Гіллястовусі раки Львівщини (Crustacea: Cladocera) у гідробіологічних дослідженнях Б. Дибовського та М. Гроховського (за матеріалами круглого столу екологічної комісії наукового товариства ім. Шевченка)

Abstract

49 taxa of Cladocera were registered in the reservoirs of Lviv region according to the materials of B. Dybovskyi and M. Grohovskyi. From the point of view of faunal diversity, the studied locations can be divided into two groups. The first group of locations (registered 10 or more taxa each): Pelchynsky pond, Yanivsky pond, Big Golosko. The second group of locations (up to 5 taxa are registered): Kilinsky Park, Sobka pond, Small Golosko, Zboishcha, Snopkiv, Horodok, Zhydachiv. The largest number of Cladocera taxa was registered in the Janivsky pond (21 taxa). The smallest number (1 taxon) was registered in the location Zboyishcha. Taking into account the frequency of occurrence, 4 groups of taxa were distinguished. The first group has a frequency of 10 % (34 taxa), the second – 21 % (10 taxa), the third – 30 % (4 taxa), the fourth – 50 % (1 taxa). The most common taxa with a frequency of 30 % include Alona affinis, Leydig., Ceriodaphnia polonica, nob., Peracantha truncata, O. Fr. Müll., Sida crystallina, O. Fr. Müll. The frequency of occurrence of 50 % is characteristic of Simocephalus vetulus, O. F. Müll. The measure of pairwise similarity of the Cladocera fauna of reservoirs of various locations, calculated by the Jaccard index and the Sørensen index, has the same trends. 23 pairs of water bodies do not have common species. For them, the Jaccard index and the Sørensen index are equal to zero. The highest coefficient of similarity of fauna between the reservoirs of the locations Kilinsky Park and Zboiyshche (Jaccard’s index – 33 %, Sørensen’s index – 50 %). The lowest rate was registered for the locations Yaniv – Zhidachiv and Small Golosko – Yaniv (Jaccard’s index – 4 %, Sørensen’s index – 8 %). The Jaccard index is characterized by a larger amplitude of the calculated indicators and gives better differentiation at high and average indicators of similarity. With low indicators of similarity, the Sørensen index is preferred. The conducted research is of particular interest in view of the faunal analysis of Cladocera groups and the comparative characteristics of indicators identifying long periods of time. Such materials are one of the key aspects on which the issue of hydroecological monitoring is based.