title: Cd immobilization in a contaminated rice paddy by inorganic stabilizers of calcium hydroxide and silicon slag and by organic stabilizer of biochar.
abstract: A field experiment was conducted in a Cd-contaminated rice paddy field to evaluate the effect of inorganic and organic metal stabilizers on Cd mobility and rice uptake. A dose of inorganic stabilizer of calcium hydroxide (CH), silicon slag (SS), and wheat straw biochar (BC) was amended respectively to topsoil before rice transplanting. Rice production was managed with the same water regime and fertilization practices consistently between treatments including a control without amendment. Samples of topsoil and rice plant were collected at rice harvest to analyze the Cd mobility and uptake by rice. Without affecting rice grain yield, the stabilizers significantly decreased CaCl2-extractable Cd in a range of 44 to 75 % compared to the control, corresponding to soil pH changes under the different treatments. Accordingly, Cd concentrations both in rice tissue and in rice grain were very significantly decreased under these treatments. The decrease in rice Cd uptake was correlated to the decrease in extractable Cd, which was again correlated to soil pH change under the different treatments, indicating a prevalent role of liming effect by the amendments. While applied at a large amount in a single year, organic stabilizer of BC decreased Cd extractability by up to 43 % and Cd rice uptake by up to 61 %, being the most effective on Cd immobilization. However, the long-term effect on soil health and potential tradeoff effects with different stabilizers deserve further field monitoring studies.
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.|Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Rongjun
authors: R
authors: Bian
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.|Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Lianqing
authors: L
authors: Li
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Dandan
authors: D
authors: Bao
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Jinwei
authors: J
authors: Zheng
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Xuhui
authors: X
authors: Zhang
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Jufeng
authors: J
authors: Zheng
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Xiaoyu
authors: X
authors: Liu
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
authors: Kun
authors: K
authors: Cheng
authors: Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China. gxpan1@hotmail.com.|Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China. gxpan1@hotmail.com.
authors: Genxing
authors: G
authors: Pan
mesh_terms: D002104:Cadmium / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D002126:Calcium Hydroxide / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D003362:Cost-Benefit Analysis; D052918:Environmental Restoration and Remediation / Q000191:economics; D006863:Hydrogen-Ion Concentration; D012275:Oryza / Q000254:growth & development / Q000378:metabolism; D012825:Silicon / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism
chemical_list: D012989:Soil Pollutants; C540010:biochar; D002104:Cadmium; D002606:Charcoal; D002126:Calcium Hydroxide; D012825:Silicon
keywords: Biochar; Cadmium; Metal stabilizer; Rice paddy; Soil mobility