TARIM BILIMLERI DERGISI 2001, 7 (3), 74-80 Ecological, Anatomical and Morphological Studies on Ulva rigida C. Agardh (Ulvaceae, Chlorophyta) in the Coast of İzmir (Aegean Sea-Turkey) Berrin DURAL° Nilsun DEM İ R2 Geliş Tarihi : 27.02.2001 Abstract: A series of morphological, anatomical and ecological characters of Ulva rigida collected from six locations along the coast of Izmir were determined. The size and morphology of thallus, thickness of marginal, mid and basal regions showed variations according to the changes in season and location. U. rigida consisted of smaller thalli in nutrient limited rough water coast and produced larger, lobed thalli which was characteristic of spring summer growth in relatively stagnant coast rich in nutrients. Thallus length and thallus breadth varied between 2-360 cm and 3-160 cm, respectively. The increased concentrations of nutrients due to the pollution were effective on anatomic and morphometric characters. Key Words : Ulva rigida, green alga, eutrophication, morphology, anatomy İzmir Kıyı lannda (Ege Denizi-Türkiye) Ulva rigida C. Agardh (Ulvaceae, Chlorophyta) Üzerine Ekolojik, Anatomik ve Morfolojik Çal ışmalar Özet : Izmir kıyısı nda 6 bölgeden toplanan U. rigida örneklerinde bir seri morfolojik, anatomik ve ekolojik özellikler belirlenmiştir. Tallusun boyutu ve morfolojisi, marjinal, orta ve bazal bölgelerin kal ı nlı kları , mevsim ve bölgesel değişimlere göre varyasyonlar göstermi ştir. U. rigida, besince s ı n ırlı dalgal ı kıyı larda daha küçük tallusa sahipken, besince zengin nisbeten durgun k ıyılarda ise yaz bahar gelişiminin özelli ği olan daha büyük ve loblu tallusa sahiptir. Tallus uzunlu ğu ve genişliği sırasıyla 2-360 cm ile 3-160 cm aras ı nda değişmiştir. Kirlenme nedeniyle artan besin maddeleri derişimi anatomik ve morfometrik özellikleri etkilemektedir. Anahtar Kelimeler : Ulva rigida, yeşil alg, ötrofıkasyon, morfoloji, anatomi Introduction Recently, the Aegean Sea has been exposed to Ulvales species were grouped into pollution tolerated coastal eutrophication (Dural et al., 1989). Especially, algae (Boudouresque 1984) and there is a large scale İzmir bay has been heavily polluted by municipal and distribution in Izmir bay and the outside of the bay. Eight industrial wastes. Ulva rigida C. Ag. forms excessive species of Ulva were recognised in the coast of Turkey populations in areas which has a low diversity due to the and U. rigida was the most common component. This eutrophication. U. rigida has been found widespread along species was frequently found in the inner bay after the shores of the Mediterranean (Malea and Haritonidis, Narl dere. But it was found only in small ports and U. rigida Ieading to anoxia in ı 2000). Extensive blooms of fishermen shelters surrounding point pollution sources in large parts of the Venice lagoon are rapidly reducing the the Karaburun, Çe me and Seferihisar coasts (Güner and quality of the ecosystem and affecting its use as a natural ş Aysel 1978, Zeybek et al. 1983, Güner et al. 1983/84, source for fishing, aquaculture and recreation (Runca et Güner et al. 1985, Dural et al. 1989, Cirik et al. 1990, al., 1996). U. rigida blooms resulting from pollution were Dural 1990, Aysel et al. 1991, Güner et al. 1992, Aysel also reported at the north-western Mediterranean and Erdu ğ an 1995, Aysel and Şipal 1996, Everest et al. (Rodriguez-Prieto and Polo 1996). It was reported that the 1997, Aysel et al. 1998 ). chlorophyte Ulva lactuca was the most abundant organism in the intermediately polluted areas at Quequen, Argentina Earlier studies based on the morphology, biology and (Lopez-Gappa et al. 1990). The Brittany coast line where culture of Ulva genus were done by Dangeard the slope of shore is gentle and the sand is fine, is (1960,1963). Then, Bliding (1968) by undertaking a major consistently affected by annual Ulva sp. blooms (Piriou revision of the genus, used a comprehensive list of 1996). The similar shore structure together with high anatomical and morphological characters to describe the nitrogen flows especially in spring may enhance eight species of Ulva from Europe. Later studies have eutrophication in the coast of İzmir. been based on Bliding's work (Vinogradova 1974, Longo and Giaccone 1974, Hoeksema and Van Den Hoek 1983, Koeman 1985). Aegean Univ. Fac. of Science, Department of Botany-Izmir 2 Ankara Üniv. Agricultural Faculty, Department of Fisheries-Ankara DURAL, B. ve N. DEM İ R, "Ecological, anatomical and morphological studies on Ulva rigida C. Agardh (Ulvaceae, Chlorophyta) in the coast of Izmir (Aegean sea - Turkey)" 75 Bliding (1968) considered that pyrenoid number, multiple range test were computed to evaluate the thallus thickness, and size and arrangement of cells were differences in terms of the parameters. non-variable characters. Subsequent studies focused on the variability of vegetative characters and have Result and Discussion demonstrated that, in some Ulva species, thallus thickness, cell size and pyrenoid number are too variable In Izmir coast, the