地表基质调查分层及分层测试指标体系设计与构建

Exploration on the Stratification of the Ground Substrate Survey and the Design and Construction of Its Testing Indicator System

地表基质是地球表层物质与能量循环的主要载体,地表基质调查是一项创新性工作,明确地表基质调查分层及分层测试指标是开展地表基质调查的基础。本文基于地表基质调查的内涵和目标定位,深入分析了多目标区域地球化学调查、全国第三次土壤普查和全国农用地土壤污染详查等调查深度和测试指标;利用近三年自然资源综合调查指挥中心在吉林省梨树县、辽宁省丹东市、黑龙江省哈尔滨市三个地表基质调查试点项目实测数据,运用变动系数法分析了不同地区地表基质层的地球化学元素垂向变化特征,结合表生地质作用(风化为主)最大深度、地表植被根系最大深度、浅层地下水位波动下限、基岩顶面深度等因素,将地表基质在垂向上大致分为三层:表层(0~2m)、中层(2~10m)和深层(10~20m),基岩埋深浅于20m则以揭露到基岩为准;表层(0~2m),称为生产层,包括支撑农业生产的耕作层,主要服务国家粮食安全,以收集资料为主;中层(2~10m),称为生态层,主要支撑植被生长和群落演替,服务国土空间开发保护与格局优化,是地表基质调查的重点;深层(10~20m),称为沉积层,主要研究地表基质从基岩—深层—中层—表层演替规律和特征,以部署少量工程控制为宜。基于地表基质分层调查意义,结合元素在垂向上的变化规律,提出4+N型地表基质分层测试指标体系,即4类必测指标和针对特殊工作需要的N类选测指标,以期加快推进地表基质调查标准化、规范化。

The ground substrate layer is the main carrier of the material and energy cycle of the earth’s surface.At present,it is essential to have a suitable ground substrate stratification and testing index system for conducting an effective ground substrate survey.Based on the pilot results of the ground substrate survey project in the past three years,and the links between ground substrate with Multi-Objective Regional Geochemical Surveys,the Third National Soil Census and the National Detailed Survey of Soil Pollution on Agricultural Land,the ground substrate can be vertically divided into three layers:the surface production layer(0-2m),the middle ecological layer(2-10m)and the deep sedimentary layer(10-20m).If the depth of the base layer is less than 20m,the ground substrate is exposed to the bedrock.The surface layer mainly serves the national food security,and mainly collects data;the middle layer focuses on territorial space planning,and is the focus of investigation;the deep layer is mainly to explore the ground substrate from bedrock-deep layer-middle layer-surface layer succession pattern,a small amount of engineering control is appropriate.The proposed vertical stratified test index system for ground substrate includes 4 required indices and N selected indices.The established stratification and stratification test index system of ground substrate can provide reference for standardizing the ground substrate survey and promote the high-quality development of the ground substrate survey.