Rainforest Zone Research Articles

Development of Water Repellent Polish for the Pointing and Finishing on NBRRI Earth Block Walls

Assessment of the challenges facing the adoption and promotion of NBRRI CSEBs reviewed the issues of instability or erosion of the brick wall surfaces, a case study reveals that it is a common problem to all walls made of this block within different zones of the country. The quest to proffer sustainable solution to these challenges necessitated this research work. The study aimed at producing a locally sourced water repellent polish for painting and finishing on NBRRI earth block walls. A substance (slurry) that can resist moisture penetration into adobe walls through the surfaces. The materials used were sourced from the rainforest zone of the country, investigated and tried with different mix ration depending on the Oxide composition in phases. The first phase featured the following materials and equipment; limestone, crab soil, periwinkle shell, Termite mould, natural clay, Hydrated lime (Ca (OH)2, Soluble Rubber (Top Bond) and Distilled water for mixing. Equipment includes; Weighing balance of 0.1g accuracy, sieve no 2020 (75pm) stirring rod, brushes and spray. In this phase soluble rubber was tried differently with the materials in various oxide composition applied on the existing CSEB walling unit, from observation some performed well while others performed moderately. The second and the third phase of the trial employed limestone and hydrated lime (Ca (OH)2 as the main stabilizer to activate reaction between the combination of any of the samples that contained high silica and a certain percentage of aluminium oxide (Al2CO3) x H2O(c) to produce an effective result as the Ca (H2O(s)) react in the presence of air to give Ca2SiO3(s) a solid that is stable in water, and applied on CSEB wall surfaces for observation across wet and dry Season.

A comparative study of population structure and genetic diversity of commercial and indigenous chickens from different agro-ecological zones in Ghana using SilicoDArT and SNP markers

Chicken production, both in the local and commercial sectors, contributes significantly to human livelihood and food security. Precise use of diverse genetic resources is primary in breeding programs. The study analyzed the genetic diversity and population structure of commercial chickens and indigenous chicken ecotypes from three different agro-ecological zones (Semi-Deciduous Rainforest Zone, Guinea Savannah, and Coastal Savannah) using SilicoDArT and SNP markers, utilizing whole-genome sequencing and phenotypic data. Phenotypic data were collected from 72 indigenous chicken ecotypes across the three AEZs, and 32 commercial birds kept at the Kwame Nkrumah University of Science and Technology (KNUST). DNA samples used for sequencing were obtained from 88 chickens (62 indigenous chicken ecotypes and 26 commercial chickens). A total of 54,995 SilicoDArT and 85,396 SNPs markers were generated from DArTseq genotyping. After filtering, 44,784 SilicoDArT and 58,353 SNP were used for genetic diversity and population structure analysis. Both markers showed high reproducibility and call rate. Polymorphic information content (PIC) values ranged from 0.00 to 0.50, while ≥ 50 % showed PIC values more than the median. Furthermore, we obtained FST values, Nei’s genetic distance, dendrogram analysis, and principal component analysis (PCA) of commercial and indigenous chickens. The FST and Nei’s genetic distance showed that there is high genetic diversity between the commercial chickens and the indigenous chicken ecotypes. However, there was low genetic diversity among the indigenous chicken ecotypes. The PCA analysis indicated a clear separation between the commercial and indigenous chicken ecotypes, while no clear separation was observed between the indigenous chicken ecotypes. The phenotypic data and the dendrogram indicated that naked and frizzle genes do not markedly alter the genetics of indigenous and commercial birds, and their influence on economic traits may be solely determined by the prevailing environmental conditions. The results indicate that there is high genetic differentiation between commercial and indigenous chickens based on SilicoDArT and SNP markers. The indigenous chickens from the agro-ecological zones have low genetic diversity and might have a common origin. Naked neck and frizzle genes do not markedly alter the genetic performance of birds in terms of economic traits. Therefore, the superiority of birds carrying these genes in economic traits may be solely due to environmental variation.

