Using Organic Matter and pH to Estimate the Bulk Density of Afforested/Reforested Soils in Northwest and Northeast China  

作　　者：CHEN Yue HUANG Yao SUN Wenjuan 

机构地区：[1]State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences

出　　处：《Pedosphere》2017年第5期890-900,共11页土壤圈（英文版）

基　　金：supported by the National Basic Research Program of China (No.2014CB954004);the National Natural Science Foundation of China (No.31370492)

摘　　要：Regression models for predicting soil bulk density(BD) have usually been related to organic matter content, but it remains unknown whether soil acidity modifies this relationship, particularly for afforested/reforested soils. We measured soil BD along with organic matter content and pH in an afforested/reforested area in Northwest and Northeast China. Using these measurements, we parameterized and validated three BD models: the Adams equation, and exponential and radical models. Model validation showed that the Adams equation failed to predict the BD of the afforested/reforested soils, producing a large overestimation. Incorporation of soil pH into the Adams equation significantly improved its performance. The exponential and radical models parameterized by the measured data simulated soil BD quite well, particularly when soil pH was incorporated. However, incorporation of soil texture variables into these models did not improve model performance compared with the pH-modified models. This led to the conclusion that the Adams equation, exponential, and radical models with pH modification are applicable to afforested/reforested soils with various acidities.Regression models for predicting soil bulk density （BD） have usually been related to organic matter content, but it remains unknown whether soil acidity modifies this relationship, particularly for afforested/reforested soils. We measured soil BD along with organic matter content and pH in an afforested/reforested area in Northwest and Northeast China. Using these measurements, we parameterized and validated three BD models： the Adams equation, and exponential and radical models. Model validation showed that the Adams equation failed to predict the BD of the afforested/reforested soils, producing a large overestimation. Incorporation of soil pH into the Adams equation significantly improved its performance. The exponential and radical models parameterized by the measured data simulated soil BD quite well, particularly when soil pH was incorporated. However, incorporation of soil texture variables into these models did not improve model performance compared with the pH-modified models. This led to the conclusion that the Adams equation, exponential, and radical models with pH modification are applicable to afforested/reforested soils with various acidities.

关 键 词：Adams equation regression model soil bulk density soil organic carbon soil pH 

分 类 号：S714[农业科学—林学]