Groups Of Soil Fauna Research Articles

Impact of naphthalene on soil fauna diversity: Consequences for ecosystem functioning and carbon cycling in grasslands

Soil fauna, key indicators of grassland ecosystem health, face significant threats from the vast amounts of chemical pollutants released by human activities. These organisms are crucial for fundamental processes such as litter decomposition and carbon cycling. However, the response of soil animal communities and their functional dynamics to environmental chemical stress remains poorly understood. To investigate this, we conducted a naphthalene addition and litterbag experiment in the Bashang Grassland, located on the southern Inner Mongolia Plateau, to analyze its effects on soil fauna and litter decomposition. The investigated soil fauna groups included Arachnida (Arachnids), Insecta (Insects), Collembola (Springtails), Enoplea (enopleans), and Chromadorea (chromadoreans). The litter composition included Leymus chinensis, Stipa krylovii, Artemisia, Saussurea amara, and Artemisia giraldii. The findings indicated that a high diversity of soil fauna enhanced the decomposition of litter and the release of organic carbon from the litter. While the addition of naphthalene decreased both the abundance of soil fauna and the rate of litter decomposition, it specifically increased the relative proportion of Collembola (Springtails). Microfauna and mesofauna (0.1–2.0 mm) contributed more to the loss of litter mass and the release of organic carbon from the litter than macrofauna (2.0–4.0 mm). The effects of diverse soil fauna on litter decomposition and soil organic carbon accumulation were diminished by naphthalene exposure. This study further reveals the relationship between composite soil fauna diversity, litter decomposition, and soil organic carbon under chemical stress, highlighting the threat of environmental pollution to ecosystem health. It also enriches our understanding of the complexity of grassland ecosystems, especially in response mechanisms under chemical pollution stress.

Soil fauna changing in after‐pine harvesting's areas along a temporal gradient of Atlantic Forest regeneration

AbstractMonoculture of pine alters the soil fauna community structure, but forest farms, mixed with natural areas, are restoring the original vegetation to protect, the diversity and ecosystem functions. In restoration initiatives it is necessary to consider the soil fauna. Thus, the aim of this study was to investigate how the process of restoration of the soil community occurs over time in areas after pine harvesting. Areas in natural regeneration with 4 and 10 years, pine plantations adjacent to these areas (representing previous use), and areas of natural forest (reference) were evaluated, it was evaluated three areas per treatment, with six sampling points spaced 30 m apart, totalling 18 sampling points for each treatment (n = 18). Soil mesofauna and macrofauna were collected through soil monoliths and pitfall traps. The comparison of the statistical analysis was to check for changes in the soil fauna over time (4 and 10 years) compared with that observed in secondary forest areas. The study showed that, along the natural regeneration time (4 and 10 years), it was observed increments in the diversity and evenness of the soil community and a reduction in the dominance of groups like Formicidae and increases in the community structure complexity with the resurgence of micropredators/regulators (Collembola and Acari), litter transformers (Oligochaeta, Diplopoda, Blattodea, Coleoptera (Larva), Diptera (Larva) and Coleoptera) and predators (Pseudoscorpiones, Opiliones, Symphyla and Coleoptera) after 10 years of natural regeneration, the areas have already recovered groups with important ecosystem functions, but are not yet at the level of abundance, functional diversity and community structure of native forest areas. The 4‐ and 10‐year regeneration areas present major number of soil fauna groups of native forest (20 groups in regeneration areas and 17 in the native forest areas). Even so, the forest showed a major complexity of soil fauna community structure, evidenced by the diversity. This study contributes to the understanding of natural regeneration for soil fauna along a temporal gradient and these findings can guide the conservation of regional soil fauna diversity.