Assessing the adaptability and resilience of cowpea and maize varieties to various climatic zones of Côte d’Ivoire

The cultivation of cowpea and maize is common, but it is carried out without a prior selection of varieties that can effectively adapt to the specific climatic conditions of the zones. This study aimed at assessing cowpea and maize varieties in different ecological zones in order to identify the resilient varieties with respect to zone. The experiments were conducted in three different climatic and vegetation zones of Côte d’Ivoire: tropical rainforest zone, forest-savannah mosaic, and sub-Sudanian savannah in South, Centre-West, and North Côte d’Ivoire, respectively. In each zone, a randomized complete block design was used. Four varieties of both cowpea and maize were used. The analysis of variance was realized using grain yield data to compare varieties and climatic zones. The best varieties obtained differed according to the zones. Thus, in the tropical rain forest zone, the cowpea variety KVX780-6 and maize variety Violet de Katiola were the most yielding, with 593.30 kg ha−1 and 1270.84 kg ha−1, respectively. In forest-savannah mosaic, the cowpea variety KVX745-11P and maize variety SR21 obtained the highest yields, with 761.82 kg ha−1 and 2212.99 kg ha−1, respectively. The cowpea variety Tiligre and maize variety SR21 were the most productive in the sub-Sudanian savannah zone, with yields of 327.31 kg ha−1 and 1797.3 kg ha−1, respectively. Overall, the highest yield of cowpea (513.20 kg ha−1) and maize (1757.13 kg ha−1) were observed in forest-savannah mosaic. The best cowpea and maize varieties identified in each zone can be recommended to farmers.

Assessment of maize-cowpea intercropping response to row orientation in diverse agro-ecologies of Côte d'Ivoire

The stability of cropping systems in a changing climate context depends on numerous factors, including row orientation, to optimize the use of environmental resources. This study aimed to evaluate the performance of agricultural systems based on the row orientation of cowpea (Vigna unguiculata) and maize (Zea mays) in three different ecological conditions in Côte d’Ivoire, in 2020 and 2021. An experimental design with plots divided into three complete randomized blocks with six subplots per block and three repetitions was set up, varying the row orientation in intercropping and monoculture. Row orientation, cropping system used, and ecological zone significantly influenced crop yield and its components. In intercropping, cowpea (tiligré) showed the best yields when oriented North–South (NS) in the tropical rainforest zone and the sub-Sudanian savannah, while East–West (EW) orientation was optimal in the forest-savannah mosaic zone. In contrast, maize (GMRP18) yielded the best in intercropping when rows were oriented East–West, regardless of the season. In monoculture, cowpea yielded best when oriented EW in the tropical rainforest zone (488.17 kg ha−1) and in the forest-savannah mosaic zone (1262.12 kg ha−1), while NS orientations were preferable (228.6 and 259.54 kg ha−1) in the sub-Sudanian savannah zone. For maize monoculture, EW orientation was also preferable. Throughout the study, for both seasons, the highest yield advantages in maize-cowpea intercropping were obtained in EW orientation, regardless of the ecological zone. Overall, the forest-savannah mosaic zone yielded the best cowpea yields (1262.12 and 663.9 kg ha−1).

Ứng dụng GIS và tư liệu viễn thám đánh giá biến động lớp phủ rừng tại vùng đệm Vườn Quốc gia Cát Tiên thuộc địa phận huyện Tân Phú, tỉnh Đồng Nai.

The Cat Tien National Park in the South of Vietnam represents a protected ecological area, it is located in tropical rainforest zone. For assessment of forest cover change in three buffer zones of Cat Tien National Park, namely Nam Cat Tien, Nui Tuong and Phu An at Tan Phu district, satellite images (Landsat 5 TM and Landsat 8 OLI) take in 1990, 2000, 2010 and 2020 were used. Land use/land cover were classified by 5 categories using maximum likelihood classifier (MLC) method, result of constructing a key for image classification showed that images without reference data for classification have over 83.50% of map accuracies. After classification, differentiation of forest land use/landcover was analysied in each year. Deforestation and agricultural area reduction took place in 1990 - 2020 period. Besides, study has quantified changes in forest cover during periods: 1990 - 2000, 2000 - 2010 and 2010 - 2020. As a result, findings show that the extents of forest cover have decreased from 5522.22 ha to 2620.98 ha during the period of 1990 - 2020. Maps of forest status as well as changes in forests can be used for forest resource management activities under the Cat Tien National Park management.

Phenotypic characterization and analysis of genetic diversity between commercial crossbred and indigenous chickens from three different agro-ecological zones using DArT-Seq technology.

