不同种植密度高粱对耕地重金属污染的修复效果

Remediation effect on heavy metal pollution of sorghum planting density

以高粱品种N5D61号为材料,研究了5种种植密度(16.50、14.63、12.75、10.88、9.00万株/hm^2)高粱对耕地5种重金属(镉、铅、铬、砷、锰)的修复效果。结果表明:低密度种植(12.75、10.88、9.00万株/hm^2)时,单株生物产量较高,但16.5万株/hm^2的高密度种植可获得高于另外处理的实际生物产量;在对重金属的吸收修复作用上,植株各部位对不同重金属的吸收效果有差异;通过对富集系数进行分析发现,N5D61对镉和铬的富集系数较高,根部的富集系数达6.00以上;对锰、砷和铅的富集系数小于1,其中对铅的富集系数只有0.1左右;种植密度16.5、14.63、10.88万株/hm^2下对重金属的吸收总量较大。综合考虑,16.5万株/hm^2为获得高生物产量和高重金属吸收量的最佳种植密度。

The remediation effects on cadmium, lead, chromium, arsenic and manganese pollution in cultivated land under five different planting densities（165 000, 146 300, 127 500, 108 800, 90 000 plants/hm^2） were studied. The results showed that planting density in the 127 500,108 800 and 90 000 plants/hm^2, comprehensive growth index were better than that of other plant density treatments; The planting densities of 16 5000 plants/hm^2 were higher than those of other treatments; The enrichment coefficients of Cd and Cr in root were more than 6.00, the enrichment coefficients of manganese, arsenic and lead were less than 1, the enrichment coefficient of Pb is only about 0.1. At 165 000, 146 300 and 108 800 plants/hm^2, the total uptake of heavy metals was larger. Comprehensive consideration, the best density was 165 000 plants/hm^2 to obtain high biological yield and high heavy metal uptake.