Arab GulfJournal ofScientific Research, 20 (2), pp 87-9/ (2002) ORIGINAL PAPER (REF. 2037) . -­ J A Abbas Coastal Vegetation of Bahrain Island Abstract: Vegetation of the coastal lowlands of Bahrain ~~I ~..r'~ .} ..,-bL....J1 ~4iJ1 .~I Island has been surveyed on the basis of seven habitat 1.>"4L~ types: mangrove, salt marsh, dunes, coastal sabkha, ,.; ~I 4b..WI,jbL:....JJ ~l+J1 .lh.i.ll 4.....1.J~ ~ .~I , ~~L.JI IF".J . w~1 Vo bL.J ~ ~ JJL;. Vo u->~I .J-'..? reclaimed areas, coastal plantations and agricultural ,'., 1 0 ; ,II ,jbL.:..J1 ,4b..WI t4-l1 ,4J....)1 u~1 ,~I w~1 wastelands. Most of the habitats are saline and plants are .........~ c:-JI I':'" ,.; ~ ..ci.J~1 ~I.J)I ,jbL.:..J1.J 4b..WI t),j.J1 mostly halophytic. Dominant species vary from one .~p'yJl tly)ll .J .~WI ~l+J1 tly)ll ~ Vo ~l+J1 w~1 ul-O J~~.J , ~ ~ wlj w~I.':'" ~ .:,I ..boo.J ..ci .J ' ~ habitat to another in the different saline areas. Habitats Vo o~WI ~l+J1 tly)ll ~L,u.J .~ o~WI ~l+J1 tly)Ol ~ with .Iow salinity are occupied by glycophytes. Key w~ ,~y..J1 ~ w~1 L..i .~I ,jbL.:..J1 .;. lS,Poi Jl ~ species in the vegetation of coastal lowlands of Bahrain ,jbL.:..J1 ,.; ~.)I ~l+J1 tly)Ol <':'.Jli.. ":,,c,.J ' ,~ ~ .~~ are found in similar habitats in Arabia, particularly the '~rJ I oJ-'-.:r.J I ~ .;. l+i)4i. C:" u->~I OJ-'..? .;. ~I 4b..W I ~~I ~ 4b..WI ,jbL.:..J1 .;. ~\...;".J ,ofo ~L.::...; ~.Ji W..boo.J eastern coasts of Saudi Arabia and Qatar. ..;hi U.J~ .J ~~~I ~rJl w...J~ Keywords: Bahrain, Coastal lowlands, vegetation, Habitat types Introduction Several studies have been carried out on the plant ecology and vegetation of Bahrain (Abbas et ai, Coastal habitats are highly stressful 1991 a & b; Abbas and EI-Oqlah, 1992; EI-Oqlah environments where salinity and the water-holding and Abbas, 1992; EI-Oqlah and Abbas, 1994; Abbas capacity of the substrate are the dominant abiotic and EI-Oqlah, 1996; Abbas, 1998). However, none of the previous studies have dealt exclusively with influences (Deil, 1998). These stressful conditions the coastal vegetation. Abbas and EI-Oqlah (1992) are aggravated in the Arabian Peninsula by high and EI-Oqlah and Abbas (1992) included mangrove temperature, reaching more than 45°C in summer. and the supralittoral vegetation as paJ1 of a more Many studies have been carried out on the coastal comprehensive survey of the vegetation of Bahrain. vegetation in Arabia. Coastal vegetation in Saudi The present study deals exclusively with the Arabia (Frey et al. 1984; EI-Demerdash et al. 1995), coastal vegetation of Bahrain Island, as reflected in Yemen (AI-Gifri and AI-Subai, 1994), Oman a number of habitats, and compares the Bahrain (Ghazanfar and Rappenhoner, 1994), United Arab coastal vegetation with the coastal vegetation of Emirates (Deil and MUller-Hohenstein, 1996), Qatar Arabia. (Abdel-Razik and Ismail, 1990; Abulfatih et al. 2001), and Kuwait (Halwagy and Halwagy, 1977) Study Area has been documented with some detail. Bahrain is an archipelago of 33 islands located in the mid-western part of the Arabian Gulf about 25 km east of Saudi Arabia. The largest of these J A. Abbas islands is Bahrain Island, with a total area of 612 Deanship ofScientific Research km2. Five physiographic zones characterize the University ofBahrain, topography of Bahrain (Doornkamp et al. 1980) P.O. Box 32038, Kingdom ofBahrain which are: (i) the central plateau and jabals; (ii) the Tel:(+974) 782357, 782307,683310 interior basin; (iii) the escarpments; (iv) the Fax: (+974)683278 backslopes; and (v) the coastal lowlands (Fig. 1). Email: [email protected] 87 88 Coastal Vegetation 50"20 The diagram Bahrain shows that the dry extends ~ay to 2S" October and the wet extends November to April. The mean annual rainfall is 74 mm, with a mean monthly rainfall in summer of than 1 mm and of 15 mm in winter. Relative humidity is generally high. The highest mean daily maximum relative humidity is (October), Skm and the mean daily I I minimum humidity is 40% (~ay). Methods Seven in the coastal lowlands of Bahrain Island were selected. The included mangrove, salt marshes, dune coastal soils), reclaimed areas, agricultural wastelands, and coastal '-­ _________________________---' plantations (Fig. 1). Each 1. ~ap of the physiographic zones and the was at least habitat types Physiographic zones: 1 == central plateau and once and the of a 2 == interior 3 == 4 backslopes; 5 coastal minimum of three stands per lowlands. Habitats: (d) == mangrove; salt marsh; dune; (0) == habitat was visually. coastal sabkha; (0) == == coastal plantations; (0) Species each habitat were wastelands. identified to - ~andaville and The coastal lowlands surround the central were kept in the Department of Biology core of Bahrain extending the base of the Herbarium at the of