Nitrogen and weed management in transplanted tomato in the Nigerian forest-savanna transition zone

Weed infestation and inherent low soil fertility are among primary reasons for low yields of tomato in Nigeria. Field trials were carried out during the wet season of 2015 and 2016 to evaluate yield response of tomato to nitrogen (N) application and weed control methods in the forest-savanna transition zone of Abeokuta, Nigeria. Positive relationship exists between growth of weed species and increase in N application. Across the years of study, increase in N up to 90 kg/ha increased weed density by 11–25%, however, the increased N gave the transplanted tomato competitive advantage and thus enhanced weed smothering. Pre-transplant application of butachlor (50% w/v) or probaben® (metolachlor 20% w/v+prometryn 20% w/v) each at 2.0 kg a.i/ha followed by supplementary hoe weeding at 6 weeks after transplanting (WAT) significantly reduced weed density by at least 15% and increased fruit yield of tomato by at least 32%, compared to use of the pre-transplant herbicides alone, across both years of study. The greatest tomato fruit yield of 12.2 t/ha was obtained with pre-transplant application of butachlor at 2.0 kg a.i/ha followed by supplementary hoe weeding at 6 WAT, averaged for both years. In general, this study suggests that increased application of N up to 90 kg/ha, and complementary weed control by pre-transplant herbicide and hoe weeding at 6 WAT would improve yield of tomato in the forestsavanna transition zone of Nigeria

Environmental quality and economic growth in Nigeria: A fractional cointegration analysis

The paper investigates the relationship between environmental quality and economic growth in Nigeria using a fractional cointegration analysis over the period 1970-2011. It seeks to examine the effect of growth on environmental performance by controlling for the role of institutional quality, trade openness and population density. The paper found that early stages of development in Nigeria accentuate the level of environmental degradation. It also finds that weak institutions and unrestricted trade openness increase the extent of environmental degradation due to environmental dumping. Finally, the paper shows that a larger population density enhances the promptness of environmental abatement measures and consciousness for cleaner environment. The study, however, failed to attain a reasonable turning point and hence a non-existence of EKC in Nigeria. The paper recommends the need to restrict the importation of emission intensive products, check the activities of multi-nationals which invest in producing high CO2 emitting goods in LDCs and exports to home countries. Finally, there is need to strengthen institutional quality to ensure adoption of clean technologies as income rises

Central Nervous System Depressant Properties of Treculia africana Decne

The study was carried out to investigate the central nervous system activity of Treculia africana. The central nervous system depressant properties of Treculia africana were determined using: Novelty –Induced Rearing and Grooming, Locomotor activity, Ketamine-induced sleeping time and effect on rectal body temperature. The crude extract produced decrease in rearing, grooming and locomotor activity. It also potentiated ketamineinduced sleeping time and produced hypothermic effect in mice. The crude extract possessed sedative effect, which may be through increase in the activity of GABA in the brain

FOREIGN DIRECT INVESTMENT AND ECONOMIC GROWTH IN ECOWAS: A SYSTEM-GMM APPROACH

The paper investigates the relationship between foreign direct investment and economic growth in ECOWAS using the System-GMM panel estimation technique covering the period 1970-2011.The study adopted System-GMM in order to overcome the weaknesses perceived in the empirical works of earlier studies; majority of these studies failed to control for the presumed challenges of endogeneity inherent in the FDI-Growth argument. The study likewise interacted human capital and institutions indicators with other explanatory variables in explaining the variability of FDI. The results of the System-GMM appears contrary to earlier studies, as the contribution of FDI was insignificant and impacts negatively on growth in ECOWAS despite the controlling for the role of human capital and quality of institutions in the model. Following this outcome, policy makers in developing Africa needs to exercise cautions in adopting the recommendation from earlier studies; most of which advocates more openness, human capital development and the strengthening of institutions. This might not be completely helpful considering the pattern of FDI inflow into ECOWAS, which is absolutely resourceseeking. There is need to curtail excessive openness in the extractive industries, encouraging more manufacturing FDI and domestic investment of repatriated capital by ensuring more economic stability and raising domestic interest rate

The Role of Services Trade in Economic Development

This paper is an attempt to investigate the impact of services trade on economic development of Sub-Sahara African (SSA) countries. Our analysis is based on a panel data framework over the period 1990 to 2010 covering thirty-three countries. The paper employs the endogenous growth model to examine the nonlinearities associated with services exports and services imports in the economic development process of SSA countries under consideration. The trade data was disaggregated into travel, transport and other services. The panel data constructed was estimated using ordinary pooled, fixed effects and random effects model techniques and the efficient model was selected based on the Hausman test. The paper finds that both services exports and services imports enhance economic development process. The study also indicates that labour and capital play an important role in the SSA economies

