ghanaopendata/ghanaian-research-english huggingface dataset:
Biogenically modified reservoir rock quality: A case from the lowermost member Paleocene Funing Formation, Gaoyou Depression, Subei Basin, China

Bioturbation can influence reservoir quality and is consequential to the producibility of a reservoir. The study of samples from the lowermost member of the Paleocene Funing Formation (E1f1), Gaoyou Depression, Subei Basin, shows how bioturbation affects reservoir quality. Techniques used to study the samples include petrography, pressure decay porosimetry, pulse decay permeametry, Field Emission Scanning Electron Microscopy, and Energy Dispersive X-ray Spectroscopy. Sample A is intensely burrowed by Taenidium, Scoyenia, Skolithos, Palaeophycus, and other trace fossils. Increased isotropy in sample A contributes to cleaner well-sorted burrows, relative to its surrounding matrix, and 67.18% augmented burrow porosity. Taenidium and Palaeophycus in sample B indicate 20.23% improved burrows porosity. Plant debris and/or root traces in sample C have a 3.68% reduction in porosity. In samples A and B, the arithmetic mean of permeability describes all horizontal fluid flows within burrows. In sample C, the geometric mean of permeability describes the fluid flow in all directions. Porosity is ≤ 11.2%, permeability ≤1 md in samples, and sample C log-derived porosity ≤0.33%. This study demonstrates that bioturbation together with depositional factors (sorting, grain size distribution, and mud matrix/burrow content) and diagenetic modifications (albitization, compaction, dissolution, kaolinization, and precipitation) control the quality of the high to intensely bioturbated (Bioturbation Index 4 to 5; 61–99 vol %) sandstone and siltstone reservoir facies of the E1f1.

Source: KNUST
Biological and Physico-Chemical Quality of Ground Water around the Old Municipal Refuse Dump Site at Ahenema Kokoben

The quality of ground water from the old municipal refuse dumping site at Ahenema Kokoben in the Ashanti region was determined by taking water samples from wells and boreholes within this area. A total of thirty samples were taken from these ground water sources. Parameters such as pH, electrical conductivity (EC), salinity, dissolved oxygen (DO) and total dissolved solids (TDS) were analyzed on site, while phosphates, nitrates and sulphates in addition to heavy metals such as zinc, lead, iron and copper were analyzed in the laboratory using standard protocols. The samples were also analyzed for feacal coliform, Escherichia coli (E. coli) and Salmonella contamination. The DO ranged from 2.17-3.54 mg/L and pH ranging from 2.17-3.54mg/L. Phosphate and sulphates were the highest nutrient concentrations recorded with mean values ranging between 1.27-1.45 mg/L and 1.17-1.74 mg/L respectively. Contamination with Lead was found to be the high in the study area with values ranging from 0.173-0.313 mg/L, these results were above the Ghana Standards Authority (GSA) set standards for lead concentration in drinking water. Salmonella was not recorded in this study. However, contamination with feacal coliform and E. coli was recorded with a range of 3.29×104 -3.81×104 CFU/100ml and 0.94×102-2.03×102 CFU/100ml respectively. The leaching of lead into water bodies occurs during high temperatures; therefore the constant high temperatures within the study area could have been the reason for high levels of lead. Water samples from this study area were found to be unwholesome for drinking according to both the WHO and GSA standards for drinking water, due to the presence of feacal coliforms and E. coli and then also high concentrations of lead.

Source: KNUST
Biological activity, toxicological effects, and bioactive chemical composition of an extract from the leaves of Ocimum Gratissimum .L.

Scientific bases for the traditional use of the leaves of O. gratissimum L. as a medical remedy for the treatment of stomach diseases and as a protectant of stored food grains from pests in Africa have been attempted. Although, the oil (and some of its fractions) from the leaves have been shown to inhibit the growth of gram-negative bacteria, which cause stomach disorders such as vomiting and diarrhoea, its prolong use as a drug for humans could be harmful since it was found to be toxic to brine shrimps (Artemia sauna) and tadpoles of the African toad (Bufo regularise) . The crude unseparated oil from the leaves strongly repelled Sitophilus zeaznais, S.oryzae, Callosobruchus sp. and Trogoderma granarium which are common insect pests of stored food grains in Ghana. The oil and its major component inhibited the growth of Phytophthora paniivora Butler and of blackpod lesion development on detached pods of cocoa (Theobroma cacao.L.) The major and biologically active fraction in the oil is spectroscopically and chemically proved to be thymol.

