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Item Soil aggregates and carbon distribution in tectona grandis (linn. f.) plantation, Nigeria(2017-12) Falade, O. F.Soil and tree biomass are reservoir for carbon but there is uncertainty regarding their influence on soil carbon stabilization. Carbon associated with clay size aggregate is considered a major determinant of soil carbon accumulation. However, other aggregates are becoming relevant in the estimation of soil carbon accumulation. These limit the detail carbon estimation of soil. Therefore, soil carbon accumulation of aggregate sizes was estimated at two soil depths in Tectona grandis plantation. Six (30 x 30m2) plots were randomly demarcated in the plantation and 360 topsoil and subsoil samples were used for this study. Soil core samples were collected at five points at depths of 0-15, 15-30 cm in each plot for period of six months. Soil core samples collected were oven dried at 105 0C. Soil sample (100g) from each core sample was sieved into >2.0, 2.0-1.0, 1.0-0.5, 0.5-0.050 and <0.050 mm aggregate sizes using dry sieve procedure and proportions weighed. A subsample of 10g of each fraction was combusted in Muffle furnace at 500 0C for 4 hours and carbon content estimated. Carbon content of the bulk soil was also determined. Data were analysed using descriptive statistics, regression analysis at α0.05 The 0.5-0.05 mm fraction had the highest proportion of soil at top and subsoil (39 and 28%, respectively). Aggregate size of <0.05 mm had the highest soil carbon concentration at topsoil and subsoil. Exponential and logistic equations performed better on the basis of R2, F-value and Standard Error of Estimate. Therefore, carbon content of 0.5-0.05 and 1.0-0.5 mm aggregates accurately estimate carbon content of topsoil and subsoil using the exponential equation. Carbon content of fine silt size aggregate (0.5-0.05 mm) determined carbon accumulated. Exponential model of soil carbon is determined by the aggregate size distribution of each soil layer.Item Quantification of soil aggregate carbon in tectona grandis (Linn. f) plantation at University of Ibadan, Ibadan, Nigeria(Forestry Association of Nigeria, 2016-12) Falade, O. F.Forest soils are important reservoir for carbon and contribute to global climate mitigation. Fine clay size aggregate is considered a major determinant of soil carbon distribution. Other aggregate sizes are also important in carbon distribution and estimation. Therefore, soil carbon accumulation of aggregate sizes was quantified at two soil depths in Tectona grandis plantation. Six (30 x 30m') plots were randomly demarcated in the plantation and 360 topsoil and subsoil samples were used for this study. Soil core samples were collected at 4 comers and centre of each plot to depths of0-15,15-30 cm in each plot for period of five months. Soil core samples were oven dried at 105 °C. Soil bulk density and moisture content were estimated from the core samples. Soil sample (100g) from each core sample was sieved into >2,2-1,1-0.5,0.5-0.050 and <0.050 mm aggregate size fractions using dry sieve procedure and proportions estimated. Sub-sample (10g) of each fraction was combusted in Muffle furnace at 500 °C for at least 4 hours and carbon content estimated. Carbon concentration of the bulk soil was also determined. Data were analysed using descriptive statistics and ANOVA at a0 05 Bulk density ranged from 1.08 to 1.33 and 1.39 to 1.54 g/cm3 for subsoil and topsoil, respectively. Soil moisture content ranged from 17.23 to 23.36 and 14.08 to 22.15 cm for topsoil and subsoil, respectively. The 0.5-0.05 mm fraction had the highest values at top and subsoils (39 and 28% of the soil by weight, respectively) followed by 1 -0.5mm size fraction (27% of the soil by weight) at the topsoil and >2mm fraction (27% of the soil by weight) at the subsoil. Topsoil and subsoil had approximately the same proportion of 2-1mm and <50µm fractions. Fine silt (<0.05mm) fraction had the highest soil carbon concentration followed by sand size fraction (>2.0mm) and silt-size fraction (2-lmm) in topsoil and (0.5-0.05mm) in subsoil. The soil carbon associated with <0.05mm was greater than the >2mm fractions. The coefficient of Variation of carbon content were higher among the aggregates of subsoil than topsoil. The mean values of carbon content of bulk soil in topsoil were high than subsoil. Carbon concentration of fine silt size aggregate (0.5-0.05 mm) accurately estimate carbon content of topsoil and subsoil. Moisture content of the bulk soil influence carbon concentration of aggregate size of 1 mm and 0.05.Item Woody species diversity and regeneration patterns in Osun-Osogbo sacred grove, Nigeria(Ecological Society of Nigeria, 2017-12) Falade, O. F.; Bada, S. O.Osun-Osogbo Sacred Grove in Nigeria is one of the major biodiversity hotspots in sub-Saharan Africa with high plant diversity that has suffered considerable human-induced disturbance in the recent