富硅生物炭对红壤性稻田土壤镉形态及水稻镉吸收与转移的影响  

Effects of Silicon-enriched Biochar on Soil Cadmium Speciation and Cadmium Uptake and Transfer in Reddish Paddy Soil

作　　者：胡祖武 吴多基 夏李佳 姚冬辉 魏宗强[1] 吴建富[1] HU Zuwu;WU Duoji;XIA Lijia;YAO Donghui;WEI Zongqiang;WU Jianfu(College of Land Resources and Environment,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]江西农业大学国土资源与环境学院,江西南昌330045

出　　处：《江西农业大学学报》2022年第4期1034-1043,共10页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金项目(31660596);国家重点研发计划项目(2017YFD0301601)。

摘　　要：【目的】农田土壤Cd污染已成为突出的环境问题,Cd污染修复技术备受关注。研究富硅生物炭对红壤性稻田土壤镉形态含量及水稻镉吸收、累积与转移的影响,旨在为富硅生物炭对镉污染农田修复提供科学依据。【方法】以南方镉污染的红壤性水稻土为研究对象,采用盆栽试验,在等量氮磷钾养分投入条件下,以不添加生物炭的处理为对照(CK),研究不同添加量(0.2%和0.4%)的低硅(BW3)和高硅(AH、AB)含量的3种不同类型生物炭对土壤镉形态含量及水稻产量、生物量和镉吸收、累积的影响。【结果】添加富硅生物炭,土壤中可交换态和还原态镉占比均降低,而可氧化态和残渣态镉占比均增加。水稻各部位镉含量由大到小依次为根、秸秆和籽粒。与CK相比,生物炭的添加显著降低了水稻各部位镉含量,其中以添加0.4%高硅生物炭AB的处理降低效果最为明显,比CK降低了66.85%(P<0.05);秸秆镉的含量变化规律与籽粒变化趋势基本一致;根系镉的含量在两种施加量水平下,由大到小均表现为CK、BW3、AH和AB,且差异显著(P<0.05)。添加富硅生物炭提高了水稻产量、秸秆和根系生物量。在两种施加量水平下,籽粒产量、秸秆生物量、根系生物量均表现为低硅生物炭(BW3)和高硅生物炭(AH、AB)间差异显著(P<0.05)。相较于CK,添加富硅生物炭显著降低了水稻镉富集系数(BCF),降幅为14.52%~36.32%。转移系数TF1(根部到秸秆)和TF2(根部到籽粒)变化规律大致相似。无论是高量还是低量添加富硅生物炭,TF1和TF2均显著小于CK处理(P<0.05),降幅分别为50.64%~57.39%、48.87%~56.05%和31.39%~47.67%、29.06%~45.34%。【结论】添加富硅生物炭能改变镉污染农田土壤镉形态含量,降低镉的生物有效性,从而减少水稻对镉的吸收;同时,还能够提高水稻生物量和籽粒产量。综上所述,富硅生物炭可以作为镉污染农田修复的一种调理剂,尤其是�[Objective]Cadmium(Cd)contamination of agricultural soil has become a prominent environmental problem,and Cd pollution remediation technology has attracted much attention.This study investigates the effects of silicon-rich biochar on Cd speciation in red paddy soil and Cd uptake,accumulation and transfer in rice,in order to provide a scientific basis for the remediation of Cd-contaminated paddy soil using silicon-enriched biochar.[Method]A pot experiment was established with 7 treatments,which included CK(without fertilizer or biochar input)and three types of biochar added at two levels each(i.e.,0.4% and 0.8%).The three types biochar were classified into two groups based on their Si contents:biochar with lower Si content(BW3),and biochar with higher Si content(AH and AB).The soil used in the pot experiment was reddish paddy soil.[Result]The addition of silicon-enriched biochar changed the distribution of Cd forms in the soil.The proportion of exchangeable-Cd and reduced-Cd in the soil decreased,while the proportion of oxidizable-Cd and residual-Cd increased.The order of Cd content in rice tissues was root>straw>grain.The addition of biochar significantly reduced the Cd contents of rice tissues.The order of Cd in rice grain for each treatment was CK>BW3>AH>AB,and the effect of AB biochar with 0.4% addition rate was the most significant,which was 66.85% lower than that of CK.The variation of Cd content in straw was generally the same as that in grain.The order of root Cd content was CK>BW3>AH>AB at each biochar application level(P<0.05).The addition of silicon-enriched biochar increased rice yield,straw and root biomass.At each application level,there were significant differences between lower silicon biochar(BW3)and higher silicon biochar(AH,AB)for grain yield,straw biomass,and root biomass.Compared with CK,the addition of silicon-enriched biochar significantly reduced the Cd enrichment coefficient in rice by 14.52%-36.32%;the changes of transfer coefficients TF1(root to straw)and TF2(root to grain)were roughly s

关 键 词：富硅生物炭 红壤性水稻土 土壤镉形态 水稻产量 镉吸收与转移 

分 类 号：X53[环境科学与工程—环境工程]