Fertilization Enhances Grain Inorganic Arsenic Assimilation in Rice
Fertilization Enhances Grain Inorganic Arsenic Assimilation in Rice
复制标题
施肥促进水稻籽粒对无机砷的吸收
DOI：
10.1007/s12403-023-00563-y
复制
发表时间：
2023-05-26
影响因子：
6.7
通讯作者：
Meharg, Caroline
中科院分区：
文献类型：
--
作者：
Begum, Monira;Li, Litian;Meharg, Caroline
为了研究土壤施肥/改良剂如何改变水稻中砷形态的谷物吸收量，水稻在生长室中生长成熟，生长室中施用标准矿物肥料、木灰（富含二氧化硅）、猪泥浆（富含有机质）和非改良对照。土壤来源于中国稻田。各处理的主要施肥元素（氮、磷、钾）保持不变。孔隙水化学和土壤微生物学监测整个实验。籽粒总砷（无机砷和二甲基胂酸（DMA）之和）在处理间差异显著（P = 0.024），对照无机砷含量为0.025 ~ 0.08 mg/kg，DMA含量为0.08 ~ 0.16 mg/kg。肥料来源对砷在籽粒中的形态含量没有影响。孔隙水分析发现，随着厌氧作用的开始，无机砷、磷和锰的浓度大大降低。甲基化砷物种的浓度随时间增加，同时在pH值的增加，减少Eh，并增加总有机碳和铁，没有强大的治疗效果，除了猪泥浆，提高pH值和降低Eh。产甲烷古菌、硫酸盐还原菌和酸性细菌随时间增加，部分放线菌和厚壁菌因泥浆而增加，但随后随时间减少（P < 0.01）。产甲烷古菌和硫酸盐还原菌与间隙水DMA呈正相关，与间隙水无机砷呈负相关（P < 0.05）。放线菌属和伯克霍尔德菌科与DMA呈负相关，而铁还原菌属（梭菌目）与间隙水无机砷和DMA呈正相关（P < 0.05）。
To investigate how soil fertilization/amendments alters arsenic speciation grain off-take in paddy rice, rice was grown to maturity in growth chambers fertilized with standard mineral fertilizer, wood ash (rich in silica), pig slurry (rich in organic matter), and non-amended control. The soil was sourced from a Chinese paddy field. The primary fertilized elements (nitrogen, phosphorus, potassium) were kept constant across treatments. Porewater chemistry and soil microbiology were monitored throughout the experiments. Total grain arsenic, sum of inorganic arsenic and dimethylarsinic acid (DMA), was significantly different between treatments (P = 0.024), with inorganic arsenic varying from 0.025 to 0.08 mg/kg and DMA from 0.08 to 0.16 mg/kg for control compared to fertilized, respectively. Fertilizer source made no difference to arsenic speciation concentration in grain. Porewater analysis found that as anaerobism set in, inorganic arsenic, phosphorus and manganese greatly lowered in concentration. Methylated arsenic species concentrations increased over time, concurrent with an increase in pH, decrease in Eh, and increase in total organic carbon and iron, with no strong treatment effects, except for pig slurry that enhanced pH and decreased Eh. Methanogenic archaea, sulfate-reducing bacteria and Acidobacteria increased with time and some Actinobacteria and Firmicutes increased due to slurry, but then decreased with time (P < 0.01). Methanogenic archaea and sulphate-reducing bacteria correlated positively with porewater DMA and negatively with porewater inorganic arsenic (P < 0.05). Genera within the Actinobacteria and Burkholderiaceae correlated negatively with DMA, while genera with iron-reducing capacity (Clostridiales) correlated positively with porewater inorganic arsenic and DMA (P < 0.05).