Indigenous and were used to study genetic diversity and population structure analyses. Polymorphism information content (PIC) values ranged from 0.0 to 0.5, with 21,285 SNP markers (35%) being in the lowest PIC value range (0 to 0.15) while 13,511 (commercial chickens have developed unique adaptations to their environments, which may include nutrition, pathogens, and thermal stress. Besides, environmental pressures and artificial selection have generated significant genome-wide divergence in chickens, as those selection pressures contribute a considerable evolutionary force to phenotypic and genotypic differentiation. Herein, we determined genomic diversity of indigenous chickens from semi-deciduous rainforest (SDR), coastal savannah (CS) and Guinea savannah (GS) agro-ecological zones (AEZs) in Ghana and commercial crossbreds (CC) reared at the Kwame Nkrumah University of Science and Technology (KNUST). We generated SNP markers from 82 chickens (62 indigenous chicken ecotypes and 26 commercial crossbred ecotype) using DArT-Seq technology. A total of 85,396 SNP markers were generated and after filtering the data, 58,353 markers 21%) were in the highest PIC value range (0.45 to 0.50). The CC were more genetically diverse than the indigenous birds, with the highest expected heterozygosity value of 0.220. Between the commercial crossbreds population and the indigenous ecotypes, pairwise FST values were estimated to be 0.105 between CS, 0.096 between SDF, and 0.133 between GS. Furthermore, PCA analysis showed that the CC, SDF and GS chickens clustered together and are genetically distant from the commercial crossbred. We herein show that chickens from the AEZs studied can be considered as one population. However, due the abundance of agro-byproducts in the SDR compared to the CS and GS, chickens from the SDR AEZ had better growth compared to their counterparts. It is suggested that the genetic diversity within the local ecotypes could form the basis for genetic improvement.

Prevalence of African Mosaic and Morphological Characterization of Cassava (Manihot esculenta Cranz) Varieties in Two Agroecological Zones of Cameroon

The objective of this work is to conduct an epidemiological study of African cassava mosaic and to characterize the diversity of local cultivars in circulation in the monomodal and bimodal rainforest zones of Cameroon. Disease-related parameters (incidence and severity index) were studied as well as morphological parameters (plant height, leaflet color, petiole color, lobe length, number of lobes, number of branches, petiole length). The results show that 96 cassava varieties were identified with 89 local varieties and 07 improved varieties. Diseased plants showed a symptom severity index of 1 to 5, which could reduce production by half in the areas considered. The leaf color was dark green, the number of branches was 3, the lobe and petiole lengths were 16.46 and 22 cm respectively, while the number of lobes was 5 the disease incidence for the two agro-ecological zones as a whole is 57.58% for a symptom severity index of 3. The epidemiological study reveals that the desease incidence of both agro-ecological zones was 57.58 % for a symptom severity index of 2 corresponding to 40 %. In the humid forest zone with monomodal spray the average incidence was 49.74% and a leaf attack rate was 29.03 % in the locality of Njombé (Cameroon's littoral region). At Ekona in southwestern Cameroon, the average incidence was 63% and leaf attack index was 1 corresponding to 20 %. In the bimodal rainforest zone (central Cameroon region), the average incidence was 60 % for a leaf attack rate was 37.11%. The expected results highlight a relatively worrying situation. Principal Component Analysis (PCA) confirms the convergence of tolerance towards the mosaic and grouped the different varieties into more or less homogeneous groups according to the morphological and epidemiological cassava descriptors. The results of the present work show that the introduction of cassava local varieties tolerant to mosaic disease in middling could be an alternative for the control of the cassava mosaic disease.

Effect of Weight at First Mating on the Performance of New Zealand White Rabbit Population in the Rainforest Zone of Nigeria

