title: Effectiveness of lime and peat applications on cadmium availability in a paddy soil under various moisture regimes.
abstract: In paddy soils, amendments and moisture play important role in the immobilization of cadmium (Cd). The effects of applying lime, peat, and a combination of both on soil Eh, pH, and Cd availability in contaminated soils were investigated under wetted (80 ± 5 % of water holding capacity) and flooded (completely submerged) conditions. In wetted soils, there was little change in Eh, compared to flooded soils where Eh reduced rapidly. Amendments of lime only or in a mixture with peat increased soil pH to different degrees, depending on the lime application rate. However, peat addition only slightly affected soil pH. The decreased Cd availability in flooded soils was related to submergence duration and was significantly lower than that in wetted soils after 14 days. Liming wetted and flooded soils decreased exchangeable Cd and increased carbonates or Fe-Mn oxides bound fractions, while peat addition transformed Cd from carbonates to organic matter bound fractions. The combined application of peat and lime generally showed better inhibitory effects on the availability of Cd than separately application of lime or peat. Higher application rates of lime, peat, or their mixture were more effective at reducing Cd contamination in flooded soil. This indicates that application of peat and lime mixture under flooded conditions was most effective for in situ remediation of Cd-contaminated soils. Further studies are required to assess the long-term effectiveness of the peat and lime mixture on Cd availability in paddy soils.
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Chen
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Tuanhui
authors.initials: T
authors.lastname: Xie
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Qiaofeng
authors.initials: Q
authors.lastname: Liang
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Mengjiao
authors.initials: M
authors.lastname: Liu
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Mingliu
authors.initials: M
authors.lastname: Zhao
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
authors.forename: Mingkuang
authors.initials: M
authors.lastname: Wang
authors.affiliation: College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China. 1400619353@qq.com.
authors.forename: Guo
authors.initials: G
authors.lastname: Wang
mesh_terms: D002104:Cadmium / Q000032:analysis / Q000737:chemistry*; D017610:Calcium Compounds; D055868:Floods; D012275:Oryza; D010087:Oxides / Q000032:analysis; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; C016538:lime
keywords: Cadmium availability; Lime; Peat; Sequential extraction; Soil water management