times. Therefore, this study aimed to quantify the canopy species diversity and regeneration pattern in the Sacred Grove. Three (0.09ha) plots were sampled in each identified forest type (old-growth, secondary-regrowth, and riparian forests) for the inventory of tree / sapling stems, and nested quadrats (5 x 5m2) for seedlings. All stems enumerated were identified to species level. Data on diameter-at-breast height (dbh) and number of individuals per species were collected by plot. The patterns of tree (dbh ≥ 10 cm) distribution and regenerating (dbh ≤ 10 cm) population were examined using Detrended Correspondence Analysis (DCA) while the regeneration status of the grove was assessed by comparing the Importance Value Indices (IVI) of the current stocking and regenerating populations of the tree species. A total of 75 vascular species representing 66 genera and 30 families were identified. Fabaceae (13 spp), Apocynaceae (8 spp.), Euphorbaceae (7 spp.) and Rubiaceae (7 spp.) contributed 47.5% of the flora. The first two component axes of DCA (79.59%) delineated three community assemblages along disturbance gradient in the tree population. In addition, the first two component axes of DCA (107.70%) identified four communities along composition and disturbance gradients in the regenerating population. Analysis of IVI indicated that Dialium guineense (4.11), Funtumia elastic (6.08) and Cola millenii (5.06) were dominant and the most widely distributed tree species in the Grove. Osun Sacred Grove is rich in vascular species diversity with diameter distribution showing poor growth and inadequate self- replacement of emergent tree species. Gap creation and appropriate cultural practices should be undertaken to improve the regeneration of the emergent species.Item Nutrient-use efficiency of tectona grandis (Linn. f.) seedlings on basement complex and ferric luvisol soils of Ibadan, Nigeria(Agricultural Research Council of Nigeria, 2011) Falade, O. F.; Oyeleye, B.The study investigated the use-efficiency of selected soil nutrient elements - Nitrogen (N), Phosphorus (P) and Potassium (K) in the synthesis of dry matter by Tectona grandis (Linn.f.) seedlings. T. grandis seedlings were grown on basement complex and ferric luvisol soils for 77 days after transplanting (DAT). Sixty polythene pots were filled with each soil type. Sixty soil seedling samples formed an experimental unit that was replicated three times making a total of 360 seedlings. Eight seedlings were selected at intervals of 7 days for the first 28 DAT and four seedlings for the remaining 42 DAT in each experimental unit. Composite samples of soil media and seedlings were taken at intervals of 7 days and chemically analyzed. The dried shoot and leaves were combusted at 500oC, for carbon content determination. Range of daily light intensity during the experiment was 3.5 to 6.2 Klux while daily mean temperature was 24.7 to 27.5oC. Total carbon and biomass results showed that photosynthetic efficiency and photosynthetic carbon production of seedlings grown on basement complex were not significantly different from those of ferric luvisol. It is concluded that an increase in biomass could not be a major indicator of an increase in biomass carbon production. Therefore, photosynthetic efficiency alone may not be an adequate indicator of efficient photosynthetic carbon fixation. The root/shoot ratio was higher than 1.0 in both soils, indicating higher biomass allocations to the roots of the seedling. The study provides basis for the estimation of the phosphorus and nitrogen-supplying power of ferric luvisol and basement complex soils,Item Determinant of carbon stabilization in tropical soils: a review of carbon sequestration potential of soil aggregate fractions(Forestry Association of Nigeria, 2018-03) Falade, O. F.Soils contribute to global climate mitigation through Sequestration of carbon. Soils that remain undisturbed for long period of time could be the best choice for carbon Sequestration. Quality of organic matter, land management practices and land use types had been considered the major factors influencing accumulation and stabilization of carbon associated with soil aggregate fractions. This understanding had limited the efforts at tracking carbon accumulation and stabilization of various aggregate fractions. However, other factors are becoming relevant in the evaluation carbon stabilization potential of various soil aggregate fraction in different soil texture and types. Therefore these factors require detail description. Organic and inorganic carbon compounds contribute to the soil carbon stabilization and subsequently, enhance carbon Sequestration. Understanding of the critical factors that control stabilization of carbon in soil aggregate fractions is limited. This limits the efforts on how to optimize carbon Sequestration potential among soil aggregate fractions and soil types and consequently, one of the reasons for unabated evolve of greenhouse gases