A trustworthiness indicator to select sample points for the individual predictive soil mapping method (iPSM)

doi:10.1016/j.geoderma.2020.114440

	A trustworthiness indicator to select sample points for the individual predictive soil mapping method (iPSM)
	Liu, Jing 3,5; Zhu, A-Xing 2,4,5,6; Rossiter, David 1,2; Du, Fei 5; Burt, James 5
刊名	GEODERMA
	2020-08-15
卷号	373 页码:13
关键词	Digital Soil Mapping Sample reliability Prediction trustworthiness Prediction uncertainty Third law of geography
ISSN号	0016-7061
DOI	10.1016/j.geoderma.2020.114440
通讯作者	Zhu, A-Xing(azhu@wisc.edu)
英文摘要	Observations of soil at georeferenced sample points are the indispensable input to digital soil mapping (DSM) models that relate soil properties and types to the soil-forming environment. Many existing DSM methods require soil samples to be collected following a pre-defined sampling pattern. This requirement is often not ma due to various operational reasons. The individual sample-based predictive soil mapping (iPSM) method has been developed to avoid this requirement. However, the prediction accuracy of iPSM depends heavily on the reliability of the known sample points used in prediction. Unreliable sample points are those with unreliable soil-environment relationship: the target soil property value and environmental covariate data are not correctly paired at the sample point location. Such unreliable sample points will lead to poorly constructed models and low prediction accuracy. This paper presents a new method to estimate the reliability of soil-environment relationship at each sample location and to evaluate the trustworthiness of prediction at each unvisited location. Under the assumption that sample points with similar environmental conditions have similar soil property values, the method first identifies the sample points that are environmentally similar to the sample point to be evaluated, then uses their agreement on the targeted soil property to evaluate the reliability of soil-environment relationship at the sample point. The effectiveness of the method was assessed in a case study located in Anhui Province in China to map soil organic matter content (SOM, %) in the topsoil. When the reliability threshold increased from 0.5 to 0.8, more unreliable sample points are excluded from prediction: 41% of total sample points were excluded when the threshold was set to 0.5, and 88% were excluded when the threshold was set to 0.8. As a result, less unknown area could be predicted - only nine validation points were predictable with the 0.8 reliability threshold. However, the prediction accuracy was improved: the root mean squared error, RMSE, decreased from 1.37% to 0.63%, and R-2 increased from 0.21 to 0.98. Prediction trustworthiness at each unvisited location was also produced along with prediction accuracy, which was negatively related to the absolute prediction residuals. This study shows that the reliability of individual sample points is an important determinant of the prediction accuracy of the iPSM method. When applying iPSM method, an optimal trade-off between prediction accuracy and completeness of the predicted map needs to be found by adjusting the reliability threshold on the sample points used in prediction.
资助项目	National Natural Science Foundation of China[41871300] ; National Natural Science Foundation of China[41431177] ; National Basic Research Program of China[2015CB954102] ; PAPD ; Outstanding Innovation Team in Colleges and Universities in Jiangsu Province ; Whitbeck Graduate Dissertator Award ; Vilas Conference Presentation Funding ; Vilas Associate Award ; Hammel Faculty Fellow Award ; Manasse Chair Professorship from the University of Wisconsin-Madison
WOS关键词	UNCERTAINTY ; PATTERNS
WOS研究方向	Agriculture
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000537626800001
资助机构	National Natural Science Foundation of China ; National Basic Research Program of China ; PAPD ; Outstanding Innovation Team in Colleges and Universities in Jiangsu Province ; Whitbeck Graduate Dissertator Award ; Vilas Conference Presentation Funding ; Vilas Associate Award ; Hammel Faculty Fellow Award ; Manasse Chair Professorship from the University of Wisconsin-Madison
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/159488]
专题	中国科学院地理科学与资源研究所
通讯作者	Zhu, A-Xing
作者单位	1.Cornell Univ, Sect Soil & Crop Sci, Ithaca, NY 14583 USA 2.Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Jiangsu, Peoples R China 3.Santa Mon Coll, Earth Sci Dept, Santa Monica, CA 90405 USA 4.Nanjing Normal Univ, Minist Educ, Key Lab Virtual Geog Environm, 1 Wenyuan Rd, Nanjing 210023, Jiangsu, Peoples R China 5.Univ Wisconsin, Dept Geog, 550 N Pk St, Madison, WI 53706 USA 6.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China
推荐引用方式 GB/T 7714	Liu, Jing,Zhu, A-Xing,Rossiter, David,et al. A trustworthiness indicator to select sample points for the individual predictive soil mapping method (iPSM)[J]. GEODERMA,2020,373:13.
APA	Liu, Jing,Zhu, A-Xing,Rossiter, David,Du, Fei,&Burt, James.(2020).A trustworthiness indicator to select sample points for the individual predictive soil mapping method (iPSM).GEODERMA,373,13.
MLA	Liu, Jing,et al."A trustworthiness indicator to select sample points for the individual predictive soil mapping method (iPSM)".GEODERMA 373(2020):13.