广宁红花油茶林土壤及植物中微量元素、重金属调查分析

A Preliminary Study on Medium Trace Element and Heavy Metals for Soil and Leaf of Camellia semiserrata

调查了广东东莞樟木头林场广宁红花油茶Camellia semiserrata 林土壤、植物叶片中微量元素和重金属元素含量。土壤中交换性Ca和Mg,有效Cu、Zn、Fe、Mn、B平均分别为49.34、8.75、0.24、1.04、17.10、3.51、0.11 mg/kg,分别为五级(很低)、五级、二级(高)、四级(低)、五级、三级(中)、二级;广宁红花油茶叶片Ca、Mg、Fe、Mn、B、Cu、Zn含量平均分别为8518.1、1063.2、53.76、1225.3、24.43、4.06、7.02 mg/kg,分别为正常、正常、正常、过量、正常、处于亏缺临界、缺乏,广宁红花油茶林分肥力不足。土壤重金属Pb、Cd、Cr、Ni、As平均含量分别为19.35、0.044、55.05、7.61、9.76 mg/kg,处于风险筛选值以下;广宁红花油茶叶片Cu、Zn、Pb、Cd、Cr、Ni、As值平均分别为4.06、7.02、0.68、0.044、0.39、4.77、0.030 mg/kg,远低于GAP药用植物标准限值,广宁红花油茶林地未受重金属污染。土壤交换性Ca和Mg,有效Fe、Mn、B、Cu、Zn含量,与广宁红花油叶片相应元素含量相关性不大,表明植物对各元素需求量差异大,植物吸收利用受土壤中元素间相互影响,因此,平衡施肥才能保证植物对营养元素的吸收利用。

The medium trace element and heavy metal for soil and leaf of Camellia semiserrata forest in Zhangmutou forest farm of Dongguan were investigated and analyzed.The average content of the exchangeable Ca and Mg,and the available Cu,Zn,Fe,Mn and B in soil were 49.34,8.75,0.24,1.04,17.10,3.51 and 0.11 mg/kg respectively,which were classified as grade 5 (very low),grade 5,grade 2 (high),grade 4 (low),grade 4,grade 5,grade 3 (medium) and grade 2 respectively.The average content of Ca,Mg,Fe,Mn,B,Cu and Zn in the leaves of C.semiserrata were 8518.1,1063.2,53.76,1225.3,24.43,4.06 and 7.02 mg/kg respectively,which were normal,normal,normal,excessive,normal,in the deficit critical and deficient.The fertility of C.semiserrata forest was insufficient.The average contents of Pb,Cd,Cr,Ni and As in soil were 19.35,0.044,55.05,7.61 and 9.76 mg/kg respectively,which were below the risk screening value.The average values of Cu,Zn,Pb,Cd,Cr,Ni and As in the leaves of C.semiserrata were 4.06,7.02,0.68,0.044,0.39,4.77 and 0.030 mg/kg respectively,all of which were far below the standard limits of GAP medicinal plants.The woodland of C.semiserrata was not polluted by heavy metals.The correlation of soil exchangeable Ca and Mg,available Fe,Mn,B,Cu,Zn content,and corresponding leaf element content of C.semiserrata were not significant.It showed that plants had different requirements for elements,and the elements in the soil were influenced each other,therefore,balanced fertilization can ensure the absorption and utilization of the required nutrients by plants.