Agrology (Sep 2019)
Spatial organization of the Vallonia pulchella (Muller 1774) ecological niche in sod-lithogenic soils on loesses-like clays in the Nikopol Manganese Ore Basin
Abstract
The influence of edaphic and phytoindication parameters on the spatial organization of the micromollusc Vallonia pulchella (Muller 1774) ecological niche was experimentally investigated. The field experiment was conducted in June 2015 at the research polygon within the Nikopol Manganese ore basin (sod-lithogenic soils on loam loesses-like clays). A promi-sing area of research is the issue: what exactly edaphic factor and phytoindication parameters is the most important determinants of micromolluscs distribution. The experimental polygon was consisted of 105 samples located within 7 transect (15 samples each). The Vallonia pulchella average density was 2.54 ind./sample. The average penetration resistance of the soil was found as a result of the experiment studies to increase with depth down the profile. The analysis of aggregate fractions showed that the number of molluscs is unstable and varies in the range of 5.17% to 25.45%. The snails were found to prefer the aggregate fractions 1‒2 mm or in less extent – the 0.5–1.0 mm. The elevated level of carboxylic salts was detected by means of phytoindication methods as well as the insignificant content of free nitrogen in neutral soil. In the paper the soil and vegetation properties were considered as a indicators of the living organism habitats. It allowed to assess the Vallonia pulchella ecological niche marginality and specialisation. The results obtained may be usful in the evaluation of artificial soil structures.
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