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

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...

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

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 selenium-rich 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.Highlights: Study the Selenium speciation in paddy soil, explore the migration and transformation of selenium from soil to crops.