区域尺度土壤-农作物体系营养元素铁的地球化学评价及膳食补铁区划

Geochemical Assessment of Iron Nutrition and Dietary Supplementation at a Regional Scale

铁(Fe)是人体健康必需的微量元素,人体Fe摄入不足或过量都会引起严重健康问题。目前区域尺度的土壤-农作物体系中Fe元素的预测及膳食摄入评估方面的研究较少。本文以四川省邻水县为研究区,采集了109套玉米与根系土样品以及6980件表层土壤样品,开展了土壤-农作物体系营养元素铁的地球化学评价及膳食补铁区划研究。结果表明,研究区表层土壤Fe含量范围为3070~198100 mg/kg,算术平均值为52370±1270 mg/kg,明显高于我国的土壤Fe背景值。研究区玉米籽实Fe含量范围为10.09~24.4 mg/kg,算术平均值为15.57±2.89 mg/kg,显著低于我国玉米中Fe含量均值。建立了玉米Fe生物富集系数预测模型,预测了玉米籽实Fe含量,并依据日均摄入Fe含量推荐值和居民膳食结构调查结果,给出了研究区玉米最佳Fe含量范围值为13.88~30.85 mg/kg。研究区膳食摄入评估结果表明,研究区大部分区域18~60岁人群Fe摄入较为充足;摄入缺乏区域零星分布,占研究区总耕地面积的3.87%。最后,给出了食用玉米不同地区需要补充Fe微量元素区划图,为研究区居民预防缺Fe引发的健康疾病提供了科学依据。

Iron(Fe)is one of the essential trace elements for the human body and plays a very important role,but insufficient or excessive intake of Fe will cause severe health problems.Diet is the main way of Fe intake,so the content of Fe in food directly affects human health,but there are few studies on the prediction of Fe in soil crop system and the evaluation of dietary intake at the regional scale.In this paper,109 sets of corn and root soil samples and 6980 topsoil samples were collected in Linshui County,Sichuan Province.We studied the spatial distribution characteristics of Fe in soil and crops and carried the geochemical assessment of iron nutrition and dietary supplementation.The results showed that the range of Fe content in the topsoil of Linshui county is 3.07-198.10 mg/g,and the arithmetic mean value is 52.37±1.27 mg/g.The average content of soil Fe in the study area is significantly higher than the background value of soil Fe in China.The arithmetic mean of Fe content in maize seeds in the study area was 15.57±2.89 mg/kg,which was significantly lower than the mean of Fe content in Maize in China.The prediction model of the Fe bioconcentration coefficient of maize was established to predict the Fe content of maize seeds.According to the recommended value of daily average Fe content recommended by the China Nutrition Society and the survey results of dietary nutrition of residents in the study area,the optimal Fe content range of Maize in the study area was 13.88-30.85mg/kg.Dietary intake in the study area was assessed;The results showed that most Fe intake was sufficient in this area;insufficient intake only sporadic distributed,accounting for 3.87%of the total cultivated land in the study area.Consuming locally produced corn cannot meet human Fe demand.Therefore,the zoning map of Fe trace elements in different areas of edible corn is given,which provides a scientific basis for residents in the study area to prevent health diseases caused by Fe deficiency.