remote sensing Article Rapid Invasion of Spartina alterniflora in the Coastal Zone of Mainland China: New Observations from Landsat OLI Images Mingyue Liu 1,2 , Dehua Mao 1,*, Zongming Wang 1,*, Lin Li 3, Weidong Man 1,2 , Mingming Jia 1 , Chunying Ren 1 and Yuanzhi Zhang 4,5,* 1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China;
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[email protected] (C.R.) 2 College of Mining Engineering, North China University of Science and Technology, Tangshan 063210, China 3 Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN 46202, USA;
[email protected] 4 Chinese University of Hong Kong, Center for Housing Innovations, Shatin, New Territories, Hong Kong, China 5 Chinese Academy of Sciences, Key Lab of Lunar Science and Deep-exploration, National Astronomical Observatories, Beijing 100101, China * Correspondence:
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[email protected] (Y.Z.); Tel.: +86-431-85542254 (D.M.) Received: 1 November 2018; Accepted: 28 November 2018; Published: 1 December 2018 Abstract: Plant invasion imposes significant threats to biodiversity and ecosystem function. Thus, monitoring the spatial pattern of invasive plants is vital for effective ecosystem management. Spartina alterniflora (S. alterniflora) has been one of the most prevalent invasive plants along the China coast, and its spread has had severe ecological consequences. Here, we provide new observation from Landsat operational land imager (OLI) images. Specifically, 43 Landsat-8 OLI images from 2014 to 2016, a combination of object-based image analysis (OBIA) and support vector machine (SVM) methods, and field surveys covering the whole coast were used to construct an up-to-date dataset for 2015 and investigate the spatial variability of S.