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Enyigba in southeastern Nigeria is one of the agrarian communities facing water scarcity challenges. The open cast mining activities in the region are also compounding the water problems as a result of leakage of heavy metals that pollute the limited water resources. This study is conducted to document the current state of surface water contamination by heavy metals and its impact on domestic and agricultural uses. Thirty water samples were collected from five sources at both the upstream, middle stream and downstream of each of the selected sites. The heavy metals were analysed using the standard laboratory methods. Generally, the average concentrations of As, Cd, Cu, Pb and Zn in the studied water bodies were 17.68, 4.30, 3.14, 0.05 and 35.57 mg/l, respectively, which were above the WHO permissible limit. Contamination of water above WHO permissible limits with heavy metals in the surface waters, because of open cast mining, is considered a serious threat to both domestic and agricultural usage. The need for establishment of treatment facility, periodic monitoring of heavy metal levels, recycling plants and principal technologies to monitor the mine sites are hereby recommended.

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 Typic Paleustults 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 with crude 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 time required 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 fertilizeramended soil when compared with the other nutrient supplements.

Detailed studies on the micromorphology and mineralogy of two gullied soils in Anambra State of Nigeria were carried out. Thin sections were prepared and point counting technique used in investigating the pedological features. Micromorphological analysis indicates that the S-matrix of the soil have mainly sepic and inundulic with few asepic plasmic fabric. Distribution patterns are agglomeroplasmic to porphyroskelic and granular.Clay mineralogy was determined by x-ray diffractometry and the result reveals that the soils are mostly dominated by kaolinite and quartz.Macromorphologically, the soils are very deep, well drained and coarse to medium textured with granular and medium subangular structures.The occurrence of ferriargillans in the B-horizon is a strong indication of pedotranslocation. Other contemporary processes or regrouping phenomena are pedotranslocation, pedoturbation, pedocompaction and pedotransformation of minerals. The role of clay mineralogy type in soil erosion problems is discussed.

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.

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