Rain gardens enhance the taxonomic richness but not the abundance of soil invertebrates in urban ecosystems

Natural treatment systems such as rain gardens aim to overcome the negative effects of urban stormwater, preventing harm to human population and infrastructure. Rain gardens house an abundance of soil fauna comprising a functionally important group of organisms. However, the responses of different groups of soil fauna to rain gardens remain poorly explored. In this study, we investigated the abundance, taxonomic richness, taxonomic diversity, and community composition of ground-dwelling and belowground invertebrates in rain gardens and nearby lawns in Nanjing and Zhenjiang cities, China. In Nanjing, we found that the taxonomic richness of ground-dwelling and belowground invertebrates was significantly higher in rain gardens than in lawns. We also discovered that the community composition of ground-dwelling invertebrates differed significantly between rain gardens and lawns, a distinction primarily explained by gravel coverage. However, in Zhenjiang, there were no significant differences in the abundance, taxonomic richness, taxonomic diversity, or community composition of ground-dwelling and belowground invertebrates between rain gardens and lawns. These results indicate that the effects of rain gardens on soil faunal community structure varied with soil fauna groups and cities. Considering that soil fauna have positive effects on the function of rain gardens such as water infiltration and decomposition, we suggest that the addition of ground surface mulch such as gravel may enhance soil biodiversity.

Tree species, mycorrhizal associations, and land-use history as drivers of cohesion in soil biota communities and microbe-fauna interactions

Community cohesion is a recent concept in ecology referring to the varying levels of connectivity and integration between populations of different taxonomic or functional groups within ecosystems. Positive cohesion denotes positive interactions such as mutualism or facilitation, while negative cohesion implies negative interactions such as competitive exclusion or a preference for different habitats. However, the effects of ecosystem characteristics such as tree species identity, mycorrhizal association and land-use history on soil biota community cohesion and microbe-fauna interactions remains poorly understood. We analyzed data on soil microbial biomass and biomass of taxonomic and functional groups of soil fauna obtained from monoculture stands of broadleaved tree species (maple and ash) associated with arbuscular mycorrhiza (AM), broadleaved tree species (beech, lime, and oak) associated with ectomycorrhizal fungi (ECM) and coniferous Norway spruce associated with ECM planted in common garden designs on former cropland and former forest land across Denmark. Our results revealed both positive and negative cohesion within soil communities, with only negative cohesion varying significantly among tree species. Soil biota communities under spruce indicated the most negative cohesion, whereas maple and ash soils showed least negative cohesion. Community cohesion varied across different sampling locations and between sites with different land-use histories. Positive cohesion was more pronounced in former cropland than in former old forest land, while negative cohesion was more pronounced in soils under tree species associated with ECM fungi than in soils beneath tree species associated with AM fungi. Both positive and negative cohesion were strongly influenced by litter chemistry and soil properties, indicating complex ecological dynamics. Soil pH, litter decomposition indices, and soil C:N ratio emerged as key drivers of microbial and faunal community structures. Additionally, the total microbial and faunal biomass, as well as the community structure of soil microbial and faunal communities, indicated strong positive interactions. Our results have the potential to support forest management by aiding in the selection of suitable tree species to support different groups of soil microbes and fauna, which play crucial role in ecosystem services such as nutrient release and transformation of soil organic matter.

Soil meso- and microfauna community acts as an environmental bioindicator in urban greenway landscapes

Urbanization accelerates habitat fragmentation and leads to the decline of biodiversity in cities. Urban greenway landscapes provide not only social functions but also important ecological services. In this study, taxonomic richness, abundance, diversity, and the distribution of soil meso- and microfauna were investigated in three different urban greenway landscapes to assess their environmental quality. Urban greenway landscapes that had a richer tree species composition, higher deciduous tree ratios, wider ecological greenspace, moderate soil temperature and moisture, and lower soil bulk density and less lead were conducive to the survival and development of the soil meso- and microfauna community. Different soil fauna groups had varied responses to different environmental conditions in urban greenway landscapes. Microarthropods were more sensitive to plant communities; in contrast, soil moisture was the most important abiotic driver for hygrophilous meso-micro fauna. Our study highlights the importance of deciduous trees for their rich litter input, and the wide ecological greenspace for its buffering effect on various disturbances, which promote the conservation of biodiversity in urban greenway landscapes.

