2.4 LULC change detection and analysis of spatial trend
A post– classification change detection technique is used to
determine changes in LULC categories between 2017 and 2019. This process
resulted in three change detection maps; (i) 2017– 2018; (ii)
2018– 2019; and (iii) 2017– 2019. These operation
helps defining changes in LULC which subsequently aid in assessing
forest degradation, caused by resettlement of Rohingya populations.
Earlier (e.g., 2017) and later (e.g., 2018) thematic maps are compared,
on a pixel– by– pixel basis, and transformation of
LULC categories is defined to compute changes from a specific land class
to other classes (e.g., shrubs to Rohingya camps). The spatial trend is
then analyzed, based on the pattern of change between earlier and later
periods. Third order polynomial equation is used to analyze the spatial
change pattern. The resulting trend surfaces aid understanding the
direction of LULC change.