Carbon-nitrogen dynamics in organic wastes amended-crude oil polluted wetland soil

No Abstract. Agro-Science Vol. 3(1) 2002: 20-2

Climate Change and Nigerian Soils: Vulnerability, Impact and Adaptation

This article reviewed the impact of climate change on our soils and suggested measures to combat or mitigate its negative effects on sustainable soil productivity. Climate change occurs when a situation in which a change in climate continues in one direction at a rapid rate and for an unusual long period of time. The article shows that Nigerian soils have high potential of susceptibility to the impact of climate change with adverse consequences. The vulnerability of our soils to impact of climate change is associated with among other things human factors, illiteracy, low level of technology applied in crop and animal production, type of soils and inadequate climate change policy and bills. Most Nigerian soils belong to the Ultisols, Alfisols, Inceptisols, Entisols, Vertisols order of the USDA Soil taxonomy and respond to climatic change differently depending on a lot of factors including their mineralogical classes. The mineralogy of Nigerian soils is dominated by low activity clays. The impacts of climatic change on soils could be positive or adverse and devastating. Some of the identified impacts are reduction in soil biodiversity, soil erosion, excessive soil wetness, high soil temperature, depletion of soil organic pool, increased soil acidity, change in soil consistence, desertification and general decrease in the overall quality of the soil for agricultural, engineering and other land uses. Based on our local condition and environment, mitigation and adaptation measures are presented in the paper for confronting climate change problems. These methods dwell on the following- management practices to be adopted by farmers, advocated government support programmes and policies and expected roles communities as well as individuals should play in reducing the negative impact of climate change on Nigerian soils. Generally, ensuring adequate cover, changing inputs and varieties and/or species of crops , making wide use of technologies in farming, creating incentive from government and reduction in deforestation and promotion of afforestation are some of the measures recommended. Research on carbon sequestration on continued basis is also recommended.Key words: Climate change, Nigerian soils, vulnerability, adaptation

Hydrocarbon Degradation In Poultry Droppings And Cassava Peels-Amended Typic Paleustults In Southeastern Nigeria

This greenhouse study was aimed at determining the potentials of poultry droppings (PD) and cassava peels (CP) for nutrient-enhanced biodegradation of petroleum hydrocarbon (THC) in a well drained TypicPaleustults using the THC levels and degradation duration as remediation indices. The performance of the organic amendments was compared against the performance of NPK fertilizer. The soil was contaminated withcrude oil at the rate of 50 t/ha, after which the soil amendments were applied in single and combined forms (25 t PD/ha + 25 t CP/ha, and 50 t PD/ha + 50 t CP/ha), with the control as 0 t/ha (without soil amendment). Soil samples were collected from the contaminated soils at 14, 45, 76, 131 and 201 days after the application of the amendments respectively. There were significant (P = 0.05) effects of the amendments and rates of application on the THC concentrations. A comparison of the effects of PD, CP, NKP fertilizer and PD + CP on the THC concentrations at 201 days showed decrease in the contaminant concentrations in the order: NPK fertilizer < PD < CP + PD < CP < Control. The percent THC degradation at 201 days for 50t CP and 100t CP were 23 % and 24 % respectively, while that of 50t PD and 100t PD were 34 % and 36 % respectively. For soils treated with NPK fertilizer and CP + PD, the percent THC degradation was 40 % and 41 % for 50t NPK and 100t NPK fertilizers respectively, and 26 % and 31 % for 25t CP + 25t PD and 50t CP + 50t PD respectively. The timerequired to completely degrade the THC in the soil followed the same trend. Although PD showed great potential for THC degradation, it will take less time to achieve 100 % degradation of THC in NPK fertilizeramendedsoil when compared with the other nutrient supplements

Soil moisture retention characteristics in relation to erodibility and texture of some soils of southeastern Nigeria

No Abstract Available E. Afr. Agric. For. J Vol.68(1) 2002: 17-2

Soil physical criteria for evaluating irrigation suitability of Okija upland soil of southeastern Nigeria

Suitability of upland soils of Anigbo Okija for irrigation was assessed using soil physical criteria of texture, depth, pore type, slope percent colour and soil structure for the purpose of estimating season farming and rainy season drought. Soils were classified using Soil Taxonomy and FAO/UNESCO legend. Mapping was done based on physiographic differences. Results showed two distinct soil mapping units A1 and A2 with two suitability classes: moderately suitable (S2) and marginally suitable (S3)., based on soil erosion and topographic limitations respectively. Two capability classes were consequently identified as &#61536;e and IIIe for soil mapping units A1 and A2 respectively. Soils were classified as Typic Paleudalf and correlated to FAO/UNESCO legend as Dystric Nitisol for soil mapping unit A1 and Typic Paleudult (S.T.) or Dystric Nitisol (FAO/UNESCO legend) for A2. Journal of Agriculture, Forestry and the Social Sciences Vol. 3 (2) 2005: pp.99-10