from soils to the atmosphere. Therefore, brief description of factors that influence and optimize the Sequestration of carbon in tropical soils were reviewed. Hence, quantity and quality of organic matter, availability of basic cations; proportion of fine particle fraction in the soil; land management practices Option; organic and inorganic carbon concentration and soil moisture content were identified as the major factors influencing the soil carbon stabilization in tropical soils. The processes involve in carbon stabilization of tropical soils could be classified into Chemical and physical protecting mechanisms. Organic compounds derive from plant origin enhance soil particle aggregation while cations facilitate organo-mineral formation among soil fine particles. Surface area specificity is essential facilitator of organo- mineral formation among soil fine particles.Item Role of traditional institutions in conservation of plant diversity(Forestry Association of Nigeria, 2010-10) Falade, O. F.; Bada, S. O.Plant diversity is the vast variety of plant life and its ecological complexities existing in any region. Circumstances gave rise to diverse experiences among indigenous societies about plant wealth around them. Plants are integral for the survival of the traditional culture. Each community has a unique set of social institutions. Conservation efforts can be more efficient if it is based on deep knowledge of social institutions. Plant diversity Conservation thrive if synchronizes with improvement in human welfare. It is imperative that plant diversity Conservation and its sustainability should focus traditional institutions because of its voluntary compliance features and cost effectiveness. This review focuses on critical factors in traditional Institution that can affect Conservation of plant diversity. These factors include local attitude, land use change, indigenous knowledge, religious belief, and cultural traditions.Item Assessment of florsstic composition of forest undergrowth of international institute of iropscal agriculture (iita) forest reserve Ibadan, -Nigeria.(2014) Oladoye A.0; Aduradola; Olubode O.S.; Basiru A.O; Ezenwwenyi J.U.Assessment of understorey species of a tropical rainforest ecosystem in South-western Nigeria, exemplified by International Institute of Tropical Agriculture (IITA) forest reserve, Ibadan. A total of twenty-four permanent sample plots of 0.0625 ha were used for the assessment of understorey composition, density and frequency. Relative frequency, Relative Density and Importance Value Index (TVT), similarity, diversity and Detrended Correspondence Analaysis (DCA) statistics were used to analyse the data. The result showed a total of 3,833 individual from 128 species and 44 families (28 shrub, 57 trees, 33herbs, 2 grasses and 8 climbers ) were identified. Papilonaceae had the height number of species (11) followed by Moraceae (10), Albizia zygia had the height frequency of occurency (24), density of 169.33/ha. However Culcasia scandens had the height density of 299.33/ha. Highest Importance value index of 13.82 was recorded for Culcasia scandens, followed by Chromolaena odorata (11.80). The.least (IVI) 0.18 was recorded for Blepharis maderaspatensis, Carica papaya, Cissus pinata. Similarity between paired plots varied from 0.16 to 0.75, Simpson diversity (0.9529) and dominance of 0.0471, number of species present in each of the plotranged from 0-39. Plot 84 had the heighest species (39), high Eigen value (73.7%), length of. ordination space (-2 to 6) and the location of all the plots in the first quadrant indicated that the environment was stable indicative of minimal variation in floristic composition between plots and high heterogeneity of the site and species respectively. These findings showed that the IITA forest is diverse in species composition and the diversity of the understory may act as a catalyst for successful natural forest succession. Hence may be creating a more favourable environment for the establishment of native forest flora and habitat for fauna. Ultimately may be leading to conserving biological diversity. The study eventually concluded that a proper protection from human interferences and scientific management of undergrowth of the study area may lead to biodiversity rich site in the country.Item SIMULATION MODEL FOR PREDICTION OF STAND GROWTH AND YIELD OF Tectona grandis Linn F. IN AKINYELE LOCAL GOVERNMENT AREA, OYO STATE, NIGERIA(2014-08) UREIGHO, Nelly UfuomaEffective management planning tools for forest require growth and yield functions that can produce detailed predictions of stand development. Models such as Gamma Distribution Function (GDF), Weibull, Beta, and similar functions have been used to predict growth and yield of forest stands. However, information on the use of GDF in forest management has not been fully documented. The development of a program using Java programming language for GDF to predict growth and yield of Tectona