A PRELIMINARY INVENTORY OF ANGIOSPERMIC FLORA OF BAGATIPARA UPAZILA, NATORE, BANGLADESH

Preparation of the country's flora is very challenging until baseline information on the flora of all district or upazila is available. The purpose of this inventory was to record angiosperm plant species available in the different habitats of Bagatipara upazila, which is located in the eastern part of Rajshahi district. The traditional taxonomic method was applied for plant sample collection in different seasons of the year 2022 and the identification of the collected samples. This research resulted in the recording of a total of 377 species in 92 families. Among them, 310 species were from Magnoliopsida, and 67 were from Liliopsida. Asteraceae and Poaceae were the leading families of Magnoliopsida and Liliopsida, respectively. One-fourth of the total plant species were exotic, and more than half were valuable medicinal species. Artocarpus lacucha , Bridelia stipularis , Callicarpa longifolia , Eranthemum pulchellum , Oroxylum indicum , Potentilla supina , Sterculia foetida , and Terminalia arjuna were locally found rare. Threats such as climate change, expansion of arable land and pisciculture, use of herbicides, over exploitation, clearing brushwood, and unplanned construction activities have been identified. The present study concludes that the floristic composition of this area is still rich, though the area is facing some threats. Therefore, we strongly recommend adopting effective and adequate measures for sustainable conservation and monitoring of the biodiversity of this area.


Introduction
Information of floristic research is important for the sustainable use and conservation of plant resource as well as resource based-development in the respective area.Floristic research in a particular area provides valuable information about existing plant species in that area, such as, their habitat, uses, status, threats, and so on.Bagatipara is an upazila of North-Western district, Natore and adjacent to the warmer zone of Bangladesh.Both urban and semi-urban or rural areas are found in this upazila.It has mixed habitats and ecosystems such as agricultural fields, railway and road sides, fallow lands, gardens, grooves, thickets, canal or river banks and a little wet land which support luxuriant formation of plants especially flowering plants.Bangladesh is very rich in biodiversity due to its unique geographical location and seasonal variation.The flora of Bangladesh is thought to consist of approx.5000 species of angiosperms (Khan, 1977).Unfortunately, a number of plant species are disappearing day after day at an alarming rate due to anthropogenic disturbance such as habit destruction, over-exploitation, pollution, and invasion of exotic species.Apart from these, recent climate change conditions are becoming serious threats to the biodiversity of Bangladesh.Despite several floristic studies (Alam et al., 2006;Islam et al., 2009;Tutul et al., 2010;Uddin and Hassan, 2010;Arefin et al., 2011;Sarker et al., 2013;Uddin et al., 2013;Kona and Rahman, 2015;Uddin et al., 2015;Uddin and Abiadbullah, 2016;Mahmudah et al., 2017;Rahman et al., 2017;Khan et al., 2021;Islam et al., 2022) being conducted since the *Corresponding author, E-mail: zashim@du.ac.bd emergence of Bangladesh, the country's floristic exploration has not yet been completed.As a result, the floristic composition in most of the upazila or districts is still unknown or little known.As we know, so far a few work has been done by researchers or botanists in Natore district (Hasan et al., 2013;Sultana and Rahman, 2017;Hasan, 2020) focusing only medicinal plant species.But no comprehensive floristic research has been done in Bagatipara upazila before.Keeping this view in mind we decided to explore the floristic composition of Bagatipara upazila.The objectives of the current work is to formulate baseline data on the floristic composition in Bagatipara upazila along with other associated information that will contribute to understanding the flora of Bangladesh.

Data collections
This work was carried out from January 2022 to December 2022 to document and enlisting angiospermic taxa in different seasons and divers habitat of the study area.Repeated visits were done to every part of the study area and was collect specimen following conventional methods.Relevant floras (Ahmed et al., 2009;Uddin and Hassan, 2018), and published articles were consulted for specimen identification.All specimen were housed at Depertment of Botany, Rajshahi Government City College, Rajshahi.Various information was obtained through free interviews and informal conversation.The information regarding the endangered plants and their conservation has been gathered from local farmers, elderly and knowledgeable persons.Twenty five (21 men and 4 women) individuals were interviewed.Among them, 7 were of ages 20-40 years, 12 were 41-60 years and 6 were of ages more than 61 years.To arrange the collected families in this article, Cronquist's (1988) system was followed in the arrangement of the families, and the species under the same family were arranged alphabetically (Table 1).Besides that, some families have been sited according to APG IV system (Angiosperm Phylogeny Group.2016) which was not found in Cronquist (1988).Scientific names were mentioned according to POWO (Plants of the World Online).Local names were mentioned according to Pasha and Uddin (2013) and Huq (2019).Exotic plant species have been determined by consulting Ahmed et al. (2009), Dutta et al. (2015), Uddin et al. (2021) and Uddin et al. (2022).Medicinal plant species have been determined by consulting Uddin et al. (2022), Mitu et al. (2022) and Rifat et al. (2022).

