FACULTY OF AGRICULTURE
Permanent URI for this communityhttps://repository.ui.edu.ng/handle/123456789/261
Browse
8 results
Search Results
Item Forest structure and tree stem carbon stock of Gambari Natural Forest Reserve, Oyo state, Nigeria(Faculty of Agriculture, University of Uyo, 2019-06) Falade, O. F.; Aderemi, S. A.Tree stems are major above-ground carbon pools in the tropical forest structure. Forest structure creates micro-climatic conditions for various ecosystem services. Natural and man-made disturbances cause changes in forest structure. However, the effect of forest structure dynamics on stem carbon sequestration is yet to be clarified in Gambari Natural Forest Reserve, Oyo State, Nigeria. Understanding influence forest structure dynamics on stem carbon could improve prediction of carbon sequestration potential of Gambari Natural Forest Reserve. Therefore, the aim of this study was to quantify forest structure and stem carbon stocks in Gambari Natural Forest Reserve. Ten sample (30m×30m2) plots were randomly demarcated in Gambari Natural Forest using stratified random sampling method comprising 5 sample plots in each identified canopy structures; closed and open. Tree stems ≥10cm diameter-at-breast-height (dbh) were identified, enumerated and species diversity indices computed. Total height (TH) and diameter were also measured for volume and carbon estimation. Data collected were analyzed using descriptive statistics and ANOVA α0.05. A total of 50 tree species representing 25 families were identified in Gambari Natural Forest Reserve and closed canopy had higher diversity indices than open canopy structure. The lower and middle canopy class had the highest stems/ha in both structures. Diameter distribution of closed and open structure expressed extended reverse J-shaped and rotated sigmoid curves, respectively. Tree stem carbon stock were 0.66Mg/ha and 0.436Mg/ha in closed and open canopy structure, respectively. Microphyla pterigota (12.11%) and Triplochiton scleroxylon (25.84%) contributed highest carbon stock in closed and open canopy structures, respectively. The study concludes that the closed canopy structure of Gambari Natural Forest Reserve offers good option for carbon sequestration strategies as its structure and tree composition influences its stem carbon stock. However, only few tree species contributed to the high stem carbon stock in the study area. Therefore, these tree species can be considered in the establishment of carbon credit for carbon sequestration in Nigeria.Item Seed pre-treatment and early growth performance of piliostigma thonningii (schum.) milne-redhead under nitrogen amendment in Old Oyo national Park, Nigeria(2023) Olubode, O.S.Survival of wildlife in protected areas is dependent on innate attributes and response of vegetation to climate change. Piliostigma thonningii holds promise for wildlife conservation in Old Oyo National Park, but its population is threatened by physical dormancy. There is dearth of information on long-term benefits of its seed pretreatment and early growth response to nitrogen fertilizer. This study assessed effects of acid scarification on germination and early growth of P. thonningii under different nitrogen application rates. Seeds harvested from three purposively selected seasonal wetlands in Old Oyo National Park (OONP) were treated with 1N H2SO4 at durations ranging from 0 – 120 minutes in three replicates. Germinated seeds were enumerated over a 14-day period. Top soils from the wetlands were randomly sampled using soil auger in three replicates for physical and chemical analyses, and for early growth study with Urea fertilizer at rates 0, 50 and 100 kg/ha in experimental pots in completely randomized design. Growth and dry matter were assessed using ANOVA at P.05. Germination commenced in control treatments at 14 days after plating (DAP) and was low (13.3%). Germination progressively increased in acid treatment. At 5 DAP for soaking for 30 minutes gave 46.67%; while it was 96.67% at 40 minutes at 14 DAP. Higher soaking times gave 100% germination by 14 DAP, but with low growth vigor. The response of P. thonningii to Urea application was significantly higher in number of leaves at 12 weeks than in other rates. Other growth parameters are not significantly different at all rates. The biomass yield of P. thonningii was 1.98 g 0.21and 2.6 g 0.36 root and shoot dry weights at 6 weeks after sowing (WAS); and 7.3 g 0.04 root and 6.4 g 0.95 shoot dry weights at 12 WAS. Piliostigma thonningii can restore and improve wildlife abundance to mitigate climate change effects in the Park.Item Woody flora diversity and carbon sequestration potential of university of ibadan teak plantation: a consideration for climate change mitigation in southwest nigeria(2016) Adeniji, S.A.; Olubode, O.S.Increase in atmospheric C02 is largely attributable to forest loss and carbon emission