserve (based onc.41 000 and 25 000 trees ≥ 30 cm gbh in 135 and 104 plots along four transects at each site, respectively) were individually classified into four groups of species according to their maximum diameters (≥99% trees <50, <70 and <90cm dbh, and > 1% ≥90cm dbh), and separated into two abundance classes (n≥50 andn= 20–49 (or 15–49). A fifth group, from those species in 3 and 4, was defined by a relative lack of small stems and given detailed attention. Dfds were evaluated for all species together on a transect and site basis, and compared for individual species across transects, and between sites for those group 5 species in common.Analysis focussed on three large ectomycorrhizal species in groups 3 and 4,Microberlinia bisulcata, Tetraberlinia bifoliolataandT. moreliana(Caesalpiniaceae), which were restricted to, and dominated, the forest on the nutrient-poor soils of transect P at Korup.M. bisulcata, the most abundant, was markedly group 5 in character, with very few small trees, whilst theTetraberliniaspecies had strong replacement potential. Although there were 27 species (42% of groups 3 & 4) at Korup and 19 (48%) at Douala–Edea in group 5,M. bisulcatawas unique in its combination of large size, dfd, mycorrhizal habit, spatial distribution and soil association. The potential replacement of this species was contrasted also with a non-ectomycorrhizal caesalp with similar dfd that occurred on nutrient-richer soils,Erythrophleum ivorense.Knowledge of the Caesalpiniaceae-richla forêt biafriéeneof Letouzey (which includes Korup and Douala–Edea) is reviewed, and the distribution, ecology and regeneration of the caesalps discussed. Structure and inferred dynamics of the forest at Korup are discussed with special regard to the ectomycorrhizal species.

scholarly journals Ash Yellows in Zion National Park: Impact, Identity of Pathogen, Mode of Spread, and Prospects for Management

1991 ◽  
Vol 15 ◽  
pp. 283-291
Author(s):  
Wayne Sinclair ◽  
Michael Treshow ◽  
Robert Davis
Keyword(s):  
Tree Species ◽  
National Park ◽  
Zion National Park ◽  
Large Size ◽  
Fraxinus Velutina ◽  
Mycoplasmalike Organisms

Velvet ash (Fraxinus velutina) in Zion Canyon have declined in vigor, and some are dying. This species is aesthetically and ecologically important in the canyon, because it is one of only three tree species that commonly grow to large size on the canyon floor. Ash yellows (AshY), a disease caused by unnamed mycoplasmalike organisms (MLOs), is common in velvet ash in Zion Canyon and is suspected to contribute to the decline of this species. This project deals with the ecology and epidemiology of ash yellows and possibilities for managing it in Zion National Park (ZNP).

scholarly journals Spatial Distribution and Interspecific Associations of Tree Species in a Tropical Seasonal Rain Forest of China

PLoS ONE ◽  
2012 ◽  
Vol 7 (9) ◽  
pp. e46074 ◽  
Author(s):  
Guoyu Lan ◽  
Stephan Getzin ◽  
Thorsten Wiegand ◽  
Yuehua Hu ◽  
Guishui Xie ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Tree Species ◽  
Rain Forest ◽  
Interspecific Associations ◽  
Tropical Seasonal Rain Forest

scholarly journals The structure of Leguminosae-Detarioideae dominant rain forest in Korup National Park, Cameroon

2021 ◽  
Vol 154 (3) ◽  
pp. 376-390
Author(s):  
Xander M. Van der Burgt ◽  
David M. Newbery ◽  
Sylvanos Njibili
Keyword(s):  
Tree Species ◽  
Rain Forest ◽  
National Park ◽  
Size Structure ◽  
Single Species ◽  
Permanent Plots ◽  
Tree Species Composition ◽  
Lowland Rain Forest ◽  
Korup National Park ◽  
Southwest Region

Background and aims – We studied a cluster of trees in the Leguminosae subfamily Detarioideae, to: (1) determine the size, structure, and tree species composition of this cluster; (2) map the size, shape, and structure of groups of individual Detarioideae tree species in the cluster.Location – Lowland rain forest in southern Korup National Park, in the Southwest Region of Cameroon.Material and methods – Trees in permanent plots were recorded using standard plot enumeration techniques. Outside plots, single-species tree groups were recorded by a rapid technique. From this data, detailed maps of groups of trees were prepared.Key results – Detarioideae tree species occur co-dominant in a cluster of at least 32 km2 with an irregular shape. The cluster contained at least 42 Detarioideae tree species; at least 29 of these occurred in groups ranging in size from 50 to 4000 m across, depending on the species. Groups usually had circular shapes, caused by ballistic seed dispersal. In a group, trees were always mixed with trees of several other Detarioideae species. Every area within the cluster contained a specific set of Detarioideae species. The percentage of Detarioideae trees ≥ 60 cm stem diameter on 50 ha was up to 76% in Detarioideae-rich forest, to 6% in Detarioideae-poor forest. Of all trees in the centre of the cluster, 2.8% belonged to pioneer forest species, which indicates that disturbance levels were low during the past generations of trees.Discussion – The forests in the Detarioideae cluster have not been subject to substantial human and natural impacts in historic or prehistoric times. Such forests are exceptional in Africa. Detarioideae clusters may indicate glacial age forest refuges, especially clusters that contain both many different Detarioideae species and some Detarioideae species endemic to the cluster.

scholarly journals POPULATION STRUCTURE OF Araucaria angustifolia IN THE IGUAÇU NATIONAL PARK