Fast soil recovery after a fire: case study in Maritime Alps (Piedmont, Italy) using microarthropods and QBS-ar index

Soil is a very fragile ecosystem, often subject to many threats. Wildfires can affect edaphic communities depending on the intensity and seasonality of the fire. Different groups of soil fauna tend to respond differently to this type of disturbance, but the lack of data prevents to fully analyze the impact of fire. Soil microarthropods show a particular sensitivity to disturbances of different nature, making them excellent biological indicators. That is why in recent years many biotic indices to assess soil quality, like QBS-ar (Soil Biological Quality based on arthropods), have been developed. The objective of this study was to evaluate whether there might be a significant difference between areas affected or not by fire in the locality of Andonno (Piedmont, Italy) in terms of QBS-ar values, 18 years after this disturbance, and whether the reforestation intervention is having a positive effect on soil quality. Two sampling sites were selected within the sampling area and in each, six soil samples were taken. Microarthropods were extracted with a Berlese-Tüllgren extractor and soil biological quality was calculated using the QBS-ar index. No significant difference in QBS-ar values were found between the fire burned and unburned areas (p=0.37). The number of biological and euedaphic forms in the two sites was similar. It appears that microarthropod communities manage to recover in a short time, indicating that in the study area soil fauna has shown a fast recovery after extreme events like wildfires.

Collembola community contains larger species in frequently flooded soil

Climate change is increasingly affecting biotic communities, including soil fauna. Extreme weather events such as the incidence of heavy rainfall or prolonged drought can cause strong fluctuations in soil moisture. In river floodplains such extreme events determine the flooding intensity of the river bank grassland soils, and their communities. The diversity and distribution of many soil fauna groups depends on soil moisture content, so changes in inundation frequency and duration will impact soil fauna communities. We used the natural fluctuations in water levels of large Dutch rivers to investigate the effect of flooding intensity on the composition and traits of Collembola species, a key group of the soil fauna community. At five locations along large rivers in The Netherlands, we sampled Collembola communities at six levels of decreasing elevation and increasing flooding intensity. We identified all Collembola to species level and calculated species richness, composition and abundance values. Moreover, to understand the observed taxonomic changes across elevation we used the traits body size and life form to explain the change in Collembola community composition. Our results show that high flooding intensity favors larger Collembola species in the community. We hypothesize that high soil moisture in frequently flooded soil favors larger Collembola, which tolerate flooding. Life form, i.e. the preferred depth in the soil column, was significantly correlated with flooding intensity. There is an optimum in species richness and abundance at intermediate flooding intensity. These results can help predict the impact of climate change on soil fauna.

Impacts of long-term organic production on soil fauna in boreal dairy and cereal farming

Intensified arable farming results in fewer functional groups of soil biota with decreased biodiversity. Organic farming with slurry fertilization and long crop rotation cycles favors soil fauna diversity under tropical and temperate conditions. Faunal responses to agricultural practices in northern latitudes may, however, differ from those in southern latitudes due to different soil types, climatic conditions, and intensity of management. We investigated the abundance and diversity of soil fauna communities (nematodes, microarthropods, enchytraeids and earthworms) in a boreal sandy soil in replicated organically and conventionally cultivated field blocks that simulated cultivation in a cereal farm and in a forage producing dairy farm. In addition to traditional methods, we investigated nematode diversity using DNA metabarcoding. The results show that organic production system did not unequivocally result in higher abundance and diversity of soil fauna compared with conventional production systems, neither in the cereal nor the dairy farming type. Instead, abundances of all soil fauna groups were typically higher in the dairy than in the cereal farming type irrespective of production system. This holds up for all functional groups of nematodes except omnivores, all four orders of Acari present, two out of the six families of Collembola, the total number of enchytraeids and density of earthworms. Nematode diversity, measured as average ZOTU number, was in conventionally cultivated cereal farming type an order of magnitude lower than in other production and farming type combinations. Of the various differences between farming types, the crop species was the most important one as it defines the management practice and thus the soil conditions where soil biota lives. Our findings underline that when comparing soil faunal communities under organic and conventional cultivation, the differences between farming types need to be considered in addition to the production system as they can have an overriding importance across the food web.

