Сезонна динаміка щільності поселення круговійчастих інфузорій (Ciliophora, Peritrichia) ріки Уж

Abstract

Вивчено видовий склад круговійчастих інфузорій ріки Уж (м. Коростень). Ідентифіковано 18 видів перитрих, які належать до 8 родів. Досліджена динаміка щільності поселення перитрих та її залежність від фізико-хімічних параметрів води (температури, вмісту розчиненого кисню, рН). Встановлена пряма залежність щільності поселення цих інфузорій від температури (r=0,74, р=0,005) та вмісту розчиненого кисню (r = 0,51, р=0,001).

Изучен видовой состав кругоресничных инфузорий р. Уж (г. Коростень). Идентифицировано18 видов перитрих, которые относятся к 8 родам. Исследована динамика плотности поселения перитрих и ее зависимость от физико-химических параметров (температуры, содержания кислорода, рН). Установлена прямая зависимость плотности поселения кругоресничных инфузорий от температуры (r = 0,74, р=0,005) и содержания растворенного кислорода (r = 0,51, р=0,001) .

Peritrichous ciliates (Peritrichia Stein, 1859) are the important component of the freshwater reservoirs bioceonosis. They take part in sustaining biological balance in the reservoirs and in water self-purification processes. Peritrichia are rather sensitive to any changes in their environment and, thus, they are indicators of water reservoir sanitary hygienic state. The aim of the research – is to study seasonal changes in the peritrichia population density in the river Uzh and to find out its dependence on hydrophysical and hydrochemical water parametrs. The peritrichous ciliates species composition in the river Uzh (the town Korostenʹ) is researched. 18 peritrichia species from 8 families are identified. The research of peritrichia population density dependence on physical-chemical water parametrs (the temperature, the dissolved oxygen content and the active reaction) is done. Peritrichia were found from +0,5оС to +22оС water temperature. In the research period peritrichous ciliates population density varied from 1,31 to 7,71 sp/сm2. Two peaks in peritrichia population density (5,04-6,78 sp/сm2 and 6,56-7,71 sp/сm2) were registered at the beginning of the summer and the autumn. Maximum peritrichous ciliates population density coincided with higher water temperature (14-22оС). At lower temperature (0,5-11 оС) lower peritrichous ciliates population density (1,31-2,96sp/см2) was observed. In the research period the dissolved oxygen content in the river Uzh varied within 4,4-10,3 mg/dm3. Beginning from March and up to the beginning of July this index increased from 6,7 to 10,3 mg/dm3. In July the decrease to 4,8 mg/dm3 was registered. In our opinion these changes in dissolved oxygen concentration resulted in peritrichous ciliates population density decrease in this period. At the end of the summer the increase of oxygen content to 7,9 mg/dm3 was registered. During the autumn gradual decrease of this index from 9,9 to 5,4 mg/dm3 and in December to 4,4 mg/dm3 was observed. Thus, the increase of dissolved oxygen content (8,4-10,3 mg/dm3) and higher temperatures(14-22 оС) make favorable conditions for peritrichia resulting in higher reproduction intensively and the increase of their population density. The research of peritrichous ciliates population density dependence on environment active reaction is done. In the research period pH index varied within 6,05-8,51. The dependence of population density on environment active reaction is not proved statistically (r = –0,25, р = 0,83). So, optimum conditions for peritrichia functioning in the river Uzh were temperature within 14-22 оС and dissolved oxygen content 8,4-10,3 mg/dm3. The direct dependence of peritrichous ciliates population density on the temperature (r = 0,74, р = 0,005) and the dissolved oxygen content (r = 0,51, р = 0,001) was established.