It has been generally accepted that for breeders to embark on intensive production of rabbits there is a need to use appropriate body weight rabbit that has better performance. To provide such information, this study was therefore carried out to determine the effect of weight at first mating on the performance of the New Zealand White rabbit population at the University of Benin Teaching and Research Farm. The rabbits were grouped into four based on their weight before the first service (1.00 to 1.49kg, 1.50 to 1.99kg, 2.00 to 2.49kg, and 2.5kg and above) as weight groups 1, 2, 3, and 4 respectively. The rabbits were raised under acceptable management. The experimental animals were fed a commercial diet of 18% CP and 2700kcal/kg ME. Data collected were weight of doe before service (WBS), number of time served (NTS), litter size at birth (LSB), litter size at weaning (LSW), litter weight at birth (LWB), litter weight at weaning (LWW), pre-weaning mortality percentage (PWM), gestation length (GLT), and stillbirth (SBT). The data were subjected to statistical analysis using the R statistical package version 3.3.3 (2017). Significant means were separated using the Duncan Multiple Range Test. The results obtained showed an increasing trend with body weight at first service. The mean values for LWB were 40.08±1.04, 43.83±2.16, 49.26±2.93 and 45.57±3.74 g for weight groups 1, 2, 3, and 4, respectively. Rabbits in weight 2 and 3 had a higher CV of 30%. Mean LWW ranged from 366.20±26.92 in group 1 to 442.90±29.74 in weight group 4. The average LSB was 4 kits. Litter sizes at weaning (LSW) were 3 kits except for group 4 with 4 kits. The body weight at first mating had no significant effect (P>0.05) on the performance traits. Gestation length (GLT) and pre-weaning mortality (PWM) showed significance (P<0.05). Gestation length (GLT) was highest in weight group 4 with mean days of 32.14±0.40 and the least in group 3 (30.53±0.09). Percentage SBT was highest in group 3 (10.48%) and none was recorded in group 4, 0.00±0.00. Percentage PWM was highest in groups 1 and 2 with 23.25% and 1.50%, respectively, while there was no PWM recorded in groups 3 and 4. The results of the efficiency of gain of offspring from the weight group were not significantly different (P>0.05) except for mortality which showed a significant difference (P<0.05). Rabbits from weight groups 1 and 3 showed better performance but for the high mortality in group 1, it will be better to mate rabbits for the first time at weight group 3.

Impact of pesticides exposure on Archachatina marginata snails in four Cameroon monomodal rainforest sites.

Cameroon monomodal rainforest zone has a strong agricultural activity and is therefore exposed to pesticides. Furthermore, the area possesses climatic factors that favor the growth of Achatinadea snails known as African giant snails, a delicacy for the local population. The present study aimed to evaluate pesticides contamination (less vs more exposed areas) through assessment of exposure and impact on Achatinadea snails. Achatinadea snails were collected within intensive agricultural areas (Njombe and Kribi rural) and in areas with less agricultural activity (Ebodje and Dibombari). Collection was performed at night between July and September 2020 using an adapted square kilometer method. Type, number, weight, and size of the collected snails were analyzed and compared using Welsh's One-way Analysis of variance (ANOVA). After removing the soft part from the shell, the presence of pesticides was determined using mass spectrometry. Histological analysis of kidney and ovo-testis was performed using eosin-hematoxylin staining. Results showed that the main variety of snails collected are Archachatina marginata. In areas with less agricultural activity, snails are bigger than those from more agricultural areas heavily using pesticides. Furthermore, pesticides detection showed that glyphosate, but not metalaxyl, is present in animals coming from all the collection sites. Cypermethrin was found in all the samples except in those from Dibombari. Histology revealed that the structure of the kidney and ovo-testis of snails from more exposed areas is impaired. In conclusion, this study revealed that some pesticides are transferred to snail and impair the structure of important organs.

Cacao Water Use, Canopy Characteristics and Yield as Affected by Irrigation and Shade in a Rainforest Zone of Nigeria

There has been need to improve crop and water productivity considering the need for agricultural intensification in the realm of increasing water scarcity and drought in several regions of the world. Information is limited about the effects of irrigation on cacao water use (evapotranspiration) especially, during the terminal drought situation of the dry season in the rainforest agroecology of Nigeria. The effects of shade and dry season irrigation was examined on tree water use, canopy characteristics and pod and bean yields of cacao (Theobroma cacao L.). Treatments were 2 by 2 factorial combinations of irrigation intervals (5 and 10 days) and shade and no-shade (open sun) laid out in a split-plot scheme with 3 replications. Shade regimes constituted the main plots and irrigation intervals the sub-plot treatments. Irrigation water was delivered at 5-and 10-day intervals on emitter lines using gravity drip system. Irrigation combinations affected cacao canopy characteristics (leaf area index) and light integrals (photosynthetic active radiation (PAR) and canopy light attenuation (extinction coefficient, k) within the cacao field. The unshaded-irrigation had higher proportion of incident radiation (I) transmitted (Io) through the canopy (IO/I), PAR intensity, and canopy extinction coefficients (k) compared with the shaded plus irrigations at 5-and 10-day intervals. Cumulative seasonal irrigation (12119 and 8483 mm), soil moisture contents (19.6 to 13.7 %) and cacao water use (ETc: 3.8 and 3.2 mm.day-1) differed for the respective 5- and 10-day irrigation intervals. The unshaded plus 5- and 10-day irrigation intervals out-yielded the shaded-irrigation combinations for number and weights of pods and beans. Pod and bean yields were significantly different under irrigation treatments, the 5-day irrigation produced greater number and heavier pods and beans compared with the 10-day irrigation. For the shade-irrigation combinations the range of values were: weights of pods (78000 to 6000 kg/plant), beans (4.8 to 3.2 t/ha) and water productivities: Irrigation WUE: 0.45 to 0.33 mm/kg/ha) and ET WUE: 0.11 to 0.09 mm/kg/ha). The shade-irrigation strategy enhanced cacao leaf area index, water use and bean yields and ameliorated climate stress.

