期刊名称：IMPACT : International Journal of Research in Applied, Natural and Social Sciences
印刷版ISSN：2347-4580
电子版ISSN：2321-8851
出版年度：2014
期号：1407
页码：273-288
出版社：IMPACT Journals
摘要：This study was undertaken to evaluate the effect of cultivation and fallow on the Organic Carbon (OC), Total Nitrogen (TN), and available phosphorous (P) concentration in aggregate fractions of four soils. The four soils used for the study are; Entisol, Ultisol and two Inceptisols, all collected from four different locations in Nsukka area of Southeastern, Nigeria. The land use types considered were Fallow and Cultivated. The soils collected from 0-25 cm depth were separated into five aggregate fractions, 5-2 mm, 2-1mm, 1-0.5 mm, 0.5-0.25 mm and Ultisol at Nsukka (UNsk) > Inceptisol at Eha-Amufu (IEh) > Inceptisol at Ikem (Iik). The total N concentration in dry sieved samples of ENsk was higher compared with those of similar fractions of UNsk, IEh and Iik, while wet sieved samples showed no consistence in the decrease of the TN concentration of the aggregate sizes. The total N concentration in both dry and wet sieved samples of UNsk increased progressively as the aggregate sizes decreased, while the highest TN in IEh was obtained in 0.5-0.25 mm aggregate size of dry sieved of fallow soil and wet sieved of cultivated soil. The lowest concentrations of TN in Iik was obtained in 1-0.5mm aggregate size for the dry sieved samples of fallow soil, and no particular change in the TN concentration of 1-0.5mm and 0.5-0.25mm size of cultivated soil. The wet sieved samples of the same soil showed that the highest concentration of TN was obtained in 0.5-0.25mm size in fallow soil and 17.3% decrease in
