天然富硒土地划定的富硒阈值

Selenium Threshold for the Delimitation of Natural Selenium-Enriched Land

提出适用全国的土壤富硒阈值是查明我国富硒土地资源和发展特色农业的关键.利用我国最近10 a采集的10222套大宗农作物根系土-作物籽实协同调查数据,基于大宗农作物-土壤线性模型和人群硒摄入量对富硒阈值进行初步估算探索,最终通过建立土壤富硒率和作物籽实富硒率协同分析模型,提出了适用全国的富硒阈值:水田土壤中总硒含量≥0.40μg·g^(-1)、旱地土壤中总硒含量≥0.30μg·g^(-1),并在全国13省进行可行性检验,该阈值的建立为中国地质调查局制定和颁布实施天然富硒土地划定与标识相关技术标准提供了有力支撑.

The nationwide Se-enriched threshold plays a key role in identifying China's selenium-enriched land resources and developing characteristic agricultural practices.In this study,we used the cooperative data of 10222 sets of crops and roots in China for the past 10 years with a systematic analysis of the selenium content characteristics of the soil and the status of selenium-enriched agricultural products.The preliminary estimates of the selenium-enriched threshold based on a bulk crop-soil linear model and population selenium-intake are presented.Finally,a collaborative analysis model of soil selenium-enrichment rate and crop seleniumenrichment rate is established,coming up with the nationwide Se-enriched threshold:total selenium≥0.40μg·g^(-1)in paddy soil,and total selenium≥0.30μg·g^(-1)in dryland soil.The threshold passed the feasibility test in 13 provinces,providing strong support for the China Geological Survey to formulate and promulgate this technical standard for the delimitation of the natural selenium-enriched land.