{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T06:15:55Z","timestamp":1762409755333,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,5,27]],"date-time":"2020-05-27T00:00:00Z","timestamp":1590537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U1901601"],"award-info":[{"award-number":["U1901601"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangdong Province Agricultural Science and Technology Innovation and Promotion Project","award":["No. 2019KJ102"],"award-info":[{"award-number":["No. 2019KJ102"]}]},{"name":"Guangdong Provincial Science and Technology Project of China","award":["2017B030314155"],"award-info":[{"award-number":["2017B030314155"]}]},{"name":"Qinghai Provincial Science and Technology Project of China","award":["2019-HZ-801"],"award-info":[{"award-number":["2019-HZ-801"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>There has been substantial research for estimating and mapping soil moisture content (SMC) of large areas using remotely sensed images by developing models of soil thermal inertia (STI). However, it is still a great challenge to accurately estimate SMC because of the impact of vegetation canopies and vegetation-induced shadows in mixed pixels on the estimates. In this study, a new method was developed to increase the estimation accuracy of SMC for an irrigated area located in YingKe of Heihe, China, using ASTER data. In the method, an original model of estimating bare STI was modified by decomposing a mixed pixel into three components, bare soil, vegetated soil, and shaded soil, as well as extracting their fractions using a spectral unmixing analysis and then deriving their fluxes. Moreover, the 90 m spatial resolution thermal images were scaled down to the 15 m spatial resolution by data fusion of a discrete wavelet transform (DWT) and re-sampling using the nearest neighbor method (NNM). The modified model was compared with the original model based on the mean absolute error (MAE) and relative root mean square error (RRMSE) between the SMC estimates and observations from 30 validation soil samples. The results indicated that compared to the original model based on the parallel dual layer, the modified STI model based on the serial dual layer statistically significantly decreased the MAE and RRMSE of the SMC estimates by 63.0\u201363.2% and 63.0\u201363.5%, respectively. The 15 m spatial resolution thermal bands obtained by the DWT data fusion provided more detailed information of SMC but did not significantly improve its estimation accuracy than the 15 m spatial resolution thermal bands by re-sampling using NNM. This implied that the novel method offered insights on how to increase the accuracy of retrieving SMC estimates in vegetated areas.<\/jats:p>","DOI":"10.3390\/rs12111719","type":"journal-article","created":{"date-parts":[[2020,5,28]],"date-time":"2020-05-28T12:36:58Z","timestamp":1590669418000},"page":"1719","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Improving Estimation of Soil Moisture Content Using a Modified Soil Thermal Inertia Model"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5334-2202","authenticated-orcid":false,"given":"Zhenhua","family":"Liu","sequence":"first","affiliation":[{"name":"College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Li","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4892-9698","authenticated-orcid":false,"given":"Yiping","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5419-4547","authenticated-orcid":false,"given":"Guangxing","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China"},{"name":"Department of Geography and Environmental Resources, College of Liberal Arts, Southern Illinois University Carbondale (SIUC), Carbondale, IL 62901, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yueming","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China"},{"name":"Guangdong Provincial Key Laboratory of Land Use and Consolidation, South China Agricultural University, Guangzhou 510642, China"},{"name":"Guangdong Province Engineering Research Center for Land Information Technology, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Construction Land Transformation, Ministry of Land and Resources, South China Agricultural University, Guangzhou 510642, China"},{"name":"College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1362","DOI":"10.1016\/j.jhydrol.2014.09.012","article-title":"Interactions of soil water content heterogeneity and species diversity patterns in semi-arid steppes on the Loess Plateau of China","volume":"519","author":"Wu","year":"2014","journal-title":"J. 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