生态科学2023，Vol.42Issue(6)：51-62,12.DOI:10.14108/j.cnki.1008-8873.2023.06.006
基于分类变量定量化的玉树市土壤全碳制图
Soil total carbon mapping based on quantification of categorical variables in Yushu City
摘要
Abstract
The mapping of soil properties based on mathematical model has the characteristics of high efficiency,high speed and low cost,which makes up for the deficiency of spatial interpolation which ignores the categorical or qualitative variables such as soil type,vegetation type and environmental factors closely related to soil properties.In order to improve the accuracy of soil properties mapping and reduce the influence of uncertain factors,it is a new idea to make rational use of categorical variables in continuous soil properties mapping.In this study,total carbon mapping of soil in Yushu City,Qinghai Province was taken as an example,and weighted variables were constructed by soil type,geomorphic type and other categorical variables together with DEM and NDVI respectively,to explore the feasibility and practicability of weighted variables in soil properties mapping.The results show as follows.(1)The total carbon content of the soil in Yushu City is 19.60-120.55 g·kg-1,the average is 55.80 g·kg-1,the standard deviation is 19.22 g·kg-1,and the coefficient of variation is 34.44%,which is a medium degree of spatial variability.(2)The weighted variable model is superior to the similar model established by the digital elevation model,slope,aspect and other conventional variables.The overall importance of weighted variable is higher than that of conventional variable.The importance of weighted variable constructed by geological type,soil type,vegetation type and DEM is much higher than that of DEM itself.(3)The all-variable multiple regression model is the best model to predict soil total carbon content.The cumulative importance of the weighted variables in the all-variable multiple regression model is 0.55,and the prediction results are in line with the geosciences law and actual situation in the study area.In conclusion,weighted variables are a new way to make effective use of classified variables,which provides a new method for obtaining soil properties mapping variables,and its feasibility and practicability have been verified to some extent in this study.关键词
土壤属性/制图/加权变量/全碳/分类变量Key words
soil properties/mapping/weighted variables/total carbon/categorical variables分类
信息技术与安全科学引用本文复制引用
李润祥,何林华,高小红..基于分类变量定量化的玉树市土壤全碳制图[J].生态科学,2023,42(6):51-62,12.基金项目
国家自然科学基金项目(41550003) （41550003）
青海省科技厅自然科学基金项目(2021-ZJ-913) （2021-ZJ-913）
