scholarly journals Assessment of species diversity and distribution of woody species on selected plots in Olokemeji Forest Reserve, Ogun State, Nigeria

2021 ◽  
Vol 22 (3) ◽  
pp. 43-50
Author(s):  
D.M. Taiwo ◽  
S.I. Udoh ◽  
S.O. Olaoti-Laaro ◽  
O.R. Jeminiwa ◽  
M.S. Jeminiwa
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Woody Species ◽  
Tectona Grandis ◽  
Importance Value ◽  
Forest Reserve ◽  
Lowland Rain Forest ◽  
Ogun State ◽  
The Status ◽  
And Function

The Assessment of forest species composition and species diversity is essential in understanding the status of tree population and diversity for conservation purpose. Olokemeji forest reserve is situated in the lowland rain  forest of south-western Nigeria and it occupies a total land area of 58.88 km2 . Six study plots of 50m2 each were randomly selected and designated as Frequently Burnt Plot 1, Frequently Burnt Plot 2, Harvested Plot, Unharvested Unburnt Plot, Arable Plot 1 and Arable Plot 2 for the purpose of assessment of species diversity and distribution of woody species. Seven species of trees were identified belonging to five families. One hundred and eighty two stands were enumerated, with Unharvested Unburnt Plot having the highest number of trees at 50. The dominance index for the woody flora was 1 in Frequently Burnt Plot 1 and 2 as well as Arable Plot 1 and 2 except for the Harvested Plot that had the lowest (0.29) while the Unharvested Unburnt Plot had 0.75. Highest species richness was recorded at the Harvested Plot at 0.71. The species diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested Unburnt Plot (0.43). Evenness index was lowest in the Unharvested Unburnt Plot at 0.43. Tectona grandis had the highest relative importance value in the Frequently Burnt Plot 1. The low species richness and species diversity is a direct indication of anthropogenic interference in the study plots and the forest reserve; this requires urgent mitigation to prevent a total loss of its structure and function as expected of a forest reserve. Keywords: Species, Diversity, Evenness, Anthropogenic, Forest, Dynamics

scholarly journals Floristic Composition, Structure, and Species Associations of Dry Miombo Woodland in Tanzania

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Ezekiel Edward Mwakalukwa ◽  
Henrik Meilby ◽  
Thorsten Treue
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Forest Structure ◽  
Anthropogenic Activities ◽  
Good Condition ◽  
Floristic Composition ◽  
Woody Species ◽  
Present Species ◽  
Miombo Woodland ◽  
Forest Reserve

For the majority of forest reserves in Tanzania, biodiversity is poorly documented. This study was conducted to assess species richness (woody species), diversity, and forest structure and to examine relationships between species occurrence and topographic and edaphic factors in the Gangalamtumba Village Land Forest Reserve, a dry Miombo woodland area in Tanzania. A total of 35 nested circular plots with radii of 5, 15, and 20 m were used to collect data on woody species and soil samples across the 6,065 ha community-managed forest reserve. Stumps were measured 20 cm above ground. A total of 88 species belonging to 29 families were identified. Generally forest structure parameters and diversity indices indicated the forest to be in a good condition and have high species richness and diversity. Vegetation analysis revealed four communities of which two were dominated by the family Caesalpiniaceae, indicating large variation of site conditions and possible disturbances in the study area. The high level of diversity of woody species and the high basal area and volume indicate that the forest is in good condition, but the effect of anthropogenic activities is evident and stresses the need for proper management to maintain or enhance the present species diversity.

scholarly journals Contrasting the Effect of Forest Landscape Condition to the Resilience of Species Diversity in a Human Modified Landscape: Implications for the Conservation of Tree Species

Land ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 4 ◽  
Author(s):  
Mulugheta Ghebreslassie Araia ◽  
Paxie Wanangwa Chirwa ◽  
Eméline Sêssi Pélagie Assédé
Keyword(s):  
Land Use ◽  
Species Richness ◽  
Species Diversity ◽  
Conservation Strategy ◽  
Forest Landscape ◽  
Leading Change ◽  
Forest Reserve ◽  
Local Species Richness ◽  
Β Diversity ◽  
Local Species

Using landscape moderation insurance and Intermediate Disturbance Hypothesis (IDH) as frameworks, this study assessed the response of local assemblage among different land use regimes (mean β-diversity), using the Jaccard dissimilarity matrix in contrasting Human Modified Forest Landscapes (HMFLs). The study was conducted at the relatively simplified Mafhela Forest Reserve and the complex Thathe Vondo Forest Reserve in South Africa. The patterns of overall β-diversity between HMFL and State-protected Indigenous Forests (SIF) were compared and the leading change drivers were then untangled. This study found that human disturbance affects mean β-diversity of local assemblages among land use regimes between the two HMFLs in an ecologically contrasting manner. The HMFL in Mafhela Forest Reserve had distinct local assemblages among land use regimes and did not conform to the expectation of IDH. On average, HMFL had the same average local species richness as SIF, mainly due to change in species composition (species replacement) induced by land use disturbance. Land use intensity gradient was the leading change driver to explain the overall β-diversity of the Mafhela Forest Reserve. The findings in the Thathe Vondo Forest Reserve were in contrast with the Mafhela Forest Reserve. Although on average the HMFL had the same local species richness as SIFs, this was mainly due to a trade-off of species gain in trees along the rivers and streams and species loss in Culturally Protected Areas (sacred forests) (CPA) as expected by IDH. The contrasting findings imply that the effectiveness of any alternative conservation strategy is context-dependent. The resilience of local assemblages and conservation value of HMFL depends on the condition of the overall forest landscape complexity and cannnot be captured by one theory, nor by one species diversity matrix (e.g., β-diversity or Richness). It thus demands the application of complementary theoretical frameworks and multilevel modeling.

