Oribatid mite species numbers increase, densities decline and parthenogenetic species suffer during bog degradation

Abstract

This study compared the oribatid mites in two natural and four industrially exploited bogs. One natural bog (Zakręt, Z) was located in northeastern Poland and the other one (Toporowy Staw Niżni, TSN), in southern Poland. The four exploited bogs were also located in southern Poland and can be ranked from least to most degraded as follows: Łysa Puścizna (LP), Baligówka (B), Puścizna Mała (PM) and Kaczmarka (K). In the natural bogs, the water pH was higher than in the degraded ones, but other parameters were lower (conductivity, colour value, oxygen demand, and concentration of chlorides). In the natural bogs, the Oribatida were highly abundant (average density was 169,100 ind./m(2)), but with low species diversity and one dominating species. In bog Z the most abundant was Limnozetes foveolatus that had dominance of 75 % and in bog TSN, located at higher altitude, Trimalaconothrus maior dominated (73 %). In two degraded bogs that had still good water conditions (LP and B) the oribatid communities resembled those from the natural bogs; in LP the most abundant species was Hydrozetes lacustris and in bog B, L. foveolatus. In contrast, in two more degraded bogs (PM and K) the abundance of mites was lower (average density was 17,850 ind./m(2)), species diversity of the Oribatida was higher, and no species achieved a high dominance like in the natural bogs. Additionally, in more degraded bogs the abundance of parthenogenetic species was lower than in the natural bogs.

Parthenogenetic vs. sexual reproduction in oribatid mite communities

“…Furthermore, the percentage of sexual species (as well as individuals) decreases with increasing altitude up to about 3,000 m in tropical as well as temperate regions (Fischer, Meyer, & Maraun, 13; Maraun et al, 33), but in the Andes at 4,000–5000 m it is lower than at 3,000 m (Covarrubias, 8; Hense, 21; Maraun et al, 33). The dominance of parthenogenetic species at very high altitudes in the Andean mountains probably is due to the fact that peatland vegetation dominates at these sites which are colonized by oribatid mite communities similar to those of peat bogs from lowland sites at high latitudes (Lehmitz & Maraun, 29; Mumladze, Murvanidze, & Behan‐Pelletier, 42; Seniczak, Seniczak, Maraun, Graczyk, & Mistrzak, 55). The reduced frequency of sexual species at very high altitude conforms to predictions of both the RQT as well as the SRTS since they suggest that harsh environmental conditions foster parthenogenesis by reducing parasite–host interactions and by reducing density‐dependent population regulation, respectively.…”

Comparison of Sporormiella dung fungal spores and oribatid mites as indicators of large herbivore presence: evidence from the Cuzco region of Peru

“…Another hypothesis for changes in Hydrozetes numbers is that camelid dung and urine altered the prevailing water quality, again through run-off from the land or direct deposition into the lake. Indeed, data from ecological studies of extant populations show that Hydrozetes species vary greatly in their tolerance to different environmental conditions, including pH levels, and amounts of available oxygen, biodegradable organic matter, suspended particles and conductive ions from dissolved salts and inorganic materials (Seniczak, 2011, Seniczak et al 2013, 2016b. In general, however, Hydrozetes are more likely to reflect more nutrient-rich, eutrophic conditions; compare this with the charophyte and diatom records, which tend to indicate when the lake was shallow and oligotrophic.…”

<p><strong>Checklist of oribatid mites (Acari: Oribatida) from two contrasting boreal fens: an update on oribatid mites of Canadian peatlands</strong></p>

“…The work of Belanger (1976) is still the most comprehensive study documenting 44 species in a Sphagnum-dominated fen in New York State, of which 25 species had been previously recorded from European peatlands. In Europe, however, oribatid mites in peatlands have been and continue to be much more intensively studied (Borcard & Matthey 1995;Borcard & Vaucher-von Ballmoos 1997;Ivan et al 1997;Laiho et al 2001;Ivan & Călugăr 2003;Starý 2006;Sidorchuk 2008;Mumladze et al 2013;Markkula 2014;Lehmitz 2014;Melekhina et al 2015;Minor et al 2016Minor et al , 2019Seniczak et al 2016Seniczak et al , 2019Seniczak et al , 2020Lehmitz & Maraun 2016;George et al 2017;Markkula et al 2019;Juan-Ovejero et al 2019;Lehmitz et al 2020). In addition, subfossil oribatid fauna from European peatlands are also thoroughly investigated (Karppinen et al 1979;Cañellas-Boltà et al 2012;Markkula 1986;Markkula 2020;Markkula et al 2018).…”