Application of isotopic information for estimating parameters in Philip infiltration model  

作　　者：Tao Wang Hai-li Xu Wei-min Bao 

机构地区：[1]PowerChina Chengdu Engineering Corporation Limited, Chengdu 610072, China [2]State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China

出　　处：《Water Science and Engineering》2016年第4期287-292,共6页水科学与水工程（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.51279057)

摘　　要：Minimizing parameter uncertainty is crucial in the application of hydrologic models.Isotopic information in various hydrologic components of the water cycle can expand our knowledge of the dynamics of water flow in the system,provide additional information for parameter estimation,and improve parameter identifiability.This study combined the Philip infiltration model with an isotopic mixing model using an isotopic mass balance approach for estimating parameters in the Philip infiltration model.Two approaches to parameter estimation were compared:(a) using isotopic information to determine the soil water transmission and then hydrologic information to estimate the soil sorptivity,and(b) using hydrologic information to determine the soil water transmission and the soil sorptivity.Results of parameter estimation were verified through a rainfall infiltration experiment in a laboratory under rainfall with constant isotopic compositions and uniform initial soil water content conditions.Experimental results showed that approach(a),using isotopic and hydrologic information,estimated the soil water transmission in the Philip infiltration model in a manner that matched measured values well.The results of parameter estimation of approach(a) were better than those of approach(b).It was also found that the analytical precision of hydrogen and oxygen stable isotopes had a significant effect on parameter estimation using isotopic information.Minimizing parameter uncertainty is crucial in the application of hydrologic models.Isotopic information in various hydrologic components of the water cycle can expand our knowledge of the dynamics of water flow in the system,provide additional information for parameter estimation,and improve parameter identifiability.This study combined the Philip infiltration model with an isotopic mixing model using an isotopic mass balance approach for estimating parameters in the Philip infiltration model.Two approaches to parameter estimation were compared:(a) using isotopic information to determine the soil water transmission and then hydrologic information to estimate the soil sorptivity,and(b) using hydrologic information to determine the soil water transmission and the soil sorptivity.Results of parameter estimation were verified through a rainfall infiltration experiment in a laboratory under rainfall with constant isotopic compositions and uniform initial soil water content conditions.Experimental results showed that approach(a),using isotopic and hydrologic information,estimated the soil water transmission in the Philip infiltration model in a manner that matched measured values well.The results of parameter estimation of approach(a) were better than those of approach(b).It was also found that the analytical precision of hydrogen and oxygen stable isotopes had a significant effect on parameter estimation using isotopic information.

关 键 词：ISOTOPIC INFORMATION Hydrologic INFORMATION PARAMETER estimation Philip INFILTRATION model RAINFALL INFILTRATION experiment 

分 类 号：P333[天文地球—水文科学] P339[水利工程—水文学及水资源]