Browsing by Author "Olubode, O.S."

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Allelopathic effect of pentaclethra macrophylla benth. leaf extracts on germination and seedling growth of maize and okra
(2020) Ogbu, J.U.; Awodoyin, R.O.; Olubode, O.S.
Pentaclethra macrophylla Benth. is an indigenous leguminous tree of southern Nigeria's agroecosystems, whose seeds are used as spices; however, its allelopathy potential is not understood. Therefore, this study was aimed at investigating P. macrophylla allelopathic effects on germination and seedling growth of maize and okra. Materials and Methods: Allelopathic effects of Aqueous Leaf Extracts (ALE) of P. macrophylla at 0 (control), 10, 20, 40 and 80% concentrations on maize (n = 200) and okra (n = 200) seed germination and seedling growth were assessed in laboratory and screen house nursery. Total germination (%) for both crops was determined at one Week After Sowing (WAS); while Number of Leaves (NL), Plant Height(PH) (cm), Root Length (RL) (cm) and Dry Weight (DW) (g) were evaluated at 8 WAS. Experimental design used in the study was completely randomized design. Data were analyzed using descriptive statistics and ANOVA at a0.05. Results: Above 90.0% germination was recorded for maize in all the ALE concentrations, while for okra ALE-10 gave significantly highest germination (90.0±8.7%) and ALE-80 gave least (42.5±26.3%). Maize and okra seedlings given ALE-40 had highest NL, PH and DW;* while ALE-0 (control) had least values in PH and DW, respectively. Control had highest RL in both crops. The ALE-10 gave least RL in maize and ALE-20 gave least RL in okra. Conclusion: Pentaclethra macrophylla aqueous leaf extract at 10% enhanced germination, while 40% concentration encouraged dry matter accumulation and height in maize and okra seedlings.
Allelopathic effects of aqueous extracts of olax subscorpioidea oliv. on seed germination and growth of okra (abelmoschus esculentus (l.) moench) in Ibadan, Nigeria
(2022) Ayoola, D.O.; Olubode, O.S.
Allelochemicals are being explored as environmentally friendly options in weed management and crop yield improvement as opposed to use of synthetic pesticides which have serious environmental damages. Allelopathic effects of aqueous extracts of different parts of Olax subscorpioidea on Okra seed germination in Petri-dish bioassays and okra performance in pot experiment were conducted in the Department of Crop Protection and Environmental Biology, University of Ibadan using a complete randomized design (CRD) and with treatments replicated five times. Ten okra seeds in three replicates were treated in separate petri-dishes with 2 ml water extracts of stem, leaf, fruit, bark and root of Olax subscorpioidea, and 2 ml distilled water (control) in two trials. Pot trials was carried out using okra seedlings with treated with 100 ml extracts at seven days intervals. Data were collected on number of germinated seeds daily and lengths of five randomly selected plumules and radicles at 7 days after sowing (DAS). Number of leaves, plant height, root and shoot dry weight of seedlings were also measured using standard methods. Data were analyzed by analysis of variance. Statistically significant (P<0.05) means were separated using Duncan’s Multiple Range Test. Leaf extract had the highest concentrations of phenolic, flavonoid and saponin compounds compared, while the stem extract had the least metabolite concentrations. Leaf extracts exerted highest inhibition on okra germination at 2 and 7 DAS in the first trial and at 7 DAS in the second trial compared to the bark, stem, root and fruit extracts of Olax subscorpioidea. The seedling growth and yield parameters in treatment extracts were better than control. In conclusion, Olax subscorpioidea has allelopathic potential with effects on germination and seedling growth of okra. It can be used as an alternative bioherbicide. Its production and agricultural potentials should be promoted.
Assessment of bitter yam (dioscorea dumentorum [kunth] pax) production in Oyo state, Nigeria
(2023) Olubode, O.S.; Fasola, I.A.; Gbadamosi, I.T.
Production of bitter yam (Discoreae dumentorum [Kunth.] Pax) is low in Oyo State, Nigeria. Two varieties are mainly cultivated, but there is limited information on factors responsible for low production and varietal preferences among farmers. This study investigated the demography, farming practices and differential proximate compositions as probable causes of low production of bitter yam in Oyo State. One hundred and twenty (120) copies of structured questionnaire were administered to selected respondents. Multistage sampling was used in selecting respondents in Oyo state from local government areas constituting four agricultural zones and 12 villages to collect demographic, production-related information, and constraints to production. Data were analyzed using descriptive statistics as well as analysis of variance (ANOVA). The result revealed that although bitter yam cultivation in Oyo state was male dominated (70%), majority of the farmers were old (57%), married (72%) and poorly educated (55%). Its production was for subsistence, and it was mainly grown in intercrop with other yam species. Ranked production constraints indicated poor marketability as the most extremely severe constraint, followed by labour unavailability and storage inadequacies. White bitter yam variety with superior basic proximate composition than Yellow Yam was preferred for cultivation. Subsistence production of bitter yam in Oyo state could be up-scaled through government intervention via farmer-centered education and public awareness and provision of infrastructure to facilitate cultivation, transportation, and storage.