Source: KNUST
Biological nitrogen fixation potential by soybeans in two low-P soils of southern Cameroon

Biological nitrogen fixation (BNF) poten tial of 12 soybean genotypes was evaluated in conditions of low and sufficient phosphorus (P) supply in two acid soils of southern Cameroon. The P sources were phosphate rock (PR) and triplesuperphosphate (TSP). The experiment was carried out during two consecutive years (2001 and 2002) at two locations with different soil types. Shoot dry matter, nodule dry matter, and nitrogen (N) and P uptake were assessed at flowering and the grain yield at maturity. Shoot dry matter, nodule dry matter, N and P uptake, and grain yield varied significantly with site and genotypes (P\0.05). On Typic Kan diudult soil, nodule dry matter ranged from 0.3 to 99.3 mg plant-1 and increased significantly with P application (P\0.05). Total N uptake of soybean ranged from 38.3 to 60.1 kg N ha-1 on Typic Kandiudult and from 18 to 33 kg N ha-1 on Rhodic Kandiudult soil. Under P-limiting conditions, BNF ranged from -5.8 to 16 kg N ha-1 with significantly higher values for genotype TGm 1511 irrespective of soil type. Genotype TGm 1511 can be considered as an important companion crop for the development ofsmallholder agriculture in southern Cameroon

Source: KNUST
Biological nitrogen fixation potential of cowpea under composted millet glume and mineral fertilizer application in Sahelian Zone of Niger

Cowpea (vigna unguiculata L. Walp) is one of the cash crops grown in West Africa, where farming systems are characterized by low soil nutrient contents and limited fertilizer inputs. Therefore, the ability of cowpea to fix atmospheric nitrogen is very important in these farming systems. In this study conducted at N’dounga research station INRAN/ Kollo, the amount of nitrogen fixed by cowpea amended with millet glume compost and mineral fertilizer was assessed using the Total Nitrogen Difference (TND) method. The results showed that the combined application of composted millet glume and mineral fertilizer contributed more to nodulation than mineral fertilizer alone. Furthermore it was observed that 3 t ha-1 composted millet glume + 15 kg N ha-1 + 26 kg P ha-1 produced the highest grain yield (2764 kg ha-1). Grain N and P uptake were significantly higher in the combined compost and mineral fertilizer treatments. The 3 t ha-1 composted millet glume + 15 kg N ha-1 + 26 kg P ha-1 gave the highest nitrogen use efficiency (NUE) and phosphorus use efficiency (PUE). Correlation analysis showed a strong positive relationship (R2 = 0.84) between grain yield and nodule dry weight. Furthermore, a strong positive correlation (R2 = 0.98) was observed between grain yield and amount of nitrogen fixed. The proportion of nitrogen derived from atmosphere (Ndfa) in cowpea ranged from 33% to 78%. Combined application of composted millet glume and mineral fertilizer treatments had significant (P < 0.05) effect on the proportions of nitrogen derived from the atmosphere and the amounts of N fixed by cowpea. Nitrogen fixed was highest (69.57 kg ha-1) under 3 t ha-1 composted millet glume + 15 kg N ha-1 + 26 kg P ha-1 and represented 262.53% increase over the control (19.19 kg ha-1).

