Introduction and BackgroundThe haor landscape (Figure 1) comprises a large, shallow tectonic depression in the northeastern part of Bangladesh that becomes inundated to a depth of 5 m or more during the monsoonal annual rainy season. Haor covers an area of approximately 2 million hectares (19,998 km 2 ) and supports a population of 19.37 million people (Chakraborty et al., 2021;Kamal et al., 2018). The haor basin is actively subsiding, and its hydrological, topographical, geomorphological, and socioeconomic features are distinctive as compared to other parts of Bangladesh (Chakraborty, Mondal, et al., 2012;IUCN, 2015). The geology of the haor basin consists of 13-20 km thick alluvial and deltaic deposits underlain by gneisses and granites, and the basin is bounded by the Shillong Plateau to the north (Figure 1), the Indo-Burman Range to the east, and the Indian Shield to the west. Non-calcareous, non-saline gray alluvium and acidic, alkaline clays are the most common soils within the basin (DBHWD, 2017), which is predominantly topographically flat but possesses some low hills that are covered with rainforest, tea and rubber plantations. The haor is very close to the towns of Cherrapunji (Figure 1) and Mawsynram, which are considered to be the rainiest places in the world, with an average annual rainfall of 11,755 mm and an average rainfall of 1,700 and 7,400 mm in the pre-and post-monsoon seasons, respectively (Basher et al., 2018;Rahman et al., 2020). As a result, the haor region receives significant runoff from 23 small transboundary rivers, including the Surma-Baulai, Kalni-Kushiyara, and Kangsa-Dhanu rivers, which originate in the hill regions of neighboring India. Seventy percent of the total catchment area of these rivers depends on three Indian States: Meghalaya, Assam, and Tripura (CEGIS, 2012). This abundant runoff enables the annual flooding of the haor region (Figure 2) to depths of 5-7 m, and much of the area is thus characterized by regular yearly inundation.