Assessment of soil seed banks in relation to aboveground vegetation in three ecosystems within university of ibadan, Ibadan, South Western Nigeria
(2020) Afolabi, A.S.; Egberongbe, R.K.; Awodoyin, R.O.; Olubode, O.S.
Succession after disturbance. In the assessment of natural re-vegetation capacity of some ecosystems within the University of Ibadan, Nigeria, SSB contents were assessed and compared with the above-ground vegetation (AGV). Three ecosystems (Arable, Fallow and Plantation) were selected, with 25 x 25 m area marked out in each for random sampling, using XY-ordinate technique. Ten points were located for placement of wooden quadrat (50 x 50 cm). All plant species that rooted within each quadrat were enumerated. Soil samples were collected at 0-15 cm depth at the centre of each quadrat and bulked by site. One kilogram soil, replicated 12 times in each site, was monitored for seedling emergence for five months. Species richness (R), Shannon-Wiener index (H') and Jaccard Similarity Index (J) were determined for AGV and SSB. Plant family Poaceae dominated AGV while Amaranthaceae dominated SSB in all ecosystems. The R in AGV and SSB ranged from 14-24 and 6-15 respectively. The H' in AGV were close (2.27-2.69) but ranged from 0.84 (plantation) to 2.27 (arable) in SSB. The J for SSB/AGV were 33.3%, 14.3% and 5.9% in arable, fallow and plantation ecosystem respectively, indicating the highest species resemblance in the most disturbed arable ecosystem.
Assessment of soil seedbank composition, woody species composition and structure in olokemeji forest reserve, ogun state, nigeria.
(2017) Taiwo, D.M.; Olubode, O.S.; Oyelowo, O. J.
Olokemeji forest reserve has undergone tremendous changes through anthropogenic impact on the forest ecosystem, such human impacts include farming activities, logging of wood and burning. The soil seed bank composition, woody species composition and structure were studied with a view to determine the restoration potential of the forest reserve. Six sample plots (Frequently burnt plot 1, Frequently burnt plot 2, Harvested plot, Unharvested Unburnt plot, Arable plot 1 and Arable plot 2) designated as FT1, FT2, HP, UP, AP1 and AP2 were randomly selected. Floral species identification, relative importance value (RIV), species diversity and multivariate analysis all followed standard procedures. Three replicate soil samples were collected at two different depths (0-15 cm and 15-30 cm) from each plot and they were subjected to seedling emergence for five months to determine the species composition, density and diversity of the seed banks of the six study plots. The results of seedling emergence showed that soil collected at 0-15 cm depth had a higher RIV, species diversity, individual, abundance and dominance index than soil collected at 15-30 cm depth. However, the evenness index for seedlings in the soil seed bank was considerably high across the two soil depths which depicted equal measure of spread within each study plots at both soil depths. Tectona grandis was highest in RIV. 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. The diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested unburnt Plot (0.43). Trees in Unharvested unburnt Plot had the highest mean diameters at breast height, basal areas and mean heights, while the Arable Plots had lowest mean diameters at breast height, mean basal areas and mean heights.
Attributes and ecological potentials of dumpsite flora in the peri-urban area of Ibadan, Nigeria
(2023) Olubode, O.S.; Ibrahim, B.A.
