区域性稻谷采样方案的优化  

Optimization of Regional Rice Sampling Scheme

作　　者：张洁琼 陈曦 伍燕湘 田巍 周明慧 朱琳 王松雪 邵懿 Zhang Jieqiong;Chen Xi;Wu Yanxiang;Tian Wei;Zhou Minghui;Zhu Lin;Wang Songxue;Shao Yi(Academy of National Food and Strategic Reserves Administration,Beijing 100037;China National Center for Food Safety Risk Assessment,Beijing 100022)

机构地区：[1]国家粮食和物资储备局科学研究院,北京100037 [2]国家食品安全风险评估中心,北京100022

出　　处：《中国粮油学报》2023年第2期22-28,共7页Journal of the Chinese Cereals and Oils Association

基　　金：“十三五”国家重点研发计划(2019YFC1605301-2,2019YFC1605200,2019YFC1605202)。

摘　　要：污染物监测调查工作的基础前提是采样,为探索稻谷中重金属污染调查的最佳采样量和布点方法,对研究区域内稻谷中重金属,总As、iAs、Cd、总Hg、Pb的含量进行采样分析,并利用经典统计学和分层抽样技术对该区域水稻中重金属的空间变异性和合理采样方案进行了研究。结果表明:研究区域糙米中6种重金属含量均呈对数正态分布,且平均值均低于国家限量。采用半方差函数拟合,总As、iAs、Cd、Pb均符合高斯模型,且决定系数均达到0.815以上,呈现中等或以上程度的空间相关性。比较经典统计学和分层抽样两种方法,得出以土壤类型对应的稻谷种植面积分层方法可减少约46.6%的采样数量,大幅降低采样及分析成本。以半方差函数拟合情况作为最优样点布局准则,得出最优采样布局,经描述性统计、概率分布和半方差函数等验证采样方案对于研究区域糙米中总As、iAs、Cd、Pb元素的适应性。Sampling is the basic premise of pollutant monitoring and investigation. The contents of Cr, total As, iAs, Cd, total Hg and Pb in rice in a studied city in Hunan Province was sampled and analyzed in the present study in order to explore the optimal sampling amount and location method for investigation of heavy metal pollution in rice. Classical statistics and stratified sampling techniques were used to study the spatial variability and reasonable sampling scheme of heavy metals in rice in this region. The results showed that the contents of six heavy metals in study area brown rice showed lognormal distribution, and their average values were lower than the national limits. The concentrations of total As, iAs, Cd and Pb in brown rice all fit the Gaussian model. Also, the determination coefficients were above 0.815, showing moderate or above spatial correlation. By comparing the two methods of classical statistics and stratified sampling, it was found that the stratified method of rice planting area corresponding to soil type can reduce the number of samples about 46.6%, and significantly reduced the cost of sampling and analysis. The fitting condition of semi-variance function was used as the optimal sampling layout criterion to obtain the optimal sampling layout. The adaptability of sampling scheme to total As, iAs, Cd, and Pb elements in brown rice in the study area was verified by descriptive statistics, probability distribution and semi-variance function and so on.

关 键 词：重金属 统计学 采样 半方差函数 

分 类 号：P628.2[天文地球—地质矿产勘探] X56[天文地球—地质学]