We studied communities of macrophytes and macroinvertebrates in selected ponds on the Karst plateau. 16 locations were chosen from older graduation thesis, so we could compare the changes of certain parameters and community structure of macrophytes in 12 years. During the fieldwork, we assessed the catchment area of each pond, measured environmental parameters, made an inventory of macrophytes, took samples of macroinvertebrates and checked if there are any fishes in the ponds. We determined concentrations of nitrates and phosphates in the laboratory. We performed statistical analyses with collected data, calculated diversity indices and made direct gradient analysis to see which parameters shape the structure of the studied communities. In general, we measured high concentrations of nutrients in Karst ponds, the concentration and saturation with oxygen mostly depended on presence of primary producers, we also measured high water temperatures, which is typical for this shallow ecosystems in the summer. In total, we found 44 taxa of macrophytes. Land use of the catchment area and Secchi depth influenced the composition of macrophyte communities. We found a total of 28 families of macroinvertebrates. In one pond only 1 family was found, but in most diverse pond we found 16 families. Communities of macroinvertebrates are shaped by electroconductivity, presence of fish, concentration of chlorophyll a and temperature. We found fish in 4 ponds.
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