Adejumobi M A, Awe G O, Abegunrin T P, Oyetunji O M, Kareem T S
Department of Agricultural Engineering, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria.
Department of Crop, Soil and Environmental Sciences, Faculty of Agricultural Sciences, Ekiti State University, Ado Ekiti, Ekiti State, Nigeria.
Environ Monit Assess. 2016 Dec;188(12):696. doi: 10.1007/s10661-016-5628-1. Epub 2016 Nov 28.
Irrigated agriculture is one of the significant contributors to the food security of the millennium development goals (MDGs); however, the modification of soil matrix by irrigation could alter the overall soil health due to changes in soil properties and processes. The objective of the study was to evaluate the effect of irrigation on soil quality status of the Ikere center pivot irrigation project site in Oyo State, southwest Nigeria. Disturbed soil samples were collected from 0 to 30, 30 to 60, and 60 to 90-cm layers from four different sites in three replicates, within the project location for the determination of soil bio-chemical properties. The average values of sodium adsorption ratio (SAR) < 13, electrical conductivity (EC) <4 μS/cm, and pH < 8.5 showed that the soil condition is normal in relation to salinity and sodicity hazards. The effective cation exchange capacity (ECEC), soil organic matter (SOM), total nitrogen (TN), and calcium ion (Ca) concentrations were low while the available phosphorus (P) was moderate. The principal component analysis showed EC, ECEC, SAR, SOM, and TN as the minimum data set (MDS) for monitoring and assessing the soil quality status of this irrigation field. In terms of bio-chemical properties, the soil quality index (SQI) of the field was average (about 0.543) while the sampling locations were ranked as site 2 > site 4 > site 3 > site 1 in terms of SQI. The results of this study are designated as baseline for future evaluation of soil quality status of this irrigation field and further studies should incorporate soil physical and more biological properties when considering overall soil quality status.
灌溉农业是千年发展目标中粮食安全的重要贡献因素之一；然而，灌溉对土壤基质的改变可能会因土壤性质和过程的变化而改变土壤整体健康状况。本研究的目的是评估灌溉对尼日利亚西南部奥约州伊凯雷中心支轴灌溉项目场地土壤质量状况的影响。在项目所在地内，从四个不同地点的0至30厘米、30至60厘米和60至90厘米土层采集扰动土样，共采集三份重复样本，用于测定土壤生化性质。钠吸附比（SAR）<13、电导率（EC）<4μS/cm和pH<8.5的平均值表明，土壤在盐分和碱化危害方面状况正常。有效阳离子交换容量（ECEC）、土壤有机质（SOM）、总氮（TN）和钙离子（Ca）浓度较低，而有效磷（P）含量适中。主成分分析表明，EC、ECEC、SAR、SOM和TN是监测和评估该灌溉田土壤质量状况的最小数据集（MDS）。就生化性质而言，该田地的土壤质量指数（SQI）为中等（约0.543），而就SQI而言，采样地点的排名为2号地点>4号地点>3号地点>1号地点。本研究结果被指定为该灌溉田土壤质量状况未来评估的基线，在考虑土壤整体质量状况时，进一步的研究应纳入土壤物理性质和更多生物性质。
