Microhabitats and oribatid fauna: comparison of 2 sampling approaches

Abstract

Oribatid fauna highly varies among habitats, but different microhabitats within a habitat are also characterized by different mite species. The main goal of the research was to compare the observed structure of an oribatid community when samples were collected at random from the soil-litter layer of 0-10 cm in depth (standard approach) and selectively from 6 types of available microhabitats (complex approach). Samples were taken within a small plot (10 m × 10 m) in a forested area of the Silesian Park (Chorzów, south Poland). Overall, 2642 specimens of Oribatida belonging to 62 species were collected in 66 samples. The structure of the oribatid community observed by means of the 2 sampling approaches was completely different. The abundance and species richness of oribatid mites collected from 6 microhabitats were significantly higher than in the soil-litter layer alone. Results of this study show that random collecting of only soil-litter samples may reduce the evaluation of species richness in a study area by 40%. Each of the studied microhabitats supported a peculiar oribatid fauna.

High Diversity of Mites (Acari: Oribatida, Mesostigmata) Supports the High Conservation Value of a Broadleaf Forest in Eastern Norway

“…Another extensive study was carried out in ten broadleaf forests in Ireland, where two forest types, nine microhabitats and two sampling methods were applied, but despite higher sampling effort the number of mite species (Oribatida and Mesostigmata) was lower there and varied between 18-75 per forest [126]. When only the soil microhabitat was sampled [123,124,127], the number of species of Oribatida per 500 cm 3 sample was lower than in our study, which underscores the importance of sampling different microhabitats for biodiversity assessment [12,15,21,37,[128][129][130]. Many new species records for Norway come from specific microhabitats which illustrates the importance of sampling a broad range of microhabitats in studies of faunal inventories and diversity assessment.…”

“…Due to their small body size, they often go unnoticed, although they live in diverse forest microhabitats-from deep soils, even 2-3 m underground [10], up to the tops of trees [11]. They are usually most abundant and species-rich in mosses [12][13][14][15].…”

Type of broadleaf forest matters most for ptyctimous mite communities (Acari, Oribatida) in Norway

“…Since not all Phthiracaridae were identified to species level in that study, it is not possible to compare the richness of this group across microhabitats. In fact, Oribatida as a total are usually most abundant and species-rich in mosses (e.g., Skubała 2016;Seniczak et al 2018Seniczak et al , 2019a.…”

Seasonal fluctuation of oribatid mite communities in forest microhabitats

“…All community parameters (abundance, species richness, diversity) confirmed former studies. The presence of a highly abundant oribatid mite community in mosses is well known ( Aoki, 1967 ; Glime, 2013 ; Skubala, 2016 ; Wehner et al, 2016 ). Many oribatid mite species use mosses as microhabitat during their life cycle, for food or shelter, and associations can even be mutualistic ( Cronberg, Natcheva & Hedlund, 2006 ; Glime, 2013 ).…”

“…Microarthropods were extracted for 48 h using a modified Kempson heat extractor ( Kempson, Llyod & Ghelardi, 1963 ) and stored in 75% ethanol. Samples were weighed after extraction and dry weights of samples were used to standardize the number of individuals as Ind/kg dry weight following ( Skubala, 2016 ) (dry weights can be found in Table S1 ). Adult oribatid mites were determined to species, genus or family level under a microscope using the key of Weigmann (2006) .…”