Why phylogenetic signal of traits is important in ecosystems: uniformity of a plant trait increases soil fauna, but only in a phylogenetically uniform vegetation

Phylogenetically closely related plant species often share similar trait states (phylogenetic signal), but local assembly may favor dissimilar relatives and thereby decouple the diversity of a trait from the diversity of phylogenetic lineages. Associated fauna might either benefit from plant trait diversity, because it provides them complementary resources, or suffer from it due to dilution of preferred resources. We hence hypothesize that decoupling of trait and phylogenetic diversity weakens the relationship between the plant-trait diversity and the abundance and diversity of associated fauna. Studying permanent meadows, we tested for combined effects of plant phylogenetic diversity and diversity of two functional traits (specific leaf area, leaf dry matter content) on major groups of soil fauna (earthworms, mites, springtails, nematodes). We found that only in phylogenetically uniform plant communities, was uniformity in the functional traits associated with (i) high abundance in springtails, and (ii) high abundance of the sub-group that feeds more directly on plant material (in springtails and mites) or those that are more prone to disturbance (in nematodes), and (iii) high diversity in all three groups tested (springtails, earthworms, nematodes). Our results suggest that soil fauna profits from the resource concentration in local plant communities that are uniform in both functional traits and phylogenetic lineages. Soil fauna would hence benefit from co-occurrence of closely related plants that have conserved the same trait values, rather than of distantly related plants that have converged in traits. This might result in faster decomposition and a positive feedback between trait conservatism and ecosystem functioning.

Urban soil quality deteriorates even with low heavy metal levels: An arthropod-based multi-indices approach.

Urban-induced habitat conversion drastically changes soil life in a variety of ways. Soil sealing, human disturbance, habitat fragmentation, industrial and vehicular pollution are the main causes of urban soil degradation. Soil arthropods, as one of the most abundant and diverse group of soil fauna, are involved in many soil processes that are of great importance in maintaining soil health and multifunctionality. Nevertheless, soil quality is still mainly characterized by physical, chemical, and microbiological parameters. Here, we assessed and compared the biological soil quality in woody (REF: reference forest, REM: remnant forest) and nonwoody (TURF: public turfgrass, and RUD: ruderal habitat) types of urban green spaces along a disturbance and management intensity gradient in the Budapest metropolitan area (Hungary), using community metrics and soil arthropod-based indicators. Vegetation cover and landscape characteristics of study sites were quantified through vegetation and urbanization indices, respectively. Basic soil properties, total and bioavailable concentrations of the main heavy metals (Cd, Co, Hg, Ni, Zn) were also measured. Acari, Collembola, and Hymenoptera (mainly Formicidae) were the most abundant groups. Litter-dweller taxa, particularly Protura, proved to be the most sensitive to urban disturbance. Representatives of Hemiptera, Diptera, Symphyla, and Pauropoda were common in low densities. The taxonomic diversity of soil arthropod assemblages in nonwoody and woody habitats was similar. Although the integrated faunal indices showed no differences among soil habitat types, they provided different responses and, consequently, different information. Our findings demonstrated that the biological quality and arthropod community structure of soils were strongly impacted by soil C/N and heavy metal contamination. We found that low and moderate levels of pollution have adverse effects on edaphic fauna, suggesting biological degradation of soils, even below pollution limits. Nevertheless, more disturbed urban green spaces have been shown to play a significant role in maintaining belowground biodiversity, thereby soil functions.