GIS-based Characterization of Land Use, Land Cover Patterns and Microclimate of Agricultural and Agroforestry Landscapes in a Rainforest Zone of Nigeria

There is increasing need for development of sustainable land use and landscape management practices to avert accelerating trends of land, water and ecosystem degradation and for climate mitigation. This study characterized land use and land cover patterns and microclimate of permanent (forest, agroforestry, fallow, cocoa, oil palm, citrus and ornamental plant field) and annual crop land use systems in a rainforest zone of Nigeria using space-based remote sensing technology. The goal is to evaluate land use and land cover patterns and microclimate along agricultural and agroforestry landscapes in a rainforest zone of Nigeria. Land use types were: permanent (forest, agroforestry, fallow, cocoa, oil palm, citrus and ornamental plant field) and annual cropland. Vegetation indices (Normalized Difference Vegetation Index: NDVI, Normalized Difference Water Index: NDWI and Soil Adjusted Vegetation Index: SAVI) were deployed for characterizing land use vegetation cover patterns in relation to vigour and health in addition to responses to weather variables (temperature and rainfall). The NDVI intensities of vegetation cover from the land use types showed differences in vigour and health of vegetation during the rainy and dry seasons of 2017 to 2019. The NDWI of vegetation cover intensity indicates differences in moisture conditions of vegetation cover, the vegetation of the land use systems had more water content (received more rainfall) in 2017 compared to 2018 and 2019 during the rainy season while during the dry season of 2019, NDWI intensity was highest compare to 2018 and 2017. NDVI and NDWI also showed that vegetation cover of permanent land uses had better vigour and health compared to annual (maize) field. SAVI was applied to correct NDVI of vegetation cover patterns of land use types with reference to canopy gaps (soil brightness within canopy especially in spots where vegetation cover is sparse). High SAVI intensities were obtained during rainy compared to the low values during dry season (sparse vegetation cover). Decreasing order of SAVI intensities were agroforestry, oil palm, ornamental plant field, citrus, cocoa, fallow land and maize crop field. Result from the correlations among vegetation indices (NDVI, NDWI and DSAVI) were strong association (R2 = 1) among the years and seasons. The strong R2 values imply that less than 10% of changes in NDWI (the explanatory variables) can be explained by changes in NDVI and SAVI (the dependent variable). Temperature and rainfall differed within months and years of study. Temperatures were highest for March, April and May while rainfall was highest for September of 2017 and 2018 and in October, 2019. Significantly lower rainfall amounts were received for January, February, November and December. The vegetation indices (NDVI, NDWI and SAVI) indicated vigour and water contents of the land use types within seasons and years as well as responses to weather variables (rainfall and temperature in particular). The biophysical findings from this study may advance capacities to cope with climate change challenges and ecosystem conservation. Information generated will find use as strategies for ecologically sound and sustainable land use systems and policy for mainstreaming climate mitigation in in the study area.

Impact of repeated mass ivermectin administration using a community directed approach on L. loa infection in Chrysops silacea of the rain forest and forest savanna of Cameroon

