Journal of Aquaculture & Marine Biology Research Article Open Access Study on morphological characters of some mangrove plants in South-eastern Ayeyarwady Delta of Myanmar Abstract Volume 8 Issue 4 - 2019 A study on the mangrvoe plants in Pyapon Township, Ayeyarwady Region, South- Kyi Kyi Myint, Myat Myat Nwe, Tin Lay Mar eastern Ayeyarwady Delta (between Lat. 94˚30′ and 95˚45′ North and between Long. 15˚30′ and 16˚25′ East), Myanmar was conducted within the period of March 2016 to Department of Botany, Magway University, Myanmar February 2017. A total of 18 species of mangroves plants were recorded in the natural Correspondence: Kyi Kyi Myint, Associate Professor, mangrove areas. In the present study, the taxonomic descriptions of mangrove plants Department of Botany, Magway University, Myanmar, were presented. Email Keywords: taxonomic, Ayeyarwady Delta Received: July 06, 2019 | Published: July 25, 2019 Introduction the mangrove forest in Bangladesh, is the largest mangrove forest in the world. Australia has the third largest area of mangroves in the ‘Mangrove’ has been variously defined in literature. The oxford world. India is one of the 15 most mangrove-rich countries having 2.7 dictionary mentioned the words ‘mangrove’ and ‘mangrowe’ since % of global total area of mangroves. Asia contains most of the world’s 1613, indicating tropical trees or shrubs found in coastal swamps with mangroves with 46%.12 The largest areas of mangrove in Southeast tangled roots that grow above the ground, whereas the Americans, the Asia are found in Indonesia (almost 60 % Southeast Asia’s total), Spanish, and the Portuguese used the term ‘Mangle’ and ‘Mangue’ Malaysia (11.7%), Myanmar (8.8%), Papua New Guinea (8.7%) and 1 indicating trees and shrubs of the genus Rhizophora. Later, the Thailand (5.0%). term ‘mangrove’ was referred to the individual plant or tidal forest or both, as ‘Mangrove plants’ and ‘Mangrove ecosystem’.2 In Globally, there are 110 recognized species of plants classified as addition, mangroves have been defined by Hamilton and Snedaker3 mangroves, belonging to 20 different families.13 However, Tomlinson4 as salt tolerant ecosystems of the intertidal regions along coastlines. reported that around 34 major and 20 minor mangrove species Moreover, the term ‘mangrove’ is used to define both the plants that belonging to about 20 genera in over 11 families have been recorded occur in tidal forests, and to describe the community itself.4,5 Mangrove globally. plants mostly grow within the sheltered intertidal flat deltaic lands, It is well known that Southeast Asia’s mangroves are the best funnel-shaped bays, broad estuarine mouths, shallow or frequently developed and probably the most species-diverse in the world. Giesen 6 tidal inundated coast lines. & Wulffraat, 1998 reported that 52 species are found in the Southeast Mangrove forests were of crucial significance for local people, Asian. Wang et al.14 reported that 59 species in 41 genera and 29 providing food, shelter and, medicinal and other uses. The local people families of mangrove plants were recorded in India and 26 species depend on mangroves for fire-wood, charcoal, timber, poles and many of 12 families and 15 genera were from China. Hening15 recorded other purposes. Traditional uses of mangrove resources currently 69 species under 34 families in the whole of Sundarban mangrove. continue side by side with large-scale and intensive exploitation using However, Karim16 reported 123 plant species belonging to 22 families high-capital investment and technologies such as charcoal production representing 30 genera in Bangladesh. Santisuk17 reported that 74 and firewood. In recent years, efforts to convert mangrove land for species under 53 genera were recorded in Thailand. other uses, such as fish- or shrimp-ponds or industrial and human Myanmar is endowed with a rich diversity of habitat types arising settlements have been increasing in number and size. Nevertheless, largely from its unusual ecological diversity. Myanmar has more than mangrove provided directly and indirectly uses in various ways. 2,000kilometres of coastline along the Bay of Bengal. Generally, it The mangrove forests provide livelihood and employment to wood comprises the Rakhine, Ayeyarwady Delta and Tanintharyi region, cutters, fishermen, honey and wax collector, shell collectors, timber where mangroves are common. About 8.8percent of Southeast Asia’s traders and their workers and other peoples who work both seasonally mangroves are located in Myanmar, of which 46 percent is located in and round the year in the forest. Ayeyarwady (Irrawaddy) Division, 37 percent in Tanintharyi Division and 17 percent in Rakhine State. The largest mangrove areas were Mangroves occur in 112 countries and global coverage has been observed in Ayeyarwady Delta having 180,826 ha compared to