全国秸秆产生量抽样调查草谷比测定误差分析

张恒敢 顾克军 许博

摘要 基于第二次全国污染源普查中秸秆产生量抽样调查的流程和试验方法，分析了样品在不同阶段的干物质质量变化和含水率变化情况，以及这些变化对草谷比计算误差的影响，推导出基于调查流程的草谷比计算公式，分析了草谷比计算误差的来源，并据此提出减小误差的改进方案。试验结果表明，调查流程中草谷比测定误差影响因素多，来源复杂，对误差影响较大的是样品运输储藏阶段和最后的烘干阶段。运输储藏阶段可通过严格的保水措施减小误差，烘干测试阶段，水稻、小麦的误差较小，大豆、油菜的误差较大。根据理论推导和试验测定结果，提出基于干物质重量的调查方法（干物质法），通过增加2次精确的称量过程直接计算出草谷比。这种方法不仅能够减少误差，还因为不需要保持全水分，可以降低包装、运输、储藏成本。

关键词 污染源普查; 草谷比; 干燥模型

中图分类号 C81 文献标识码 A

文章编号 0517-6611（2020）14-0048-05

doi：10.3969/j.issn.0517-6611.2020.14.014

Abstract Based on the process and test method of straw production sampling survey in the second national pollution source survey， the dry matter quality change and moisture content change of straw and grain samples in different stages， as well as the influence of these changes on the calculation error of straw to grain ratio were analyzed. The calculation formula of straw to grain ratio was derived， and error sources were analyzed， and the error reduction solution was also proposed.There are many factors influencing the error of straw to grain ratio in the investigation process， and the error sources are complex. The most important factors contributing to the error are the sample transportation stage， storage stage and the final drying stage. In the transportation and storage stage， the error can be reduced by water conservation. In the drying stage， the error for rice and wheat can be ignored， while that of soybean and rape cant be. According to theoretical derivation and the experimental measurement， an investigation method （dry matter method） based on the weight of dry matter was proposed in this paper， which can calculate the straw to grain ratio by adding two accurate weighing operations. This method can not only reduce the error， but also reduce the cost of packaging， transportation and storage， because of that there is no need to keep full moisture in the flow.

Key words Polution source survey;Straw to grain ratio;Drying model

2016年10月26日，国务院印发《关于开展第二次全国污染源普查的通知》，决定于2017年12月31日起开展第二次全国污染源普查[1]。根据《全国污染源普查技术规定》，秸秆产生量抽样调查是第二次全国污染源普查的内容之一。秸秆产生量调查方法是通过对不同作物种类、不同区域的秸秆草谷比进行测定，结合普查和统计数据，测算农作物秸秆产量[2-3]。农业农村部组织全国多地农业行政、生产单位、科研部门进行了大规模的秸秆资源调查，秸秆产生量抽样调查为主要任务。……