scholarly journals Woody species diversity from proposed ecologically sensitive area of northern Western Ghats: implications for biodiversity management

2020 ◽  
Vol 12 (9) ◽  
pp. 16048-16063
Author(s):  
M. Tadwalkar ◽  
A. Joglekar ◽  
Monali Mhaskar ◽  
A. Patwardhan
Keyword(s):  
Species Diversity ◽  
Tropical Forests ◽  
Western Ghats ◽  
Stand Structure ◽  
Woody Species ◽  
Importance Value ◽  
Threatened Plant Species ◽  
Western Ghats Of India ◽  
Woody Species Diversity ◽  
The Western Ghats

The Western Ghats of India support an array of tropical forests ranging from wet evergreen to scrub formations.  Several endemic and threatened plant species are located in areas other than protected areas (PAs).  There is an urgent need to understand species diversity in areas other than PAs, for effective management of tropical forests.  In this context, reserve forests and informal PAs of Amboli from northern Western Ghats have been investigated. Woody species composition, diversity, and stand structure were assessed by laying quadrats and transects (n=46, area=2.575ha) in closed and open canopy forest patches covering habitat heterogeneity and environmental gradient of the area. A total of 2,224 individuals (of 87 species, 68 genera, and 35 families) was enumerated.  Memecylon umbellatum, Syzygium cumini, and Diospyros nigrescens were found to be the most dominant species as per importance value index.  Melastomataceae was the most dominant family as per family importance value, whereas Euphorbiaceae and Rutaceae were the most speciose.  Fourteen IUCN Red List assessed species and 18 species endemic to the Western Ghats were encountered.  Endemic species accounted for nearly 20% of the total number of individuals sampled.  Demographic profile exhibited reverse ‘J’ pattern.  Average basal area was 27.02m2 per hectare. Woody species diversity of Amboli forests was found comparable with other PAs from northern Western Ghats.  Amboli and the adjoining area have been proposed as ecologically sensitive and in the wake of anthropogenic and developmental pressures they experience, it calls for urgent conservation attention.

scholarly journals Composition and importance value of tree-families in undisturbed and disturbed moist tropical forest of eastern Nepal

2017 ◽  
Vol 7 (1) ◽  
pp. 41-46
Author(s):  
Tilak Prasad Gautam ◽  
Tej Narayan Mandal
Keyword(s):  
Ecosystem Services ◽  
Species Diversity ◽  
Tropical Forest ◽  
Tree Species ◽  
Tree Species Diversity ◽  
Forest Disturbances ◽  
Forest Stands ◽  
Importance Value ◽  
The Status ◽  
Family Importance Value

Tropical forest disturbances have reduced the tree species diversity and hereby, the ecosystem services provided by them. Present study was carried out to understand the status of tree-families in terms of their dominance in the undisturbed and disturbed stands of moist tropical forest in eastern Nepal. As per the result, the dominant family in both the forest was Dipterocarpaceae, with family importance value of 53.6 and 53.9 in undisturbed and disturbed stands, respectively. The second dominant family in both forest stands was Rubiaceae.

Regeneration Success and Plant Species Diversity of Allegheny Hardwood Stands After Roundup Application and Shelterwood Cutting

1994 ◽  
Vol 11 (4) ◽  
pp. 109-116 ◽  
Author(s):  
Stephen B. Horsley
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Plant Species ◽  
Negative Impact ◽  
Woody Species ◽  
Diversity Indices ◽  
Species Group ◽  
Plant Species Diversity ◽  
Herbaceous Species ◽  
Species Groups

