陕西省安康市西部稻田土壤硒形态特征与水稻富硒状况研究  

A study of the Selenium speciation in paddy soil and status of selenium-enriched rice in western part of Ankang City,Shaanxi Province

作　　者：王仁琪 张志敏 晁旭 冯海艳[1] 杨忠芳[1] WANG Renqi;ZHANG Zhimin;CHAO Xu;FENG Haiyan;YANG Zhongfang(School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China;National Research Center for Geoanalysis,Chinese Academy of Geological Sciences,Beijing,100037 China;Shaanxi Institute of Geological Survey,Xi'an 710054,Shaanxi,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质科学院国家地质实验测试中心,北京100037 [3]陕西省地质调查院,陕西西安710054

出　　处：《中国地质》2022年第2期398-408,共11页Geology in China

基　　金：陕西省地质调查院公益性地质调查项目(201909)资助。

摘　　要：【研究目的】对土壤中硒元素的有效吸收是水稻富硒的关键,而土壤中硒的形态则是影响水稻吸收能力的直接影响因素之一,为了探讨影响富硒土壤中硒的形态与水稻籽实中硒含量的关系,本文对陕西省安康市西部土壤开展了定量研究。【研究方法】本文对研究区土壤硒的形态以及水稻富硒状况进行测定,获得了土壤中各形态硒的赋存状态分布特征。【研究结果】安康市西部富硒土壤中各形态硒的含量差异较大,其中腐殖酸态、强有机态和残渣态的硒含量较高,占总硒的90%以上;而水溶态、离子交换态、铁锰态、碳酸盐态的硒含量较低,占总硒比例低于5%;当地土壤中水溶态、离子交换态硒与水稻对硒的吸收有着密切相关性,这与其他学者近期的研究结果类似,为富硒水稻的开发提供理论基础;研究区水稻籽实中硒的平均含量为0.20 mg/kg,达到国家富硒水稻的标准。【结论】研究区土壤富硒状况良好,水稻籽实中硒的含量符合国家富硒标准,富硒水稻的开发具有广阔前景。This paper is the result of agricultural geological survey engineering.[Objective]The uptake and accumulation of selenium in rice grain is determined by the bioavailability of selenium in paddy soils,which can be directly affected by its speciation pattern.In this study, the selenium speciation in soils from the west of Ankang City,Shaanxi province was analyzed to investigate the correlation of selenium content in rice grain with the speciation pattern of selenium in soils. [Methods] The distribution characteristics of seleniumspeciation in soils was examined by analyzing the concentrations of selenium in soils and rice grain.[Results] The concentrations of speciation fractions varied significantly. Detailedly, the humic acid boundfraction of selenium accounted for more than 90% of the total content, whereas the water-solublefraction, ion-exchangeable fraction, manganese oxides fraction and carbonate bounded fraction occupied less than 5%. This study observed a tight relationship between the rice uptake of selenium and its concentration ofwater-soluble fraction andion-exchangeable fraction in paddy soils,which was consistent with the results found in previous studiesand will provide fundamental basis for the development of seleniumrich rice. The average concentration of selenium in rice grainwas 0.20 mg/kg, which met the national standard. [Conclusions] The enrichment degree of selenium in paddy soils from the study area was high. This caused the relative accumulation of selenium in rice grain, which met the national standard. This study reveals broad prospects in the development of selenium-rich rice.

关 键 词：硒元素 稻田 富硒水稻 土壤地球化学 农业地质调查工程 硒形态 安康 陕西省 

分 类 号：S153.6[农业科学—土壤学] S511[农业科学—农业基础科学]