连续施硅对双季稻镉硅累积效应的影响  

Impacts of Uptake and Accumulation of Cd on Double Rice-Paddy Soil by Silicon Fertilizer Continuous Application

作　　者：彭华[1,2,3] 邓凯 石宇[4] 魏维 柳赛花 纪雄辉[1,2,3,5] PENG Hua;DENG Kai;SHI Yu;WEI Wei;LIU Sai-hua;JI Xiong-hui(Hunan Institute of Agricultural Environment and Ecology,Hunan Academy of Agricultural Sciences,Changsha 410125,China;Ministry of Agriculture and Rural Affairs Key Laboratory of Agriculture Environment in Middle Reach Plain of Yangtze River,Changsha 410125,China;Key Laboratory of Prevention,Control and Remediation of Soil Heavy Metal Pollution in Hunan Province,Changsha 410125,China;Xiangxi Station of Soil and Fertilizer,Jishou 416000,China;Long Ping Branch of Hunan University,Changsha 410000,China)

机构地区：[1]湖南省农业科学院,湖南省农业环境生态研究所,长沙410125 [2]农业农村部长江中游平原农业环境重点实验室,长沙410125 [3]稻田土壤重金属污染防控与修复湖南省重点实验室,长沙410125 [4]湖南湘西州农业农村局土壤肥料工作站,吉首416000 [5]湖南大学隆平分院,长沙410000

出　　处：《环境科学》2022年第8期4271-4281,共11页Environmental Science

基　　金：湖南省重点研发计划项目(2019WK2031);湖南省农业科学院创新项目(2020CX56)。

摘　　要：为研究硅肥对土壤镉生物有效性以及双季稻对镉硅积累的影响,在稻田土壤镉较高[ω(总Cd)为1.03 mg·kg^(-1)]污染条件下,开展双季稻连续基施硅肥180 kg·hm^(-2)(以SiO_(2)计)的田间定位试验.结果表明,双季稻田连续施用硅肥能够增加土壤有效硅含量,增幅为108.1%~275.0%,同时提高土壤1.15~1.33个pH单位,施用硅肥早、晚稻土壤DTPA-Cd含量降幅分别为12.3%和15.9%,差异达显著水平;施硅促进了土壤镉向稳定形态的转化,土壤可交换态EXC-Cd含量降幅为2.6%~5.1%,QW处理降低达显著水平;施硅肥处理,碳酸盐结合态CAR-Cd含量降低,降幅为8.6%~24.9%,显著增加了铁锰氧化态FMO-Cd含量,增加了土壤有机结合态OR-Cd含量,增幅为2.3%~12.8%,残渣态RES-Cd含量增幅为2.3%~6.0%;连续施硅肥降低了水稻对镉的积累,早稻根、茎叶和稻米平均降幅分别为38.4%、 49.7%和50.9%,晚稻根、茎叶和稻米平均降幅分别为30.6%、 34.4%和39.2%;硅处理显著降低了水稻根吸收系数(AF_(土/根)),降幅为25.5%~49.6%,同时降低了水稻根向茎叶的转运系数(T_(根/茎叶)),降幅为13.5%~52.6%,差异显著,早、晚稻稻米镉富集系数(BAF)分别平均降低6.0%和8.0%,其中粉末状硅肥对降低水稻镉吸收效果最佳.综上表明硅肥能够降低水稻对镉的吸收积累,然而硅肥持续性降镉效应不明显.The impacts of silicon(Si) fertilizers on cadmium(Cd) bioavailability in soil and Cd accumulation in paddy-rice plants were investigated in a field positioning test.The results indicated that the continuous application of 180 kg·hm^(-2) Si fertilizers improved soil bioavailable Si in paddy-rice fields by 108.1%-275.0% and improved pH values by 1.15-1.33 in soil.The difference in the contents of DTPA-Cd in soil by 12.3% and 15.9% was significant in early and late rice,respectively.The continuous application of silicon promoted the transformation of soil cadmium to a stable form and reduced the contents of exchangeable Cd and carbonate binding state Cd in the soil by 2.6%-5.1% and 8.6%-24.9%.The contents of ferric manganese oxide binding state Cd were increased significantly;meanwhile,the contents of organic binding state Cd and residue state Cd in soil were improved by 2.3%-12.8% and 2.3%-6.0%,respectively.The contents of Cd in the root,shoot,and rice were reduced by 38.4%,49.7%,and 50.9% in early season rice and by 30.6%,34.4%,and 39.2% in late season rice,respectively.The absorption factors and translocation factors were reduced significantly by 25.5%-49.6% and 13.5%-52.6%,and the average bioaccumulation factors were decreased by 6.0% and 8.0% in early and late season rice.The powder Si fertilizer had the best results overall.In conclusion,Si fertilizer could reduce the absorption and accumulation in rice;however,the continuous Cd reduction effect of continuous application Si fertilizer was not obvious.

关 键 词：双季稻 硅肥 镉(CD) 生物有效性 迁移转运 

分 类 号：X171.5[环境科学与工程—环境科学]