grandis was studied in Akinyele Local Government Area, Oyo State, Nigeria. Stratified random sampling was used to select four different age classes of teak plantation namely; 11, 13, 22 and 59 years. Based on the size of each plantation, 7 and 8 temporary sample plots of 0.04 ha were selected from 11, 13, 22 and 59 year-old plantations respectively. Complete enumerations of trees (n = 433.) was done. Growth data sets collected include Diameter at Breast Height (DBH), total and merchantable heights. Basal Area (BA) and Volume were computed from measured variables. Data obtained were processed into tree level, stand level and size class. Parameters α and β for GDF were estimated from growth data. Based on the algorithm of GDF, α, β and n parameters, for the Java Program (JP) was written. Values obtained were fitted into the JP for growth and yield prediction. Linear and non- linear models were used to compare their predictive ability to the JP developed. At individual tree level using JP, the Observed and Predicted (O&P) values for height and BA ranged from 16.80-43.80 m, and 16.10-39.30 m; 2.49-4.51m2, and 2.45-4.31m2. Volume ranged from 2.09-10.54m3 and 2.04-12.03m3. Error rate varied from 0.00-9.00, -23.09-4.99 and -14.09-5.27 for height, BA and volume respectively. At stand level the O&P values for height, BA and volume from JP ranged from 17.10-28.30 and 17.90- 32.10 m; 2.55-3.69 m2 and 2.58-3.69m2; 2.25-3.69m3 and 2.28-3.69 m3 with error rate of -2.77-13.4; -0.10-5.65 and -0.10 -0.40 respectively. Size class level shape and scale parameter of GDF for diameter distribution ranged from 0.96-25.20 and 0.07-2.28 respectively. These values have better predictive power than non-linear and linear models which at individual tree level, O&P values for height and BA models of best fit ranged from 16.80-43.80m and 15.86-39.00 m; 2.49-4.51m2 and 2.50-4.98m2 . For volume, it ranged from 2.09-10.54m3 and 2.02-12.05m3 with error rate of -14.32-6.37. At stand level, O&P ranged from 17.10-28.30m and 17.95-32.18m for height; 2.55-3.69 and 2.59-3.72 m2 for BA and 2.25-3.69 and 2.29-3.65m3 for volume with error rate from -2.88-13.71; -4.58 -0.81 and -1.77-1.08 respectively. The R2 values for height, BA and volume models of best fit were 0.9490, 0.8981 and 0.9800 with the equations given as H= [1.31.08 + (H1.08 dom -1.31.08)1-e-0.06dbh/1-e-0.06*1.08 dom]1/1.08, 1n(B) = ln(0.32)+ 0.42(1/A)+ 0.77(lnH)+1.82(lnN)+1.89(H/A) and V= 1.62+22.38*DBH. The predictive ability of gamma distribution function for height, basal area and volume for teak plantation from the developed Java program consistently performed better than other models and could therefore be used for prediction of growth and yield in forest stands. Keywords: Gamma distribution function, Teak plantation, Growth and yield models, Forest management Word count: 498Item MODELS FOR GROWTH CHARACTERISTICS AND THEIR APPLICATIONS IN YIELD STUDIES FOR Pinus caribaea Morelet 1851 IN SOUTHWESTERN NIGERIA(2014-07) OYEBADE, Bukola AmooDevelopment of empirical models provides ample prospects of exploring established mathematical theories and relationships among tree growth variables for sustainable forest management options. However, there is inadequate information on modelling growth characteristics and productivity potentials of Pinus caribaea, a pulpwood species which is now being proposed for timber production in Nigeria. Hence, models for growth characteristics and their applications in yield studies for Pinus caribaea in southwestern Nigeria were investigated. Sixty Temporary Sample Plots (TSPs) of size 20m x 20m each and of different Age (A) series based on stocking density were sampled from Omo Forest Reserve (n=16 TSPs -15 and 21 years), Oluwa Forest Reserve (n=36 TSPs-18, 20, 35, 36 and 37 years) and Shasha Forest Reserve (n=8TSPs-27years) in Ogun, Ondo and Osun States respectively using stratified random sampling method. Growth variables: Diameter at Breast Height (DBH), Stem Quality (SQ) and Total Height (THT) were measured in each plot and Basal Area (BA), Stem Volume (SV), Tree Slenderness Coefficient (TSC), Crown Ratio (CR), Crown Projection Area (CPA) and Site Index (SI) estimated. A total of 1,592 trees were enumerated and each tree per plot classified into four canopy layers as dominant, co-dominant, intermediate and suppressed. Data obtained were used for modelling and categorized into individual tree level, size class level and whole stand level with Maximum Likelihood Estimation (MLE) technique adopted in 3-parameter Weibull Probability Distribution Functions (WPDF). Data were analysed using descriptive statistics, ANOVA, correlation and regression analyses at α0.05. Growth variables exhibited significant variations among the canopy layers with the dominant canopy layer having the highest mean THT of 14.9±0.2m and intermediate canopy layer lowest with 7.8±0.1m. Stem volume (1.4±0.04m3) and BA (0.1±0.002m2) were also highest in the dominant canopy layer. Slenderness