activities. Ability of forest plantations to sequester carbon for climate change mitigation is central to climate change mitigation, thus the study investigated carbon sequestration capacity of University of Ibadan Teak Plantation. The plantation (0.305 km2) is situated in a rainforest zone in Ibadan, Nigeria on 7°27'25.18'N; 3°54 14.04' E and a meaneievation of 209 m above sea level. Systematic sampling of 63 plots, each measuring 225 m2 was conducted on trees of >5 m bole height, >10 cm girth at breast height. Plots were distributed at 25 m intervals along seven line transects laid at 85 m apart. Species identification, relative importance value (RIV), diversity, multivariate analyses and carbon sequestration capacity of the forest were determined using standard procedures. Eighteen tree species in 12 families were enumerated. Tectonagrandis had highest RIV (49.347) with high dominance in many plots. Evenness index was generally low (below 0.5). Ordination biplotsindicated a mixed plantation. The carbon stock in the plantation was low (19.768 kg/ha/annum) compared to a typical tropical rainforest (600 kg/ha/annum), indicating 3.295% of carbon sequestration efficiency (CSE). The CSE of the plantation was low. This low CSE could be enhanced with adequate stocking density and removal of anthropogenic disturbances.Item 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.Item Determinants of Agricultural Intensification in Southwest Nigeria(2012) Oyekale, A.S.; Adepoju, A.O.Declining agricultural production in many developing countries has prompted increased use of some inputs while continuous cropping prevails. This study analysed the factors promoting different forms of agricultural intensification in southwestern Nigeria. Data collected from randomly selected farmers in selected states in southwestern Nigeria were used. Results show that farmers from Osun State have the highest indices of intensification with respect to land use intensity, fertilizer use intensity and crop diversification. The censored regression showed that lost working days, use of fertilizers, crop rotation, and having more inherited land increased land use intensity while use of organic manure, minimum tillage and poverty reduced crop diversification index. Fertilizer use intensity increased with the use of minimum tillage and household size while hired and family labour use intensity increased with household size. It was recommended that in the face of increasing land degradation, farmers’ access to fertilizer must be increased and efforts to reduce their poverty level must be promoted, among others.Item Climate induced changes on fishing activities of artisanal fisher folks in the coastal area of Ogun State(Agricultural Extension Society of Nigeria, 2015) Tijani, S. A.; Hassan, F. A.The climate induced changes on the fishing activities of artisanal fisher folks was investigated in Ogun Waterside Local Government Area of Ogun State. Daze were obtained from one hundred and twelve fisher men using simple random sampling technique. Data analysis was done through the use of descriptive and inferential statistics (Chi-square, t-test at p=0.05 Findings show most respondents were male (90.2%). married 92 2% and mostly used family labour (80.3%). Most (69.6%) of the respondents used fishing net of various mesh sizes and The majority 72.3% of the fisher folk used unmotorized boats and traditionals. Factors influencing changes in fishing activities include reduction of volume of fish catch (79 5%), damage of nets and boats by ocean surges (50.4%), wind storm (59.8%), flooding of dwelling house and fa—-srz 84.8% and problem of fuel wood (81.3%).Coping strategies emearked upon by the fisher folks to combat the effect of climate charge were channelization of beels to Atlantic ocean (90.2%), construction of plant foot bridges (83.9%) and the use of hard wood to construct canoes (61.6%). More than half of the respondents (56.2%) had unfavourable perception of climate change on the extinction of fish species There were significant relationship between age (age x2=7 730). household size (x2=155.479) and volume of fish caught. There was a significant difference between the volume of fish caught ten years ago and now (t=22.427). Climate change has impacted negatively on the fishing activities of the artisanal fisher folks. It is recommended that metrological stations need to be resuscitated and well equipped in human resource and modem equipment to function effectively in climate information dissemination.Item Reporting of climate change news in three Nigerian newspapers(Agricultural Extension Society of Nigeria, 2012-06) Fawole, O. P.; Olajide, B. R.The trend of news frame in the print media has implications for public perception of emerging development issues and actions that members of the public in general and farmers in particular will take in similar situations in the future. Combining