Litter chemistry of common European tree species drives the feeding preference and consumption rate of soil invertebrates, and shapes the diversity and structure of gut and faecal microbiomes

Terrestrial isopods and millipedes are key drivers of a litter decomposition in terrestrial ecosystems but the effects of litter chemistry on feeding preference and litter consumption rate as well as on the diversity and composition of gut and faecal microbiome still entails several challenges. We established a mesocosm experiment with terrestrial isopods (Oniscus asellus) and millipedes (Glomeris marginata) fed by leaf litter from six common European tree species (ash, maple, lime, beech, oak and Norway spruce) to reveal the effect of litter chemistry on consumption rate and feeding preference as well as on the compositions of gut and faecal microbiomes. The total percentage of consumed litter showed that O. asellus preferred nutrient-rich and labile-C litter of ash over more recalcitrant litter of oak, beech, and Norway spruce, while G. marginata preferred calcium-rich ash, maple and lime litter over beech and Norway spruce. Consumption of litter by O. asellus and G. marginata increased with concentrations of magnesium, sulphur and potassium but decreased with concentrations of iron, phosphorus, lignin, cellulose and TOC. The millipede G. marginata harboured higher bacterial OTU richness (73.5 ± 12.5) than the isopod O. asellus (49.1 ± 15.9), but fungal OTU richness was similar with 25.8 ± 6.7 in O. asellus and 25.7 ± 2.7 in G. marginata. In total, faeces of both animals hosted higher diversity than gut. In gut and faeces of O. asellus, the fungal OTU richness was highest for individuals fed by litter of Norway spruce, while lowest OTU richness was recorded for individuals fed by litter of more palatable ash. In contrast, the highest diversity of the fungal community in gut and faeces of G. marginata was recorded for individuals fed by palatable lime litter, while the lowest OTUs richness was recorded when millipedes were fed by maple and spruce. The structures of bacterial and fungal communities generally separated between O. asellus and G.marginata. The fungal community structure in gut and faeces differed between animals fed by different foliar litters, while the bacterial community structure mainly differed between gut and faeces regardless of the offered type of litter. The fungal community structure in gut and faeces of O. asellus and G.marginata were shaped by concentrations of magnesium, sulphur, lignin and cellulose. The bacterial communities in gut and faeces of both O. asellus and G. marginata were dominated by copiotrophic bacteria, while fungal communities were dominated by unspecified saprotrophs. Our study suggest that litter quality is a strong driver of feeding preference and consumption rates as well as composition of bacterial and fungal communities in gut and faeces of two species representing the main groups of litter feeding soil fauna in European forests.

Performance assessment of a soil and water bioengineering work on the basis of the flora development and its associated ecosystem processes

The Atlantic Forest of Brazil is one of the world's 25 biodiversity hotspots, but floodplains in this region are continuously converted into agricultural or urban areas, and riverine ecosystems are affected by anthropogenic interventions. Soil and water bioengineering techniques are a component of ecological engineering that can provide nature-based solutions as an alternative or as complementary measures to conventional hydraulic or civil engineering approaches. However, there is a lack of post-evaluation of interventions and there are still great difficulties in identifying valid evaluation criteria and measurement variables, especially in countries like Brazil where soil and water bioengineering measures have only been implemented in the last decade. Another limitation to the widespread application of the techniques is the lack of knowledge about their technical performance, their impact on ecological processes and the evolution of the species used. This study aims to investigate the development of species, evaluate the technical performance of the intervention and assess the ecological benefits and processes of one of the first soil and water bioengineering riparian restoration interventions in Brazil, which was carried out in 2010 on the Pardinho river. Parameters on bank stability, development of species used in different construction techniques and its ecological benefits and ecological processes (plant species and soil fauna richness and diversity, ecological group and recruitment species, invasive species, soil organic matter and soil temperature) were collected over a period of ten years. The study proved that soil and water bioengineering works can both stabilise and control erosion, and at the same time initiate ecological processes on degraded riverbanks. The active introduction of native species has promoted vegetation succession, increased the biodiversity of both plants and soil fauna on the site and improved the site conditions. The establishment of native vegetation led to sediment and organic material deposition, which changed the local ecological conditions (e.g., soil properties, light, flow conditions) and thus facilitated rapid establishment of other plants and re-established interactions between plants and soil fauna groups. This study provides a monitoring approach which examines the technical performance of the measures and species used, as well as their impact on the ecological process over time, which is essential for establishing soil and water bioengineering techniques as the standard in the field of river engineering in Brazil. Furthermore, the results obtained will help in planning and designing future works in the field of soil and water bioengineering in Brazil, adding to the knowledge of the techniques and species to be selected, as well as supporting the evaluation of the success of interventions.

