摘要
【目的】探究添加蚯蚓对尾叶桉在经污泥改良的稀土矿废弃地土壤上的生长、重金属累积及种植后基质重金属变化的影响,为污泥资源化利用和矿区废弃地生态修复提供依据。【方法】以经污泥改良的稀土矿废弃地土壤为研究对象,通过盆栽试验探究不同赤子爱胜蚓添加量(40、60、80条·kg^(-1))对尾叶桉生长、重金属累积的影响,基于熵权TOPSIS模型进行综合评价,分析种植后基质重金属形态变化特征。【结果】与未经改良的废弃地土壤(对照)相比,污泥施用显著增加尾叶桉地上部生物量和地上、地下部Cu、Zn含量以及地下部Cd含量。与单施污泥相比,不同蚯蚓添加量均显著增加尾叶桉株高、总生物量、地上部Cd含量和不同部位Cu、Zn含量,植株Cu、Zn、Cd累积量分别显著增加1.61~2.27倍、2.37~2.93倍和0.93~1.35倍,添加量为60条·kg^(-1)时尾叶桉Zn累积量最高。不同处理下植物生长适应性及重金属累积综合评价得分排序为:污泥+60条·kg^(-1)蚯蚓(0.842)>污泥+40条·kg^(-1)蚯蚓(0.829)>污泥+80条·kg^(-1)蚯蚓(0.823)>单施污泥(0.174)>对照(0.134)。与对照相比,单施污泥显著增加种植后基质Cu、Zn、Cd全量及其不同形态含量;与单施污泥相比,不同蚯蚓添加量均显著减少种植后基质Cu、Zn、Cd全量以及不同形态Cd含量和交换态、碳酸盐结合态Cu、Zn含量。【结论】在用污泥改良稀土矿废弃地土壤时,添加赤子爱胜蚓可有效促进尾叶桉生长及其对Cu、Zn、Cd的吸收累积作用,从而在一定程度上降低土壤重金属全量及易被植物吸收的有效态含量。
【Objective】This study investigated the effects of earthworms on the growth and the absorption of heavy metals of Eucalyptus urophylla in the abandoned rare-earth mine land soil amended by sewage sludge,as well as the change of heavy metals in the substrate after planting,in order to provide a basis for the resource utilization of sewage sludge and the ecological remediation in the abandoned rare-earth mine land.【Method】Taking the abandoned rare-earth mine land soil amended by sewage sludge as the research object,a potting experiment was conducted to investigate the effects of earthworms(0,40,60 and 80 individual adult Eisenia fetida kg^(-1))on the growth and heavy metal accumulation of Eucalyptus urophylla.Based on the entropy weight TOPSIS model,a comprehensive evaluation was conducted.The characteristics of heavy metal speciation in substrates after planting were analyzed.【Result】The results showed that compared with the abandoned rare-earth mine land soil(CK),the application of sewage sludge significantly increased the aboveground biomass and Cu,Zn contents in both shoots and roots,as well as the Cd contents in roots of Eucalyptus urophylla.Compared with the single application of sewage sludge,additionally applying earthworms(40,60,and 80 individual adult Eisenia fetida kg^(-1))significantly increased plant height,total plant biomass,the Cd content in shoots,and the Cu and Zn contents in both shoots and roots of Eucalyptus urophylla.The Cu,Zn and Cd contents of Eucalyptus urophylla increased by 1.61-2.27 times,2.37-2.93 times and 0.93-1.35 times,respectively.The Zn accumulation of Eucalyptus urophylla after application of 60 individual adult Eisenia fetida kg^(-1) was significantly higher than those of other treatments.The comprehensive evaluation scores of plant growth adaptability and accumulation of heavy metals under different treatments were ranked as follows:sewage sludge+60 individual adult Eisenia fetida kg^(-1) earthworms(0.842)>sewage sludge+40 individual adult Eisenia fetida kg^(-1) eart
作者
苏思宁
阮可瑾
冯嘉仪
冯为迅
梁智淇
吴道铭
曾曙才
SU Sining;RUAN Kejin;FENG Jiayi;FENG Weixun;LIANG Zhiqi;WU Daoming;ZENG Shucai(College of Forestry and Landscape Architecture,South China Agricultural University,Guangzhou 510642,Guangdong,China;GuangDong MaoMing Agriculture&Forestry Techical College,Maoming 525000,Guangdong,China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2022年第7期137-146,共10页
Journal of Central South University of Forestry & Technology
基金
国家自然科学基金项目(31971629,41807112)
广东省林业科技创新项目(2017KJCX061)。
关键词
生态修复
城市污泥
重金属
植物修复
赤子爱胜蚓
ecological restoration
sewage sludge
heavy metals
phytoremediation
Eisenia fetida