Abstract The presence of desirable regeneration and plant species diversity was studied in five Allegheny hardwood stands before and for 7 yr after application of Roundup herbicide and shelterwood cutting to remove interfering understories of hayscented and New York fern, striped maple, and beech and to establish desirable hardwood regeneration. In each of five 20 ac stands, 10 ac were sprayed with 1 lb ai (active ingredient)/ac of Roundup in August 1979; the remaining 10 ac were unsprayed. The entire 20 ac stand received a shelterwood seed cut the following winter. On treated plots, fern was reduced from 57% stocking before treatment to 7% 1 yr after treatment; striped maple and beech stocking was reduced by 16% during the same time. By the fourth year after treatment, regeneration stocking of desirable hardwood species had doubled on treated plots but remained unchanged on untreated control plots. Species diversity was measured by species richness, three diversity indices--Berger-Parker, Margalef and Shannon, and index-free diversity ordering. Neither the herbicide treatment nor the shelterwood seed cut had a statistically significant effect on species richness of either woody species or herbaceous species groups. Nor was there a significant effect of treatments on woody species diversity as measured by the three diversity indices. Index-free diversity ordering showed. (1) a trend toward increase in less common species on Roundup-treated areas, and (2) the diversity of herbaceous species groups was higher in all 7 yr after treatment with Roundup. Values of the three diversity indices were higher for herbaceous species on Roundup-treated subplots for 2 to 7 yr after treatment. Much of this increase resulted from germination of seed bank grasses, sedges, and Rubus spp. With the qualification that long-term and current browsing by deer has impoverished the flora of the Allegheny hardwood forest, diminishing potential treatment effects, the study demonstrated that Roundup treatment aided desirable regeneration establishment, did not have a negative impact on woody species or herbaceous species group diversity, and may have increased diversity of herbaceous species. North. J. Appl. For. 11(4): 109-116.

Potential role of sacred groves in biodiversity conservation in Tanzania

2003 ◽  
Vol 30 (3) ◽  
pp. 259-265 ◽  
Author(s):  
F.H. Mgumia ◽  
G. Oba
Keyword(s):  
Species Richness ◽  
Similarity Index ◽  
Woody Species ◽  
Taxonomic Diversity ◽  
Sacred Groves ◽  
Managed Forest ◽  
Forest Reserve ◽  
Community Based Conservation ◽  
The Government

Sacred groves, some as old as several centuries, may have contributed to the preservation of some plant species in Tanzania. This has led conservationists to consider whether sacred groves could be used for in situ conservation. Eight sacred groves of the Ugunda chieftaincy of the Wanyamwezi in central Tanzania representing burial sites that varied from 6–300 years old were inventoried to compare woody species richness and taxonomic diversity with those of forest plots in a state managed Forest Reserve. Although they occupied a relatively small area the sacred groves had greater woody species richness and taxonomic diversity than the state managed Forest Reserve. The forest plots and the groves shared a species similarity index of 45%, suggesting that the sacred groves contributed to in situ conservation of the miombo woodland biodiversity. Some of the woody species were absent in the forest plots, also suggesting that groves served as a refuge for some species. An inventory of all existing sacred groves could provide important information on their role in in situ conservation. In order to promote them for community-based conservation of biodiversity the government should declare sacred groves as preservation sites, and incorporate them into modern conservation systems.

scholarly journals Floristic Structure of Fire Experimental Plots of Olokemeji Forest Reserve, Ogun State, Nigeria

2020 ◽  
Vol 24 (11) ◽  
pp. 1861-1865
Author(s):  
DM Taiwo ◽  
OR Olatidoye ◽  
OR Jeminiwa ◽  
TO Oyebola ◽  
C Omonu
Keyword(s):  
Tree Species ◽  
Basal Area ◽  
Relative Importance ◽  
Importance Value ◽  
Forest Reserve ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Ogun State ◽  
Mean Diameter ◽  
Floristic Structure

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

scholarly journals State of a Lowland Tropical Forest in South-West Nigeria

2019 ◽  
Vol 8 (2) ◽  
Author(s):  
L.D. Wakawa ◽  
F.N. Ogana ◽  
T.E. Adeniy
Keyword(s):  
Species Diversity ◽  
Management Practices ◽  
Diversity Index ◽  
Basal Area ◽  
Line Transect ◽  
Forest Reserve ◽  
Lowland Tropical Forest ◽  
The Status ◽  
Fragmented Forests ◽  
Original Species

Forests play a significant role in human existence and survival. Timely and reliable information on the status of a forest is essential for assessing the extent of regeneration and degradation. However, when such information is lacking effective forest management practices becomes impossible. Therefore, this study assessed the tree species diversity, richness and structure of Oluwa forest reserve with the view of ascertaining it present state which is crucial for management and conservation purposes. To achieved these, a systematic line transect was used in the laying of eight (8) temporary sample plots (TSPs) of size 50m x 50m. Trees with Dbh≥10cm in the selected plots were enumerated, identified and measured. The results indicate that 535 individual trees were enumerated cutting across 26 families and 58 species. The reserve has the Margalef's index of species richness, Shannon-Weiner diversity Index (H') and Pielou's Species Evenness Index (EH) of 9.07, 3.43 and 0.84 respectively. The forest has a mean Dbh (cm), mean height (m), total basal area/ha (m2) and total volume/ha (m3) of 24.7, 16.9, 36.63 and 602.09 respectively. Majority of trees were found in the smaller diameter and height classes; giving rise to reverse J-shaped structure. The structure of Oluwa forest reserve has been altered significantly while the species diversity and richness seems to indicate a sign of improvement compared to previous studies. With proper management, the remaining fragmented forests could regenerate and replenish to save some of the original species composition of the reserve.

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