Contributions of organic matter, clay and silt to the effective CEC of soils of different land use history

This study examined the contributions of organic matter (OM), clay and silt to the effective cation exchange capacity (ECEC) of soils of different land use history, in order to determine the influence of land use on the contributions of the various fractions to the ECEC of the soils. The land use types examined were sole cassava (C), sole pigeon pea (P), mixed cropping of cassava and pigeon pea (C + P), natural fallow land (FA) and forestland (FO). The results showed that in FA and FO, the OM fraction contributed more to the ECEC compared to the other fractions. The contribution of clay was more visible in the legume-based cropping systems, while that of silt was more pronounced in C. The average contribution of OM to ECEC was 54%, while that of silt and clay were 26% and 20%, respectively. Thus the OM fraction gave better predictions of ECEC than the particle size fractions in an Alfisol of southeastern Nigeria. The low contribution of clay to ECEC recorded in this study may be due to low activity clay dominant in the clay mineralogy of the soil

Micronutrients availability in a cleared forestland after seven years of continuous cultivation and eight years of natural fallow in an Alfisol, eastern Nigeria

Micronutrients content in a cleared forestland continuously cropped for seven years with cassava, maize, pigeon pea and their combinations and subsequently fallowed for eight years were monitored in this study in order to determine the availability of these nutrients after these years. Soil samples were collected at the end of the cultivation and fallow periods and were analysed for available zinc, copper, iron and boron in addition to available phosphorus, pH and organic matter. The results show that micronutrients content (except copper) in the various plots decreased after years of cultivation, these equally increased after the fallow period especially for available zinc. The rate of micronutrient recovery after fallow was more on the plots which had cassava as a treatment. Availability of micronutrients was affected by soil properties especially available phosphorus which had a significant (p < 0.05) negative correlation with zinc. Significant (p < 0.05) negative correlation between zinc and copper, as well as a significant (p < 0.01) positive correlation between boron and iron were obtained in this study. More research is needed in order to understand the interrelationships that exist among micronutrients in alfisol of eastern Nigeria

Assessment of the Relationship between Southern Nigerian Universities and Students on Facebook

This study set out to assess Nigerian universities and studentsrsquo relationship in the social media age using Facebook Page posts as a means to measure. This study was motivated by the fact that there have been series of protests and demonstrations in the universities in the southern, Nigeria. Three research questions were posed to guide the study. Using the content analysis, data were collected using the coding sheet as the instrument. The purposive sampling method was used to select one university each from the three zones that make up southern, Nigeria. Data were presented in table and mathematical forms. The results show that students comment on the Facebook Page posts of the universities. The study equally found out that the interaction between the students and the university management was poor. Universities used Facebook Page for promotional reasons. It was recommended that the public relations unit every university should post messages that can cause discussion through which the management would know the studentsrsquo needs and address them early enough.nbspnbs

The contibutions of soil properties to cassava yield parameters in Sub-Saharan Africa

The Collaborative Study of Cassava in Africa (COSCA) undertook cassava yield and soil fertility surveys in sub-Saharan Africa in 1991 with the objectives of obtaining average yields from farmers' fields and determining factors which could account for the yield differences across the various climate, altitude, population density and market access zones - the site selection factors considered in the study. In this analysis, the contributions of various soil properties determined from the fields were also obtained and evaluated. The cassava yield parameters considered were fresh root and shoot weight, harvest index and cassava stand density. The interaction between the site selection factors had a greater significant effect on the yield parameters than the individual factors. Whereas the effect of climate was not significant (P = 0.1), both climate x market access and population x market access interactions were highly significant (P &#61603; 0.01) on root yield. The overall mean root yield was estimated as 13.1 t/ha. It was highest in the subhumid followed by nonhumid and lowland humid zones, and least in the highland humid zone. It was significantly (P &#61603; 0.05) higher (13.6 t/ha) in the low altitude zones than in the mid (8.5 t/ha) altitude zones. The results of stepwise regression analysis showed that the total contribution of soil variables to root yield variations ranged from about 30% for the entire sub-region through 32% in the lowland and about 40% in nonhumid zones to more than 45% in the highland humid zones. The contribution of total sulphur to the total variations in root yield was consistently high in both the sub-region and across the climate zones compared to other soil variables evaluated. The overall contributions of the soil variables to shoot yield, harvest index and stand density were approximately 35%, 30% and 50%, respectively. Though the contributions of the soil properties to cassava performance confirmed that other factors are also important in cassava production, the significant roles of individual soil variables both in the sub-region and across the climate zones have been established. Keywords: cassava, soil properties, regression, subSaharan Africa> Agro-Science Vol. 6 (1) 2007: pp. 1-1