Dumpsites are spaces used disposal of urban and peri-urban wastes. Their public health concern has not made them to be adequately explored for positive potentials in Nigeria. This study investigated the the floristic structure and comparative potential of a dumpsite with arable farms for conservation and phytoremediation. The study was conducted at a 10-hectare peri-urban Lapite dumpsite (N 07o34.121ʹ, E 003o54.857ʹ) in Ibadan, Oyo State, Nigeria; and three arable farmlands (Control) located 200 m-300 m away from Dumpsite. Stratified sampling was conducted using 414 quadrats (each 1m2) in five strata of dumpsite, and a systematic sampling of flora of farms with 263 quaddrats in 21 transects laid 5 m apart. Data were collected on species composition, abundance,density and frequency of occurence. They were subjected to analysis of Relative importance value (RIV), density, and multivariate analysis. Species with phytoremediation potentials were identified. Ninety one species of herbaceous flora in 33 families and 99 species in 38 families were enumerated on the dumpsite and farmlands respectively. Solanum nigrum L., Tridax procumbens Linn., Amaranthus spinosus Linn., Laportea aestuans (Linn.) chew., Acalypha fimbriata Schum. & Thonn., and Lufa cylindrica Mill were the most dominant species on the dumpsite with RIVs of 8.40, 8.17, 7.54, 7.21, 6.38 and 5.79 respectively. Talinum fruticosum (L.) Juss., Tridax procumbens L., Euphorbia heterophylla Linn., Spermacoce ocymoides Burm f., and Tithonia diversifolia (Hemsl.) A. Gray were most dominant on farmlands with RIVs of 13.74, 7.05, 6.60, 6.07, and 5.57 respectively. Dumpsite flora had higher diversity (H`=3.501) than control plots (H`=3.294). The dominance value (0.0486) was low compared to the control farms (0.07131). The lora of the two sites were grouped by habitatt preference.Higher species diversity and pervasive presence of invasive Tridax procumbens linn., Laportea aestuans (Linn.) chew., and Lufa cylindrica Mill. On dumpsite indicated potentials for phytoremediation, and candidacy as functional groups and bio-indicators of ecosystem health.
Climate change and the potential distribution of the invasive shrub, leucaena leucocephala (lam.) de wit in Africa
(2023) Obiakara, M.C.; Olubode, O.S.; Chukwuka, K.S.
Leucaena leucocephala, previously known as ‘miracle tree’ because of its numerous agroforestry uses has become a seri¬ous invasive species in tropical regions. Despite the risks associated with the spread of L. leucocephala, changes in its distribution with respect to climate are poorly understood, particularly in Africa where it has been widely introduced in more than 30 countries. To provide first-line information for the management of L. leucocephala, we examined its poten-tial distribution in Africa using ecological niche modelling. We identified bioclimatic variables that determine the global distribution of L. leucocephala, and calibrated niche models using MaxEnt and species occurrences recorded between 1973 and 2013. The potential distribution of this species was estimated from model projections in Africa based on cur¬rent and future climatic conditions. We tested the hypothesis of niche conservatism for L. leucocephala by comparing its climatic niche in Africa to that of its native range. Under current conditions, L. leucocephala is constrained between 30° S and 20° N in Africa, with the broadest distribution in East Africa. High rainfall areas in Central Africa with no known records of this species hitherto, were found to be highly suitable for its establishment. We predicted a significant decre¬ment in the extent of areas at risk of invasion by L. Leucocephala under changing climates in Africa. Our results revealed that the study species occupies a similar but non-identical climatic niche in Africa in relation to its native niche. Climate change is likely to impede the spread of L. leucocephala in Africa.
Climate change and the potential distribution of the invasive shrub, leucaena leucocephala (lam.) de wit in Africa
(2023) Obiakara, M.C.; Olubode, O.S.; Chukwuka, K.S.
Leucaena leucocephala, previously known as ‘miracle tree’ because of its numerous agroforestry uses has become a seri¬ous invasive species in tropical regions. Despite the risks associated with the spread of L. leucocephala, changes in its distribution with respect to climate are poorly understood, particularly in Africa where it has been widely introduced in more than 30 countries. To provide first-line information for the management of L. leucocephala, we examined its poten-tial distribution in Africa using ecological niche modelling. We identified bioclimatic variables that determine the global distribution of L. leucocephala, and calibrated niche models using MaxEnt and species occurrences recorded between 1973 and 2013. The potential distribution of this species was estimated from model projections in Africa based on cur¬rent and future climatic conditions. We tested the hypothesis of niche conservatism for L. leucocephala by comparing its climatic niche in Africa to that of its native range. Under current conditions, L. leucocephala is constrained between 30° S and 20° N in Africa, with the broadest distribution in East Africa. High rainfall areas in Central Africa with no known records of this species hitherto, were found to be highly suitable for its establishment. We predicted a significant decre¬ment in the extent of areas at risk of invasion by L. Leucocephala under changing climates in Africa. Our results revealed that the study species occupies a similar but non-identical climatic niche in Africa in relation to its native niche. Climate change is likely to impede the spread of L. leucocephala in Africa.
Climate change, impacts and mitigation: Nigerian experience
(2010) Ogunyemi, S.; Awodoyiu, R.O.; Olubode, O.S.
