双金属氧化物和改性赤泥对潮褐土中外源砷的调控研究  

Regulation of Exogenous Arsenic in Meadow Cinnamon Soils by Applying Layered Double Oxides and Modified Red Mud

作　　者：孙媛媛[1] 曾希柏[1] 白玲玉[1] 王进进[1] 李莲芳[1] 苏世鸣[1] 王亚男[1] 段然[1] 吴翠霞[1] 

机构地区：[1]中国农业科学院农业环境与可持续发展研究所/农业部农业环境重点实验室,北京100081

出　　处：《农业环境科学学报》2013年第8期1545-1551,共7页Journal of Agro-Environment Science

基　　金：国家自然科学基金(41171255);国家"十二五"科技支撑计划(2012BAD14B02)

摘　　要：选取双金属氧化物(LDO)和两种改性赤泥(RM1和RM2)为钝化剂,应用室内模拟培养和盆栽试验的方法,研究了潮褐土中外源砷(As)添加量为10mg·kg-1和50mg·kg-1时,培养时间和钝化剂添加量对土壤砷有效性、小油菜吸收砷的调控效果。结果表明,添加钝化剂后,随着培养时间延长,土壤有效砷的含量均呈下降趋势,其中以LDO的调控效果最佳,培养12周时土壤有效砷含量分别降至1.06mg·kg-1(添加10mg·kg-1时)和5.77mg·kg-1(添加50mg·kg-1时);随着钝化剂添加量的增加,土壤中易溶态砷(AE-As)的含量逐渐降低,钙结合态砷(Ca-As)的含量则逐渐增加。3种钝化剂比较,添加LDO时铁结合态砷(Fe-As)含量降低,而添加RM2时铝结合态砷(Al-As)含量降低、Fe-As含量增加。盆栽实验结果表明,RM2能显著降低小油菜地上部分的砷含量,且对小油菜生长没有明显影响,在外源砷添加量为50mg·kg-1时,添加RM2后小油菜地上部分砷含量比CK降低了33.7%;LDO也可显著降低小油菜地上部分的砷含量,但同时抑制了小油菜生长,导致其产量显著低于CK。相对改性赤泥而言,采用LDO并不是调控潮褐土中砷有效性的较好选择。Using layered double oxides（LDO）and two types of modified red mud（RM1 and RM2）as amendments, simulating incubation and pot experiments with two levels of exogenous As（in 10 and 50 mg·kg^-1respectively）were conducted to study the influences of different incubation times and added amounts of amendments on arsenic（As）availability in soils and As uptake amounts by rape plants. The results indicated that available As decreased with incubation time prolonging. After incubated for 12 weeks, the available As contents of LDO treatment decreased to 1.06 and 5.77 mg·kg^-1when the exogenous As levels were in 10 and 50 mg·kg^-1respectively. With increasing of added amounts of all amendments, easily soluble arsenic（AE-As）contents decreased while calcium-bound arsenic（Ca-As）contents increased. Comparatively, iron-bound arsenic（Fe-As）contents in soils showed a negative correlation with the added amounts of LDO, but a positive correlation with the applied amounts of RM2. The aluminum-bound arsenic（Al-As）contents decreased with the added amounts of RM2 increased. Furthermore, the decreases of As uptake amounts in rape plants were varied to different types of amendments. Among all amendments, applying RM2 could significantly promote the growth of rape and reduce the As uptake amounts in rape plants by 33.7% compared to control as the exogenous As level was in 50 mg·kg^-1. Oppositely, applying LDO could inhibit the growth of rape and reduce the As uptake amounts in rape as well. However, LDO is improper choice relative to modified red mud in regulating the availability of arsenic in meadow cinnamon soils.

关 键 词：双金属氧化物 改性赤泥 潮褐土 外源砷 砷形态 小油菜 

分 类 号：S153[农业科学—土壤学]