Global distribution of soil fauna functional groups and their estimated litter consumption across biomes

Soil invertebrates (i.e., soil fauna) are important drivers of many key processes in soils including soil aggregate formation, water retention, and soil organic matter transformation. Many soil fauna groups directly or indirectly participate in litter consumption. However, the quantity of litter consumed by major faunal groups across biomes remains unknown. To estimate this quantity, we reviewed > 1000 observations from 70 studies that determined the biomass of soil fauna across various biomes and 200 observations from 44 studies on litter consumption by soil fauna. To compare litter consumption with annual litterfall, we analyzed 692 observations from 24 litterfall studies and 183 observations from 28 litter stock studies. The biomass of faunal groups was highest in temperate grasslands and then decreased in the following order: boreal forest > temperate forest > tropical grassland > tundra > tropical forest > Mediterranean ecosystems > desert and semidesert. Tropical grasslands, desert biomes, and Mediterranean ecosystems were dominated by termites. Temperate grasslands were dominated by omnivores, while temperate forests were dominated by earthworms. On average, estimated litter consumption (relative to total litter input) ranged from a low of 14.9% in deserts to a high of 100.4% in temperate grassland. Litter consumption by soil fauna was greater in grasslands than in forests. This is the first study to estimate the effect of different soil fauna groups on litter consumption and related processes at global scale.

Biochar application differentially affects soil micro-, meso-macro-fauna and plant productivity within a nature restoration grassland

Biochar is proposed as an option to sequester carbon (C) in soils and promote other soil-based ecosystem services. However, its impact on soil biota from micro to macroscale remains poorly understood. We investigated biochar effects on the soil biota across the soil food web, on plant community composition and on biomass production. We conducted a field experiment in a nature restoration grassland testing four treatments: two biochar types (herbaceous feedstock pyrolyzed at 400 °C or 600 °C – hereafter B400 and B600), and a positive (i.e. unpyrolysed biochar feedstock, hereafter Hay) and negative (no addition) control. Responses of plants and soil biota were evaluated one and three years after establishing the treatments.Soil pH and K concentrations increased significantly in the B600 treatment. Mite abundances were significantly higher in B400 whereas nematode abundances were highest in Hay (1st year) and lowest in B400 (3rd year). Other soil fauna groups (enchytraeids and earthworms) varied more between years than between treatments. Legume cover increased significantly in the biochar treatments but this effect was transient. Legumes, grasses and primary productivity also showed a statistically significant Treatment x Year interaction due to transitory effects that were no longer present by the 3rd year.Our results suggest that biochar produced from meadow cuttings and applied at the 10 t/ha rate cause transitory impacts on soil biota abundance and plant communities over the 3-year timeframe used for this experiment. Therefore, this type of biochar could potentially be used for soil carbon sequestration, with minimal impacts on soil biota abundance or diversity, within the groups studied here, or plant biodiversity and productivity. Further research is required to investigate the longer-term impacts of this potential soil C storage sink.

Collembola are Among the Most Pesticide-Sensitive Soil Fauna Groups: A Meta-Analysis.