BackgroundLoiasis is an endemic filarial infection in the rainforest zone of West and Central Africa. Repeated annual community-directed treatment with ivermectin (CDTI) delivered for several years to control onchocerciasis has been shown to reduce the prevalence and intensity of Loiasis in some Loa loa-Onchocerca volvulus co-endemic areas. However, the impact of these multiple rounds of CDTI on entomological indicators of loiasis transmission is not known, and was therefore assessed in this study in areas with contrasting histories of CDTI. MethodsThe study was conducted in the East, North-west and South-west 1 CDTI project sites of Cameroon. Two communities per CDTI project were selected for fly collection and dissection. Ivermectin treatment coverage was documented in these areas, and this was correlated to Chrysops infection and infective rates. A total of 7029 female Chrysops were collected from 6 communities of the 3 CDTI projects (East, North-west, and South-west 1) and from 2 communities in a non-CDTI district (East). ResultsChrysops biting densities and parous rates were significantly reduced in the North-west and South-west sites post-CDTI, while in the East, biting densities were similar in non-CDTI and CDTI sites, with higher parous rates observed in the non-CDTI site. Infection and infective rates in the East non-CDTI site were 4.4% and 1.8% respectively, as compared to 3.3% and 1.3% in the CDTI site after 10 ivermectin rounds (there were no baseline data for the latter). In the North-west site, significant reductions in Chrysops infection and infective rates from 10.2% and 4.2% respectively, to 3.5% and 1.2 (after 9 rounds of ivermectin treatment), were recorded following CDTI. In the South-west, infection rate significantly increased from 1.74% to 2.8% and infective rate remained statistically unchanged after 14 rounds of CDTI (0.45% - 0.40%). Similar trends in Mean Head L3 were observed except in the East site where this indicator was similar in both CDTI and control sites. Only in the North-west site did monthly transmission potentials decrease significantly. ConclusionThis study demonstrated that the impact of repeated annual treatment with ivermectin for the control of onchocerciasis using community directed delivery approach on the entomological indicators of loiasis varies with bioecological zones. Community directed treatment with ivermectin induced a significant reduction in the entomological indicators of loiasis in the North-West project site which lies in forest savanna area. A non-significant decrease was observed in the East project site and in contrast, a significant increase was observed in the South-West 1 project site which both lies in the rainforest zones.

Analyses of Climate Variability and Trends in the Oil Palm Belt of Ghana

The current production of oil palm in Africa has been severely limited by long periods of drought and perennial floods due to the increased rates of climate change. The study was aimed at assessing the climatic variability trends in 7 major Oil Palm growing areas (Benso, Mpohor, Bogoso, Twifo Praso, Kade, Juabeng and Brewaniese) located in the oil palm belt in Ghana spanning the semideciduous and the wet evergreen rainforest zones of Ghana using 30 years of historical weather data (1993-2022). The data was analysed to evaluate the extent of seasonal changes in weather over the 30-year period using the Statistical Package for Social Sciences (SPSS 20.0 version), using descriptive statistics and time series analysis. Trend analysis was conducted using the non-parametric Mann-Kendall (MK) and Sen’s slope estimator tests. A seasonal trend in rainfall was observed at all sites with maximum levels observed between May and July as well as a minor rainy season in September to Mid-November. The Mann-Kendall trend analysis showed a generally increasing trend at most stations in rainfall, temperature and solar radiation. A generally increasing trend in annual rainfall was observed from 1993-2022 with significant trends at Mpohor and Juabeng. The trend was higher in the moist evergreen rainforest zone than in the semi-deciduous rainforest zone. An average increase of 6.7 mm/yr in rainfall trend was observed for the period. An increasing trend in monthly maximum, minimum and mean temperatures were also observed. Significant increases in mean temperatures were observed at Bogoso (0.022°C/yr), Benso (0.018°C/yr), Juabeng (0.011°C/yr) and Mpohor (0.017°C/yr). The trend in mean annual solar radiation was generally not significant except in Benso where the mean solar radiation increased at the rate of 0.044 MJ/day. Higher drought levels in the first half year combined with very heavy rains later in the year are features of the ongoing climate change menace.

Forest vegetation cover in Bu Gia Map National Park, Vietnam

Understanding the composition of tree species is essential for establishing conservation priorities. Bu Gia Map National Park is in the tropical rainforest zone of Southeast Vietnam. This paper is to analyse and assess tree species composition and biodiversity conservation in Bu Gia Map National Park. The diversity of plant species in Bu Gia Map National Park was studied to provide baseline information for conservation and sustainable management processes that will prolong the life of National Park. The results obtained from the study conducted on the plant species composition and forest vegetation in this national park revealed a total of 786 species, spanning 430 genera and 132 families, across three divisions of vascular plants: Polypodiophyta, Pinophyta, and Magnoliophyta. Among these are 300 species of timber plants, 270 species of medicinal plants, 62 species of edible plants, 74 species of ornamental plants, 40 species of industrial plants, 28 species of fiber plants, and 12 species of plants with unknown use. Notably, during the investigation period, Goniothalamus vietnamensis Ban and Myxopyrum smilacifolium Blume were newly recorded in the forest vegetation of Bu Gia Map National Park. The study also describes a variety of forest vegetation in the area, identifying two major forest vegetation types within Bu Gia Map National Park.

