Güllük Lagoon (Aegean Sea, Turkey) Ecosystems

Authors : Özdemir EGEMEN, Mesut ÖNEN, Baha BÜYÜKIŞIK, Belgin HOŞSUCU, Uğur SUNLU

Pages : 927-948

View : 20 | Download : 10

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Güllük Lagoon has an area of 2500 decares with a depth of 0.5-5.0 m and is connected to Güllük Bay by a channel. In this study, samplings of phytoplankton and benthos were taken physico-chemical parameters were recorded monthly during 1993 at 5 stations. The temperature reached a minimum of 10.42°C in January and a maximum of 26.9°C in July, with a mean annual temperature of 19.53±1.511. The salinity in the lagoon ranged from 7.48 ‰ to 13.92 ‰ in January and March, respectively with a mean annual silinity of 10.65 ± 0.555. Dissolved oxygen in the sub-surface insert ignore into journalissuearticles values(0.25 m); water was 5.56 mg 1-1 in June and 9.06 mg l-1 in February, with an annual mean 7.31 ± 0.331. The Secchi-disk depth was 1.12 m in May and 2.40 m in October. Nutrient measurements revealed moderately high levels of ammonia insert ignore into journalissuearticles values(ranging from 4.39 to 29.70 µg-at l-1);, low nitrate insert ignore into journalissuearticles values(0.81 to 17.87 µg-at l-1);, nitrite insert ignore into journalissuearticles values(0.19 to 1.35 µg-at l-1);, phosphate insert ignore into journalissuearticles values(0.01 to 0.45 µg-at l-1);, and silicon insert ignore into journalissuearticles values(0.26 to 6.00 µg-at l-1);. Chlorophyll a distribution generally indicated that productivity was highest in May insert ignore into journalissuearticles values(21.49 mg l-1); and lowest in September insert ignore into journalissuearticles values(0,77 mg l-1);. Melosira moniliformis was the predominant phytoplankton species. All of the stations were characterized by high species diversity. Identification of the benthic species was carried out with 60 samples collected from 5 stations in a of one year period. As result 68 benthi species belonging to 7 taxa insert ignore into journalissuearticles values(Nemertina, Polychaeta, Oligochaeta, Crustacea, Mollusca, Insecta, Echinodermata); were identified. The polychaetae were numerically dominated by Notomastus latericeus insert ignore into journalissuearticles values(3737 individuals);, followed by Hediste diversicolor insert ignore into journalissuearticles values(1524 individuals);, and Spionidae insert ignore into journalissuearticles values(sp); insert ignore into journalissuearticles values(1361 individuals);. Economically important fish species in Güllük Lagoon consist of mullets insert ignore into journalissuearticles values(Mugil cephalus, M. capito, Chelon labrosus, Liza saliens);, Sparus aurata insert ignore into journalissuearticles values(gilthead sea bream);, Dicentrarchus labrax insert ignore into journalissuearticles values(sea bass);, Solea solea insert ignore into journalissuearticles values(sole);, Anguilla anguilla insert ignore into journalissuearticles values(eel); and Cyprinus carpio insert ignore into journalissuearticles values(carp);, with an annuall yield varying from 10 to 69 tonnes.
Keywords : Güllük lagoon, physico chemical parameters, planktonic and benthic organisms, fish productivity