科研之友
微信
新浪微博
Facebook
分享链接
摘要
The study investigates the bioavailability of selenium (Se) in potentially Se-enriched soils. A total of 64 paired samples of rice and the corresponding root soils were collected from Lujiang County, Anhui Province, China. A linear regression was used to study the parameters that are best related to the bioavailability of Se, including physical and chemical properties, nutrient abundances, Se concentrations, distribution of Se in soil samples, and Se concentrations in the associated rice. The results indicate that the rice the study area contains 0.037-0.120 mg/kg (Se), whereas the associated soil samples contains 0.260-1.177 mg/kg (Se). Se in the soil samples was mainly distributed between humic acid bound phases (15.5%-31.5%), strongly bound organic phases (12.5%-38.6%), and residual phases (8.1%-68.5%). Increasing abundance of effective sulfur (S) and phosphorus (P) positively correlated with the concentrations of Se in rice as a result of an increase in the abundance of Se in strongly bound organic phases, humic acid bound organic phases, and the extractable concentrations of Se in soil. In contrasts, increases cation exchange capacity (CEC) and the concentrations of available K, Fe and Mn in soil inhibited the uptake of Se by rice as a result of the reduction in the concentration of available Se in soil, primarily as this Se was present in soils in the form of humic acid bound Se, strongly bound organic phase Se, extractable Se, and water-soluble Se. Soil Se concentrations have a strong positive correlation with rice Se concentrations (R=0.616, P<0.01). In addition, the concentration ratios of non-residual phase Se and organic matter (NRE-Se/OM) also strongly positively correlate with rice Se concentrations (R=0.774, P<0.01).This study used a multiple stepwise lineal logarithmic regression approach combined with NRE-Se/OM values, effective S and Fe soil concentration data, and the total Mn soil concentration data to generate a model for Se uptake by rice, with some 76.0% of the variance in the model being explained by variations in these values. This means that soil NRE-Se/OM, effective S and Fe, and the total Mn values can be used to effectively evaluate soil Se bioavailability. ? 2018, Editorial Board, Research of Environmental Sciences. All right reserved.
- 单位
