Changes in Biomass and Diversity of Soil Macrofauna along a Climatic Gradient in European Boreal Forests

Latitudinal gradients allow insights into the factors that shape ecosystem structure and delimit ecosystem processes, particularly climate. We asked whether the biomass and diversity of soil macrofauna in boreal forests change systematically along a latitudinal gradient spanning from 60° N to 69° N. Invertebrates (3697 individuals) were extracted from 400 soil samples (20 × 20 cm, 30 cm depth) collected at ten sites in 2015–2016 and then weighed and identified. We discovered 265 species living in soil and on the soil surface; their average density was 0.486 g d·w·m−2. The species-level diversity decreased from low to high latitudes. The biomass of soil macrofauna showed no latitudinal changes in early summer but decreased towards the north in late summer. This variation among study sites was associated with the decrease in mean annual temperature by ca 5 °C and with variation in fine root biomass. The biomass of herbivores and fungivores decreased towards the north, whereas the biomass of detritivores and predators showed no significant latitudinal changes. This variation in latitudinal biomass patterns among the soil macrofauna feeding guilds suggests that these guilds may respond differently to climate change, with poorly understood consequences for ecosystem structure and functions.

Ecomorphic Structure Transformation of Soil Macrofauna Amid Recreational Impact

The level of reacreation load on the components of urban green areas is increasing, so identifying the effective management tools in these ecosystems is becoming crucial for ensuring the maintenance of soil biota habitats. The purpose of this study is to reveal a pattern of structuring community of soil macrofauna under a recreational impact based on an ecomorphic approach. The article assesses the level of recreational transformation of the soil macrofauna of public green spaces in the city of Melitopol on the territory of Novooleksandrivskyi Park. For research purposes, a testing site was allocated in an area with a high level of recreational load, with samples taken within this site. To collect soil macrofauna and assess soil properties at each point of the testing site, soil and zoological tests were carried out and the following soil indicators were measured: temperature, electrical conductivity, humidity and soil penetration resistance, litter depth and grass stand height. The community ordination was performed using two approaches: OMI and RLQ analysis. The study found that the ecological niches of soil macrofauna in recreational conditions are spatially structured. The main factors for structuring the ecological niche of soil macrofauna within the study area are soil penetration resistance in the range of the entire measured layer, soil moisture, and distance to trees. As for the number of species, the basis of the coenomorphic structure of soil macrofauna are silvants (45.5%) and pratants (24.2%). As for the species abundance, the basis of the coenomorphic structure of macrofauna comprises pratants (64.5%), slightly less stepants (19.1%) and silvants (16.1%), and sporadic occurrence of paludants (0.2%). Such coenomorphic structure can be considered as ecologically labile. Zoophages, hemiaerophobes, and megatrophs are tolerant to a high level of recreational load. The area corresponding to the highest level of recreational load is vacant. This indicates factual absence of soil macrofauna species that could exist amid intense recreational exposure

Influence of scattered trees in grazing areas on soil properties in the Piedmont region of the Colombian Amazon

Trees dispersed in grazing areas are contribute to the sustainability of livestock systems. The interactions between trees and soil are ecological processes that allow the modification of the biology, fertility, and physics of the soil. This study was aimed to assess the influence of dispersed trees in pastures on soil properties in grazing areas for dual-purpose cattle systems in the Piedmont region of the Colombian Amazon. The work was done in grazing areas with scattered trees at the Centro de Investigaciones Amazónicas CIMAZ–Macagual in Florencia—Caquetá—Colombia. We evaluated the effect of five tree species, Andira inermis, Bellucia pentámera, Guarea Guidonia, Psidium guajava and Zygia longifolia, on soil properties (up to 30 cm soil depth) under and outside the influence of the crown. Under the tree crown, three points were systematically taken in different cardinal positions. This was done at a distance corresponding to half the radius of the tree crown. The sampling points in the open pasture area (out of crown) were made in the same way, but at 15 m from the crown border. The ANOVA showed significant interaction (P < 0.0001) between tree species and location for macrofauna abundance up to 30 cm soil depth. For this reason, we performed the comparison between locations for each tree species. Chemical soil variables up to 10 cm soil depth only showed interaction of tree species-location for exchangeable potassium (P = 0.0004). Soil physical soil characteristics up to 30 cm soil depth only showed interaction of tree species-location at 20 cm soil depth (P = 0.0003). The principal component analysis for soil properties explained 61.1% of the total variability of the data with the two first axes. Using Monte Carlo test, we found crown effect for all species. Trees help to control exchangeable mineral elements that can affect the soil, potentiate basic cations such as magnesium and potassium, increase the abundance of soil macrofauna; but some trees with high ground level of shade in grazing areas could increase soil compaction due to the greater concentration of cattle in these areas.

