The study area belongs to Savar and Dhamrai upazilas of Dhaka district. Savar upazila, with the elevation of 03-20 meter, is located in 23°44'45.1"-24°01'56.5"N and 90°11'11.4"-90°21'18.8" and Dhamrai upazila, with the elevation of 04-15 meter, is situated in 23°49'42.5"-24°02'38.6"N and 90°00'18.1"-90°14'45.4"E (https://elevation. maplogs.com; www.google.com/maps; http://dhaka.gov.bd). Though, the topography of Savar-Dhamrai region is plain to irregularly elevated and the height of land gradually increases from the east to the west and south to the north, the sampling sites of this study, composed of about 380 hectares of land, were confined to the mostly homogenous plain and fallow land areas of the region harboring different functional and abandoned brickfields The land of Savar- and Dhamrai region is composed of alluvium soil of the Pleistocene period (http://dhaka.gov.bd). The main rivers crossing this region are Dhaleshwari, Bangshi, Turag and Karnatali, and other rivers include Kolmai, Gazikhali, and Buriganga. These rivers are mostly polluted by industrial and sewerage wastes and residues of insecticides or herbicides etc. The soil of this region consists of heterogeneous assortment of silt, sand, clay, and gravel and often contains a good deal of organic matter due to which the land of the area is very fertile. The crest soils are represented by brownish grey, dark grey- and grey fine sandy loam soil. Consistency of dry soil is hard, moist soil is slightly firm to friable, while nature of wet soil is slightly sticky or plastic (Hossain et al., 2003). This region has a hot, wet and humid tropical climate, monthly humidity varies from 39% in January-February up to 92% in July-August, temperature ranges from 13°C in January-December to 39ºC in April-May and total rainfall from 0.6 mm in November-December to 350.80 mm in June-July (www.worldweatheronline.com). Specimens Collection and Preservation: About five hundred fresh specimens representing different taxa were collected from various habitats through the field trips conducted throughout the study area covering different seasons. The specimens were collected only from the healthy twigs with bud, flowers and fruit. The collected specimens were dried and processed using standard herbarium techniques (Bridson & Forman, 1989; Singh & Subramaniam, 2008). The voucher specimen of each taxon was selected considering the best representation of the vegetative and reproductive characters. All relevant field information, viz. collection date, locality, habit, habitat, stem height, size, shape, color and odor of the flowers and/or fruits, phenology, distribution, and uses etc. were recorded in the notebook. The dried and mounted specimens are deposited in Jahangirnagar University Herbarium (JUH). In order to assess the existing plant species diversity in different brickfield areas, quantitative field data were collected through quadrat sampling following the standard quadrat method (Braun-Blanquet, 1932; Raunkiaer, 1934; Cottam et al., 1953; Cottam & Curtis, 1956; Krebs, 1989). The standard size (1m²) of the quadrat was determined following the ‘Species Area Curve’ (Cain, 1938; Braun-Blanquet, 1964). Specimens Examination and Identification: All plant specimens were preliminarily identified through consulting the experts and matching with relevant voucher specimens preserved at Jahangirnagar University Herbarium (JUH). Taxonomic identification of the specimens were confirmed through matching them with the relevant type images available in the websites of different international herbaria (K, P, G), voucher specimens housed in Bangladesh National Herbarium (DACB), and respective taxonomic descriptions and keys available in standard taxonomic literature (Hooker, 1872-1897; Prain, 1903; Nasir & Ali, 1980-2005; Wu et al., 1999-2013; Siddiqui et al., 2007; Smitinand & Larsen, 1975, 1989; Ahmed et al., 2008-2009; Watson et al., 2011; Flora of North America Editorial Committee, 1993-2014). Information on different taxa and their distribution in Bangladesh were verified following Khan (1972-1987), Khan & Halim (1987), Siddiqui et al. (2007) and Ahmed et al., (2008-2009). Nomenclatural Information Collection: The updated nomenclatural information of all identified taxa was verified through consulting recent taxonomic publications (Nasir & Ali, 1980-2005; Wu et al., 1999-2013; Watson et al., 2011) and nomenclatural databases (IPNI, 2019; The Plant List, 2013; TROPICOS, 2020). The local name/s of plant species were based on Huq (1986), Pasha & Uddin (2013) and interviews with the local people. The angiosperm families are arranged following the classification system of Cronquist (1981), whereas the families of pteridophytes according to the classification system of Pichi (1977). All genera and species are arranged alphabetically.