scholarly journals Composition of tree species in Onigambari Forest Reserve, Oyo State, Nigeria

2020 ◽  
Vol 24 (10) ◽  
pp. 1815-1819
Author(s):  
N.O. Haastrup ◽  
I Agboje ◽  
M.O. Lawal ◽  
B.O. Fadimu ◽  
O.A. Sangotoyinbo ◽  
...  

The tree composition of Onigambari Forest Reserve in Oyo State was evaluated by laying out a plot size of 50 x 50 m2 resulting to four plots per hectare. 104 and 93 stems per hectare were recorded. A total of 197 tree stands were encountered in the two compartments studied with family Sterculiaceae with species Cola gigantean, Cola millenii, Sterculia africana, Sterculia oblonga, Sterculia tragacantha, Triplochiton scleroxylon, Pterogota macrocarpa and Nesogordonia papaverifera.as the most abundant having 34 stands, followed by the family Papilionoideae with species Baphia nitida with 20 stands as the most abundance species. About thirty-nine percent of the tree species encountered were wildlings having a diameter at breast height of ≤ 10 cm. Less than one percent (0.50%) of the trees were of merchantable size. This could be a thing of concern and it calls for adequate resourceful and sustainable management techniques. Habits in Onigambari Forest Reserve are presented in Table 1. A total of forty-three (43) species of trees distributed into twenty (20) families were encountered. Family Sterculiaceae and Fabaceae was the richest with eight (8) species each followed by family Euphobiaceae with (5) tree species. Based on their habit, these species were classified into 100% trees. Furthermore, it is of the importance that the forest reserves be protected from illegal/indiscriminate logging among other anthropogenic activities in order to allow it regenerate. Keywords: Abundance, merchantable, sustainable, resourceful

2013 ◽  
Vol 6 (3) ◽  
pp. 196-204

Associations between bivariate variables relative to the unexplained relationships of height-Dbh (diameter at breast height) models were investigated. Seven permanent sample plots measuring 40m by 250m at Omo Forest Reserve were used to assess the relationships between height and diameter at breast height of three tree species as affected by the variables of neighbouring trees. The result showed differences in the coefficient of determination of the bivariate models and multivariate models. The models arrived at for each of the species and for the bivariate models are: Scottelia coriaceae: Ht = 2.59 + 0.473D+ 0.0012D2 for 5cm ≤ D ≤100cm (R2 = 0.70) Sterculia rhinopetala: Ht = 5.96 + 0.467D+ 0.00296D2 for 5cm ≤ D ≤100cm (R2 = 0.77) Strombosia pustulata: Ht = 2.02 + 0.722D+ 0.00581D2 for 5cm ≤ D ≤ 60cm (R2 = 0.81) Where both Ht and D are height and Diameter at breast height. While on the other hand the multivariate models that considered the effect of neighbouring trees are: Scottelia coriaceae: 2 1 2 3 4 Ht = 3.74 + 0.41x −1.14x + 0.205x +1.278x (R = 0.723) Sterculia rhnopetala: 2 1 2 3 4 Ht = 6.18 + 0.2601x +1.163x + 0.438x − 0.442x (R = 0.608) Strombosia pustalata: 2 1 2 3 4 Ht = 6.84 + 0.399x − 0.318x − 0.138x − 0.838x (R = 0.650) x1 = diameter at breast height, x2 = Mean neighbouring tree distance, x3 = Frequency of the neighbouring tree and x4 = Position of the crown.


2021 ◽  
Vol 25 (5) ◽  
pp. 829-834
Author(s):  
S.O. Olaoti-Laaro ◽  
D.M. Taiwo ◽  
K.A. Adeniji ◽  
S.A. Odewo ◽  
Z.T. Animashaun ◽  
...  

Anthropogenic activities has caused depletion of majority of Nigeria forest reserves, reducing forest lands to agricultural lands and grasslands. These prompted this study to consider the diversity of species as well as their species composition in the forest in February 2021. Four sub-plots were established in a cluster with an area of 50m by 50m, with 20m distance between each plots and 10m as edge effect. Twenty five tree species belonging to fifteen families were found in the study site. Family Malvaceae was the most represented. Triplochiton scleroxylon recorded the highest relative importance value (11.23). The diversity indices across the study plots assessed were species richness, evenness, Shannon index and dominance. Dominance indices across the study plots were low, asides for Plot 4 where. Triplochiton scleroxylon was dominant. Simpson index was highest in Plot 1 and lowest at Plot 4. Shannon index was highest, though in moderation in Plot 1 and relatively low in the remaining plots. Evenness indices across the four plots were high. However, the summarized diversity indices for the study site reflected dominance was generally low, Simpson index was high, Shannon index was moderate and Evenness index was moderate. The dendrogram depicted the relationship among the tree species population based on similarities and dissimilarities. Triplochiton scleroxylon belonged to a cluster while every other species with close similarity were categorized under cluster 2.