other 2 7 8 estimated at over 179,000km , 10million hectares, 14-15million areas of Rakhine (64,777ha) and Tanintharyi (140,485ha). Mangrove 9 10 4 hectares and 24million hectares, more than 18million ha. A study by forests are mainly found in Bogalay, Pyapon and Laputta townships, 11 Giri et al. estimated that the total mangrove forest area of the world which are situated in the south of the Ayeyarwady Delta.18 The total 2 in 2000 was 137,760km with the largest extent of mangroves found area was about 530,000 hectares in 1980, but it decreased to 425,000 in Asia (42%) followed by Africa (20%), North and Central America hectares by 2000, or perhaps as low as 382,032ha. (15%), Oceania (12%) and South America (11%). The Sundarbans, Submit Manuscript | http://medcraveonline.com J Aquac Mar Biol. 2019;8(4):118‒128. 118 © 2019 Myint et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Copyright: Study on morphological characters of some mangrove plants in South-eastern Ayeyarwady Delta of 119 Myanmar ©2019 Myint et al. The various authors studied the marphological characters of and 95˚45′ North and between longitudes 15˚30′ and 16˚25′ East), mangrove plants along the various localities of Myanmar coastal Myanmar. regions byThan Htay and Saw Han,19 Aung Myint & Kyaw Soe,20 Observation of Mangrove plants in the field: In this study, mangrove Cherry Aung,21 San Tha Tun,22 Tin Hla and Htun Paw Oo,23 Thi Thi plants were collected from March 2016 to February 2017. The Htaik,24 Mar Lar,25 San Tha Tun,26 Nyo Nyo San.27 The purpose of morphology of mangroves were recorded from the natural mangrove this study is to elucidate the distribution, occurrence and taxonomic areas. Taxonomic descriptions were described in the fieldwork and descriptions of mangroves. floral parts such as flowers, leaves were taken to the laboratory to Materials and methods make herbarium sheets and preserved.To study the morphology of the mangroves, twenty transects were assigned perpendicular to the creek Study area: The natural mangrove formations were observed along crossing through the forest from seaward to landward. Permanent the Tebinzeik creek and Thaung-ga-done creek that located between plots (10m×10m) were set along each transect. T1–T7 were set from Htaung Gyi Tan and Ah Shey Hpyar villages and War Kone village. near the Htaung Gyi Tan village, T8–T16 from Ah Shey Hpyar and T17– War Kone village is situated at the inner part of Ahmar Sub-Township. T20 from War Gone villages respectively. The location of the transect These villages were located the south-eastern Ayeyarwady Delta, lines along the creek of mangrove areas were shown in the Figure 1. Ayeyarwady Region, Pyapon Township (between latitudes 94˚30′ Figure 1 Map showing the study areas within the South-eastern Ayeyarwady Delta, Pyapon Township, Ayeyarwady Region, Myanmar Results Inflorescence raceme, spike 11.0-16.0cm long, peduncled. Flowers 5.5-6.0cm long and 3.3-3.5cm across; bract 1, 1.5-1.8cm long and 0.8- In the present study18 species of mangroves that belong to 11 1.0cm broad, curved, ovoid, entire, acute, basal cup-shaped, glabrous, families and 13 genera have been recorded from the natural mangrove greenish yellow; 2 bracteoles partly covered by bract, smaller than areas of Htaung Gyi Tan, Ah Shey Hpyar and War Gone villages, bract; showy flower, erect, sessile, bisexual, zygomorphic, complete, Pyapon Township, South-eastern Ayeyarwady Delta. The recorded hypogynous. Sepals 4, aposepalous, 2 outer one larger, 2 inner one plants included 14 species of woody trees, 2 species of shrubs, 1 smaller, ovate, 1.7-2.0cm long and 0.8-1.1cm broad, acute, basal species of monocot plams and 1 species of fern. curved, coriaceous, glabrous, greenish, persistent. Petals 1, ovate, 3.5- The classified list of mangrvoe plants were mentioned in Table 1 4.0cm long and 2.5-3.0cm broad, entire, obtuse, coriaceous, slightly and the morphological descriptions were also presented. fleshy, slightly curved, margin outer folded, large, showy, white, deciduous. Stamens 4, free, filament about 1.9cm long and about Acanthus volubilis Vahl. 0.25cm broad, fleshy, solid, white, glabrous, flattened, erect; anther Syn: Dilivaria ebracteata Vers. dithecous, about 0.8cm long, basifixed, densely white, pubescent, longitudinal dehiscence, inserted, introse. Carpels 2, syncarpous, Shrubs, upto 1.5m height. Stem solid, glabrous, terete. Leaves ovary dumble shaped, 0.2-0.3cm long, glabrous, terete, two locules, simple, opposite and decussate, exstipulate; petiole 0.5-0.7cm long two ovules in each locule, ovary superior, axile placentation, style and 0.3-0.4cm broad, solid, glabrous, pulvinous; lamina oblong to terminal, persistent, glabrous, white, stigma bifid. Fruit capsule, 2.5- elliptic-oblong, 10.0-12.0cm long and 4.0-5.0cm broad, the base 3.0cm long and 0.8-1.0cm in diameter, glabrous.