Mapping and monitoring top-dying disease of the Heritiera fomes tree species in the Bangladesh Sundarbans.

The top dying of Sundari trees in the Sundarbans is a distressing ecological issue that demands our immediate attention. The Sundarbans, a UNESCO World Heritage site and one of the largest mangrove forests in the world is renowned for its unique biodiversity and crucial role in supporting the ecosystem of the region. However, the recent phenomenon of top dying in Sundari (H. fomes) trees has raised concerns about the long-term sustainability of this invaluable ecosystem. Examination of such trees reveals that the bark dies first and is followed by the death of sapwood. Occasionally rot of both sapwood and heartwood may occur simultaneously (Rahman, 1996). However, there is evidence that the disease syndrome was widespread or causing major losses prior to the early 1970s (Boa, 1988). According to preliminary estimates of the prevalence of the top-dying of H. fomes, over 17% of the stems in all forest types where H. fomes is a major species are moderately or severely impacted (Chaffey et al., 1985). Chowdhury (1988) estimated the mean annual timber loss, due to the disease to be 1.44 million cu. ft. of timber which is worth Taka 2000.00 million. As H. fomes exhibits ecological and height dominance in the Sundarbans, the loss of the species is likely to have a wider impact on the ecosystem as well as direct financial loss (Karim, 1988). Therefore, continuous monitoring of the top dying of H. fomes in the Sundarbans is important to safeguard this species. Remote sensing plays a crucial role in disease monitoring of trees by providing valuable information about the health and condition of forest ecosystems. Through the use of satellite imagery, aerial photography, and other remote sensing techniques, scientists and researchers can effectively detect, analyze, and monitor tree diseases over large areas and extended periods. So, this study has been proposed to monitor this disease through remote sensing technology.

• Research Project