樱桃种植区土壤及樱桃重金属富集状况研究

Study on Heavy Metal Enrichment of Cherries and Soils in Cherry Growing Region

为研究西北干旱樱桃种植区樱桃重金属富集状况及其与土壤重金属含量之间的关系,采用内梅罗指数法和富集系数法对土壤及樱桃重金属富集状况进行评价。结果表明:以《土壤环境质量标准》作为评价标准,发现樱桃种植区土壤未受到严重的重金属污染;从土壤重金属空间分布格局来看,种植区东北部土壤重金属污染较西南部污染严重;樱桃各部位(叶片、果皮、果肉)中Cd、Cu、Pb、Zn、Cr等5种重金属元素的含量差异较大,叶片和果皮中Pb、Cr、Cd超标,果肉中Pb、Cd超标;樱桃不同部位的重金属富集量存在较大的差异,总体趋势为叶片>果皮>果肉;不同重金属元素被樱桃同一器官吸收富集的能力存在较大的差异,在叶片部位重金属元素富集能力大小依次为Cd>Cu>Pb>Zn>Cr,在果皮部位重金属元素富集能力大小依次为Cd>Cu>Zn>Pb>Cr,在果肉部位重金属元素富集能力大小依次为Cd>Cu>Pb=Zn>Cr;Cd在樱桃叶片、果皮、果肉的富集系数均为最大,具有较强的潜在生态风险。

To study the enrichment of heavy metals in cherry growing area and its relationship with soil heavy metal content in arid cherry growing area in Northwest China,the enrichment condition of heavy metals in soil and cherry was evaluated using Nemerow index and enrichment index. The results showed that with the ＂soil environment quality standard＂as the evaluation criteria it was found that the soil of cherry growing area was not seriously polluted by heavy metals. From the view of the spatial distribution pattern of heavy metals in the soil,the heavy metal pollution in the northeast soil was more serious than that in the southwest; the contents of Cd,Cu,Pb,Zn,Cr in various parts（ leaf,peel and pulp） of cherry were different,the contents of Pb,Cr and Cd in the leaf and peel were higher than the standard; the content of Pb and Cd exceeded the standard in the pulp. In addition,the accumulation of heavy metals in different parts of cherry had a big difference,and the overall trend was leaf 〉peel 〉pulp. While the abilities that different heavy metals were absorbed by the same organ were different,and the enrichment abilities of heavy metals were also different. The enrichment abilities of heavy metal elements in the leaf was in the order of Cd〉 Cu 〉Pb 〉Zn 〉Cr; the enrichment ability of the heavy metal elements in the peel area were Cd 〉Cu〉 Zn 〉Pb 〉Cr; the enrichment ability of the heavy metal elements in the pulp was in orderof Cd〉 Cu 〉Pb = Zn 〉Cr. In conclusion,the enrichment index of Cd in leaf,peel and pulp of cherries was the largest,which indicated a strong potential ecological risk.