Source: KNUST
Biology of cylas spp. on some sweet potato varieties

Studies were conducted in the field to determine the effect of sowing depths of 2.5 cm, 5cm and 10 cm on Cylas infestation of the sweet potato varieties Sauti, TIS 8266, TIS 84/0320 and TIS 3017 which have been released recently by Crops Research Institute, Fumesua. Other parameters studied included the effect of number of leaves and branches on top 30 cm, vine thickness and internodes length on vine infestation. Investigations were also carried out to determine Cylas species and their population at 2, 3 and 4 months after planting of the sweet potato varieties. At harvest, tuber stalk length of the four varieties was measured and the soluble sugar content, dry matter and latex production were determined. Host preference experiments under no choice and free choice conditions were also investigated. The level of tuber infestation of the four sweet potato varieties by Cylas spp decreased with increasing depth of planting. - This may explain why sweet potato varieties with long tuber stalk had the least incidence of Cylas. The results also showed that Sauti which had the highest number of leaves and branches, as well as the thickest vine, had the highest incidence of vine infestation. There was an increase in the incidence of the weevil with time on the four sweet potato varieties. The sweet potato varieties used had varying levels of soluble sugar, percent dry matter content and latex production. It appears that optimal sugar content of sweet potato influences oviposition rate of the weevil which is reflected in the level of Cylas emergence. Higher weevil emergence in TIS 84/0320 may be attributed to its optimal level of soluble sugars present. There was no significant difference in weevil emergence in the no choice experiment. Significant differences, however, occurred in the free choice experiment. The results show the following order of decreasing magnitude of emergence in the four varieties: TIS 84/0320 >TIS 3017 >Sauti >TIS 8266. There was no varietal influence on the sex ratio of Cylas.

Source: KNUST
Biology and control of Planococcus Citri (Risso) (Hemiptera: Pseudococcidae) on five yam varieties in storage

The Citrus mealybug, Planococcus citri (Risso) seriously infests yams in storage. However, there is little information on the biology and control of P. citri on stored yam locally and the West African sub-region. Incubation and developmental periods, adult longevity, total number of eggs laid and life span of P. citri on stored yam (Disocorea species) were studied on five yam varieties stored in the laboratory with an ambient temperature of 26.0 - 30.0 0C and relative humidity of 70.0 -75.0 %. The mean life span values of female P. citri on the Dioscorea rotundata varieties Pona, Labreko and Muchumudu and the D. alata variety Matches and Dioscorea rotundata var. Dente were 62.4, 63.5, 66.8, 67.3 and 69.8 days, respectively and those of the male were 23.8, 25.3, 29.6, 30.2 and 33.5 days, respectively. Generally, the adult female lived longer than the adult male. The citrus mealybug was found to prefer D. rotundata var. Pona to the rest of the varieties because it developed faster and laid more eggs (497.0 eggs) on it. The least number of eggs (257.0 eggs) was laid on Dioscorea rotundata var. Dente and the mealybug development on it was the slowest. It should therefore be the preferred yam for long-term storage. Six chemicals were evaluated for their effect on the third instar and adult P. citri in both the laboratory and in improved yam barn storage conditions. In the laboratory, the topical method was used and in the barns, yams were sprayed with a small hand-held sprayer. In the bioassay test, observations on mortality were recorded at 12, 24 and 48 h and subjected to Probit analysis to obtain LD50 and LD90 values. It was observed that in both stages of the insect pest, the LD50 and LD90 decreased with exposure period. At the same exposure period, the lethal dosage for the third instar was lower than that of the adult insect. In all the experiments, cypermethrin recorded the lowest LD50 and LD90 values for both the third instar and adult stages with key soap iii solution recording the highest LD50 and LD90 values. In the improved yam barns 0.05 % cypermethrin, 0.07 % imidacloprid, 1.0 % groundnut oil emulsion, 1.2 %, soyabean oil emulsion, 1.9 % sunlight dishwashing detergent, 2.5 % key soap solution as well as water (control) were sprayed four times (seven days apart) onto the mealybug infested yams. The results showed that a second application of cypermethrin, imidacloprid and groundnut oil to the yams caused over 95 % mortality and was significantly (P < 0.05) higher than mortality caused by soyabean oil, sunlight detergent and key soap solution. Therefore, for rapid control of mealybug infestation of yam setts in storage, cypermethrin is recommended and it should be applied at the concentration of 0.049 %. However, the following chemicals, groundnut oil emulsion 0.963 %, soyabean oil emulsion 1.231 %, sunlight dishwashing detergent 1.948 % and key soap solution 2.475 % could be used to effectively manage P. citri on ware yam.

