Ecological and Structural Analyses of Trees in an Evergreen Lowland Congo Basin Forest

Abstract

Floristic inventory and diversity assessments are necessary to understand the present diversity status and conservation of forest biodiversity. Studying the variation height-diameter woody provides insight into the general characteristics of the trees diversity pattern. This study mainly focuses on aimed to assess the effectiveness of trees diversity and structure in two study sites. The study was conducted at Ipendja evergreen lowland moist forest in northern Republic of Congo. The sampling design was systematic consisted of parallel transect 1 or 2 km part, and divided into consecutive rectangular plots, each 5000m 2 (25 x 200 m, i.e. 0.5 ha). Within eight plots censuses, all trees with a DBH ≥ 10 cm were identified and measured. A total of 1340 trees has been recorded belonged 145 species and 36 families (n = 607 and n = 733, respectively in Mokelimwaekili and Sombo sites). The results show that the leading botanical families were Sapotaceae follows by Euphorbiaceae, Meliaceae, Caesalpiniaceae, Sterculiaceae, Annonaceae and Rubiaceae. The most representative species were C. mildbraedii, S. kamerunensis and P. oliveri, i.e. 62.06%, 30.34% and 28.27% respectively, demonstrated that they were the leading dominant species of this forest ecosystem. Shannon index were 4.29 bits for Mokelimwaekili and 4.22 bits for Sombo. While Pielou's evenness index was between 0.88 and 0.90, respectively for the Mokelimwaekili and Sombo sites. The similarity coefficient for Jaccard was 62% and 58% for Sorensen. There are highlight variations in tree diversity indices across sites and plots in Ipendja forest.

Assessing the Effectiveness of Protected Areas on Floristic Diversity in Tropical Forests

“…5-7), to evaluate floristic diversity and accuracy indices (Spellerberg and Fedor, 2003;CBD, 2006;Fedor and Spellerberg, 2013). Using Sorensen's similarity index (Spellerberg and Fedor, 2003;Folega et al, 2011;Ekoungoulou et al, 2017), to perform the basal area and specific richness study for the Lesio-louna forest.…”

“…3). From the circular plot center to the first circle (small circle), the radius was 0-6 m or 12 m of diameter and tree inventory [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] (medium circle), the radius was 0-14 m or 28 m of diameter, with tree inventory 30-60 cm DBH (Fig. 3).…”

“…Tropical forest ecosystems apart from being carbon sinks are known to harbour over 50% of terrestrial http://www.aloki.hu • comparative study of populations because it is independent of the size of the studied population (Chen and Li, 2011;Folega et al, 2014). Species richness is a measure of the variety of species in a sampled area (Ekoungoulou et al, 2017). It is often a representation based simply on a count of the number of species in a particular sample (Fedor and Spellerberg, 2013;Fayolle et al, 2014b).…”

Tree Biomass Estimation in Central African Forests Using Allometric Models

“…A double decameter has been used to measure the DBH (diameter at breast height) for each tree (only trees with DBH ≥ 10 cm were measured) in all eight plots of study area. We excluded trees with DBH < 10 cm [6] because such trees hold a small fraction of aboveground biomass in forest woodland, and would otherwise dominate the signal in regression models [18] [29] [37]. Wood specific gravity for each tree has been provided by Global Wood Density Database from DRYAD (Retrieved January 13, 2016 at https://doi.org/10.5061/dryad.234).…”

“…Wood density (ρ) was extracted from a global wood density database (http://datadryad.org/handle/10255/dryad.235: Retrieved January 13, 2016; [39] [40]). Wood density (ρ) is an important predictive variable in all regressions model to estimate trees biomass [6]. The pantropical allometric model proposed by [18] has been fitted to log-transformed data using ordinary least-squares regression:…”