Effect of Moisture Content on the Yield of Mahogany Seed Oil

African Mahogany (Khaya senegalensis) is an important tree in Africa. A deciduous tree, reaching up to 35m in height on fertile soils. It has a diameter of up to 1.5 m with 8-16 m bole. The bark is dark grey or pink with red latex. The plant is commonly found in all the Northern States and around South Western States of Nigeria in the rain forest zone. The plant begins to produce fruit after 15 – 25 years throughout the dry season. The fruit is woody capsule, 4-10 cm long and dehisces at maturity. The seeds have a very low moisture content which is good for oil extraction hence its selection. For the purpose of this study, Mahogany seed, distillation apparatus, jaw crusher, water distiller, chiller, soxhlet extractor, oven, digital weighing balance, n-hexane, are the materials used for the extraction. According to Soxhlet procedure, oil and fat from solid material are extracted by repeated washing (percolation) with an organic solvent, usually hexane or petroleum ether. 325 g of mahogany seed was used in 25-x 80-mm thimble. The Sample has an oil yield of 63.58%, with a cake of 206.62g after extraction and a moisture content of 9% as a result of volatile substance due to high vapor pressures. Further studies on the extraction of oil from mahogany seed is recommended with method other than soxhlet extraction method using n-hexane as extracting solvent as the best method of extraction for end users.

Morphological Characterization of Ant Species Found Within the Tropical Rainforest Zone of Calabar, Nigeria

Aim: This study was carried out to unravel the morphological variations that exist among ant species in the Rainforest zone of the University of Calabar Community. Method: Ants were collected from three locations (Botanical Garden, Cameroon and Unical Farms) within the University of Calabar. Direct hand-picking method and the pitfall traps method were utilized for sample collection. Thereafter, different morphological parameters including total length, head width, eye length, etc. were measured and analysed. Results: The results obtained showed a dominance of Formicinae with 3 species (35 %), followed by Myrmicinae with 2 species (30 %), and lastly Ponerinae and Dolichoderinae and Dorylinae with one species (5 %) each. A total of 7, 4 and 2 ant species were collected from the University of Calabar Botanical Garden, Cameroun and University of Calabar Farm sites respectively. Out of the 7 ant species, 3 species (50 %) were common to all the locations on campus, while another 2 species (45 %) were found exclusive to the Botanical Garden site. Conclusions: This work established that the morphology of ant faunas found in various areas of the campus varied significantly. It also concluded that the morphological space occupied by the ant fauna of the Botanical Garden was significantly larger than those collected from the other locations.

Assessment of Weathering Intensity and Pedogenesis of Lithosequence Located in Two Agroecological Zones of Nigeria

Elemental oxides can help to identify processes of soil formation and the degree of soil development. This study assessed soil development and weathering intensity in soils developed on schist and older granite in upland tropical rain forest and southern guinea savanna agro ecological zones of Nigeria. Soil profile samples were collected in each of the study locations. In the laboratory, total elemental oxides was determined using the energy dispersing X-ray Fluorescence (EDXRF) XRF SPEC (Minipal 4). The relative intensity of weathering of total elemental oxides was determined by choosing titanium as the suitable indexing element and the relative gain or loss of element was estimated using relative retained element (Ro) equation. Result obtained, revealed that SiO2 was the most abundant in the soils. Distribution of Al2O3 and CaO showed the direction of the pedogenic age. Older granite soil had higher values of Al2O3 and lower values of CaO. There was negative relationship of SiO2 with Al2O3 and Fe2O3. The trace elemental oxides were less than 1% and zirconium oxide was the most retained oxide in the soils. Soil which developed on schist retained more of the trace elements than soil on older granite. There was evidence of alitization, ferritization and desillication in the soils. Parent materials contributed to loss and gain of trace elemental oxides. Older granite soil was more weathered and pedologically older than schist derived soils.

Effects of Intercrops on Growth and Yield of Oil Palm in Rainforest Zone of Nigeria

Experiments were conducted between 2014 to 2015cropping seasons in a 3 to 5 years old oil palm fields at Ohosu Sub-Station, Benin City, a rainforest zone of Nigeria. The experimens showed the effects of intercrops (Cassava, Maize and Pepper) on the growth and yield of oil palm. Data were collected on the growth and yields of oil palm in oil palm-intertcropping system. Alley cropping was not detrimental to the growth and yield of oil palm, in particular canopy cover (1.71, 2.52 and 2.86 m) and mean fresh fruit bunch yields (88.8, 89.9. 93.6 kg/plot). The overall biological advantage of the alley intercrops is high in oil palm fields of ages 3 to 5years. The sole and intercrops of cassava, maize and pepper appeared to have optimized use efficiencies of resources (space and nutrients) in the alleys of oil palm of different ages (3 to 5years).

