氯基和硫基肥对土壤镉水稻生物有效性的影响  

Effects of Chlorine-based and Sulfur-based Fertilizers on Rice Bioavailability of Cd in Soils

作　　者：欧阳晴雯 龙坚 郝汉驰 王文禹 李耀 黄奕航 侯红波 彭佩钦 OUYANG Qing-wen;LONG Jian;HAO Han-chi;WANG Wen-yu;LI Yao;HUANG Yi-hang;HOU Hong-bo;PENG Pei-qin(College of Environmental Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Hunan Engineering Laboratory for Control of Rice Quality and Safety,Changsha 410004,China)

机构地区：[1]中南林业科技大学环境科学与工程学院,长沙410004 [2]稻米品质安全控制湖南省工程实验室,长沙410004

出　　处：《环境科学》2023年第10期5737-5745,共9页Environmental Science

基　　金：国家自然科学基金项目(42107444);湖南省教育厅科学研究项目(21B0245);湖南省2020高新技术产业科技创新引领计划项目(2020NK2021)。

摘　　要：为探明氯基和硫基化肥单施或混施对土壤镉(Cd)水稻生物有效性的影响,选取典型水稻土红黄泥(第四纪红色黏土母质发育),按不同比例添加氯基肥(KCl、NH_(4)Cl)和硫基肥[K_(2)SO_(4)、(NH_(4))_(2)SO_(4)],在3种外源Cd水平下(0、0.5和2.0 mg·kg^(-1))进行水稻盆栽试验,研究土壤pH、Cd形态、水稻植株各部位和糙米Cd富集情况.结果表明,施用氯基和硫基肥均会使土壤酸化,但氯基肥的影响更显著.水稻灌浆期,单施氯基肥较单施硫基肥的土壤pH值平均降低了0.28;水稻成熟期,氯基肥对残渣态Cd具有活化作用,而硫基肥会将酸可提取态Cd钝化为残渣态;氯基和硫基肥混施较单施同种肥料更易促进水稻植株富集Cd;糙米Cd富集量在氯基和硫基肥1:1处理时最高,为0.21 mg·kg^(-1)(2.0 mg·kg^(-1)外源Cd水平),较单施氯基肥提高了16.4%,较单施硫基肥显著提高了113.3%.因此,氯基肥和硫基肥混施会使水稻糙米Cd富集量上升,为保障粮食品质安全,水稻种植更宜单施硫基肥.To explore the effects of single or combined application of chlorine-and sulfur-based fertilizers on rice bioavailability of Cd in soils,pot experiments with reddish clayey soil(developed from quaternary red clay parent materials)under three exogenous Cd levels(0,0.5,and 2.0 mg·kg^(-1))were conducted.Meanwhile,chlorine-based fertilizers(KCl,NH_(4)Cl)and sulfur-based fertilizers[K_(2)SO_(4),(NH_(4))_(2)SO_(4)]were added in different proportions.The soil pH,Cd morphology,and Cd accumulation in rice at different growth stages were analyzed.The results revealed that both chlorine-and sulfur-based fertilizers could acidify the soil;however,the effect of chlorine-based fertilizers was more significant.During the filling stage of rice,the soil pH value of the treatment of applying single chlorine-based fertilizer decreased by 0.28 on average compared with that of applying single sulfur-based fertilizer.At the maturity stage of rice,chlorine-based fertilizer could activate the residual Cd,whereas sulfur-based fertilizer passivated the acid-extracted Cd to its residual state.Compared with the single application of the same fertilizer,the combined application of chlorine-and sulfur-based fertilizers was more likely to promote the accumulation of Cd in rice plants.The highest Cd accumulation of brown rice was 0.21 mg·kg^(-1)(2.0 mg·kg^(-1)exogenous Cd level)in the 1:1(mole ratios of Cl:S)treatment of chlorine-and sulfur-based fertilizers,which was 16.4%higher than that of single chlorine-based fertilizer and 113.3%higher than that of single sulfur-based fertilizer.Therefore,the combined application of chlorine-fertilizers and sulfur-based fertilizers will increase the concentration of Cd in brown rice.To ensure food quality and safety,it is more advisable to apply single sulfur-based fertilizer for rice planting.

关 键 词：氯基肥 硫基肥 水稻 镉(CD) 生物有效性 

分 类 号：X171.5[环境科学与工程—环境科学]