The composition and seasonal variation of the algal turf of Lake Ladik were studied using samples
collected from one station between June 2000 and May 2001. 50 taxa of diatoms were identified
in the epiphyton. Navicula veneta, N. halophila, Nitzschia fonticola and Aulacoseira distans were
particularly important on turf community. During the October month several Navicula species
become progressively more important. Gomphonema lateripunctatum was particularly notable.
Other diatoms were occasionally abundant, including Cymbella affinis, C. silesiaca, Navicula
cryptocephala, Gomphonema olivaceum and Cyclotella ocellata. Also Navicula lanceolata and
Anomoeoneis brachysira were conspicuous, owing to their large size, but were never numerically
abundant. Fragilaria ulna and Nitzschia palea were found in low numbers in study area and this
pointed out there has not been a remarkable abundance of algal pollution in Lake Ladik. The
associations between July and August with bonds to June, January and February with bonds to April
were most significant in the study period obtained by cluster analysis. Shannon diversity and
evenness presented small variations during the study period. Lake Ladik presented low values of
species richness particularly during summer period and highest values were recorded in April.
According to canonical correspondence analysis, there was association between some Navicula
and Nitzschia species with PO4
, NH3
N. Also the multivariate analysis showed, temperature as the
most important factor in the distribution and abundance of diatoms on turf biomass