Source: KNUST
Biology of xanthodes graellsii (Feisth) (Lepidoptera: Noctuidae)

The biology of Xanthodes graellsii (Feisth) was studied in the laboratory and the field. The number of larval instars varied from 5 to 6 but developmental period of X. graellsii (from egg to adult stage) reared in the laboratory was longer than those reared in the field. The sex of the pupa of X. graellsli can be determined by the position of genital pore on the abdomen. In the female the genital pore occurs ventrally on the 8th abdominal segment whilst in the male it is located between 8th and 9th segments. Studies carried out on the nocturnal activities of X. graellsii revealed that adult emergence generally occurs between 1800 and 0600 and it is unimodal in distribution. The major peak for both sexes occurred after midnight. Feeding activity of the moth began at 2000 hr and ceased at 0500 hr; two peaks of feeding activity were observed. The major peak for both sexes occurred before midnight. Copulation occurred between 1900 and 0400 hr. Oviposition in female X. graellsii started at 1900 hr with a major peak between 1900 and 2000 hr. Two smaller peaks were observed between 2100 and 0300; 0400 and 0500. The flight activity was determined with an insect suction trap. The combined catch for both sexes demonstrated a bimodal distribution with the major peak occurring after midnight. Female moths were more active around midnight while male predominated in the post-midnight periods. Using the presence of spermatophore in the female bursa copulatrix as a sign of successful mating, it was observed that 2-day old male and 3-day- old female copulated successfully. Maximum mating occurred when one-day-old male was allowed to mate 3-day-old female moths. Both male and female moths copulated once per night, however repeated matings occurred in both sexes during their life time. Three insecticides were screened for their effectiveness in controlling X. graellsii attacking okro. Chlorpyrifos (48% EC) at 500 ml per acre applied at fortnightly interval gave the most effective protection to okro leaves than the other insecticides. Chlorpyrifos sprayed plants also provided the highest fruit yield followed by B. thuringiensis. Residual effectiveness of the three insecticides to the 3rd, 4th and 5th instar larvae of X. graellsii was evaluated by comparing percent mortality of larvae fed on treated leaves 1, 4, 9 and 14 days after insecticide application. Chlorpyrifos was found to have the highest residual effect against the three larval instars of X. graellsii. It was followed by B. thuringiensis. Irrespective of the insecticide used, it was observed that larval mortality decreased with increase in interval after insecticide application in the field. Preliminary studies carried on the effect of planting date on the incidence of x. graensii showed that egg and Larval infestation of okro plants started as early as 4 weeks after emergence for different planting dates. It was also observed that adjusting planting dates could contribute to the reduction of egg and larval population of X. graellsii

Source: KNUST
Biomass distribution and habitat use by forest elephants (Loxodonta africana cyclotis), Bongos (Tragelaphus eurycerus eurycerus) and Duikers (Cephaloplius spp.) in the Kakum Conservation Area

Elephants, bongos and duikers use the same patches of forest but previous studies have focused on elephants with little or no recent information on the status of bongos and duikers in Kakum Conservation Area. The objectives therefore were to estimate the number of elephants, bongos and duikers and identify the factors that underlined the distribution and use of the habitat by elephant and bongo. The size structure and biomass of the elephant population was also examined. After a reconnaissance, the study area was stratified into three (high, medium and low) density strata. By dung counts in the wet and dry seasons, the population size and biomass of elephants, bongos and duikers (Maxwell, Black and Yellow-backed) were estimated. Camera traps were also used to survey the bongo population. The elephant population size was estimated at 217 with confidence interval of 136-336. This estimate is close to an estimate obtained from a previous genetic survey of the population, when the dung data was analyzed using a model that relates the number of dung piles on the forest floor to rainfall in the two months preceding the survey. Fewer bongo droppings (<7) were recorded in each season during the dung count. Bongo photographs were not obtained through the camera traps and an estimate of bongo numbers could not be made. But through inferences from the dung count, the camera traps results and from a predicted camera trapping success, a conservative density estimate of 0.10 bongos/sq km in the high density zone is presented. The bongo population was discrete and isolated. Maxwell and black duikers densities were estimated at 9.61 and 2.20 sq/km respectively. No Yellow-backed duiker dropping was seen in the dung count. All elephants irrespective of age group were potential crop raiders. There was no marked difference when the dung boli circumference data of the elephant population in the park and their crop raiding counterparts were compared. Sub-adult elephants made the highest contribution to the dung boli records and dominated the estimated biomass. Elephant abundance and distribution was influenced by gaps in the forest canopy and fruiting tree spots. But there was a threshold of fruit abundance (approx. 2.80 fruiting tree spots/km) beyond which elephant dependence declined. A weak relationship exists in the sharing of food resources between elephants and bongos. It is suggested that there is no strong competition between the two species at their current densities. The park staffs have always said that poachers are less active in the wet season because they would be tending their farms but their assertion was not supported by the study, so anti-poaching efforts must be intensified in the wet season. Farmers also maintained that killing elephants will keep them off the crop fields but illegally killed elephants in the study area within three months to the dry season survey did not significantly influence the distribution of the elephants.