Dry season Irrigation Regime Effects on Water Use, Rootzone Moisture and Yield of Cacao (Theobroma cacao L.) in a Rainforest Zone of Nigeria

The humid tropics is characterized by wet-dry seasonal transitions, irrigation has the potential for building adaptation and resilience to climate stress for enhancing crop performance. A field trial was conducted to investigate the effects of dry season irrigation regimes on water use, root zone moisture dynamics and yield of cacao in a rainforest zone of Nigeria. Irrigation amounts computed as EPan x Pan coefficients were based on cumulative class A Pan evaporation. Irrigation treatments were coded as IrT1 (EPan x 1,0), IrT2 (EPan x 0.7) and IrT3 (EPan x 0.5). Irrigation water was applied 5-days interval and discharged via point source emitters (2.8 l/h discharge rate ) on drip lines laterally installed per row of trees. Mean irrigation requirements were 4.49 mm (9.81:9.6 l/tree/day), 3.14 mm (7.06:6.8 l/tree/day) and 2.44 mm (5.49: 4.8 l/tree/day) while total seasonal water applied were 121.19, 84.83 and 60.59 l/tree for IrT1, IrT2 and IrT3 respectively. Mean soil moisture contents and cacao evapotranspiration (ETc) were 52, 45 and 28 % and 4.54, 3.19 and 2.32 mm/day while evaporation from soil area wetted by emitters (EWz) were 5.65, 2.82 and 0.19 mm/day for respective IrT1, IrT2 and IrT3. The deficit irrigation strategies (IrT2 and 31 IrT3) imposed soil moisture deficit stress on cacao and produced lower pod and bean yields, it however enhanced water use efficiencies (25 and 44 %) and 30 and 50 % water savings. The study established suitable Pan coefficients for scheduling irrigation for cacao yield enhancement and drought (climate stress) amelioration.

Drought Stress Modulation by Biochar and Effects on Soil and Performance of Seedlings of Urban Forest Tree Species

Aims: This study was designed to examine the effects of watering regime and biochar on soil properties and performance of seedlings of urban forest tree species (UFTS) in the nursery. Study Design: The experiment was a 5 by 3 by 2 factorial scheme involving urban forest tree species, watering regimes and biochar amendment or not. Place and Duration of Study: seedlings of five UFTS were raised in the Nursery and Screenhouse of Wesley University, Ondo, a rainforest zone of Nigeria. Methodology: Seedlings of five Urban Forest Tree Species (UFTS) were subjected to watering at 80, 60 and 35% field capacity (FC) with or without biochar amendment. UFTS evaluated are: Bauhinia monandra, Delonix regia, Terminalia catappa, Dypsis lutescens and Veitchia merrillii. Results: Watering regime and biochar amendment exerted significant effects on soil physical and chemical properties, physiological attributes and biochemical constituents and performance o the UFTS evaluated. Watering at 60 and 35% FC increased bulk and particle densities but reduced significantly (P<.05) soil moisture content at field capacity compare with watering at 80% FC. Further, the 60 and 35% FC watering exhibited low N, available K+, Ca2+ and Mg2+. Addition of biochar to the variously watered soil considerably reduced bulk density but remarkably increased porosity, field capacity moisture and plant available moisture. Biochar amendment increased soil pH, total and volatile organic matter contents, available K+ and Ca2+, extractable Mg2+ and dissolved phosphate (PO43+). The responses of growth traits and biochemical constituents of UFTS to watering regimes was species specific. Relative to 80 % FC watering, seedling growth attributes reduced significantly under deficit water application (60 and 35% FC) in addition to remarkable accumulation of osmolytes (osmoprotectants) and enzymatic activities. Biochar amendment enhanced accumulation of osmolytes and activities of superoxide dismutase, guaiacol peroxidase and catalase enzymes of UFTS seedlings. Conclusion: Differential watering and biochar amendment affected soil physical and chemical properties and growth of UFTS seedlings evaluated. Biochar amendment of the variously watered soil enhanced seedling growth, and appear as effective strategy for improving soil properties and UFTS performance, and for mitigation of adverse effects of suboptimal watering.