FLORESTA ◽  
2015 ◽  
Vol 45 (2) ◽  
pp. 361 ◽  
Author(s):  
Alci Albiero Junior ◽  
Lívia Godinho Temponi ◽  
Franklin Galvão ◽  
Paulo Cesar Botosso ◽  
Ana Tereza Bittencourt Guimarães
Keyword(s):  
Population Structure ◽  
Spatial Distribution ◽  
Rain Forest ◽  
National Park ◽  
Forest Edge ◽  
Araucaria Angustifolia ◽  
Aggregate Distribution ◽  
Temperate Rain Forest ◽  
Males And Females ◽  
Number Of Individuals

AbstractThe aim of this study was to analyze the population structure, regeneration and spatial distribution of Araucaria angustifolia (Bertol.) Kuntz. within a natural forest and in forest edge with agricultural monoculture. All araucaria individuals from 10 cm high were recorded in 200 plots of 10 x 10 m. 479 individuals were sampled (416 at the edge and 63 inside). Of these, 33 were females, 37 males, 49 juveniles and 360 regenerating individuals. The population structure performance was similar to standard inverted-J. Regenerating individuals had mainly the aggregate distribution pattern, while juveniles, males and females had a uniform pattern. Density of the canopy affected frequency of the individuals, where higher frequencies at higher densities were observed, indicating that regeneration of this species is more effective in shadowed environments. Due to the large number of individuals sampled in different size classes, the Iguaçu National Park is an important conservation remaining of A. angustifolia.Keyword: Density canopy; mixed temperate rain forest; spatial distribution; regeneration.  ResumoEstrutura populacional de Araucaria angustifolia no Parque Nacional do Iguaçu. O objetivo do presente trabalho foi analisar a estrutura populacional, regeneração e distribuição espacial de Araucaria angustifolia (Bertol.) Kuntz no interior de uma floresta natural e na borda de uma floresta com monocultura agrícola. Todos os indivíduos de araucária a partir de 10 cm de altura foram registrados em 200 parcelas de 10 x 10 m, sendo amostrados 479 indivíduos (416 na borda e 63 no interior). Desses, 33 eram fêmeas, 37 machos, 49 juvenis e 360 regenerantes. A estrutura da população apresentou padrão semelhante ao J-invertido. Os indivíduos regenerantes apresentaram principalmente o padrão agregado de distribuição, já para os juvenis, machos e fêmeas o padrão foi uniforme. A densidade do dossel influenciou a frequência de indivíduos, sendo observadas maiores frequências em maiores densidades, indicando que a regeneração da espécie é mais efetiva em ambientes sombreados. Devido ao grande número de indivíduos amostrados em diferentes classes de tamanho, o Parque Nacional do Iguaçu representa um importante remanescente na conservação de A. angustifolia.Palavras-chave: Densidade do dossel; Floresta Ombrófila Mista; distribuição espacial; regeneração.

scholarly journals Photosynthetic Rates of Four Tree Species in the Upper Canopy of a Tropical Rain Forest at the Pasoh Forest Reserve in Peninsular Malaysia.

Tropics ◽  
2001 ◽  
Vol 10 (4) ◽  
pp. 519-527 ◽  
Author(s):  
Akio FURUKAWA ◽  
Takeshi TOMA ◽  
Yutaka MARUYAMA ◽  
Yosuke MATSUMOTO ◽  
Akira UEMURA ◽  
...  
Keyword(s):  
Tree Species ◽  
Rain Forest ◽  
Tropical Rain Forest ◽  
Peninsular Malaysia ◽  
Forest Reserve ◽  
Photosynthetic Rates ◽  
Pasoh Forest Reserve

scholarly journals Natural regeneration in logging gaps of different sizes in Subri River Forest Reserve (Ghana)

2022 ◽  
Author(s):  
Maame Esi Hammond ◽  
Radek Pokorný ◽  
Simon Abugre ◽  
Augustine Gyedu
Keyword(s):  
Tree Species ◽  
Natural Regeneration ◽  
Conservation Status ◽  
Selective Logging ◽  
Medium Size ◽  
Similar Species ◽  
Timber Species ◽  
Forest Reserve ◽  
Strict Adherence ◽  
Large Size

AbstractSubri River Forest Reserve (SR) is the most extensive forest area in Ghana with an accompanying rich floral species. Over the years, logging from both legally prescribed and illegal operations remain the predominant forest disturbance in SR. Gap creation following logging is crucial in determining tree species composition and diversity. Hence, the study evaluated the composition and diversity of naturally regenerated tree species in logging gaps of different sizes and, again examined the roles of these tree species in fulfilling the economic and ecological agenda of sustainable forest management after logging in SR. Twelve gaps were randomly selected: 4 each were grouped into small size (≤ 200 m2), medium size (201–300 m2), and large size (≥ 300 m2). Data were gathered from 1 m2 circular area at gap centres and repeatedly inside 1 m width strip along 20 m individual N-S-E-W transects. Species diversity differed significantly between gap sizes. Higher diversity indices were measured in large size gaps. Gap sizes shared similar species. There were significant differences among various height groupings of tree species across all three gap sizes. Pioneers preferred medium to large size gaps, while shade-tolerant tree species preferred small size gaps for their abundance. Vulnerable and Lower Risk Near Threatened tree species under Conservation Status and, Premium and Commercial tree species under Utilisation Status preferred small size gaps for their proliferation and conservation. Therefore, we recommend the single tree-based selective logging for ensuring creations of small to medium size (200–300 m2) gaps through adjustments to the logging permit process, revision of Allocation Quota Permit, strict adherence to the 40-year polycyclic selection system, along with more dedicated enforcement and monitoring. Changes along these protocols would tremendously facilitate natural regeneration of different suites of timber species resulting in the improvement of the overall biodiversity conservation associated with the forest, more sustainable forest harvests and more income to those who receive permits.

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