Climate has continued to change for millennia. The various anthropogenic factors have accelerated the change to the extent that what used to be subtle natural changes have become measurable and observable changes. These anthropogenic factors have resulted in the generation of greenhouse gases (GHGs) and their emission to the atmosphere and the depletion of the ozone layer. The GHGs, especially carbon dioxide (COz) generated from various combustion activities; methane (CHf generated from rice paddies and flooded areas as a result of anaerobic fermentation, and from ruminating cattle and nitrous oxide (NfO) generated from decomposition of nitrogen fertilizers and livestock wastes trap some of the heat (infrared) that radiate from the earth. The ozone layer at the upper stratosphere which shields the earth specifically from the ultraviolet (UV) light is constantly being destroyed by the immense quantities of chlorine released by volcanoes and other natural emissions, and by chlorine releasedfrom human-made chlorofluorocarbons (CFC, HCFC, HFC, PFC). The most visible effect of climate change is global warming, which has disrupted the thermodynamic balance of the earth, with some regions unnaturally gaining more heat than the others. This rise in earth temperatures has resulted in continued melting of ice caps, glaciers and sea ice, resulting in a rise in global sea levels of between 20cm and 60cm. The Nigerian Niger Delta is under threat of climate related flooding, habitat destruction and species loss. The coastal erosion in the Niger Delta occasioned by sea-level rise is already a menace, especially, regarding destruction of mangrove vegetation which constitutes an important stabilizing system in the brackish ecosystem. Already, 18,803 square kilometers was reported destroyed and 0.21 million people displaced by up to 2-meter coastal sea-level rise. The receipt of increased UV on earth not only increased the temperature on earth, but has serious implications on human health, causing melanoma skin cancer, cataracts and sunburn and altering human's immune system. Afforestation, reforestation, zero-tillage, replacement offossilized fuels with environment-friendly fitels and energy sources like bio-diesel and sustained public awareness programmes are suggested as ways to mitigate the emission of GHGs.
Complexities of local cultural protection in conservation: the case of an endangered African primate and forest groves protected by social taboos
(2017) Baker, L.R.; Tanimola, A.A.; Olubode, O.S.
Globally, some species and habitats receive protection through local belief systems (e.g. indigenous religions) and informal institutions (e.g. social norms and taboos). Where such systems represent the only form of protection for threatened species or environments, they may be critical to the survival of those taxa and sites. We evaluated the effectiveness of long-standing social taboos protecting the Endangered Sclater’s monkey Cercopithecus sclateri and forest groves in a community complex in Nigeria. Across its range (southern Nigeria), Sclater’s monkey is effectively protected only through informal institutions. At our study site, we conducted a census of the monkey population; measured the area of sacred groves; and compared our findings with estimates from  and , respectively. We observed a % increase in the monkey population (from  to  individuals) in a core survey area. No groves that we assessed in  had been fully cleared. Although we observed a decline in tree cover for several sacred forests, most groves used regularly by monkeys had changed little. The social taboos related to monkeys and sacred groves remain largely intact; however, other factors threaten the monkey population and remaining forests in this community complex, including the removal of tree patches to accommodate the construction of large residential buildings and the demand for cropland, as well as increased dumping of waste in forested sites. This study highlights the conservation importance and limitations of local cultural protection, as well as the challenges presented when such protection conflicts with community-perceived
Considerations for using occupancy surveys to monitor forest primates: a case study with sclater’s monkey (cercopithecus sclateri)
(2011) Baker, L.R.; Todd, W.A.; Olubode, O.S.; Garshelis, D.L.
Count-based indices and distance sampling are widely used to monitor primate populations. Indices are often confounded by variation in detectability, whereas distance sampling is generally ineffective with species that flee or hide from observers and where it is difficult to accurately measure detection distances. We tested occupancy modeling as a means to monitor Sclater’s monkey (Cercopithecus sclateri), an endemic of Nigeria. We evaluated effects of survey methodology, habitat, and human disturbance on detection probability and site occupancy. Average detectability was high (p = 0.81), but varied substantially between two observers. Occupancy was highest in areas with intermediate levels (20–40%) of farmland and secondary forest, and was unaffected by human disturbance. Sampling plots (4 and 6.25 ha) did not concurrently contain[1 monkey group, were likely closed to monkey movements during the replicate surveys of each plot, and were spatially separated so that it was unlikely the same group was observed in [1 plot. These conditions enabled the conversion of occupancy to group density. Scaled to 6.25 ha, model-weighted occupancy averaged 0.230 (SE 0.103), yielding an estimate of 3.7 groups/km2 (95% CI 1.4–7.7 groups/km2). Because some groups straddled plot boundaries, we assumed that half of these groups were inside the plots, resulting in an adjusted estimate of 3.1 groups/km2. Our results illustrate that occupancy can be suitable for monitoring vigilant forest primates where detection distances are difficult to measure. However, special attention is required to choose spatial and temporal scales that accommodate the method’s closure and independent-detection assumptions.
