果蔗地土壤中铬、铜和锌含量特征研究

Study on Content Characteristics of Cr,Cu and Zn in Chewing Cane Soil

利用微波消解-火焰原子吸收光谱法测定果蔗地土壤中的铬、铜和锌含量,验证检测方法的检出限、准确度与精密度,并对果蔗地土壤中Cr、Cu和Zn的污染状况进行评价。结果表明:果蔗地土壤中Cr的含量为22.8~100.8 mg·kg^(-1),平均值为54.5mg·kg^(-1);Cu的含量为22.6~41.2 mg·kg^(-1),平均值为29.8 mg·kg^(-1);Zn的含量为48.6~184.6 mg·kg^(-1),平均值为107.4 mg·kg^(-1)。Cr和Zn元素在土壤中变异系数较大,而Cu元素在土壤中变异系数较小。频数分布图显示,土壤中Cr不符合正态分布,Cr含量大多在27.0~86.0 mg·kg^(-1),土壤中Cu和Zn含量基本符合正态分布,Cu含量大多在23.0~39.0 mg·kg^(-1),Zn含量大多在60.0~170.0 mg·kg^(-1)。以土壤环境质量标准中的二级标准值为评价依据,果蔗地土壤Cr、Cu和Zn元素均无污染,但果蔗地土壤Zn含量最大污染指数为0.92,该土壤已接近轻度污染的边缘,需要引起管理者和生产者的注意。

Microwave digestion-flame atomic absorption spectrometry method was used to determine the concentrations of Cr,Cu and Zn in chewing cane soil. The detection limitation,accuracy and precision of the method were validated,and the characteristics of Cr,Cu and Zn pollution in chewing cane soil were assessed. The results showed that the range of Cr concentration in soils was 22. 8- 100. 8 mg·kg^-1,the average concentration is 54. 5mg·kg^-1,the range of Cu concentration in soils was between 22. 6- 41. 2 mg·kg^-1,the average concentration was 29. 8 mg·kg^-1,and the range of Zn concentration in soils was between 48. 6- 184. 6 mg·kg^-1,the average concentration was 107. 4 mg·kg^-1. The coefficient of variation of Cr and Zn concentration in soils was large,whereas that of Cu concentration was small.Frequency distribution graphics of Cr,Cu and Zn showed that the concentration of Cr isn＇t according with the normal distribution,but that of Cu and Zn was according with the normal distribution,and the concentration are mostly 27. 0- 86. 0 mg·kg^-1for Cr,23. 0- 39. 0 mg·kg^-1for Cu,and 60. 0- 170. 0 mg·kg^-1for Zn. Based on the environmental quality standard of soils,Cr,Cu and Zn concentration in soil was at clean level,But Zn content maximum pollution index in soil was 0. 92,which was close to the edge of the light pollution,so it should be attracted the attention of the administrators and producers.