Determining soil enzyme activities for the assessment of fungi and citric acid-assisted phytoextraction under cadmium and lead contamination.
Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under varied Cd and Pb pollution levels in a greenhouse pot experiment. We then determined accumulation of Cd and Pb in S. nigrum and the soil enzyme activities of dehydrogenase, phosphatase, urease, catalase, sucrase, and amylase. Detrended canonical correspondence analysis (DCCA) was applied to assess the interactions between remediation strategies and soil enzyme activities. Results indicated that the addition of fungi, CA, or their combination enhanced the root biomass of S. nigrum, especially at the high-pollution level. The combined treatment of CA and fungi enhanced accumulation of Cd about 22-47 % and of Pb about 13-105 % in S. nigrum compared with the phytoextraction alone. However, S. nigrum was not shown to be a hyperaccumulator for Pb. Most enzyme activities were enhanced after remediation. The DCCA ordination graph showed increasing enzyme activity improvement by remediation in the order of phosphatase, amylase, catalase, dehydrogenase, and urease. Responses of soil enzyme activities were similar for both the addition of fungi and that of CA. In summary, results suggest that fungi and CA-assisted phytoextraction is a promising approach to restoring heavy metal polluted soil.
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China.|Bor. S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, 200240, China.
Liang
L
Mao
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China.
Dong
D
Tang
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China.|Bor. S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, 200240, China.
Haiwei
H
Feng
Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
Yang
Y
Gao
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China. peizhousjtu@163.com.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China. peizhousjtu@163.com.
Pei
P
Zhou
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China.
Lurong
L
Xu
School of Agriculture and Biology, Shanghai Jiao tong University, Shanghai, 200240, China.|Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai, 200240, China.
Lumei
L
Wang
D001673:Biodegradation, Environmental / Q000187:drug effects; D018533:Biomass; D002104:Cadmium / Q000302:isolation & purification* / Q000378:metabolism; D019343:Citric Acid / Q000494:pharmacology*; D004798:Enzymes / Q000378:metabolism*; D005658:Fungi / Q000502:physiology*; D007854:Lead / Q000302:isolation & purification* / Q000378:metabolism; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000302:isolation & purification / Q000378:metabolism; D032324:Solanum nigrum / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology
D004798:Enzymes; D012989:Soil Pollutants; D002104:Cadmium; D019343:Citric Acid; D007854:Lead
Cadmium; Citric acid; Fungi; Lead; Soil enzymes; Solanum nigrum L