Correlates with the distribution and abundance of endangered sclater’s monkeys (Cercopithecus sclateri) in Southern Nigeria
(Blackwell Publishing Ltd, Afr. J. Ecol., 2007) Baker, L.R.; Olubode, O.S.
A distribution survey of the endangered Sclater’s monkey (Cercopithecus sclateri) was conducted over a wide area in southern Nigeria using forest surveys and hunter interviews. Sclater’s monkey, Nigeria’s only endemic primate species, is restricted to a land area of about 28,500 km2 in the densely human-populated, oil-producing region of southern Nigeria. Results indicate that this species is not as rare as previously thought; we confirmed its presence in 27 formerly unknown sites. Based on encounter-rate and distribution data, Sclater’s monkey is one of the two most abundant diurnal primate taxa across its range. However, the species primarily occupies isolated and degraded forest fragments. Although hunting is widespread, selective hunting of larger-bodied primate taxa offers some respite for the smaller Sclater’s monkey. We encountered this species more frequently in forests with relatively high hunting pressure, possibly indicating competitive release in the heavily hunted forests of southern Nigeria. Long-term persistence of Sclater’s monkey, which has no official protection throughout its range, depends on the willingness of hunters to target smaller-bodied wildlife (effortprofit trade-off), local bushmeat demand and protection of key forest fragments and the few larger forests in the region.
Distribution and abundance of sacred monkeys in igboland, Southern Nigeria
(Wilcy-Liss, Inc., 2009) Baker, L.R.; Tanimola, A.A.; Olubode, O.S.; Garshelis, D.L.
Although primates are hunted on a global scale, some species are protected against harassment and killing by taboos or religious doctrines. Sites where the killing of sacred monkeys or the destruction of sacred groves is forbidden may be integral to the conservation of certain species. In 2004, as part of a distribution survey of Sclater’s guenon (Cercopithecus sclateri) in southern Nigeria, we investigated reports f sacred monkeys in the Igbo-speaking region of Nigeria. We confirmed nine new sites where primates are protected as sacred: four with tantalus monkeys (Ch'lorocebus tantalus) and five with mona monkeys (Cercopithecus mona). During 2004-2006, we visited two communities (Akpugoeze and Lagwa > previously known to harbor sacred populations of Ce. sclateri to estimate population abundance and trends. We directly counted all groups and compared our estimates with previous counts when available. We also estimated the size of sacred groves and compared these with grove sizes reported in the literature. The mean size of the sacred groves in Akpugoeze (2.06 ha, n = 10) was similar to others in Africa south of the Sahel, but larger than the average grove in Lagwa (0.49 ha, n = 15). We estimated a total population of 124 Sclater’s monkeys in 15 groups in Lagwa and 193 monkeys in 20 groups in Akpugoeze. The Akpugoeze population was relatively stable over two decades, although the proportion of infants declined, and the number of groups increased. As Sclater’s monkey does not occur in any official protected areas, sacred populations are important to the species’ long-term conservation. Despite the monkeys’ destruction of human crops, most local people still adhere to the custom of not killing monkeys. These sites represent ideal locations in which to study the ecology of Sclater’s monkey and human-wildlife interactions.
Distribution of Mimosa diplotricha C. Wright nil invasive weed in relation to other herbaceous weeds in Agrarian ecosystems of Ibadan, Nigeria
(2017) Tanimola, O.O.; Awodoyen, R.O.; Olubode, O.S.
