西藏青稞产区土壤和籽粒硒含量调查研究

Investigation on Selenium Content in Soil and Hulless Barley Grains in Tibet

为明确西藏青稞产区土壤和籽粒硒含量及两者之间的关系,对西藏青稞主产区80个地点的青稞籽粒和土壤进行取样调查,研究不同青稞产区土壤全硒含量、有效硒含量和青稞籽粒硒含量及其成因。结果发现,西藏青稞产区土壤全硒含量范围在0.026~0.432mg·kg^-1,平均值为0.180mg·kg^-1;根据土壤全硒含量分类标准,缺硒土壤占49%,硒适量土壤占33%,富硒土壤占18%,富硒土壤主要分布在雅鲁藏布江以南地区。土壤有效硒含量范围在0.001~0.059mg·kg^-1,平均值为0.013mg·kg^-1。青稞籽粒硒含量范围在0~0.098mg·kg^-1,平均值为0.011mg·kg^-1;根据籽粒硒含量分类标准,其中90%属于硒缺乏。青稞主产区土壤全硒含量与土壤有效硒含量之间及二者与青稞籽粒硒含量之间均呈显著正相关关系,说明土壤全硒和有效硒含量可作为衡量青稞富硒潜力的有效指标。土壤有效硒每增加0.01mg·kg^-1,籽粒硒含量增加0.0144mg·kg^-1。本结果有助于西藏富硒土壤资源的合理开发、富硒青稞等农作物生产。

In order to clarify the relationship between total and available selenium(Se)in soil and Se in hulless barley grains in different production regions in Tibet,an investigation was conducted by sampling hulless barley and soil from 80 sites.The results showed that the soil total Se content ranged from 0.026 mg·kg^-1to 0.432 mg·kg^-1,with an average of 0.180 mg·kg^-1.According to the classification standard of total selenium content in soil,49%of them are selenium deficient soil,33%of them are selenium moderate soil,18%of them are selenium rich soil and mainly distributed in the south of Yarlung Zangbo River.The content of available Se in soil ranged from 0.001 to 0.059 mg·kg^-1,with an average value of 0.013 mg·kg^-1.The content of Se in barley grains ranged from 0 to 0.098 mg·kg^-1,with an average value of 0.011 mg·kg^-1.According to the classification standard of selenium content in barley grains,90%of them belonged to selenium deficiency.There was a significant positive correlation between the total selenium content and the available selenium content in soil and the grain selenium content of hulless barley in the main production area,which indicated that the total selenium and the available selenium content of the soil could be used as the effective indicators to measure the selenium potential of hulless barley.For every 0.01 mg·kg^-1increase of available Se in soil,the content of selenium in grain was increased by 0.0144 mg·kg^-1.The results are helpful for the rational development of selenium rich soil resources and the production of selenium rich hulless barley and other crops in Tibet.