摘要
【目的】探究土壤属性不相似性对于土壤转换函数预测的不确定性及误差的影响,并识别土壤转换函数预测的不确定成分的主要来源。【方法】以田间持水率(θ-300)和凋萎含水率(θ-15000)为研究对象,基于不同性质(相似或不相似)的数据集对土壤转换函数的不确定性进行分析;并采用拉丁超立方抽样和Bootstrap方法对不确定性来源贡献进行分析。【结果】无论θ-300或θ-15000,基于相似数据集建立的PTFs模型模拟性能有所提升,但效果较不明显。从不确定成分的主要贡献来看,对于θ-300,无论是基于相似还是不相似数据集,模型输入引起的不确定性贡献较大;但对于θ-15000,基于不相似数据集建立的PTFs则相反,即模型参数不确定性对模拟预测结果的影响占比较大,原因主要在于θ-15000往往具有较小的空间变异特征,因此其输入不确定性通常都较小。【结论】在针对农区构建PTFs预测田间持水率这一常数特征时,控制土壤样本理化性质的相似性有助于减少构建模型模拟结果的不确定性;而构建PTFs预测凋萎含水率时,则样本采集对模拟结果不确定性无明显影响,模拟结果的不确定性主要由构建模型的模型参数控制。
【Background】Many studies have generally applied the soil water content predicted by PTFs directly to numerical simulation.However,the uncertainty of PTFs prediction and its uncertainty have important impact on simulation results.So the similarity of soil characteristics has great influence on the construction of Pedotransfer functions(PTFs)and the uncertainty of their simulation predictions.【Objective】The objective of this paper is to explore the impact of soil properties dissimilarity on the uncertainty of PTFs,and to identify the main sources of uncertainty of PTFs.【Method】Usedθ-300 andθ-15000 as the research object,based on the data sets of different properties to analyze the uncertainty of the PTFs;This study used the Latin Hypercube Sampling and Bootstrap methods to analyze the sources of uncertainty.【Result】Forθ-300 andθ-15000,the simulation performance of PTFs based on similar data sets are improved,but it is not obvious.From the main sources of uncertainty,forθ-300,whether based on similar or dissimilar datasets,the uncertainty caused by input uncertainty was more important;but forθ-15000,the impact of parameter uncertainty is relatively larger than the input uncertainty.The main reason is thatθ-15000 data set tends to have smaller spatial variability characteristics.【Conclusion】We emphasized that when developing PTFs for predicting field capacity water content,it would be helpful to reduce modeling uncertainty by using similar soil samples only.While it might be worth putting much effort to model calibration and model construction when developing PTFs for predicting wilting point water content.
作者
王旭
朱金凤
STRAUSS Peter
张浩
王盛萍
WANG Xu;ZHU Jinfeng;STRAUSS Peter;ZHANG Hao;WANG Shengping(North China Electric Power University,College of Environmental Science and Engineering,Beijing 102206,China;Key Laboratory of Resources and Environmental Systems Optimization of Ministry of Education,Beijing 102206,China;Federal Agency for Water Management,Institute for Land and Water Management Research,Pollnbergstrasse 1,A-3252 Petzenkirchen,Austria)
出处
《灌溉排水学报》
CSCD
北大核心
2020年第S01期113-116,共4页
Journal of Irrigation and Drainage
