Patterns of Benthic Fauna Distribution in Wells: The Role of Anthropogenic Impact and Geology

Abstract

Core Ideas Geology does not seem to influence fauna composition in the studied wells. Water chemistry does not differ significantly in wells placed on limestone and flysch. Water pollution affects the abundance and diversity of wells fauna. Fauna distribution depends mainly on depth and age of the wells. Surface water fauna prevail; only three stygobiontic species were found. This study was undertaken to determine the factors that influence the composition of macroinvertebrate communities in wells completed into two different bedrocks, limestone and flysch. The chemical parameters of the water in wells of both kinds did not significantly differ. The anthropogenic impact on the quality of water was revealed in some wells in both areas, which resulted in relatively low fauna diversity and abundance in polluted wells. Canonical correspondence analyses suggested that depth, age, sediment organic matter content, water oxygenation, and conductivity best explained the variance in the distribution of benthic fauna taxa. Among the 19 taxa that were determined to the family level, oligochaetous Clitellata dominated. They were represented by 13 species and one genus. Among them, two stygobionts, Trichodrilus moravicus and Rhyacodrilus subterraneus, were determined. Moreover, only one crustacean stygobiont, Niphargus tatrensis, was found, and it occurred only in a single well. A low number and abundance of stygobionts and stygophiles compared with stygoxenes was observed. Our studies showed that bedrock substratum does not influence macroinvertebrate composition.

Diversity of Groundwater Crustaceans in Wells in Various Geologic Formations of Southern Poland

“…The subterranean fauna dwells in underground waters such as caves, interstitial waters, wells, as well as other man-made subterranean habitats such as adits, shafts or mines. It also occurs in springs [3].…”

“…Methods used for analyses of physical and chemical water feature analyses of the investigated wells have been described in Dumnicka et al [3]. The results of studies on benthic invertebrates other than Crustacea (Copepoda and Ostracoda) from the same wells have already been published [3], while the data on plankton samples from wells from the area of Jaszczurowa village were presented as a conference poster [39].…”

“…(2) -as Diacyclops clandestinus (Kiefer, 1926) in [56]. (3) -as Diacyclops languidus disjunctus (Thallwitz, 1927) in [57]. (4) -as Cypricercus affinis (Fischer, 1851) in [24].…”

“…The subterranean aquatic environment represented by cave waters, dug or drilled wells, interstitial waters and hypotelminorheal [1] is the habitat of a range of invertebrates. Among them, crustaceans arprovude the largest number of stygobiontic species [1][2][3] often accompanied by epigean species.…”

“…Access to them gives the possibility to study subterranean aquatic invertebrates in regions of different geological character, even in areas without caves. During the macroinvertebrate studies from 26 wells in southern Poland, only one crustacean species Niphargus tatrensis was determined [3].…”