Pesticides are a major concern because of their deleterious impacts on biodiversity and on the ecological functions provided by living organisms. Although earthworms are well studied, smaller-sized organisms, such as Collembola, also contribute to the agroecosystem functioning, and their sensitivity to pesticides makes them good bioindicators of soil quality. Using data from 21 publications, we performed a meta-analysis to compare the pesticide sensitivity of Collembola with other soil invertebrate groups and discuss the relevance of including tests on representatives of this microarthropods group in European regulation tests. We defined a paired observation as the median lethal concentration or the median effect concentration values for both Collembola species and another soil fauna group (Acari, enchytraeids, earthworms, isopods, and nematodes) under a unique combination of author, year, substance, and type of soil (61 and 57 paired observations for reproduction and lethal effects). In some studies, paired comparisons were available for several groups of soil fauna. We demonstrated that Collembola are among the most sensitive soil fauna groups to a variety of pesticides, notably for effects on reproduction, mostly compared with earthworms and enchytraeids. Because there are several modes of exposure and explaining factors, we suggest moving from a single-species study to a food-chain approach integrating different taxonomic groups. Differences between soil fauna groups in sensitivity or response to pesticides could have effects on soil communities and also on soil functions. Environ Toxicol Chem 2022;41:2333-2341. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Distribution Patterns of Soil Fauna in Different Forest Habitat Types of North Hebei Mountains, China

The relationship between soil fauna distribution and forest habitat types is an ongoing concern. In this study, the distributions of soil fauna communities were investigated and compared in three forests of Betula platyphylla, Picea asperata, and Pinus sylvestris. A total of 39 groups of soil fauna belonging to four functional groups were found, with Acarina and Collembola being the dominant groups, and omnivorous and saprophagous being the dominant functional groups. An investigation on the temporal and spatial distribution of the soil fauna found similar changes in the three forests: the abundance of soil fauna was higher in August and September and lowest in May; explicit surface aggregation of the soil fauna emerged; and the density and group number decreased with the increase in soil depth. Via comparison, the total abundance of soil fauna in the B. platyphylla forest (16,772 ind m−2) was found to be higher than that in the P. asperata (12,972 ind m−2) and P. sylvestris (14,250 ind m−2) forests, and the indexes of diversity, richness and evenness of the soil fauna community in the B. platyphylla forest were the highest. Redundancy analysis showed that soil organic matter (SOC), total nitrogen (TN), and total phosphorus (TP) were positively correlated with soil fauna density, whereas pH and bulk density (BD) were negatively correlated. Compared with the two coniferous forests, the physicochemical factors positively (negatively) correlated with soil fauna density were the highest (lowest) in the B. platyphylla forest. The combined effect of these multiple factors suggests that the B. platyphylla forest recovered the most favorable conditions for the living and development of the soil fauna. The findings in this research may help us to understand the restoration effect of soil fauna in different forest habitat types, providing support for forest sustainable management in northern Hebei Mountain ecosystems.

Trait‐mediated responses to aridity and experimental drought by springtail communities across Europe

AbstractThe capacity to forecast the effects of climate change on biodiversity largely relies on identifying traits capturing mechanistic relationships with the environment through standardized field experiments distributed across relevant spatial scales. The effects of short‐term experimental manipulations on local communities may overlap with regional climate gradients that have been operating during longer time periods. However, to the best of our knowledge, there are no studies simultaneously assessing such long‐term macroecological drivers with local climate manipulations.We analysed this issue with springtails (Class Collembola), one of the dominant soil fauna groups, in a standardized climate manipulation experiment conducted across six European countries encompassing broad climate gradients. We combined community data (near 20K specimens classified into 102 species) with 22 eco‐morphological traits and reconstructed their phylogenetic relationships to track the evolution of adaptations to live at different soil depths, which is key to cope with desiccation. We then applied joint species distribution models to investigate the combined effect of the regional aridity gradient with the local experimental treatment (drought and warming) over the assembly of springtail communities and tested for significant trait–environment relationships mediating their community‐level responses.Our results show (1) a convergent evolution in all three major collembolan lineages of species adapted to inhabit at different soil strata; (2) a clear signature of aridity selecting traits of more epigeic species at a biogeographical scale and (3) the association of short‐term experimental drought with traits related to more euedaphic life‐forms.The hemiedaphic condition would be the plesiomorphic state for Collembola while the adaptations for an epigeic life would have been secondarily gained. Epigeic springtails are not only more resistant to drought, but also have a higher dispersal capacity that allows them to seek more favourable micro‐habitats after experiencing drier conditions. The observed relative edaphization of the springtail communities after short‐term experimental drought may thus be a transient community response.The disparity between macroecological trends and fast community‐level responses after climate manipulations highlights the need of simultaneously assessing long‐term and short‐term drivers at broad spatial scales to adequately interpret trait–environment relationships and better forecast biodiversity responses to climate change.Read the freePlain Language Summaryfor this article on the Journal blog.

