【摘要】 采用盐酸-硝酸-氢氟酸-高氯酸消煮,电感耦合等离子体发射光谱仪(ICP)测定方法,并结合地统计学和GIS研究了5.12汶川地震后典型灾区土壤的Cd、Pb空间分布特征及影响因素。结果表明,研究区域土壤Cd、Pb平均含量分别为0.36±0.20 mg/kg和28.97±6.82mg/kg。Cd、Pb含量空间分布分别表现为带状和团状;Cd含量以中东部低浓度所在区域为中心,分别向北部、中西部和南部逐渐增加;Pb含量总体上从北到南、从东到西表现为先减少后增加;地震后帐篷安置点、生活垃圾堆放点、房屋倒塌点土壤Cd、Pb含量明显高于未受地震影响处;帐篷压实水田40～60cmCd含量最高,为0.46mg/kg,自然水田0～20cmCd含量最高,为0.57mg/kg;压实、自然水田各土壤剖面Pb含量均为0～20cm最高,分别为25.22、26.16mg/kg。影响因素分析结果表明:水田土壤、旱地土壤和荒地土壤中Cd含量无显著差异,水田土壤Pb含量显著高于荒地土壤;Pb含量与土壤有机质含量成极显著正相关(r=0.616),Cd含量与pH和有机质含量相关性不强;人类活动对土壤中Cd、Pb含量有一定影响,且水平方向上对Pb影响程度大于Cd,垂直方向上则相反。更多还原

【Abstract】 Using hydrochloric acid,nitric acid,hydrofluoric acid and perchloric acid digestion,ICP determination method,combined with geostatistics and GIS,this paper studied the distribution characteristics and influencing factors of Cd,Pb of the soil samples in a typical 5. 12 earthquake-stricken area named Xinhuang village as an example. The results showed that the average Cd content of the soil samples was 0. 36 ± 0. 20 mg /kg,23. 08% of which exceeded the national soil environmental quality standard Ⅱ,but didn’t exceed the standard Ⅲ. The average Pb content of the soil samples was 28. 97 ± 6. 82 mg /kg and did not exceed the national standard Ⅱ. The spatial distribution of Cd,Pb content appeared as belt-shaped and group shape respectively. Cd content took the mid-eastern part as a center,whose concentration was low,and gradually increased to north,to mid-west and to south,respectively; Pb content decreased first and increased afterward from north to south and from east to west. However,Cd,Pb contents in the soil under tent settlements after the earthquake,living garbage dumps and the housing collapse were significantly higher than the soil where were not affected by the earthquake. Cd content in the paddy field soil of 40 ～ 60 cm depth under tent settlements was the highest,which was 0. 46mg /kg,the highest was 0. 57mg /kg; in the natural paddy field soil of 0 ～ 20cm,which . Pb content in the paddy field soil of 0 ～ 20 cm depth under tent settlements and the natural paddy field soil,were 25. 22 mg /kg and 26. 16mg /kg respectively. The influencing factors indicated that: Cd content of paddy fields,dry land and wasteland had not significant difference; Pb content of paddy fields were significantly higher than that of wasteland; The correlation coefficient of organic matter content and the Pb content was 0. 616,which took a highly significant positive correlation; Cd content and pH or Cd content and organic matter content did not take significant correlation; The human activities had a certain impact on Cd,Pb content in the studied area,and the degree of influence on Pb was more significant than that on Cd in the horizontal direction,that was opposite in vertical direction.更多还原