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This paper seeks to examine the concentration of selected heavy metals (Cr, Pb, Cd, and Ni) in oil‐polluted soils of two communities in Warri, Delta state, Nigeria.

Soil auger samples were collected at a depth of 0‐15 cm from four sites. Two soil samples were collected from two sites observed to have had oil spills and also two samples from two sites without oil spillage. The soil samples were analysed using the UNICAM 969 Atomic Absorption Spectrophotometer to determine the level of concentration of the heavy metals in these sites. Their levels in the oil‐spilled sites are compared with those of the control sites and also with the European community standards.

The results obtained from this study reveal that the concentration of the heavy metals considered were higher in the oil‐spilled sites relative to the control sites. Similarly, when compared with the European community standards, the concentration is said to be quite significant.

The results indicate that the operations of the oil industry in the study area have not been sufficiently accompanied by adequate environmental protection. To safeguard agricultural land in the area and hence human health, there is an urgent need for government to address the incidence of oil spills in this area.

This paper provides information on the contribution of the oil industry in heavy metals contamination in the Niger‐Delta area of Nigeria.

IN the following notes the phenomenon of ground looping (which may be defined as an uncontrollable fast turn on the ground) is briefly analysed by semi‐technical methods. The analysis has been restricted to a condition which in the opinion of experienced pilots causes trouble most frequently: namely, a landing with dead stick, when there is no slipstream available to make the rudder more effective. The equations of lateral motion for an aeroplane in contact with the ground have been written clown as an introduction to more thorough study. Finally, certain tentative conclusions have been drawn for application in aeroplane design with a view to eliminating or at least reducing ground loop tendencies.

This paper aims to present the Igbo management philosophy as having the potential to bring about success in Africa and propose a framework that comprises a set of values and three key institutions: the marketplace, the family and the apprenticeship system. The paper shows that effective leaders are servant-leaders who sacrifice for others.

This paper relied on earlier and contemporary peer-reviewed, news media and books. These materials offered insight into what Igbos believed, how they behaved and how they historically organized their lives. Materials authored by both African and non-African authors were considered.

The researcher concluded that Igbos developed a management system based on a philosophy that is African, which is different from the Western system. A framework for the Igbo management philosophy is derived from complex interactions of values and institutions in Igbo societies. The researcher finds that a set of values, particularly, the value of sacrifice, is crucial for ensuring effective business leadership.

Western influence on management has persisted. However, with the economic rise of China, Asian philosophical thought has taken a more center stage in academic management scholarship. Even though human civilization occurred in Africa, it is perplexing that African management systems are not mainstream. There has been research on indigenous African systems and African management philosophy in general. Previous scholarship has also explored the Igbo culture as a whole and their apprenticeship system; however, to the best of the author’s knowledge, this is the first time a framework for an Igbo management philosophy is proposed.

Aims to focus on air pollution as one of the environmental problems that tends to improve at higher income levels.Design/methodology/approach – The paper provides a combination of narrative with argument and analysis.Findings – Between the early 1970s and the mid‐1980s, air pollution in Japan, in particular that caused by sulfur dioxide (SO₂), was reduced to a remarkable degree. This reduction resulted from responses to mounting civil protest: governmental regulation policy on the one hand, and innovation of abatement technology and energy efficiency on the other. In large Southeast Asian cities, despite rapid economic growth, air pollution is less severe than it was in Japan in the early 1970s. This is because both government and industry in Southeast Asia took early initiatives to prevent environmental degradation, learning from the experiences of developed countries.Originality/value – The conclusions drawn help in understanding the prerequisites for reducing CO₂ emissions. If developed countries actually succeed in creating abatement technology for CO₂, this will surely affect the development policy in developing countries.

Vehicular road traffic may represent an important soil and plant contamination source. In this context, the concentration of heavy metals (Cd, Pb, As, Sb, Ni, Cu, Fe, Al, Mn and Zn) and macronutrients (Ca, Mg, K and P) was evaluated in yerba mate (Ilex paraguariensis St. Hil.) cultivations and in soils adjacent to highways.

The investigated yerba mate cultivations were located in southern Brazil. Plant tissue (young and old leaves and branches) and soil (0–10 cm) samples were collected at five distances from the highway (0–10, 10–20, 20–30, 30–40 and 40–50 m). Plant tissue was analyzed with and without washing to evaluate contributions from particulate deposition.

Although increases in soil pseudo-total concentrations of Cd, Cu, Ni, Zn, Fe, Mn, Ca and Mg were observed only at the Erechim site, geoaccumulation indices and enrichment factors (EFs) did not indicate any heavy metal pollution. These results indicate the existence of natural variation in soil. Cadmium was more concentrated in branches than in leaves, while the opposite was observed for Pb. High levels of Mn and Al were found in foliar tissue. In summary, highway proximity did not lead to heavy metal contamination of yerba mate under the evaluated conditions.

This research explores the possibility of heavy metal pollution in plantations of yerba mate adjacent to highways and indicates natural concentrations of toxic elements that exceed current legislation, which was an important discovery regarding the yerba mate production chain.