Author(s):  
Franklin Bantar Nworo ◽  
Njoh Roland Ndah ◽  
Egbe Enow Andrew

Tropical montane forests are considered to be one of the most species diverse ecosystems. These areas pose specific edaphic and environmental characteristics which enable these areas to harbour wide varieties of organisms. Some of these organisms are threatened and others are endemic to the area. The quest for food and other resources has resulted to indiscriminate exploitation of these montane forest. This study aimed to investigate the stand structure, distribution patterns and regeneration status of six tree species (Nuxia congesta, Pittosporum mannii, Podocarpu slatifolius, Prunus africana, Schefflera abyssinica and Syzygium guineense) along altitudinal gradients in the Kilum-Ijim Forest Reserve, Cameroon. A total of six study plots of one hectare (100 x100 m) each were laid across a 120 m elevation gradient. Two plots were established at each altitudinal gradient with elevations 2377 m, 2437 m and 2497 m. Measurements were taken for tree height, diameter at breast height (DBH 1.3 m) for the tree and poles. The digital Vernier callipers were used to measure collar diameters of seedlings and saplings. The highest tree density of 385 stems/ha was recorded for N. congesta at altitude 2497 m while the least was 20 stems/ha for S. abyssinica at altitude 2377m. The highest seedling density was 1563 stems/ha recorded for P. mannii at altitude 2377m and the least was noted for S. abyssinica at all the three altitudinal gradients.  Nuxia congesta had the highest basal area of 8809.23m2/ha at altitude 2437 m and the least of 74.82m2/ha for P. latifolius at altitude 2437 m.  The highest IVI occurred in N. congesta (131.91) was recorded at altitude 2377 m and the least (24.91) occurred in P. latifolius at altitude 2437 m. The spatial distributions of studied tree species were generally clumped and irregular. The regenerations of species were generally poor, though fair regenerations were noticed for N. congesta and P. mannii. The results showed that the six tree species were highly disturbed by anthropogenic activities. It is therefore imperative to develop and implement effective conservation measures to sustain the biodiversity of this reserve.


2020 ◽  
Vol 24 (11) ◽  
pp. 1861-1865
Author(s):  
DM Taiwo ◽  
OR Olatidoye ◽  
OR Jeminiwa ◽  
TO Oyebola ◽  
C Omonu

Total enumeration of tree species was carried out fire experimental plot of Olokemeji forest reserve for relative importance value (RIV) mean heights, mean diameter at breast height and mean basal area. Three investigative plot (Plot A, B and C) were established. Plot A which represents Early Burn is burnt annually during the dry season while Plot B was burnt annually during the rainy season when the trees are still wet and Plot C serves as the protected area. Gmelina arborea had the highest relative importance value (28.31), this is followed by Dalbergia sissoo which had RIV of 10.94. Plot C recorded the highest frequency of trees with the highest tree heights, this is closely followed by Plot A and Plot B being the plot with the lowest mean height. Plot C has the highest mean diameter at breast height (DBH) of trees and it is followed by Plot B and Plot A with very close mean DBH. The highest mean basal area was also recorded in Plot C, the highest total basal area and tree volume was also recorded at Plot C as 32.2 m2 ha-1 and 188.8 m3. The size distribution of tree species depicts that Plot C has been protected just as expected Keywords: Forest, Structure, Flora, Dynamics, Fire


Author(s):  
Iyanuoluwa Kikelomo Ajayi ◽  
Joshua Kayode ◽  
Benson Oluwafemi i Ademiluy

