响应面法优化土壤有效硒浸提条件及生物有效性研究

Optimization of soil available selenium extraction conditions and bioavailability by response surface methodology

以土壤为材料,采用KH2PO4溶液提取土壤中的有效硒。以有效硒的提取量为响应值,浸提液浓度、pH、浸提时间和液料比为自变量,建立数学模型,利用响应面法获得土壤有效硒的最佳提取条件。结果表明,土壤有效硒的最佳提取条件为浸提液浓度0.5mol/L,pH9.9,浸提时间72min,液料比27∶1,在此优化条件下有效硒提取量为0.56mg/kg,与响应面分析预测值0.53mg/kg基本相符。作物盆栽试验也表明,土壤有效硒的KH2PO4溶液浸提法可以作为评价土壤对作物有效态硒的指标。

Using soil as material, KH2PO4 solution was used to extract available selenium from soil. Taking the available selenium extraction amount as the response value, the extract concentration, pH value, extraction time and liquid sample ratio were independent variables, and the mathematical model was established. The optimal extraction conditions of soil available selenium were obtained by response surface methodology. The results showed that the optimal extraction conditions for soil available selenium were: extract concentration 0.5 mol/L, pH 9.9, extraction time 72 min, liquid sample ratio 27∶1, and the available selenium extraction amount was 0.56 mg/kg under the optimized conditions, which is basically consistent with the response surface analysis predicted value of 0.53 mg/kg. The crop pot experiment showed that the KH2PO4 solution extraction method for soil available selenium can be used as an index to evaluate the soil available for crop selenium.