Mimosa diplotricha is an invasive weed whose spread can have negative impacts on plant biodiversity and agriculture.''In this study, a floristic survey was used to assess the distribution of Mimosa diplotricha in relation to other weed species in Ibadan, Nigeria. Florisiic survey was conducted using Jm x lin quadrat at 0.5 km intervals on transects along major roads of six purposively selected agrarian ureas based on prevalence oj Mimosa diplotricha, frdm Ibadan metropolis to: Alai jo, Akanran, lyana-Offa, Idi-Ayunre, hldo and Susa. The entire arpas are within 7° 14-7°30'N; 3°48'-4°04 E and altitude 127-261 in asl). The Relative Importance Values (RIV, %), relative density and relative, frequency, diversity indices {Species richness (S), Shannon-Wiener (11) and Evenness (J)} were determined. Eighty-six pHint species from twenty-eight families were enumerated. The RIV of Mimosa diplotricha was highest in all areas: 17.1 (Susa), 22.5 (Alcufo), 3L5 (Idi-Ayunre), 23.3 (lyana -Ojfa), 21.4 (Iddo), 36.0 (Akanran). While, the least RIV ranged from 0.31 (Luffa cylindrica; Sasa) to 0.97fCommelina erecta; Iddo). The Species richness (S), Shannon-Wiener (H) and Evenness (J) indices, in the areas were: 56.0, 3.1, 0.4 (Sasa); 31.0, 2.6, 0.4 (Alcufo); 44.0, 2.5, 0.3 (TdiAyunre); 40.0, 2.7, 0.4 (lyana Ojfa); 29.0, 2.6, 0.5 (Iddo) and 35.0, 2.0 and 0.2 (Akanran), respectively. The'high diversity indices revealed random distribution of species. However, high RIV values of Mimosa diplotricha in all surveyed axes showed that it is fast becoming the dominant weed species in Ibadan and may be a threat to
Diversity and floral composition changes in intensively cultivated practical year training program farm of the university of Ibadan, Nigeria
(2018) Jude, G.E.; Olubode, O.S.
Higher Institutions where agriculture is taught are required by National University Commission to have large areas of land for practical and demonstration activities. The lands are often cultivated intensively for decades under the same soil management practices, thus making them to become invaded with weeds which overtime become adapted to the ecosystem at the expense of soil productivity. The study was conducted to determine the species composition, invasiveness, spatial distribution of weed species and diversity of weeds on the site for Practical Year Training Programme (PYTP) of the Faculty of Agriculture, University of Ibadan in two consecutive years. The PYTP farm was floristically surveyed by using 21 plots of 150 m2 each and a strip of 5 m round was maintained for edge effects. Six (1 m2) square quadrats (126 in all) were randomly laid on each plot to enumerate the herbaceous flora of the farm. Flora composition, frequency and density values were evaluated for Relative Importance Values (RIV, %) following standard procedures. Soil of the farm was routinely analysed for its adequacy for agricultural purposes. A total of fifty two (52) plant species in seventeen (17) families were enumerated in the first year while a total of thirty (30) plant species belonging to fourteen (14) families were enumerated in the second year. In the first year, Tridax procumbens had the highest Relative Importance Value (11.73), distantly followed by Cynodon dactylon (6.44). Tridax procumbens was prevalent in plots not subjected to crop rotation. The abundance of plants was low on clay soils. Margalef index (12.81), Mehinick index (6.959), and Dominance (0.05262) indicated high overall species diversity, high species diversity in each plot, and low overall dominance respectively. In the second year, Gomphrena celosioides had the highest RIV (18.66) followed by Panicum maximum (12.43). Three soil types (sandy loam, loamy sand and clay) were identified. The soils were acidic (pH 4.7 – 4.8). Sandy loam and loamy sand soils had comparatively higher organic matter content than clay soil. The nitrogen concentration of the soils was generally low (0.6-1.33 g/kg). The Practical Year Training Programme land of the University of Ibadan is not productive and therefore should be allowed to rest for a long period of time. Conservation agricultural practices are recommended for the land anytime it is to be cultivated to deter further degradation.
Diversity and phytosocioiogy of herbaceous flora in the wetland area of the university of Ibadan integrated fish farm, Nigeria
(2014) Adegbite, K.S.; Olubode, O.S.; Awodoyin, R.Q.
University of Ibadan Integrated Fish Farm was assessed using stratified random survey of 108 randomly laid quadrats within 18 plots of900 m2 each. Floral identification, species diversity, relative importance value (RIV), ordination and classification analyses followed standard procedures. Presence of invasive plants were determined. Routine soil analyses conducted followed standard procedures. Soil data were analysed using ANOVA (P=0.05). Significantly different means were separated with least significant difference at p-0.05. The site contained 144 plant species distributed within 38 families. Species richness was high across all plots except plot two. Species dominance ranged from 0.03 to 0.1. RIV ranged from 0.15 to 6.3; Amaranthus viridis had the highest and Aspilia bussei, lowest. Multivariate analyses indicated two ecosystem structures comprising a small densely vegetated near-pristine wetland and a large sparsely vegetated perturbed area. Floral dichotomy included 12 positive preferential groups of 86 stands and 6 negative preferential groups of 22 stands. The soil was Silty-clay. Invasive plants species with high RIVs were Althernanthera brazilensis (1.33) and Bidens pilosa (0.15). pH (6.60), potassium (0.58), sodium (2.23), calcium (11.57), total carbon (38.04), total nitrogen (2.68), and phosphorus (50.63) were higher for soils collectedfrom under forest plots than in non-forested plots (5.85, 0.15, 0.16, 5.42, 5.1, 1.15 and 16.42 respectively). The vegetation of University of Ibadan Integrated Fish Farm was moderately high and stable. The wetland is not pristine, and prone to degradatior. Construction activities for aquacultural purposes should maintain the wetland for sustainable biological productivity. The flora should be assessed periodically.