coefficient however was highest (80.6±1.1) within the suppressed canopy layer while crown ratio was highest (0.27±0.001) in intermediate canopy layer. There were positive relationships between the growth variables across the stands with coefficients of correlation (r) ranging from 0.01-0.98 for individual tree level and 0.41-0.91 for whole stand level. Similar results of UNIVERSITY OF IBADAN LIBRARY iii correlation between Weibull parameters and other growth variables at the size class level were significant with r ranging between -0.72 and 0.92 with location parameter „a‟ of the WPDF having the highest positive association of r = 0.92 with DBH. The growth-yield models were of the forms lnCR =-3.5507+0.6263lnTHT+0.1558CPA+10.2339A 1, R2 =0.98 for dominant layer, lnCR = -3.1922+0.6363CPA+7.6876A-1, R2 = 0.994 for intermediate layer, lnTHT= 0.4547+0.0032lnSQ+0.6757CPA+0.1052A-1, R2=0.989 for suppressed layer and lnTHT=0.5872+0.5348CPA+0.0567A-1 with R2= 0.996 for co-dominant layer respectively. The overall best model among individual, size and whole stand categories was found within the whole stand level with R2=0.999 and of exponential form: lnSV=-0.7759+0.0001SI+0.0005A-1 +0.9532lnBA. The best adjudged growth-yield model among the canopy layers was found within the co-dominant layer. The selected whole stand growth-yield model was suitable for both current and future prediction of major growth characteristics and productivity potentials of Pinus caribaea in southwestern Nigeria. Keywords: Pinus caribaea, Growth variables, Yield models, Tree canopy layers Word count: 489Item CONFLICTS BETWEEN FORESTRY AND AGRICULTURAL LAND – USES IN OGUN STATE(2012-05) OTESILE, Adegboyega Ayodeji,Clash of interests between custodians of government Forest Reserves (FRs) in Ogun State and farmers operating within them, often results in conflicts causing disruption of socio-economic activities and sometimes loss of lives. Information on the causes and effects of these clashes would better inform policy makers and forestry professionals on workable and sustainable land-use practice. Therefore, factors responsible for such conflicts and their effects were investigated. Seven hundred and fifty farmers were randomly selected based on probability proportionate to size from 72 enclaves. This represents 30% of the total number of enclaves in the nine FRs in the State. In addition, 30% of staff of Ministries of Forestry and Agriculture (72 and 32 respectively) were randomly selected for questionnaire administration. Furthermore, 30% (32) of the timber contractors operating within the FRs were randomly selected for interview using an interview schedule. Data were collected on existence, causes and effects of conflicts, land hunger, accessibility to forestland and farming systems practised. Secondary data on the thrust of subsisting forestry and agricultural policies were obtained from the State Agricultural Policy, Federal land-use Act of 1978 and reports from the State Ministry of Forestry. Data were analyzed using descriptive statistics and logit model at p<0.05. Among the farmers, descriptive statistics revealed that 74.3% had unauthorized access to FRs, 68.1% were resident within FRs while 55.4% utilized lands approved by government for farming. Furthermore, 68.7% of the farmers identified taungya system and shifting cultivation as the prevalent farming systems practised. An average of two forest land encroachment cases were reported at each of Arakanga and Edun stream FRs yearly in the last 10 years while an average of 24 forest land encroachment cases was reported yearly in the last 10 years in Omo FR. Also, results of logit regression analysis revealed that the location of FRs where farmers operate (odds ratio = 2.39), rights of farmers to use forestland for farming (odds ratio = 2.19) and farm size (odds ratio = 1.52) are factors that are likely to cause conflicts over the use of forest lands in Ogun state. Furthermore, descriptive analysis of timber contractors‟ response revealed that, 72.6% identified destruction of cash crops during timber exploitation as cause of conflicts between them and farmers. State Ministries of Forestry and Agriculture officials identified loss of forests (27% and 25.2%), species (25.5% and 24%) and lives (22.5% and 22%), as effects of conflicts in the FRs. The thrust of the extant agricultural land-use policy made no provision to UNIVERSITY OF IBADAN LIBRARY iv penalize forestland encroachers. Conflicts in the use of forest land ensued between farmers and timber contractors on one hand and farmers and forest custodians on the other. The existence of land hunger in the forest reserves host communities, unauthorized access to forest land and absence of provision for penalty in the extant agricultural land use policy for forest encroachers encouraged activities engendering conflicts over the use of forest land. Keywords: Land-use conflicts, Forest policy, Forest reserves, Land hunger Word count: 481