Application of integrated spatial analysis and NDVI for tree monitoring in reclamation area of coal mine.

Abstract

Reclamation, defined as one of the important processes in mining, is commonly conducted to regain the value of the land after natural resource extraction. The process involves many activities such as reforestation, remediation, and land transformation. Even supposing that those processes can be monitored, thus some of the progress in those activities cannot be numerically evaluated, especially for reforestation. Mae Moh mine, the largest coal mine in Southeast Asia, is in the early stage of reclamation where a large scale of reforestation must be accomplished. However, the monitoring and evaluation of the improvement of those areas are based on manual field observation which is time-consuming and inefficient. For a purpose of subsiding the conventional method, integrated spatial technology was assigned as the main tool in defining the effective indirect method for monitoring and evaluating the reforested area. In this study, the remote sensing techniques, based on satellite-images and multispectral-UAV, were compared to define the most appropriate data collecting method which will be assigned as the main tool for gathering the data over the reforestation area of Giant crepe-myrtle, Indian cork Tree, Laza wood, and Teak. These collected data were further analyzed into normalized difference vegetation index (NDVI) and used as the dependent variable for linear regression with significant parameters, affecting the growth of the reforested species. The results of the study defined that the suitable collecting method is the multispectral-UAV which can give %RSD of NDVI range from 16.58 to 40.75. In accordance with the analysis, the R2 of the regression modeling for each species ranged from 0.568 to 0.831, which can determine the feasibility of assigning the model for the indirect monitoring scheme for the reclamation.