Thirty-Year Dynamics of LULC at the Dong Thap Muoi Area, Southern Vietnam, Using Google Earth Engine

Nguyen An Binh 1 , Huynh Song Nhut 1 , Nguyen Ngoc An 1 , Tran Anh Phuong 1 , Nguyen Cao Hanh 1 , Giang Thi Phuong Thao 1 , The Trinh Pham 2 , Pham Viet Hong 3 , Le Thi Thu Ha 4 , Dieu Tien Bui 5,* and Pham Viet Hoa 1

1 Ho Chi Minh City Institute of Resources Geography, Vietnam Academy of Science and Technology, Ho Chi Minh City 700000, Vietnam; nabinh@hcmig.vast.vn (N.A.B.); hsnhut@hcmig.vast.vn (H.S.N.); nnan@hcmig.vast.vn (N.N.A.); taphuong@hcmig.vast.vn (T.A.P.); nchanh@hcmig.vast.vn (N.C.H.); gtpthao@hcmig.vast.vn (G.T.P.T.); pvhoa@hcmig.vast.vn (P.V.H.)

2 Dak Lak Department of Science and Technology, Buon Ma Thuot City, Dak Lak 630000, Vietnam; trinhkhcn@yahoo.com

3 Institute of Marine Geology and Geophysics, Vietnam Academy of Science and Technology, Hanoi 100000, Vietnam; hc18052001@yahoo.com

4 Department of Surface Mining, Hanoi University of Mining and Geology, Bac Tu Liem District, Hanoi 100000, Vietnam; lethithuha@humg.edu.vn

5 GIS Group, Department of Business and IT, University of South-Eastern Norway, N-3800 Bø i Telemark, Norway

* Correspondence: dieu.t.bui@usn.no

Abstract:

The main purpose of this paper is to assess the land use and land cover (LULC) changes for thirty years, from 1990–2020, in the Dong Thap Muoi, a flooded land area of the Mekong River Delta of Vietnam using Google Earth Engine and random forest algorithm. The specific purposes are: (1) determine the main LULC classes and (2) compute and analyze the magnitude and rate of changes for these LULC classes. For the above purposes, 128 Landsat images, topographic maps, land use status maps, cadastral maps, and ancillary data were collected and utilized to derive the LULC maps using the random forest classification algorithm. The overall accuracy of the LULC maps for 1990, 2000, 2010, and 2020 are 88.9, 83.5, 87.1, and 85.6%, respectively. The result showed that the unused land was dominant in 1990 with 28.9 % of the total area, but it was primarily converted to the paddy, a new dominant LULC class in 2020 (45.1%). The forest was reduced significantly from 14.4% in 1990 to only 5.5% of the total area in 2020. Whereas at the same time, the built-up increased from 0.3% to 6.2% of the total area. This research may help the authorities design exploitation policies for the Dong Thap Muoi’s socio-economic development and develop a new, stable, and sustainable ecosystem, promoting the advantages of the region, early forming a diversified agricultural structure.

Keywords: land use and land cover; remote sensing; Dong Thap Muoi; Vietnam