Air-drying changes the distribution of Hedley phosphorus pools in forest soils  

作　　者：Jipeng WANG Yanhong WU Jun ZHOU Haijian BING Hongyang SUN Ji LUO Shengyan PU 

机构地区：[1]Key Laboratory of Mountain Surface Processes and Ecological Regulation,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,China [2]State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China

出　　处：《Pedosphere》2020年第2期272-284,共13页土壤圈（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.41630751,41401253 and 41471416)。

摘　　要：Hedley labile phosphorus(P)pools in soil tend to be several times larger than annual forest requirements,even in highly weathered soils characterized by P limitation.The discrepancy between plant and soil P status could be partly attributable to the frequently adopted air-drying pretreatment that tends to increase soil P solubility.In this study,the effects of air-drying on the distribution of Hedley P fractions were examined using soils collected under 4 forest types at Gongga Mountain,southwestern China.The results showed that the microbial biomass P(Pmic)in the organic horizon decreased markedly after air-drying.The concentrations of Hedley labile P in the air-dried samples were 31%–73%more than those in the field-moist samples.Consequently,the air-drying-induced increments of Hedley labile P pools in the surface soil horizons were 0.8–3.8 times the annual plant P requirements.The organic horizon was more susceptible to the air-drying-induced increases in Hedley labile P than the mineral horizon,probably because of the stronger release of Pmicand disruption of soil organic matter.The quality of P,indexed by the ratio of Hedley labile P to slowly cycling P,shifted in favor of the Hedley labile fractions after air-drying,further revealing that air-drying changed the distribution of Hedley P pools in forest soils.These indicated that the effects of air-drying could not be ignored when interpreting the discrepancy between the P status of plants and the Hedley labile P pools in forest soils.To more efficiently evaluate the P status in forest soils via the Hedley fractionation procedure,the use of field-moist soils is recommended.

关 键 词：Hedley FRACTIONATION labile PHOSPHORUS microbial biomass PHOSPHORUS phosphorous LIMITATION slowly CYCLING PHOSPHORUS soil pretreatment 

分 类 号：S714[农业科学—林学]