Fosfat Ve Silikatin Zararli Denizel Diyatom Büyümesi Üzerine Etkisi: Thalassiosira Allenii Takano (Bacillariophyceae)

Ozet:Thalassiosira allenii(Takano) turunun fosfor ve silikattan nasil etkilendigini daha iyi anlamak icinbuyume hizlari uzerinde 6 farkli reaktif PO4 ve 6 farkli reaktif Sikonsatrasyonunun etkileri arastirilmistir. T.allenii turu, IzmirKorfezi-Kuzey Ege-Turkiye’den izole edilerek, f/2 zenginlestirme ortaminda,surekli-aydinlik periyotta ve kesikli kultur sisteminde inkube edildi. Turunbuyumesi eksponensiyel buyume fazi takip edilerek Chl a (µgl-1)olarak olculdu, elde edilen verilerin istatistiksel analizi en kucuk karelermetoduyla yapildi. Her bir nutrient icin hesaplanan Ks ve µmax degerlerisirasiyla: PO4 icin Ks= 0.544 µM-PO4-P ve µmax=0,972 gun-1, Si icin -Ks=0,615 µM Si ve µmax=0,989gun-1 olarak bulundu. T.alleniituru, PO4-P sinirli gelisim gosterirken, silikat sinirlayiciligitespit edilememistir. Bu sonuclar, ozellikle evsel kirletici yukun yogun olduguve Si degisimlerininin sik yasandigi kiyisal sularda T.allenii turunun asiri alg cogalmalarinda yeralma yetenegine sahipoldugunu gostermektedir.Anahtarsozcukler: Denizel diyatom, buyume hizi, fosfat, silikat,yari-doygunluk katsayisiAbstract:In order to betterunderstand the effect of phosphorus and silica on Thalassiosira allenii(Takano), the effects of 6 differentconcentrations of reactive PO4 and 7 different concentrations of reactive Si were investigated. T.allenii wasisolated from Izmir Bay-NorthernAegean Sea-Turkey and incubated in a f/2 enrichment medium under constant lightin a batch culture system. The growth rate of the species was measured as Chl a(mg/l) by monitoring theexponential growth phase. The statistical analysis of the obtained data wasperformed by utilizing the method of least squares. Half saturationconstant (Ks) and maximum spesific growth rate (µmax)values estimated for phosphorus and silicawere obtained as follows: Ks=0,55 µM PO4-P and µmax=0,847day-1 for phosphorus, -Ks=0,615 µMSi and µmax=0,989 day-1 for silica.This results shows that T.alleniispecies has ability to take a great role on algal blooms in coastal waterswhich particularly domestic pollution load intense and changes of Si frequentlyexperiencing.Keywords: Marine diatom, growth rate, phosphate, silicate,half saturation constant