黑龙江绥化大宗农作物硒含量特征及影响因素分析

通过对松嫩平原绥化地区农作物及根系土样品的研究,开展了土壤理化性质、总硒、有效硒、硒形态及农作物硒含量测试,结合统计学方法探究了研究区内主要农作物的样品硒水平差异及其影响因素。结果表明,农作物硒含量为0.002～0.096 mg/kg,土壤总硒含量为0.13～0.52 mg/kg,土壤有效硒含量为0.002～0.007 mg/kg,土壤硒以强有机态硒（31.52%）为主。土壤总硒与有机质相关性较高,与有效硒、氧化还原电位（Eh）相关性较低;土壤有效硒与pH显著正相关;农作物硒含量与土壤离子交换态硒、有效硒、pH、Eh和有机质均有不同程度的相关关系。不同作物对硒元素的富集机理不同,水稻对硒元素的富集能力明显强于玉米。该研究表明可通过一定程度人为控制的土壤特性使得土壤中的硒更有利于农作物吸收,以便使农作物中硒含量能够满足居民硒健康需求,同时该研究为解决地质背景因素引起的天然"缺硒"地区提供了可能的解决途径。

Characteristics and Influencing Factors of Selenium Content of Staple Crops in Suihua Area of Heilongjiang Province

The selenium content and influencing factors of staple crops in Suihua area of Songnen Plain were investigated by analyzing the physical and chemical properties of soil, the content of soil total selenium, available selenium, selenium speciation, and crop selenium. Statistical methods were used to explore the main factors affecting soil selenium content and crop selenium content. The results indicated that the content of selenium in crops ranged from 0.002 to 0.096 mg/kg, the content of total selenium in soil ranged from 0.13 to 0.52 mg/kg, and the content of available selenium in soil ranged from 0.002 to 0.007 mg/kg, strong organic selenium is the main form of soil selenium (31.52%). Correlation analysis showed that soil total selenium had a high correlation with organic matter, but a low correlation with available selenium and redox potential (Eh); soil available selenium was significantly positively correlated with pH; selenium content in crops had different degrees of correlation with soil ion-exchangeable selenium, available selenium, pH, Eh and organic matter. The enrichment mechanism of selenium in different crops was different. The enrichment ability of selenium in rice was significantly stronger than that in maize. The results showed that the Se content in soil could be better absorbed by crops through the artificially controlled soil characteristics, so that the Se content in crops could meet the health needs of residents. At the same time, the study provides a possible way to solve the natural "selenium deficiency" caused by geological background factors.