便携式激光诱导击穿光谱仪测定土壤中重金属

Determination of Heavy Metals in Soil by Portable Laser-induced Breakdown Spectroscopy

土壤重金属污染对农作物生长和人体健康都有严重危害,现场快速检测对土壤重金属污染调查、应急监测具有重要意义。采用自主研发的土壤重金属激光诱导击穿光谱现场快速检测仪对矿区周边土壤进行现场检测分析,以835个不同基质土壤的光谱数据建立定标数据库,通过支持向量机建立回归模型对土壤重金属元素含量进行定量反演。现场检测获取的全波段光谱波动在15%以内,Cd、Cr、Cu、Ni、Pb和Zn等6种元素光谱强度相对标准偏差平均值为6.31%。将检测结果与实验室电感耦合等离子体质谱法分析对比,6种元素的皮尔逊相关系数r在0.8501~0.9829,检测结果80%以上处于±30%相对误差区间分布。对比结果表明自主研发的土壤重金属激光诱导击穿光谱现场检测仪可以满足现场快速检测需求。

Heavy metals in soil are dangerous to crop growth and human health,and on-site rapid detection is of great significance for heavy metal investigation and emergency monitoring in soil.The self-developed soil heavy metal on-site rapid detection instrument,which based on laser induced breakdown spectroscopy technology,was used to conduct on-site detection and analysis of the surrounding soil in the mining area.A calibration database was established based on the spectral data of 835 different matrix reference soils,and regression models were established using support vector machine to quantitatively invert the content of heavy metal elements in soil.The full spectral fluctuation obtained on-site detection was within 15%,and the average relative standard deviation of spectral intensity of six elements,including Cd,Cr,Cu,Ni,Pb and Zn,was 6.31%.Compared the detection results with laboratory inductively coupled plasma mass spectrometry analysis,the pearson correlation coefficients(r)of six elements ranged from 0.8501 to 0.9829,and over 80%of the detection results were distributed within the±30%relative error range.The comparative results indicated that the self-developed soil heavy metal detector could meet the needs of rapid on-site detection.