Diversity and proximate composition of herbaceous components of old oyo national park, nigeria in relation to wildlife conservation
(2009) Olubode, O.S.; Awodqyin, R.O.; Ogunyemi, S.
The diversity of wildlife in Parks depends on availability and distribution of flora feeding resources. Abundance and proximate relationships between wild plants and wildlife may determine conservation potentials of a Park. The composition and diversity of species in three wetlands (Ibuya, Ipade-Aya and Ajalcu) in Old Oyo National Park, Nigeria were studied in dry (February-March) and wet (September- October) seasons of 2004-2006. Herbaceous flora of the three wetlands were systematically assessed using 5000 m2 plots on which two 100 m diagonal transects were superimposed to enumerate all low-growing plants that rooted within thirty randomly selected 1 m2 quadrats. Four most abundant plant species in two families were selected for proximate analyses. Three topsoil samples of each site were randomly collected and analysed for physicochemical properties. Hyparrhenia involucrata Stapf. and Andropogon tectorum Schumach were the most abundant herbs in the wetlands. Ipade-Aya had the highest Shannon-Weiner (H1) and evenness (J) values of 1.6 and 0.7 respectively. Ibuya had H'=1.0 and J=0.5; while Ajalcu had H'=1.0 and J=0.5. The protein contents of the forage grasses significantly (P<0.05) ranked in the order: Andropogon tectorum > Andropogon gay anus Kunth > Hyparrhenia involucrata > Hyparrhenia rufa (Nees) Stapf. Soils of the wetlands were mostly similar, except Ajalcu which was sandy loam. Fauna populations at the three sites were low. The highest detected faunal populations were nine at Ibuya, and three each at Ipade-Aya and Ajaku. Available nutritious grasses may not continue to sustain wildlife populations. Further research should consider increasing forage for faunal conservation.
Edaphic factors and soil organic carbon storage potentials under different land use types in omo biosphere reserves Nigeria
(2022) Oladoye, A.O.; Oyelowo, O.J.; Olubode, O.S.; Ojo, E.O.; Bakare, O.O.; Henry, C.A.
The regulatory functions of the soil are getting attention among scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. A study was carried out to investigate the SOC storage potentials under different land use types (Tectona grandis, Gmelina arborea, Acacia siamea, Pinus carrribea, and Natural forest) in Omo Biosphere Reserves Nigeria. The impact of the five important land use types on SOC and other soil properties were analyzed. Soil core samples were taken at two depths (0-10 and 10-30cm) to observe the changes in soil properties with depth. Laboratory analyses were carried out to determine the bulk density, soil pH, soil moisture, and soil organic carbon. The data obtained were analyzed using the Analysis of variance (ANOVA) and Duncan Multiple Range Test (DMRT) was used to separate the means while Principal Component Analysis (PCA) was used to examine the relationship between the soil parameters. Correlation analysis was carried out to examine if a relationship exists between soil depth and different land use on soil organic content and all other soil properties. The result showed that at both depths there is no significant difference between depths in pH, soil organic carbon, and soil moisture except for bulk density. Total Soil Organic Carbon stored in soil was highest in Teak plantation (3.1), followed by Acacia (2.17), and Natural forest (0.92), and at depth SOC was high in 0 10cm depth. The maximum value of bulk density (gcm3) was found high in 0-10cm at depth and was found high in Teak plantation (1.68) followed by Pinus plantation (1.67) and Acacia plantation (1.53). The distribution of moisture content showed no significant difference but the highest moisture was stored in Natural forest plantation (39.04), followed by Teak plantation (34) and Gmelina plantation (20), and the lowest in Pinus carribea plantation (10). Moisture content across depth showed that 0-10cm depth stored the highest but the 10-30cm depth () had the highest pH. Among the land use types, Teak plantation (5.84) had the highest pH, followed by Gmelina plantation (5.4) and Natural forest plantation (5.23). Results showed that SOC storage in soils can be influenced by different land use systems.
