Intra-population spatial structure of the land snail &lt;i&gt;Vallonia pulchella &lt;/i&gt;(Müller, 1774) (Gastropoda; Pulmonata; Valloniidae)

Soil fauna is an important functional component of terrestrial ecosystems. Several hierarchical levels of spatial organization of pedobionts communities can be distinguished: point level, ecosystem level and landscape level. Of particular importance is the ecosystem level of spatial organization where the results of interaction between soil animals and soil and plant environmental factors, as well as the results of the influence of factors of neutral nature are expressed to the greatest extent. The aim of the work is to test the hypothesis that the spatial patterns of soil macrofauna at the ecosystem level can be explained by ecomorphs. Soil animals were sampled in floodplain ecosystems in the Dnieper River valley. Animals were sampled according to a regular grid with recording of local coordinates of sampling points. At the same points, soil properties were measured and geobotanical descriptions of vegetation were made. Phytoindication assessment of environmental factors was carried out on the basis of vegetation descriptions. The soil animal community is represented by high taxonomic and ecological diversity. The spatial distribution of soil macrofauna is not random and is a consequence of environmental factors and causes of a neutral nature. The ratio of these factors varies depending on the scale level. The fine-scale level is represented by factors of neutral nature. Medium- and broad-scale components are determined by soil and vegetation factors. The main spatial patterns of variation in the soil animal community correlate with the ecomorphic features of the animals. The ecomorphic approach allows interpreting the information on the spatial organization of pedobionts communities.

Section: Discussionmentioning

confidence: 99%

“…The species composition of communities according to niche theory can be explained by environmental variables [1,2]. Abiotic environmental factors act as ecological filters selecting those species appropriate to specific habitat conditions [3].…”

Section: Introductionmentioning

confidence: 99%

Spatial organization of the soil macrofauna community in a floodplain forest

Zhukova

Mytiai²

2022

“…The differences in observed soil penetration resistance values with varying water content and bulk density of different soils were attributed mainly to the influence of soil texture, organic matter and soil water retention curve [44,50,[59][60][61][62]. In spring after snowmelt and relatively low intensity of evaporation of moisture from the soil surface, the soil moisture content is significantly higher than in autumn [33,63]. The low precipitation in late summer and early spring, which is superimposed on the considerable intensity of moisture evaporation from the soil surface during the warm season, leads to a drastic reduction of its reserves in the soil [13,64].…”

Section: Discussionmentioning

confidence: 99%

“…These changes can reduce both the success of germination and the viability of rooted plants and can be detrimental to soil-dwelling organisms [31,32]. The soil penetration resistance was shown to be an important attribute of the ecological niche of mollusks under land reclamation [29,33]. Poor root development makes mature trees more susceptible to windthrow [34].…”

Section: Introductionmentioning

confidence: 99%

Effect of recreation on the spatial variation of soil physical properties

Telyuk

Malenko

Pozdniy

2022

Recreation affects various components of ecosystems. A significant transformation occurs in the soil cover in urban parks. The physical properties of soil are sensitive indicators of the level of anthropogenic transformation, and also allow to assess the state of soil as a habitat for plants and soil animals. The question of quantitative patterns of soil properties variability under the influence of recreation is not solved. There is also little information on the spatial aspect of the variability of soil physical properties in urban ecosystems. The aim of our study is to test the hypothesis that the recreational loads cause the formation of spatial patterns of soil properties, which by their extent greatly exceed the zone of direct influence. The spontaneous walkways within an urban park were investigated as an example of recreational loading. The physical soil properties were measured on a regular grid. The distance to the walkway was treated as a proxy variable that indicates recreational load. The application of multivariate statistical methods allowed to reveal the components of the variation of soil properties of different nature. The effect of recreational load is superimposed on the natural variability of properties. The peculiarity of the influence of recreation consists in sharp increase of soil penetration resistance in the upper soil layers and decrease of this index in the lower layers. The recreational load affects the physical properties of the soil. The soil compaction is the main direction of transformation. This effect gradually attenuates with distance from the source of exposure while occupying a significant portion of the space. The variation of soil properties affects the redistribution of soil moisture and soil air, which significantly affects the living conditions of soil biota.

“…Growth processes are quite sensitive to the slightest changes in any environmental factor, so the size and mass characteristics of animals placed in a poisoned environment are among the parameters that characterize the body's response to changes in water quality [35,36]. The freshwater pulmonates are one of the most commonly used taxonomic groups for toxic experiments because acute effects may be observed within a very short time [37,38]. Although chemical spills and other point sources of toxins can cause localized mortality in aquatic animals, freshwater snail populations may be declining as a result of the pervasive impacts of chronic, low-level contamination (Strayer et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

The growth characteristics and survival rates of great pond snail (Lymnaea stagnalis L.) juvenile under the heavy metal impact

Pinkina

Zymaroieva

Fedoniuk

et al. 2022

The study of the long-term effects of toxic substances, in particular, heavy metals, on aquatic organisms is currently a topical issue, due to the increase of anthropogenic pressure on the hydrosphere. The embryonic and juvenile stages of mollusks are more sensitive to toxic effects than adult ones. Consequently, the effects of different concentrations of heavy metal in the aquatic environment on the growth and survival rates of Lymnaea stagnalis juveniles were evaluated. In a chronic toxicological experiment, we used chronic lethal, sublethal, and subthreshold concentrations of heavy metals. We conducted 12 toxicological chronic experiments, lasting 60 days, with 1070 specimens of L. stagnalis juveniles. The toxic effect of heavy metals exposure in the aquatic environment in young individuals is manifested at much lower concentrations than in adults. The heavy metals ions affect the shell height of L. stagnalis juveniles even at the embryonic stage, which is manifested in some cases in the acceleration of their growth, in others – in its slowing down. The chronic experiment indicated that the values of shell height growth of juveniles in most cases correlate with the values of the total body weight growth. Under the influence of sublethal concentrations of heavy metal ions, the survival rates of juveniles are 3–4 times lower than the control. In solutions containing chronic lethal concentrations of Co2+ and Mn2+, up to 80–90% of juveniles die. The sharper and more rapid response of young snails to toxic effects compared to adult animals can be explained by embryo intoxication.