Results and Discussion
From the study area, total 377 plant species (both wild and cultivated) have been collected and they were distributed under 92 families.For each species scientific name, bangla name, family name, habits, habitats, uses, status, origin and occurance were provided (Table 1).Magnoliopsida were represented by 310 species from 242 genera while Liliopsida comprising of 67 species from 49 genera.Earlier, Rahman et al. (2019) documented 216 species under 72 families and Khatun et al. (2022) reported 194 species under 72 families from adjacent Lalpur and Puthia Upazila respectively.Regarding the distribution of family, Magnoliopsida and Liliopsida consist of 75 and 17 family respectively.The leading family in Magnoliopsida was Asteraceae consisting of 31 species and other major families were Fabaceae (22), Acanthaceae (15) and Euphorbiaceae (15).In Liliopsida, Poaceae appeared as the largest family consisting of 22 species and the other major families were Cyperaceae (09) and Araceae (08).The largest genus in Magnoliopsida was Solanum bearing 8 species followed by Ficus and Euphorbia bearing 6 species each and Phyllanthas bearing 5 species.On the other hand, Cyperus was the major genus in Liliopsida consisting of 5 species followed by Commelina consisting of 4 species.Species of all habit such as herbs, shrubs, trees, climbers (liana and vine) and grasses were found in this study area.Among the species, herbs represent 175 species and appear as a dominant habit which was 46.42% of total collection (Fig. 2) while shrubs, trees, climbers and others (Bamboo and grasses) representing 16.71%, 18.75%, 10.88% and 7.43% respectively.Regarding to habitat (place of collection), most species were found and collected from the road or railway side consisting of 138 species which were 36.60% of total habitat (Fig. 2).The second and the third largest habitat were fallow lands (25.46%) and homestead (24.40%) respectively.Many herbaceous weeds were found in crop field round the year with the seasonal cultivated crops especially in winter.Among the recorded plants, 30 species were cultivated as crops, 75 were planted and the rest were found as a wild species.Most of the trees and shrubs found in homesteads habitat were planted by the householders for their daily use such as fruit, vegetables, firewood, forage, construction materials, spices and herbal medicines or for economic benefits (Islam et al., 2015).Some species were found two or more habitat like fallow land and road side or homestead.Based on usefulness, a total of 229 species were found important for food, fiber, fire wood, medicine, spices, building materials, economic benefits and beautification.169 species are found significant for medicine.Local residents were accustomed to consume 67 species in from of fruit, vegetable and grain, 18 timber yielding species were used for furniture and others wooden work.The rest were important for miscellaneous uses such as oil, spices, fiber, forage, natural dye, building materials etc.In Bangladesh, plant immigration is a common scenario since long.Most of the plant introduced by settler, invaders or traders (Dutta et al., 2015).In this study, a total of 93 species were found as exotic species in the study area which was one fourth (24.67%) of the total collection.Among them, 49 were herbs, 16 were shrubs, 20 were trees and 8 were climbers.Regarding status of exotic species, 13 species were cultivated, 33 species were planted and 48 species were found wild.It is alarming that out of 48 exotic wild species, 35 species are spreading fast and are being a common species.Further research is needed to assess their impact on native species.Total 37 exotic species have medicinal potential for different ailments and 44 were useful to the householders., 2022).Rare species need to be specially cared and regularly monitored.

Identified threats to local plant diversity
On the basis of field observations and personal interviews as well as group discussions, the present study identified some threats on plant biodiversity of this area.In this regard, main threats are of two types.One is expansion of arable land and the other is the digging of ponds in low land for pisciculture.As a results of which fallow land as well as wet land is decreasing and demolish terrestrial, aquatic or sub-aquatic species.Another major threats were availability of the substitutes of natural product like plastic product, pharmaceutical product, synthetic dye etc.Other threats were lack of awareness among the residents about plants, use of unnecessary agrochemicals specially herbicides and pesticides, changes of cropping pattern, random collection of medicinal plants, filling the low lands, clearing the brushwood, unplanned construction activities and change of climates.
Based on this present assessment and information gatherd from informal discussion with the resident, some recommendation provided for judicious attention.First of all, infrequent and endangered plant should be considered for 'in-situ' and 'ex-situ' conservation.Secondly, local small nurseries or garden should be developed to grow the population of native rare species, wildlife-supporting species and medicinal plant species as well as infrequent species.Last but not least, awareness should be built up among the local people to save threatened and valuable plant species and their habitat.

Conclusion
This study indicates that Bagatipara Upazila is rich in Angiospermic species.Though some species are found to be exotic, fortunately most of the species are indigenous and important sources for medicine and food.Some threats have been identified and some locally rare species were found in this area.Therefore, some steps should be taken immediately, such as raising awareness among the residents about the importance of indigenous plant species; preserving plant diversity through various activities like construction, cultivation, and plantation; sustainable use and conservation of rare and medicinal plants, and protecting against habitat destruction.

Fig. 2 .
Fig. 2. Habit and habitat composition Conservation significance of local plant species Throughout the study on the basis of field observation of richness and their population size, eight species were found as rare or species of conservation concern for this area such as Artocarpus lacucha Buch.-Han.;Bridelia stipularis (L.) Blume; Callicarpa longifolia Lam.; Eranthemum pulchellum Andrews; Oroxylum indicum (L.) Kurz; Potentilla supina L.; Sterculia foetida L. and Terminalia arjuna (Roxb.ex DC.) Wight & Arn.Except Bridelia stipularis (L.) Blume and Sterculia foetida L. all species have medicinal potentiality.Potentilla supina L. is recollected after 118 years from this area(Hasan and Uddin, 2022).Rare species need to be specially cared and regularly monitored.