Tanzania Journal Of Forestry And Nature Conservation

 Journal

 Foliar Morphological And Anatomic Characteristics In Entandrophragma Species In South West Nigeria.

 Lawal A. And Akinnusi D.

 2020

In Nigeria, identification of Entandrophragma species in their natural range has been very difficult as the same species in different environments exhibit different morphological features. This research was designed to assess foliar morphological and anatomic characteristics in already known and clearly tagged Entandrophragma species at the International Institute of Tropical Agriculture (IITA) Ibadan, Oyo State with a view to providing some diagnostic features that could help resolve current taxonomic uncertainties in their wild counterpart. In this study, three tagged trees of E. cylindricum, E utili and E. angolensis were located and their leaves were collected for morphological and anatomic study. All quantitative data obtained were analyzed. E. angolense and E. cylindricum could be grouped by 30° obliqueness, E. utile is delineated from other two taxa by the possession of 75° obliqueness. On the adaxial surfaces of the three species, epidermal cells were straight undulating or wavy. The periclinal walls in E. angolense were glabrous, slightly coarse in E. utile while it was striated in E. cylindricum. This could be used in these species identification. Also, crystal sand on the adaxial surface of E. angolense is was a spot character for the species. 

 Nigerian Society For Conservation Biology

 Conference

 Distribution, Species Diversity And Conservation Potentials Of Sacred Groves In Southwestern, Nigeria.

 Onyekwelu J.C., Tolorunju M.S., Agbelade A.D., Lawal A., Stimm B. And Mosandl R.

 2020

NAN 

 Commonwealth Forestry Association, Nigeria Chapter

 Conference

 Contemporary Status Of Some Selected Forests In Ondo State, Nigeria.

 Obadun F.M., Adekunle V.A.J And Lawal A

 2020

NAN 

 Not Sci Biol.

 Journal

 Phytotherapy And Polycyclic Logging: Implication On Genetic Multiplicity And Diversity Of African Mahogany In Tropical Rainforest

 LAWAL1, Victor A.J. ADEKUNLE, Oghenekome U. ONOKPISE

 2019

There are over 8,000 globally threatened tree species. For each species, there is a different story behind why they are threatened and what values we stand to lose if we do not find the means to save them. Mahogany, a member of Meliaceae, is a small genus with six species. Its straight, fine and even grain, consistency in density and hardness makes it a high valued wood for construction purposes. The bitter bark is widely used in traditional medicine in Africa. The high demand for bark has also led to the total stripping of some trees, complete felling of larger trees to get the bark from the entire length of the tree and bark removal from juvenile trees. These species are now threatened with extinction due to selective and polycyclic logging, and also excessive bark removal. The natural regeneration of mahogany is poor, and mahogany shoot borer Hypsipyla robusta (Moore) attacks prevent the success of plantations within the native area in West Africa. In developing countries, most of the Khaya species exists in the wild state; therefore, the regeneration and long-term conservation are at the mercy of the vagaries of nature and the profit driven herb collectors and timber merchants. It becomes urgently necessary by government of developing countries to place ban on further harvesting of mahogany species to allow the remaining few trees of mahogany in the forest to recuperate and produce substantial seeds for regeneration. 

 Journal Of Forestry Research And Management.

 Journal

 Eco-Physiological Variation And Adaptation Mechanisms Of Azadirachta Indica A. Juss In Nigeria.

 Lawal A., Ademujimi B.P. And Oladoyinbo B. M.

 2019

This study assessed diverse foliar morphological and anatomical characteristics exhibited by Azadirachta indica towards adapting to various climatic conditions in Nigeria. The study covered three ecological zones of Nigeria, namely: Rainforest (Akure), Derived Savanna (Ekiti) and Guinea Savanna (Ilorin). In each ecological zone, ten trees at not less than 50 meters apart were randomly selected and ten leaf samples were collected from each of the selected trees. The number of leaflets on each leaf was counted. Out of the ten leaf samples, two leaves were randomly selected and all their leaflets were measured using Leaf Area Meter. Variables measured include: Leaflet Surface Area (LSA), Leaflet Length (LL), Leaflet Width (LW), Apex Length (AL) and Degree of Obliqueness (DO). Leaflets were also subjected to further analyses, including: estimation of stomata density, epidermal cell density on both adaxial and abaxial surfaces and cuticle thickness. It was revealed that there were significant reductions in all the foliar morphological variables from rainforest to derived savanna and guinea savanna ecological zones, respectively. The mean densities recorded for stomata and epidermal cells varied across the ecological zones, likewise, the cuticle thickness. Highest stomata density and cuticle thickness was recorded in this species occurring in lowland rainforest (33.33) and guinea savanna (28.16?m) respectively. Whereas, very Low stomata density was observed in this species occurring in derived savanna (25.00). High stomata density in the leaflets of this species found in the rainforest may be a mechanism developed to adjust to the low light intensity in this ecological zone to aid photosynthesis. High cuticle thickness observed in Guinea savanna may be associated with control of water loss as a result of high temperature. More so, low stomata density in the derived savanna may also be associated with less water availability and high need to conserve water by controlling evapo-transpiration from the surface of the leaflets. This study has added more knowledge to ecophysiological variation and adaptation mechanism of Azadirachta indica. 