the occurrence of climate change topical news variables and framing theories, this study content-analysed 111 climate news items framed in three Nigerian newspapers (the Guardian, Punch and Nigerian Tribune) between January 2010 and June 2011. Variables measured included news types, placement, sources, space allotted and period of report of climate change related stories. Data were analysed using both descriptive (frequency, percentage) and inferential (chi-square) statistics at p<0.05. Across the three newspapers, types of news reported as a result of climate change were flooding (41.4%) and oil spillage (27.9%). They were strategically placed at the front (32.4%) middle (36.0%) and back (31.5%) pages of the newspapers. The newspapers quoted news reporters of other media organizations (62.2%) and government officials (22.5%) as major sources of their climates change information. Space allocated to climate change news was higher in the Guardian newspaper (897cm2) compared to the Punch and. The Nigerian Tribune (884cm2). Major frames found in these dailies include warning, solution, disaster, awareness, call for assistance and blames. Types of climate change news did not affect placement given to coverage of such news (X2 =13.45; p=0.20). In spite of competition for space and prominence by wide range of development issues, climate change news coverage relatively enjoyed prominence. Therefore, efforts should be made to sustain this given the menace climate change portends in the face of any neglect by stakeholders especially the media.Item Economic Impact of Climate Change on Smallholder Crop Farms in Nigeria(2015) Odozi, J. CThe negative effect of Climate Change (CC) on agriculture across Africa has been well established. This underscores its global policy interest. In Nigeria, crop farming is climate dependent and farmholders often employ measures that are sub-optimal against climate risk. This raises the vulnerability of farming to CC uncertainty. For a long time, knowledge of CC perception by farmholders dominated the existing literature. However, information on economic estimates of damages and responses at the farm level is relatively scanty. Economic impact of CC on smallholder crop farms was therefore investigated. General household survey data on smallholder farms collected by the National Bureau of Statistics (NBS) in 2010 was used together with baseline climate observations from 1950-2000 and projections (2000-2050) of the World Climate Data Base (WCDB). Complementary data on population, soil and altitude for 774 Local Government Areas (LGA) were sourced from National Population Commission (NPC) and Food and Agriculture Organisation (FAO). Variables from NBS were farm value, farm revenue, crops cultivated, land size, area planted, household size and age. Variables from WCDB were Mean Temperature (MT) and Mean Precipitation (MP) for wet and dry seasons. Data was analysed using descriptive statistics, multivariate probit and Ricardian models at ∝0.05 Farm value and annual farm revenue were 156293.3 (10714.3-1619433.0) N/ha and 47837.1 (3966.2-2159244.3) N/ha respectively. Land size was 2.7±1.9 ha while area planted, household size and age were 2.3±18.2 ha, 5.2±1.6 and 51.3±15.3 years respectively. Baseline MT and MP were 26.3±2.9 ℃and 179.2±75.1 mm/month respectively for wet season and 25.9±3.0 ℃ and 22.3±24.7 mm/month for the dry season. Projected MT and MP were 27.61±3.0 ℃ and 192.3±61.6 mm/month for wet season and 27.5±3.0 ℃ and 25.6±29.3 mm/month for dry season respectively. Baseline MP increased the probability of cultivating sorghum (0.5%), cowpea (0.2%), and yam (0.1%) while it reduced the probability of cultivating millet (0.8%), rice (0.1%), cassava (0.1%) and maize (0.5%). Baseline MT increased the probability of cultivating millet (5.8%), rice (2.4%) and maize (51.5%) and reduced the probability of cultivating sorghum (0.7%), cowpea (2.1%), cassava (0.7%) and yam (36.7%). Projected MT reduced the probability of cultivating all crops with the highest probability on sorghum (10.5%). While the effect of projected MP on the probability of cultivation was mixed across crops, the highest probability of reduced cultivation was observed for rice (25.9%) and the least for maize (1.8%). Controlling for non-climate factors, climate change reduced farm value by 62.8% for the whole country and across agricultural zones by 8.2%, 41.9%, 7.2% and 41.0% for North central, North east, North west, and South west respectively except for South east that increased marginally by 3.4%. Climate change affected revenue and crop cultivation of smallholders and could affect food security in the near future. Impact was huge for the whole country and varies across agricultural zones. Use of stress tolerant technologies (irrigation, and drought tolerant seeds) and institutional support would enhance coping capacity against climate change risk