Food Offer Inside Agroecosystem Soils as an Ecological Factor for Settling Microhabitats by Soil Saprophagous Mites

Abstract

Mainly abiotic factors have been considered in examining soil fauna invasion or settlement. The role of soil animals communities was not considered. Our hypothesis, indeed, can be formulated: the structure and feeding habits of the soil animals community is not able to play some role in the soil rating. Localities, however, can be fragmented into microhabitats. We studied cultivated fi eld and adjacent unploughed areas (so-called baulks), using the common Berlese-Tullgren apparatus for community structure studies followed by histological tests of food consumed by community members. We selected a group of oribatid mites, which are frequent and abundant. In the studied localities and their microhabitats, three groups of oribatid mites can be reported. First -ubiquitous species a secondmigrants from the less-impacted to more-impacted microhabitats and third -specialists sensitive to severe environmental conditions in more-impacted microhabitat. They consequently live only in the less-severe, less-impacted unploughed soils and never migrate from these microhabitats. Their grazed and digested food is more diversifi ed, and they included more feeding specialists.

Microhabitats and oribatid fauna: comparison of 2 sampling approaches

“…aoKi (1974) observed that each of the studied microhabitats in forest floors contained a peculiar oribatid fauna. The same phenomenon was reported by Smrž et al (2015) with regard to soil microhabitats in agroecosystems. nielsen et al (2010) provided direct evidence for the hypothesis that small-scale heterogeneity in soils increases the species richness of intermediate-sized soil fauna, including oribatid mites.…”

Influence of 90-year potato and winter rye monocultures under different fertilisation on soil mites

“…This could be caused by environmental factors, especially soil pH (Zhang et al 2015) or soil moisture (Sylvain et al 2014). Another reason could be the food supply inside the ecosystem and the level of microhabitat transformation (Smrž et al 2015). The belowground source of organic matter like decaying roots often shows the heterogeneity of spatial patterns, which corresponds with the spatial patterns of mites (Ducarme & Lebrum 2004).…”

“…However, as described by Gergós and Hufnagel (2009), the response of Oribatida to different environmental factors, such as temperature, heavy metal concentration, organic matter content or agricultural management, is usually complex and needs wider studies. For example Smrž et al (2015), analysing the migration of Oribatida between arable field and unploughed area, distinguished groups with different levels of adaptation from ubiquitous species to specialist ones. Another study of this author (Smrž 1996) showed differentiated adaptation of Oribatida to extreme moisture conditions.…”