Source: KNUST
Biology of scrobipalpa blapsigona meyrick (lepidoptera: gelechiidae), a “bud worm” pest of eggplant

Studies were conducted in the field to determine the most susceptible of four cultivars (Black Beauty, Obolobo, Amantin and Aworoworo) of eggplant to attack by Scrobipalpa blapsigona Meyrick (Lepidoptera: Gelechiidae). The most susceptible cultivar, Aworoworo, was used to study the population dynamics of the moth in relation to temperature and rainfall. Other parameters studied were life cycle, fecundity and longevity of the moth. Chaetotaxy of the larvae of S. blapsigona was also investigated and setal maps drawn to help in the identification of the insect. There was negative correlation between temperature and population level of S. blapsigona but this was not significant. There was however, significant negative correlation between rainfall and population level. The population increased during dry or low rainfall periods while the reverse occurred during high rainfall regimes. Total developmental period was about 30 days. Five larval instar stages occurred during the development of S. blapsigona. Growth ratio of head capsule widths decreased at subsequent moults indicating a departure from Dyar’s law. Oviposition period was 13 days during which period the female laid 128 eggs. Longevity of the moths was influenced by sex and mating. Generally the female moth lived longer than the male. Mated female and male moths lived significantly shorter than the unmated.

Source: KNUST
Bioremediation of Hydrocarbon Contaminated Soil - A Case Study at Newmont Ghana Gold Limited – Ahafo Kenyasi

The study investigated the degradation rate of hydrocarbon contaminated soil using indigenous micro-organism. Contaminated soil containing oil and grease level and total petroleum hydrocarbon levels (mg/kg) of 3.43 x 104and 2.15x 104 respectively was bioremediated by blending 2Kg of the hydrocarbon contaminated soil with portions of compost, topsoil and fertilizer (fertilizer). The soil was inoculated with the above mentioned nitrogen sources and monitored for a period of seven(7) weeks until significant degradation occurred for the compost and topsoil hydrocarbon contaminated soil blend and eight(8) weeks for the fertilizer-hydrocarbon contaminated soil blend by which time there had been significant degradation. Specific portions of compost, topsoil and fertilizer were mixed with the hydrocarbon contaminated soil to achieve 0.2%, 0.8%1.4%, and 2.0% nitrogen levels within the various blends. The samples were placed under wooden structure covered with polythene sheets. The experiment was replicated three times in randomized complete block design. Each block contained 13 different treatments with one Control sample. At the end of the experiment, the concentrations of most of the selected treatments were reduced by up to 95% degradation. Oil and grease and Total petroleum hydrocarbons (TPH) recorded 8.09 and 8.27 % degradation respectively in the control experiments. Microbial activities were shown to correlate with the reduction in hydrocarbon contents of the soil. Statistically (p<0.05), there were significant differences in all the treatments within the compost, topsoil and fertilizer hydrocarbon contaminated soil blends. Soil analyses shows that augmenting the nitrogen levels in the various treatments have potentials to ameliorate hydrocarbon levels with increases in microbial numbers. Among all the blends, the nitrogen levels 0.2% , 0.8% , 1.4% and 2.0% of the compost gave the best performance on the hydrocarbon degradation.

Source: KNUST