 Tropical Conservation Science

 Journal

 Towards Conservation Of Genetic Variation Of Tropical Tree Species With Differing Successional Status: The Case Of Mansonia Altissima A. Chev And Triplochiton Scleroxylon K. Schum

 Akin Akinnagbe, Oliver Gailing, Reiner Finkeldey, And Amadu Lawal

 2019

Two important West African timber tree species with differing successional status, Mansonia altissima A. Chev and Triplochiton scleroxylon K. Schum were investigated in this study. Triplochiton scleroxylon is a pioneer species found in open forests, whereas Mansonia altissima is a nonpioneer light-demanding tree species occurring in closed forests. Amplified fragment length polymorphism markers were used to compare the genetic diversities of these two timber species in stands with different degrees of human impact (isolated forest patch, logged forest, farmland, plantation, and primary forest). Contrasting effects of human impact on genetic diversity were detected for these two timber species. The results suggested severe effects of human impact on the genetic diversity of Mansonia altissima, a nonpioneer species. However, no adverse effect was recorded in Triplochiton scleroxylon, a pioneer species. These findings indicate that nonpioneer tree species could be more prone to genetic erosion than pioneer tree species as a result of adverse human impacts. Therefore, conservation of genetic diversity in both pioneer and nonpioneer tree species populations would likely necessitate different measures. 

 Taiwania

 Journal

 Tree Species Diversity And Regeneration Potential Of Soil Seed Bank In Akure Forest Reserve, Ondo State, Nigeria

 Bernard OMOMOH, Victor ADEKUNLE, Amadu LAWAL, Olarewaju AKINBI

 2019

The relationship of soil seed bank and above vegetation of secondary forest of Akure forest reserve investigated in this study. This was carried out by assessing the seedling emergence of soil seed bank taken from the secondary forest. In the aboveground vegetation, all sapling below 10 cm (DBH 10 cm) within 50 m by 50 m plot size were also identified and diameter at breast height were measured. Data were collected from seeds emergence of soil seed bank and above vegetation, in strict nature reserve, four-five (45) woody species (40 trees and 5 shrubs) were encountered, a total of 5 families distributed into 7 species and 7 genera in sapling while seedling emergence were observed at different depths of soil seed bank; at 0-3 cm depth (1 fern, 1 climber and 7 herbs), 3-6 cm depth (5 herbs, 1 woody species, 1 climber, 1 fern), 6-9 cm depth (5 herbs, 1 tree and 1 ferns. The soil seed bank could thus play an important role in knowing the status of regeneration potential of this strict nature reserve forest. However, the high dominant species in the soil seed bank suggest that where such forest is disturbs the likely plants species to pioneer the succession and restorations are these herbaceous species encountered. 

 Forests And Forest Products Society

 Journal

 Volume Yield And Carbon Hoard In Two Community-managed Forests Of Ekiti State, Southwest, Nigeria.

 Agbelade A.D. And Lawal A.

 2019

This study aimed at evaluating the potential of community-managed forests to sequestration carbon. Systematic line transect was employed in the laying of the plots. Atotal of 8 sample plots in each community-based forest were used and soil samples were taken from four soil depths for soil carbon determination. Non-destructive method was used in the estimation of volume, above-ground biomass, below-ground biomass and carbon stock. The result also revealed significant difference in tree volume, biomass and carbon stock between the two forests. Tree Biomass and carbon stock were significantly higher in Ogun Onire community forest (48173.07 kg/ha, 30.02 T/ha) than in the community herbal heritage forest (10.745.31 kg/ha, 6.07 T/ha). Soil organic carbon estimated for Ogun Onire community forest (126.59 Tg) was significantly higher than that of community herbal heritage forest (67.95 Tg). Higher tree volume, biomass and carbon stock obtained for Ogun Onire community forest could be traced to the stiffer conservation measure put in place by the community as compared to the community herbal heritage forest where traces of encroachment and cultivation of arable crops were found. For sustainable availability of forest resources in community herbal heritage forest, severe conservation measure is recommended. 

 FUTA, AGRIC

 Conference

 Haplotype Diversity In The Populations Of Khaya Species In South West Nigeria

 Lawal A., Adekunle V.A.J., Onokpise O.U. And Akinbi O. J.

 2019

NAN 

 Applied Tropical Agriculture

 Journal

 Assessment Of The Genetic Variation In Chrysophyllum Albidum G. Don Using CP SSR Marker.

 Boboye, O. M., Lawal, A. And Oyerinde, O. V.

 2018

Chrysophyllum albidum is among the forest tree species that provides Non-Timber Forest Products (NTFPs) of enormous domestic significant to both rural and urban dwellers in West Africa, with great export potentials. The fruit pulp is widely consumed and thus play a significant role in food security. C. albidum, which is classified among the endangered tree species with a high probability of going into extinction in the nearest future, is endowed with a high degree of climatic adaptability. This indicate that there may exist a tremendous genetic variation that needs to be identified for immediate conservation. In this study, total genomic DNA was extracted from 0.020 g powder of silica gel dried leaves using the QIAGEN DNeasy plant Mini Kit according to the manufacturer’s instruction. DNA was amplified by Polymerase Chain Reaction (PCR). The estimation of total gene diversity (Ht), gene diversity due to variation within population (Hs), gene diversity due to differences among populations (Gst) and gene flow (Nm*) were 0.1330±0.041, 0.0472±0.002, 0.645, and 0.275 in that order. This reveals that genetic base of this important tree species has been seriously eroded. Therefore, urgent steps must be taken by individual, organizations and government to conserve the genetic base of this important tree species.