morphology of U. rigida varied with for taxonomic use (Vinogradova 1974, Saifullah and the changes in location, season and developmental Nizamuddin 1977). The changes in nutrient concentrations stages. U. rigida consisted of smaller thalli in nutrient resulted from poliution may affect the morphological and limited rough water coast and produced larger, lobed thalli anatomical characters in Ulva species. As a result, culture characteristics of spring summer growth in relatively is necessary for taxonomical studies. But the cell shape in stagnant coast rich in nutrients. Similar patterns of transverse section of the basal region were reported as morphology has been reported for the European and non-variable characters in the southern Australian Ulva southern Australian populations of U. rigida (Dangeard species (Phillips 1988). 1959, 1963, Phillips 1988). 90 % of total thallus from Narl ı dere, 87.5 % from Bal ı kl ı ova and 72.5 % from This study involves a combination of extensive fı eld Çeşme, were found as orbicular, simple or lobed and and anatomical studies. U. rigida from different localities sligthly holed. 65 % from Urla, 60 % from Karaburun and in the Izmir coast has been sampled in an attempt to 55 % from Seferihisar were lanceolat, margines towards evaluate the variation in morphological and anatomical the center were deeply lobed and fenestrated. These characters due to the pollution. showed the effects of hydrodynamism on lanceolate structured individuals. The colour of plant was darker green in sheltered localities. Material and Methods U. rigida populations showed a considerable Izmir bay locates between 38 ° 10' N , 38° 40' N and variation in the size of thallus, cells and the thickness of 26° 15' E, 27° 10' E coordinates (Fig. 1). The bay is thallus (Table 1). The variations in the thickness of heavily polluted from industrial and domestic sources marginal, mid, and basal regions; cell height in transverse which decreases in the outer bay gradually. The deepest section and cell size in surface section were found to be point is 15 m in the inner bay to the Narl ıdere coast and statistically significant by seasons and locations (p<0.05) there is no algae except some Cyanophyceae species. (Table 2). Thickness of thallus was increased from The middle bay (max. depth 45 m) locates between Narl ı dere and Urla. Because the coast between Narl ı dere and Urla shows high diversity, it is evaluated as moderately polluted area and the characteristic pollution tolerated algae are abundant. Urla, Bal ı klı ova and Karaburun are situated in the outer bay. The pollution decreases from Urla to Karaburun gradually. Çe şme and Seferihisar are the least affected coast from pollution since they are located in the outside of the bay. The samples were taken in January, April, August and November 1998. The samples of U. rigida were collected from the areas surrounding the point pollution sources in the six locations (Narl ı dere, Urla, Bal ı kl ı ova, Karaburun, Çeşme, Seferihisar) on gently sloping rocks and shells. The concentrations of nitrite, nitrate, ammonia- nitrogen and orthophosphate were analysed in the water samples taken from the sampling locations according to Strickland and Parsons (1972). Temperature and pH were measured in situ. Attached individuals from the centre of distribution of the populations were collected. The following measurements were recorded: thallus length and breadth, and the thickness of the marginal, mid and basal regions of the thallus. The basal region of the thallus is defined as the non-rhizoid-containing region immediately adjacent to where there are rhizoids between the two cell layers. A subsample of 10 plants was selected and the following was recorded for each of 10 cells from the marginal, mid and basal region of the thallus : cell length and breadth (in surface view) ançl cell height (in trasverse section) (Phillips 1988). Statistical analysis were performed by using Minitab and Mstat programmes for Fig. 1. The study area and locations of sampling : 1.Narl ıdere, me, 6.Seferihisar Windows. Variance analysis (ANOVA) and Duncan 2.Urla, 3.Bal ı kkova, 4.Karaburun, 5.Çe ş 76 TARIM BILIMLERI DERG İSİ 2001, Cilt 7, Say 3 Tablo 1. The mean (±Standard deviation), maximum and was 11.5 pm in spring and summer in Narl ı dere, Urla, minimum values of morphometric parameters of U. Karaburun and Seferihisar. rigida in 1998 (N=240)* Parameter Mean±SD Max. Min. Cell length in marginal surface section (MSCL): TL (cm) 26.4±2.58 360 2 The highest mean value of cell length in marginal surface TB (cm) 16.6±1.47 160 3 section was 20 pm in summer in Çe şme. The maximum MT (pm) 52.4±0.50 75.9 34.5 value was measured as 23 pm in summer and in autumn MTCH (pm) 18.8±0.22 27.6 11.5 in Çeşme and Urla. MSCL (pnn) 14.8±0.20 23 8 MSCB (pm) 12.4±0.17 20.7 5.3 The lowest mean value was 12.2 Nm in spring and autumn MiT (pm) 89.1±1.16 185 57.5 in Bal ı kl ı ova and Karaburun and the minimum vaiue was 8 MiTCH (pm) 28.9±0.49 52.9 13.8 pm in spring in Seferihisar.