Edaphic factors and soil organic carbon storage potentials under different land use types in omo biosphere reserves Nigeria
(2022) Oladoye, A.O.; Oyelowo, O.J.; Olubode, O.S.; Ojo, E.O.; Bakare, O.O.; Henry, C.A.
The regulatory functions of the soil are getting attention among scientists and Soil Organic Carbon (SOC) is an important indicator of soil health. A study was carried out to investigate the SOC storage potentials under different land use types (Tectona grandis, Gmelina arborea, Acacia siamea, Pinus carrribea, and Natural forest) in Omo Biosphere Reserves Nigeria. The impact of the five important land use types on SOC and other soil properties were analyzed. Soil core samples were taken at two depths (0-10 and 10-30cm) to observe the changes in soil properties with depth. Laboratory analyses were carried out to determine the bulk density, soil pH, soil moisture, and soil organic carbon. The data obtained were analyzed using the Analysis of variance (ANOVA) and Duncan Multiple Range Test (DMRT) was used to separate the means while Principal Component Analysis (PCA) was used to examine the relationship between the soil parameters. Correlation analysis was carried out to examine if a relationship exists between soil depth and different land use on soil organic content and all other soil properties. The result showed that at both depths there is no significant difference between depths in pH, soil organic carbon, and soil moisture except for bulk density. Total Soil Organic Carbon stored in soil was highest in Teak plantation (3.1), followed by Acacia (2.17), and Natural forest (0.92), and at depth SOC was high in 0 10cm depth. The maximum value of bulk density (gcm3) was found high in 0-10cm at depth and was found high in Teak plantation (1.68) followed by Pinus plantation (1.67) and Acacia plantation (1.53). The distribution of moisture content showed no significant difference but the highest moisture was stored in Natural forest plantation (39.04), followed by Teak plantation (34) and Gmelina plantation (20), and the lowest in Pinus carribea plantation (10). Moisture content across depth showed that 0-10cm depth stored the highest but the 10-30cm depth () had the highest pH. Among the land use types, Teak plantation (5.84) had the highest pH, followed by Gmelina plantation (5.4) and Natural forest plantation (5.23). Results showed that SOC storage in soils can be influenced by different land use systems.
Eutrophication of Dandaru reservoir in Ibadan, Nigeria in relation to land-use and mechanical desilting
(2016) Olubode, O.S.; Akpan, P. E.
Eutrophication of water bodies is mainly caused by influx of Nitrogen and phosphorus compounds from land-use. Understanding relationship water reservoirs and farmlands will foster management of ecological resources. This study examined the link between eutrophication and land-use at Dandaru reservoir at Agodi, Ibadan, Oyo State and effect (s) of mechanical clean up on the reservoir. The Vegetation, soil of Lawn (L), bush fallow (BF), vegetable farm (VF) and Agodi Gardens (AG), and water quality of Dandaru reservoir in Ibadan were systematically assessed pre- and post-desilting following standard procedures. Forty 0.25 m2 quadrats were floristically assessed for Relative importance values (RIV) and Shannon-Weiner index (H`). Three randomly extracted bulked and sub-sampled top soil of each land-use were analysed physiochemically. The reservoir was sampled for phosphate, Organic carbon (TON), nitrate (TN), dissolved oxygen (DO) and pH in three replicates at entry, mid and exit points of the river. Data were analysed using ANOVA at p=0.05. Means statistical differences followed Fisher’s LSD. Fifty one plant species were enumerated pre-desilting consisting of 15, 22, 29 and 11 species in L, BF, VF and AG respectively; 22 plants were enumerated post-silting consisting 10, 10, 8 and 8 species in L, BF, VF and AG respectively. legumes ranged in RIVs from 4.217-8.397 in BF and VF. Pre-desilting, VF had highest H` (3.334), while AG had lowest (1.988). Post-desilting, Lawn had highest H` (1.956) while VF had lowest (1.679). P, TOC, TN and pH were significantly different in all land-uses with TN (0.81±0.02g/kg) and TOC (7.83±0.05g/kg) in BF. Phosphorus (0.31±0.03g/kg) was high at AG pre-desilting. Post-desilting, TN (32.90±3.37g/kg) and TOC (2.24±0.04g/kg) were significantly high in lawn. Pre-silting, pH and DO were significantly different at all points, lowest at midpoint (6.73±0.04mg/l and 7.89±0.30mg/l respectively); post-silting, pH (7.87±0.00) and DO (9.54±0.0Img/l) increased at midpoint.The legumes in agricultural lands most likely contributed to eutrophication of Dandaru reservoir. However, desilting offered temporary restoration. Cessation of agricultural activities around Dandaru reservoir with its periodic assessment will prevent eutrophication