Soil Quality Restoration during the Natural Succession of Abandoned Cattle Pastures in Deforested Landscapes in the Colombian Amazon

Successional processes in abandoned pastures in the Amazon region have been well-documented for the floristic component; however, soil succession has been poorly studied. This study assessed the physical, chemical and biological responses of soils in the Amazon region during the natural succession process in two main landscapes of the Colombian Amazon. Soil data on soil physico–chemical (bulk density, macroaggregates, pH and minerals) and biological (soil macrofauna) composition were evaluated along chronosequence with four successional stages: (i) degraded pastures, (ii) young (10–20-year-old), (iii) middle-age (25–40-year-old) and (iv) mature forests, in two different landscapes (hill and mountain). Individual soil variables and a synthetic indicator of soil quality (GISQ) were evaluated as tools for natural succession monitoring. The results corroborated the negative impact that cattle ranching has on Amazon soils. After 10 years of natural succession, the physico–chemical and biological soil components were widely restored. Less soil compaction and organic carbon occurred in older successional stages. Soil macrofauna richness and density increased along the chronosequence, with an evident association between the macrofauna composition and the macroaggregates in the soil. None of the individual soil properties or the GISQ indicator discriminated among natural succession stages; therefore, new soil quality indicators should be developed to monitor soil quality restoration in natural successions.

Influence of durative drainage melioration on the soil macrofauna (The Leningrad region)

The soil-zoological research took place in 2018 on the territory of the soil-hydromeliorative station “Malinovsky” of Lisinsky educational-experimental forest farm (Tosnensky district, Leningrad region, Russia) which was drained in 1973-1974. The purpose of this research is a comparative evaluation of the density of the population and taxonometric variety of eco-functional groups of macrofauna on the Gleysols Histic Drainic after 45 year draining period and the similar biotop without drainage. The constitution of group and species and the trophic structure of soil macrofauna have been researched. 118 individuals of geobionts out of 3 types and 6 classes have been collected. It’s been stated that zoophages are the trophic dominating group. After 45 year draining period a poor groups and species constitution, a low number of large soil invertebrates and a small share of saprophages have survived which corresponds to the fauna of the soil in oligotrophic bogs.

Macrofauna evaluation in two coffee agroforestry systems

Knowing the soil macrofauna and its distribution is important to predict the degradation state of a soil as well as its physical properties and biological components. This research was carried out in coffee ecotopes 220A and 221A in southern Colombia. Two systems were evaluated, Coffea arabica var Castillo and native forest coffee, during two different seasons, winter and summer. Sampling was carried out using the tropical soil biology and fertility program (TSBF) methodology. The statistical treatment was carried out by means of a non-parametric analysis of variance Kruskal-Wall test. The density of orders present per square meter was evaluated, demonstrating that the highest density occurred in the winter season in the ecotope 220A and 221A forest system, with averages of 9.33 orders/ m2 and 9.67 orders/ m2, respectively. The highest number of density of individuals was obtained in winter, in the forest system and coffee in the 220A and 221A ecotopes with averages ranging between 1808 individuals/ m2 and 1368 individuals/ m2, statistically exceeding the number of individuals/ m2 that appeared in summer season. For biomass, the highest contribution was obtained in the winter season, with averages of 186.5 grams/ m2 in the 220A ecotope and 205.74 grams/ m2 for the 221A ecotope, exceeding the biomass that was presented in coffee winter season time, both in the 220A and 221A ecotopes.

Ligustrum lucidum invasion decreases abundance and relative contribution of soil fauna to litter decomposition but increases decomposition rate in a subtropical montane forest of NW Argentina

Invasive plant species can alter litter decomposition rates through changes in litter quality, environment conditions and decomposer organisms (microflora and soil fauna) but limited research has examined the direct impact on soil fauna. We assessed the abundance and relative contribution of soil meso- and macrofauna to litter decomposition in invaded forest by Ligustrum lucidum and non-invaded forest in a subtropical mountain forest of northwest Argentina using litterbags (0.01, 2 and 6 mm mesh size). Additionally, we analyzed litter quality and soil properties of both forest types. Soil fauna abundance was lower in invaded than in non- invaded forest. The contribution of soil macrofauna to litter decomposition was important in both forest types, but soil mesofauna contribution was only significant in non-invaded forest. Litter decomposition was significantly faster in invaded than in non-invaded forest, consistent with its highest quality. Invaded forest had significantly lower litter accumulation, lower soil moisture and greater soil pH than non-invaded forest. Our results showed that, although soil fauna was less abundant and played a less pronounced role in litter decomposition in invaded forest; these changes did not translate into a reduced litter decomposition rate due to the higher quality of litter produced in the invaded forest.