基于主成分分析的沈阳地区水稻土镉污染修复剂修复效果评估

土壤是人类赖以生存发展的重要资源，但目前我国的土壤重金属污染问题带来的威胁日益加重。为了比较不同类别的修复剂对于镉污染水稻土的修复效果，通过盆栽培养实验，研究了以含磷物质、碳酸钙、生物炭、贝壳粉以及巯基化天然矿物为主要成分的六类重金属土壤修复剂在不同的用量条件下对水稻土土壤特性、重金属镉的生物有效性及作物中重金属含量等三个方面的影响。利用主成分分析的多元统计学方法将具有较高相关性的众多评价指标在保证原始数据信息损失最少的情况下用三个综合评价指标取代，客观确定指标权重并进行综合得分排序分级。结果表明，六类修复剂均可显著降低水稻土镉的生物有效性，降低稻米中镉的含量。根据评价结果得出主要成分为碳酸钙的修复剂效果为最佳，主要成分为生物炭的修复剂与主要成分为含磷物质的修复剂次之，巯基化天然矿物的修复效果最差。

Evaluating Remediation Effects of Remediation Agents on Cadmium-Contaminated Paddy Soil in Shenyang Based on Principal Component Analysis Method

Soil is an important natural resource for human survival and development. However, the threat of soil heavy metal contamination in China is becoming increasingly serious. Six remediation agents for soil heavy metal contamination in this study, including phosphorus-containing material, calcium carbonate, biochar, shell powder and natural sulfhydryl minerals, were added to paddy soil contaminated with cadmium (Cd) at varied rates in a pot experiment to investigate their effects on soil properties, bio-availability of Cd and Cd content in crops. Three evaluation factors were selected by the method of principal component analysis (PCA), and ranked based on the comprehensive scores after determining their weights. The results showed that the six remediation agents significantly reduced the bio-availability of Cd in paddy soil and the content of Cd in rice. Thecalcium carbonate had the best remediation effects on the heavy metal contaminated soil, following by the biochar and the phosphorous-containing material, while the natural sulfhydryl mineral was presented the worst remediation effect.