Bahrain. backslope, where the elevation is approximately 10 m, to sea The coastal lowlands consist largely Results of superficial laid of marine and Aeolian 1. This covers an area approximately swamps are located around the muddy 275 Km2 (Doornkamp et al. 1980). shores of the northeastern part the island {Tubli where a and two the bay. The of the zone and mainland Arabia, in the North the of the tidal channels are t1r.fnfr."rp·t1 by African-Euroasian dry climate province A vicennia marina Vierh. It contributes to (~cGinnies, 1979). According to climatic norms more 90% of the cover. Intertidal species obtained the Civil Aviation associated with plant are found in a zonation (Bahrain), the climate is characterized These include Arthrocnemum of mild winters and very hot summers. (~oric.) ~oris & is with a June Salicornia europaea L., Suaeda maritima maximum of January minimum and Arthrocnemum macrostachyum (~oric.) ~oris & (see, Table 1). Abbas J A 89 2. Salt Marsh are Limonium axillare O. Kuntze, At the northwestern the island, where Tamarix arabica DC. south sabkha, the cultivation ends near the coast, seawater intrusion, dominant species is H. pelfoliata. with with the borders of streams ditches through are A. macrostachyum, Halocnemum ridges, forms areas of salt marsh. Soils are strobilaceum (Pall.) M. Bieb., S. vermiculata, Z. characteristically sandy, and saline, often qatarense, and S. rosmarinus the southern with high water-table levels of the island (see, Table I). (Doornkamp et al., 1980). are mainly halophytic and found streams and ditches. 5. Areas Phragmites australis (Cav.) Steud and A number of coastal areas in the }uncus rigidus Desf. vegetation. island have been Other species include L., Alhagi urban and industrial projects. In such areas, maurorum Medikus, and littoralis the seawater were filled with sand and other (Gouan) ParI. (see, Table 1). dumping materials. Therefore, the soil is mainly unconsolidated sand. Dominant 3. in such new habitats are Sesuvium verrucosum Raf. Further inland and away northern and and Salsola villosa Del. ex Roem. northwestern coasts, and include Sporobolus spicatus (Vahl) the backs lope, dunes can Anabasis Moq., and Fagonia Burm. be seen. Relatively high dunes are found in the Table 1). northwest and southwest. The dunes are composed of quartoze sands, but in the gypsum 6. content of the sands may be et at., 1<W''''U1V'''' are concentrated along the 1980). In the large dunes the main and northwestern areas. Date including Leptadenia "'""'''Of'I''''' is the main planted tree in Calligonum comosum ornamental trees and Hadidi, and have been grown in gardens and parks and Panicum turgidum Forssk., and divisum roads. these are introduced Henr. Two types of smaller dunes are including camaldulensis obtusa ~~'''''''''' in the western and northern Some Ficus retusa (Th.) Mig., Prosopis are in inland areas with (Sw.) and Nerium oleander L. A number are mainly in the form of native and weeds grow in these Z. qatarense. In addition to Z. qatarense, habitats. The were found in or at conglomeratus Rottb., P. divisum, P. date palm plantations: LUlJl),'.U!. Helianthemwn kahiricum and spinosa L., australis, A. maurOTUm, coccineum L. are Euphorbia peplus Prosopis farcta (Banks & in the western and southern saline Sol.) Macbride, Centaurium pulchellum (Sw.) In these areas, ''''''• .lU rosmarinus Druce, Convolvulus arvensis L., and Sporobolus ioclados ex Trin.) Dactyloctenium (L.) WiUd. (see, Table lagopoides (L.) and Suaeda 1). vermiculata Forssk. ex J.F. Gmelin dominate the Table 1). 7. Agricultural Many areas show the remnants of dead P. 4. Coastal Sabkha dactylifera. These areas are mainly saline and thus The coastal sabkhas are in the occupied in by dense thickets of S. and in the south. Extensive vermiculata. species frequently sabkha are to seen in such include Cressa cretica L., H. inundation. The soil is composed of strobilaceum, P. In laminated, poorly graded, medium- wasteland with low other species were calcareous quartose sand. A. found, including Aizoon canariense Heliotropium qatarense, Halopep/is crispum Desf., and P. farcta Table 1). ex Aschers., and S. sabkha. Scattered these 90 Coastal Vegetaion of Bahrain Table 1. The seven habitats and their related species. Habitat Species composition Mangrove A vicennia marina, Arthrocnemum salicornicum, Salicornia europaea, Suaeda maritima, Arthrocnemum macrostachyum Salt Marsh Phragmites australis, ]uncus rigidus, Cyperus rotundus, Alhagi maurorum, Aeluropus littoralis Dunes Leptadenia pyrotechnica, Calligonum comosum, Zygophyllwn qatarense, Panicum turgidum, Pennisetum divisum, Cyperus conglomeratus, Helianthemum kahiricum, Cynomorium coccineum, Seidlitzia rosmarinus, ]uncus rigidus, Sporobolus ioclados, Aeluropus lagopoides, Suaeda