LINEAR PROGRAMMING APPROACH TO MODELING FOUNDRY CUPOLA FURNACE CHARGE

In order to control the specifications of the cast iron produced by the cupola furnace, it is necessary to estimate the proportions of the contents of the furnace charge. Traditionally, knowing the percentage of elements present in each constituent of charge and the loss or gain of each element, the final analysis of cast iron can be estimated by trial and error approach - a common approach in most Nigerian foundry workshops. This study presents a programming model technique used to obtain the optimum cupola furnace charge. The objective function was to minimize total cost of raw material and processing costs. The model was developed and implemented using the hypothetical process data of a Foundry workshop. The model was analysed using MATLAB Software Version 7.0. The results obtained using the model is significantly superior to the conventional trial and error approach. It is faster and brings about satisfying a lot of requests at the most minimal expense.&nbsp

Tree Slenderness Coefficient and Percent Canopy Cover in Oban Group Forest, Nigeria

Oban Forest health was assessed using tree slenderness coefficient (SC) and percent canopy cover as indicators. Systematic sampling technique was adopted for plot locations in Aking, Ekang, Erokut and Ekuri sites within the forest. Four transects of 2 km-long situated 600 m apart were established in each site. Five 0.25ha-plot were then alternately laid along each transect at 400 m intervals. A total of 20 plots per site, and 80 plots in all were used. Tree heights, Dbh and crown diameter were measured on trees with Dbh≥10cm to compute SC and percent canopy cover (%CC). Trees were classified based on their SC as high (SC>80), moderate (SC: 70-80 and low (SC<70). Data were analyzed using descriptive statistics and correlation analysis. There were 36, 49 and 67 trees/ha with high, moderate and low SC, respectively for the pooled data with 56.5% CC. On site basis, Aking had 145 trees/ha, and of these, 44, 45 and 56 trees/ha had high, moderate and low SC, respectively. Ekang had 147 trees/ha, and of these, there were 45, 50 and 52 trees/ha with high, moderate and low SC, respectively.  Erokut had the least 143 trees/ha, and of these, 37, 50 and 56 trees/ha were with high, moderate and low SC, respectively with 49.95% CC. Ekuri had the highest 173 trees/ha, and of these, 62, 43 and 68 trees/ha had high, moderate and low SC, respectively with 59.8% CC. There were negative correlations between SC and other tree growth parameters except tree height (r = 0.07). About 24% of the trees had high SC, which implies high susceptibility to wind-induced damage, with highest trees/ha in this category found in Ekuri site due to high stand density. This may cause competitions among trees, thereby limiting trees development. Hence, appropriate silvicultural treatment such as low-impact logging is recommended. Keywords: Stand stability, slenderness ratio, crown dimension, susceptibility, wind-thro

Challenges of Slum Upgrading in Port Harcourt, River State, Nigeria

Environmental decay in a city is essentially caused by rapid urbanization and the mismatch in the provision and maintenance of housing and infrastructure. This study examined challenges of slum upgrading in Port Harcourt, Nigeria. The study aims to examine slum areas and their living conditions, and finding out the most critical and problematic zone of the slums Two sources (primary and secondary) of data were utilized in the study: The study population for this study was the residents of Diobu and Waterside in Port Harcourt, River State. Both descriptive and inferential statistics were used to analyse the data appropriately. Findings established that 11.3% acquired primary education, 29.0% have secondary education, and 14.0% had NCE, 21.0% had both HND and degree and 3.8% had no formal education. Findings showed that 31.7% of the residents were owners of the building while 68.2% were living in rented apartments. Findings revealed that 40.9% of the respondents have bad drainage system which would lead to dirty environment and 6.5% having very good drainage system. The study concluded that majority of building structures in the study area are old that existed for decades without maintenance and the surrounding environment very poor due to neglect

INFLUENCE OF ORGANIC MANURE AND WOOD ASH ON THE ABUNDANCE OF SOIL MICROORGANISMS, ORGANIC CARBON AND GRAIN YIELD OF SOYBEAN (GLYCINE MAX L. MERRILL) IN ACID SOIL

Organic production methods which include the exclusion of chemical approach of soil amendment have been observed to improve plant growth and preserve the soil health and biodiversity of production environment. A study was conducted at the Federal University of Agriculture, Abeokuta, to examine the influence of organic manure and wood ash on the abundance of soil microorganisms, organic carbon and yield of soybean in acid soil. The study consisted of three rates of wood ash (0, 2.5 and 5.0 t ha-1) and three rates of cow dung (0, 5.0 and 10.0 t ha-1) arranged in completely randomized design, replicated three times. Soybean variety TGX 1485 – ID was sown into 5 kg. The results showed that wood ash application at 5.0 t ha-1 significantly increased the soil pH (6.6), organic carbon (7.48) and soil microbial population (110 × 104 cfu g-1) compared to lower rate of 2.5 t ha-1 and control, which resulted in highest number of pods (7.7) and grain yield (14.2 g per plant) at harvest. Cow dung treatment of 10 t ha-1 significantly had highest soil organic carbon (7.39%) at 8 WAP and soil microbial population (21.1 and 91.4 × 104 cfu g-1) at 4 and 8 WAP respectively. These findings indicate that application of wood ash may be an acceptable alternative liming agent to the inorganic soil amendment and higher soybean productivity.   &nbsp