Floodplains are agro zone for most vegetables worldwide and incidentally they are sinks for pollutants especially heavy metals. The total concentration of metals is not a good indicator of mobility/bioavailability or potential risk assessment hence more preferred elemental geochemical environment. This study is therefore aimed at investigating the geochemical environment of some potentially harmful elements in the agro zone flood plains of some rivers in Ekiti State, Southwest Nigeria. Bulked soil samples of 0-10cm, 10-20cm and 20-30cmdepth were collected at 5m, 25m and 45m perpendicular distances to the river course. Soil samples were air-dried in the dust free open laboratory, disaggregated, sieved through 2mm BS mesh and sequentially fractionated using Tessier’s method. The result shows that a large proportion of the fractions were found in the non-mobile fractions bound to organic matter (F4)and residual (F5), implying that the metals may not be readily available for plant uptake. The mobility factor for the metals at Irintan floodplain, (Ogbese) Omi-Eye floodplain (Erio) and Egbigbu floodplain (Ayetoro),were respectively in the order Pb>Zn>Cr>Cu>Fe>Cd, Cd>Fe>Cu>Zn>Pb>Cr and Cd>Zn>Cr>Fe>Cu>Pb. This suggests that cadmium has the highest mobility factor at both Omi-Eye and Egbigbu floodplains than other metals. This portends danger as the metal is known to be potentially toxic to ecosystem. It is hereby recommended to regulatory authorities to carry out a more detailed assessment of the floodplains for potentially toxic metals contamination to forestall transfer to human through plant uptake.

Crop productivity depends to a large extent on the physicochemical properties of soil on which it is grown because the later has direct relationship to the nutrient requirements and uptake of crops. Floodplains are notable for seasonal utilization to produce crops especially fruits and vegetables for our teeming population. However, the floodplains can be affected by rainfall/storm regime in a way that can impact nutrients availability negatively. It is on this premise that this research was conducted to investigate physicochemical properties of some floodplains in Ekiti State, Nigeria to ascertain their suitability for crop production. Soil samples (0-30 cm) were collected at 5 m, 25 m and 45 m perpendicular distance to each of the three river parts at upper, middle and lower portion of the river channel. The samples were air-dried, milled, sieved and subjected to physicochemical analyses using standard methods. The ranges of the physicochemical properties are pH (5.02-7.13), electrical conductivity (34.00-571.00 μS/cm), organic matter (0.14-3.77 %), nitrogen (0.03-1.47 %), Ca2+ (0.23-4.94 cmol/kg), Mg2+ (0.15-4.64 cmol/kg), Na+ (1.20-3.62 cmol/kg), K+ (2.15-19.75 cmol/kg), Al3+ (0.41-23.02 cmol/kg), H+ (0.34-28.71 cmol/kg) and CEC (9.53-65.32 cmol/kg). In general, the floodplains are slightly acidic with low organic matter content typical of West African sub-region, sandy loam with moderate cation exchange capacity. It is recommended that the floodplains under study be treated to reduce the exchangeable sodium percentage for better crop production. The acidic soils are also recommended to be limed in order to prevent the possibility of pollutants like heavy metals from entering into the food chain. Recommendations are made to improve the soils’ physicochemical condition for increased food production.