An inventory of tree biodiversity was carried in Ekiti State University, Ado-Ekiti, Nigeria, which is an institution where ecological and economic roles of trees are disseminated. The study involved the use of a stratified sampling technique to carry out a survey of trees species in the University. The campus was divided into four strata - Road side (A), Car parks (B), Office area (C), Student halls/ religion area (D) - and each stratum was further sub-divided into sub-strata. All the trees within each sub-stratum were identified to species level with their scientific, local and family names and they were counted and recorded. The relative frequency, relative density and relative abundance of the identified species were determined. Similarities indices and indices of diversity were determined on the tree species sampled among the strata. The results obtained revealed that a total of 27 tree species, belonging to 17 families were sampled in the campus. The family Caesalpiniaceae has the highest number of species. Some of the identified tree species were found in multiple and dual strata while some occurred in only one stratum. A total of 838 tree individuals were obtained. The most frequently occurring species were T. grandis, G. arborea and P. longifolia with 298, 181 and 149 individuals respectively. The indices of similarities among the strata were low. However Strata A and B as well as A and C appeared to be similar in tree composition. Strategies that would improve and maintain tree composition in the University campus were proposed


Check List ◽  
2009 ◽  
Vol 5 (3) ◽  
pp. 542 ◽  
Author(s):  
Lingassamy Arul Pragasan ◽  
Narayanaswamy Parthasarathy

We provide a list of tree species enumerated from a total of 60 ha area sampled in the tropical forests of southern Eastern Ghats, Tamil Nadu, India. A total of 272 tree species (Ā 30 cm girth at breast height) representing 181 genera and 62 families were recorded. Euphorbiaceae with 25 species was the most speciose family, followed by Moraceae (17 species), Rubiaceae (17), Rutaceae (14) and Lauraceae (12). At the generic level, Ficus dominated with 12 species, followed by Diospyros (9), Acacia (6), Terminalia (6) and Grewia (5). Anthropogenic activities such as hill cultivation, construction of dams, roads, buildings, etc. affect the already fragmented southern Eastern Ghats, and underline the need for effective conservation measures. 


2019 ◽  
Vol 30 (6) ◽  
pp. 242-245
Author(s):  
Hamadttu A. F. El-Shafie

Four insect species were reported as new potential pests of date palm in recent years. They are sorghum chafer (Pachnoda interrupta), the rose chafer (Potosia opaca), the sericine chafer beetle (Maladera insanablis), and the South American palm borer (Pysandisia archon). The first three species belong to the order Coleoptera and the family Scarabaeidae, while the fourth species is a lepidopteran of the family Castniidae. The injury as well as the economic damage caused by the four species on date palm need to be quantified. Due to climate change and anthropogenic activities, the date palm pest complex is expected to change in the future. To the author's knowledge, this article provides the first report of sorghum chafer as a pest damaging date palm fruit.


1990 ◽  
Vol 4 (4) ◽  
pp. 405-416 ◽  
Author(s):  
MIGUEL PINEDO-VASQUEZ ◽  
DANIEL ZARIN ◽  
PETER JIPP ◽  
JOMBER CHOTA-INUMA

2015 ◽  
Vol 39 (6) ◽  
pp. 985-994 ◽  
Author(s):  
Markus Gastauer ◽  
Marcos Eduardo Guerra Sobral ◽  
João Augusto Alves Meira-Neto

According to its owners, the Forest of Seu Nico (FSN) from the Viçosa municipality, Minas Gerais, Brazil, never has been logged and is therefore considered a primary forest. Nevertheless, the forest patch suffered impacts due to selective wood and non-timber extraction, fragmentation and isolation. Aim of this study was to test if the FSN, despite impacts, preserved characteristics of primary forests, which are elevated percentages of non-pioneer (>90%), animal-dispersed (>80 %), understory (>50%) and endemic species (~40%). For that, all trees with diameter at breast height equal or major than 3.2 cm within a plot of 100 x 100 m were identified. With 218 tree species found within this hectare, the FSN's species richness is outstanding for the region. The percentages of non-pioneer (92 %), animal-dispersed (85 %), understory (55 %) and endemic species (39.2 %) from the FSN fulfill the criteria proposed for primary forest. Therefore, we conclude that the FSN maintained its characteristics as a primary forest which highlights its importance for the conservation of biotic resources in the region, where similar fragments are lacking or not described yet.


2014 ◽  
pp. 121-126
Author(s):  
H. Häggman ◽  
S. Sutela ◽  
J. Edesi ◽  
J. Krajňáková ◽  
A. Bertolini ◽  
...  

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