G. Fekete szerk.: Studia Botanica Hungarica 9. 1974 (Budapest, 1974)

Vida, László: Diatoms from a brooklet affluent to Arax river (Armenian Republic, USSR)

The characteristic frequency and frequency-distribution of the specimens belonging to different salinity groups might be analyzed in a similar way. Marking the frequency number used during the analysis from 1 to 5 with "f

'; the number of taxa belonging to a certain salinity group with "t"; the frequency number characterizing the certain group can be given by the following formula: n = 10"f~lt

. Calculated according to the above formula, the characteristic values of the sample material are as follows: indifferent . io

4 + 3 2x10 + 2xl0

2 + 8x10 + 24 = 12304 ( 33,3 % halophylous 4 = 2x10 + 2xl0

3 + 3xl0

2 + 5x10 + 10 = 22360 ( 60, 5 % mesohalobe = 2x10 + 3xl0

2 + 3x10 + 3 = 2333 ( 6,2 % 36997 (100,0 %) There is no doubt that the method expounded above cannot replace the exact means of quantitative analysis. However, the author believes that it gives fundamentally better information about the distribution patterns of a certain material than the distribution patterns of a certain material than the plain account of the number of taxa partaking in a given group. The method also might prove to be profitable when one either needs merely quick, informative data or when there is no way to follow exact methods - as in the case of the present sample

. The results of detailed identification are given below. The enumeration follows the taxonomic system of HUSTEDT (1930-1966), the sequence within a genus is alphabetic. The frequency rate is given by the number after the taxon name, signifying as follows: 5 = abundant, 4 - frequent, 3 = average, 2 = sparse, 1 = rare occurence within the material of the sample

. The letter symbol following the frequency number gives the group of salinity, according to data in literature, using KOLBE' s (1927) classification: I - indifferent, H = halophylous, M = mesohalobe taxon. The question mark following the name of a taxon refers to the remarks after the enumeration. ENUMERATION 1. Thalassiosira fluviatilis HUST. 5H 2. Cyclotella meneghiniana KÜTZ. 1H 3. Stephanodiscus astaea var. minutula (KÜTZ.) GRUN. 2H 4. Stephanodiscus hantzschii GRUN. 2H 5. Coscinodiscus lacustris GRUN. 1H 6. Diatoma vulgare BORY 21 7. Diatoma vulgare var. ovális (FRICKE) HUST. ? 31 8. Fragilaria capucina var. lanceolata GRUN. ? 21