GIS支持下豫东地区土壤野外采样布点方法探索

Sampling point arrangement based on GIS in eastern Henan Province

摘要:

以河南省通许县潮土区中低产田为例，介绍了一种GIS支持下的土壤野外采样布点方法，并对所取得的结果进行了讨论。根据要求覆盖研究区中低产田潮土的面积、涵盖所有土种类型、表层采样与剖面采样相结合、网格点与类型控制点相结合等原则，确定采用2 km×2 km网格布点方法。室内初步布点157个，涵盖了研究区16种土种类型，其中普通网格点141个，类型网格采样点6个，类型参考采样点10个。将布点图层与土壤图进行叠加分析，建立了空间数据库，完善布点属性表，作为野外精确采样的依据。实际采集普通网格点135个，剖面点15个。将室内布点与实际采样点位信息在数据库中分层管理，方便查询与更新。特别在剖面采样过程中发现实际采样与第二次土壤普查土种图比较，存在某些差异，应该根据实际采样诊断土壤类型并在GIS界面修正原始土壤分布图，将此改动作为建议提出，以便完善当地的土壤图。

Abstract:

A method of soil sampling point arrangement based on GIS based in Tongxu County, eastern Henan Province was conducted after some basic rules such as covering the studied soil and its species, combining surface and profile soil sampling points together and integrating grid points and soil type control points. 2 km × 2 km grids were created for arranging 157 soil sampling points including 141 ordinary and 6 type control grid spots, as well as 10 type control reference points, matching all the 16 soil types of the region. The layer of samples was overlaid with the soil map to establish a database of soil sampling point attributes and spatial patterns by which 135 topsoil sites and 15 profiles were actually collected. It is a more convenient way to search and update the soil information by layer-managing the soil sampling points in the database, for instance, some changes since the 2nd general national soil survey during sampling in 1980’s have taken place so that it is needed to diagnose the soil type and improve the initial soil map.