In situ stabilization of heavy metals in multiple-metal contaminated paddy soil using different steel slag-based silicon fertilizer.
Steel slag has been widely used as amendment and silicon fertilizer to alleviate the mobility and bioavailability of heavy metals in soil. The objective of this study was to evaluate the influence of particle size, composition, and application rate of slag on metal immobilization in acidic soil, metals uptake by rice and rice growth. The results indicated that application of slag increased soil pH, plant-available silicon concentrations in soil, and decreased the bioavailability of metals compared with control treatment, whereas pulverous slag (S1) was more effective than granular slag (S2 and S3). The acid-extractable fraction of Cd in the spiked soil was significantly decreased with application of S1 at rates of 1 and 3 %, acid-extractable fractions of Cu and Zn were decreased when treated at 3 %. Use of S1 at both rates resulted in significantly lower Cd, Cu, and Zn concentrations in rice tissues than in controls by 82.6-92.9, 88.4-95.6, and 67.4-81.4 %, respectively. However, use of pulverous slag at 1 % significantly promotes rice growth, restricted rice growth when treated at 3 %. Thus, the results explained that reduced particle size and suitable application rate of slag could be beneficial to rice growth and metals stabilization.
Ministry of Agriculture Key Laboratory of Crop Water Use and Regulation, Institute of Farmland Irrigation Research, Chinese Academy of Agricultural Sciences, Xinxiang, 453002, China. smile_0808@163.com.
Dongfeng
D
Ning
Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
Yongchao
Y
Liang
Ministry of Agriculture Key Laboratory of Plant Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Alin
A
Song
Ministry of Agriculture Key Laboratory of Crop Water Use and Regulation, Institute of Farmland Irrigation Research, Chinese Academy of Agricultural Sciences, Xinxiang, 453002, China.
Aiwang
A
Duan
Ministry of Agriculture Key Laboratory of Crop Water Use and Regulation, Institute of Farmland Irrigation Research, Chinese Academy of Agricultural Sciences, Xinxiang, 453002, China.
Zhandong
Z
Liu
D000383:Agriculture / Q000295:instrumentation*; D001682:Biological Availability; D005308:Fertilizers; D019216:Metals, Heavy / Q000032:analysis* / Q000378:metabolism; D012275:Oryza / Q000254:growth & development / Q000378:metabolism; D012825:Silicon; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism; D013232:Steel
D005308:Fertilizers; D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D013232:Steel; D012825:Silicon
BCR; Heavy metals; Rice; Silicon; Steel slag