Integrated Geographical Information System (GIS) and Remote Sensing for Soil Erosion Assessment by Using Universal Soil Loss Equation (USLE): Case Study in Son La Province

Son La is a mountainous province in the North of Vietnam with complicated terrain, high slope, rugged and fragmentation terrain. Mountainous land occupies 92% of the natural area, in which land with sloping over 15 degrees occupies 67% of natural land area, erosion is the main cause of soil degradation. The result shows that the average soil loss due to erosion in Son La province is 30.04 tons/ha/year. On the level of erosion, soil erosion is very low (g 50 tons/ha/year) accounts for a large proportion with the area and the percentage respectively is 51,223.60 ha, occupying 38.74% of the natural area and 45,424.45 ha accounting for 34.36% of the natural area. Then there is low level (1-5 tons/ha/year) with an area of 19,462.78 hectares, accounting for 14.72% of the natural area. Moderate (5-10 tons/ha/year) and high (10-50 tons/ha/year) levels account for a small proportion of 7,488.48 hectares, accounting for 5.66% and 8,611.23 hectares, accounting for 6.51%, respectively, of the natural area. The combination of remote sensing, geographic information system and RUSLE with available data can calculate soil erosion, spatial distribution, and area, initial testing of the model results and actual observation shows the disparity low (<4,3%). Keywords Soil erosion, Soil degradation, Remote sensing, GIS, Terrain, Son La. References [1] Nguyễn Tử Siem, Thai Phien, Đất đồi nui Việt Nam - Thoai hoa va phục hồi, NXB Nong nghiệp, Ha Nội, 1999. [2] Nguyễn Trọng Ha, Xac định cac yếu tố gây xoi mon va khả năng dự bao xoi mon tren đất dốc, Luận an Tiến sỹ, Trường Đại học Thủy lợi, Ha Nội, 1996. [3] Nguyễn Quang Mỹ, Xoi mon đất hiện đại va cac biện phap phong chống, NXB bản Ðại học Quốc Gia Ha Nội, Ha Nội, 2005. [4] Trần Quốc Vinh, Đặng Hung Vo va Đao Châu Thu, Application of Remote Sensing and Geographic Information System in evaluating soil erosion. A Case study in Tam Nong district, Phu Tho province, Jounal of Science and Development 9(5) (2011) 823-833. [5] L.Q. Doanh, H.D. Tuan and A. Chabanne A, Upland Agro-Ecology Research and Development in Vietnam, Building an Agro-Ecological Network through DMC in Southeast Asia, Vientiane, Lao, 2005. http://open library.cirad. fr/ files/2/241_1141426824. pdf (accessed 16 June 2018). [6] Jarbou A. Bahrawi, Mohamed Elhag, Amal Y. Aldhebiani, Hanaa K. Galal, Ahmad K. Hegazy, Ebtisam Alghailani, Soil Erosion Estimation Using Remote Sensing Techniques in Wadi Yalamlam Basin, Saudi Arabia, Advances in Materials Science and Engineering Article ID 9585962 (2016) 8 pages. http://dx.doi.org/10.1155/ 2016/9585962. [7] Trương Văn Cảnh, Nghien cứu ảnh hưởng xoi mon đất của lưu vực Song Cu Đe đến sản xuất nong nghiệp, Bao cao tổng kết đề tai khoa học, Đại học Đa Nẵng, Đa Nẵng, 2014. [8] D.K. McCool, L.C. Brown, G.R. Foster, C.K. Mutchler, L.D. Meyer, Revised Slope Steepness Factor for the Universal Soil Loss Equation, Transactions of the ASAE. 30(5) (1987) 1387-1396. https://doi.org/10.13031/2013.30576. [9] K.G. Renard, G.R. Foster, G.A. Weesies, D.K. McCool, D. C. Yoder, Predicting Soil Erosion by Water: A Guide to Conservation Planning With the Revised Universal Soil Loss Equation, U.S Government Printing Office, Washington DC, 1997.https://www.ars. usda.gov/ARSUserFiles/64080530/rusle/ah_703. pdf (accessed 12 June 2018). [10] Mepas.pnnl. gov, 5.3. 2 Soil Erodibility Factor. https://mepas.pnnl. gov/mepas/formulations/source_term/5_0/5_32/5_32. html/, 2018 (accessed 12 June 2018). [11] V.L. Durigon, D.F. Carvalho, M.A.H. Antunes, P.T. S. Oliveira, M.M. Fernandes, NDVI time series for monitoring RUSLE cover management factor in a tropical watershed, International Journal of Remote Sensing 35(2) (2014) 441-453. https://doi.org/10.1080/01431161.2013. 871081. [12] USGS, https://earthexplorer.usgs. gov/, 2018(accessed 15 June 2018). [13] Vezina Karine, Bonn Ferdinand and Cu Pham Van, Agricultural landuse patterns and soil erosion vulnerability of watershed units in Vietnam’s northern highlands, Landscape Ecol. 21 (2006) 1311–1325. https://doi.org/10.1007/s 10980-006-0023-x. [14] Vo Đại Hải, Nghien cứu cac dạng cấu truc hợp lý cho rừng phong hộ đầu nguồn ở Việt Nam, Luận an tiến sỹ, Viện Khoa học Lâm nghiệp Việt Nam, Ha Nội, 1996. [15] Trung tâm Dữ liệu va Thong tin Đất đai, Số liệu va bản đồ Hiện trạng sử dụng đất năm 2015 của tỉnh Sơn La, Ha Nội, 2015. [16] X.H. Nguyen, A.H. Pham, Assessing Soil Erosion by Agricultural and Forestry Production and Proposing Solutions to Mitigate: A Case Study in Son La Province, Vietnam, Applied and Environmental Soil Science Volume 2018, Article ID 2397265 (2018) 10 pages. https://doi.org/10. 1155/2018/2397265.