Collembola dispersion, selection, and biological interactions in urban ecosystems: a review

Environmental and ecological degradation can be monitored by biological indicators such as plants, yet little research has been done using subterranean organisms such as collembola, especially in cities. Collembola, a soil fauna group, can be used to assess soil quality and to decipher assembly rules of soil organisms in cities. Here, we review 75 articles on soil collembola in an urban context. We found that soil properties and landscape characteristics influenced soil communities. There is a need for more connectivity between green urban spaces to allow the dispersion of collembola. Little information is available on the assembly of collembola communities, on biotic interactions and on dynamics of colonisation.

Biodiversity of collembola on green roofs: A case study of three cities in Belgium

Green roofs are often promoted as a mean to counter the negative environmental effects of urbanization on nature and to increase the amount of green space in cities. Green roofs often enhance aboveground biodiversity, especially herbivores and pollinators. However, if and in what way they support belowground biodiversity, and more specifically soil fauna, is rarely studied. Therefore, we evaluated the diversity of a dominant group of soil fauna, Collembola (springtails), on twelve extensive green roofs in three cities in Belgium (Antwerp, Ghent and Hasselt), over a one year period. The roofs differed in height above the ground, surface area, vegetation type, and age, i.e. time since construction. We analysed if these roof characteristics influenced species richness, abundance or diversity of Collembola. In total we found ten species of Collembola. Species richness was not higher on roofs that were larger (habitat area) or closer to the ground (isolation to surrounding soil), indicating that island-biogeographic theory is not applicable to species richness in our study system. However, significant differences in the mean number of individuals (abundance) were found between different months. Collembola taxonomical composition also varied between the roofs, but this variation could not be related to any of the measured roof variables. Roof communities were characterised by hemiedaphic life forms, preferring neutral to semi-moist conditions. Apart from the age of the roof that showed a positive significant impact on the abundance of Collembola present, our results suggested that the collembolan fauna showed no significant differences in abundance, species richness or diversity between roofs with different characteristics. However, we suggest that future studies are needed to investigate whether our findings are applicable to other groups of soil-living arthropods.

Unearthing soil arthropod diversity through DNA metabarcoding.

DNA metabarcoding has the potential to greatly advance understanding of soil biodiversity, but this approach has seen limited application for the most abundant and species-rich group of soil fauna–the arthropods. This study begins to address this gap by comparing information on species composition recovered from metabarcoding two types of bulk samples (specimens, soil) from a temperate zone site and from bulk soil samples collected at eight sites in the Arctic. Analysis of 22 samples (3 specimen, 19 soil) revealed 410 arthropod OTUs belonging to 112 families, 25 orders, and nine classes. Studies at the temperate zone site revealed little overlap in species composition between soil and specimen samples, but more overlap at higher taxonomic levels (families, orders) and congruent patterns of α- and β-diversity. Expansion of soil analyses to the Arctic revealed locally rich, highly dissimilar, and spatially structured assemblages compatible with dispersal limited and environmentally driven assembly. The current study demonstrates that DNA metabarcoding of bulk soil enables rapid, large-scale assessments of soil arthropod diversity. However, deep sequence coverage is required to adequately capture the species present in these samples, and expansion of the DNA barcode reference library is necessary to improve taxonomic resolution of the sequences recovered through this approach.