Application of Remote Sensing to Study Forest Encroachment in Tai Rom Yen National Park, Surat Thani Province

Abstract

Conflicts over land use involving communities surrounding protected forests are escalating into violence, as evidenced by increasing encroachment and the illegal possession of forest land. Tai Rom Yen National Park in Surat Thani province, Thailand faces problems of encroachment and illegal land possession. An inspection revealed 895 cases of encroachment from fiscal year 2006 to the present, covering an area of 1,226.39 hectares. The current study analyzed land use patterns in 2002, 2014 and 2022 and land use changes during 2002–2022 using Ortho-MOAC and Landsat 8 OLI satellite imagery. Visual interpretation techniques were implemented to identify traces of encroachment and to detect land use changes affecting forest areas in Tai Rom Yen National Park.

Based on the results, land use in the years 2002, 2014 and 2022 predominantly involved forest areas accounting for 83.79 %, 80.89 % and 80.69 %, respectively. Land use changes increased between 2002–2014 and 2014–2022 in agricultural, community, buildings, and water bodies areas by 17.68, 19.11 and 19.11%, respectively, and during 2014-2022, they increased by 1.54, 0.34 and 0.34 %, respectively. However, there were decreases in forest and miscellaneous areas by 3.35 % and 56.72 %, respectively, while during 2014–2022 these two types decreased by 0.36 % and 3.43 %, respectively. During 2002 and 2014 there were 4,623.18 hectares of land encroachment due to forest and agriculture. For the period between 2014 and 2022, 5,945.14 hectares of land were encroached due to agriculture and forest. The findings of this study should guide further investigation and monitoring of signs of encroachment in forest areas to help address the problem of forest encroachment.