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This piece is about a close encounter between the mole and archaeologists. This is nothing new. Archaeologists are accustomed to taking the "disturbances" that moles produce into account in their working assumptions. Indeed, archaeologists tend to agree with other soil practitioners such as farmers and gardeners that moles are a pest for perturbing soils. The market is abrim with all sorts of pungent flower bulbs, devices that emit vibrations, gas, or explosives that flood, pinch and trap moles. This piece centres on a very specific context, a research group based at Ghent University studying the site of a medieval settlement north of Bruges where archaeologists work with the shards of pottery contained in the soils moles bring to the surface. In their research, the assumption that moles are a nuisance is suspended by engaging molehills in a new but low-tech scientific practice. This piece tackles the wider question of what a pest is by enrolling the practice of these archaeologists into a history of multi-species social science perspectives. It thinks through the dynamics of categories that species come up against and slide in and out of (Haraway 2008). It is, therefore, a piece about more than human species. It is also a piece about soils. The soils that emerge involve many different species and not just humans but other living beings including moles, worms, badgers, insects, and plants. Lending attention to soils brings with it socio-cultural associations, tools such as sieves, and legislations about animals and archaeological digs. Densely inhabited and littered with remnants of human activities and histories, we might call these multispecies social soils. [ABSTRACT FROM AUTHOR]

Zero Budget Natural Farming (ZBNF), utilizing natural resources, multiple cropping systems, and cow-dung- and urine-based products to improve soil biology, has been practiced by thousands of farmers in India. However, without any scientific proof, this traditional and ancient technique is mocked as a bugged theory in the scientific community. In the current study, we have investigated the effect of Jeevamrit—cow-dung- and urine-based formulation—on soil chemical and microbial properties of the ZBNF field coupled with metagenomic analysis and the economics of ZBNF. The percentage increase in soil properties, such as organic carbon, available phosphorus, and available potassium, was recorded up to 46%, 439%, and 142%, respectively, while micronutrients, such as Zn, Fe, Cu, and Mn, also increased up to 98%, 23%, 62%, and 55%, respectively, from 2017 to 2019. Whole genome metagenomic analysis revealed that Proteobacteria were dominantly present, and bacterial phyla including Bacillus, Pseudomonas, Rhizobium, and Panibacillus. On the other hand, Ascomycota was the dominating fungal phyla present in the soil sample. Further, functional analysis showed a high representation of genes/enzymes involved in amino acids and carbohydrate metabolism contributing to soil fertility, plant growth, defense, and development. Additionally, the cost–benefit ratio of ZBNF was double the farmer's practice when tested with the rice and wheat cropping system. The results from this study provide a new proof of concept and understanding of the potential of the ZBNF component, i.e., Jeevamrit, in improving soil properties. [ABSTRACT FROM AUTHOR]

Aspergillus unguis belongs to the Aspergillus section Nidulantes. This species is found in soils and organisms from marine environments, such as jellyfishes and sponges. The first chemical study reported in the literature dates from 1970, with depsidones nidulin (1), nornidulin (2), and unguinol (3) being the first isolated compounds. Fifty-two years since this first study, the isolation and characterization of ninety-seven (97) compounds have been reported. These compounds are from different classes, such as depsides, depsidones, phthalides, cyclopeptides, indanones, diarylethers, pyrones, benzoic acid derivatives, orcinol/orsenillate derivatives, and sesterpenoids. In terms of biological activities, the first studies on isolated compounds from A. unguis came only in the 1990s. Considering the tendency for antiparasitic and antibiotics to become ineffective against resistant microorganisms and larvae, A. unguis compounds have also been extensively investigated and some compounds are considered very promising. In addition to these larvicidal and antimicrobial activities, these compounds also show activity against cancer cell lines, animal growth promotion, antimalarial and antioxidant activities. Despite the diversity of these compounds and reported biological activities, A. unguis remains an interesting target for studies on metabolic induction to produce new compounds, the determination of new biological activities, medicinal chemistry, structural modification, biotechnological approaches, and molecular modeling, which have yet to be extensively explored. [ABSTRACT FROM AUTHOR]

Sulfate is an essential macroelement for all living organisms. However, sulfate can be limited in agricultural settings. Microorganisms change their gene expression to acclimate to sulfate deficient conditions. Green microalga Chlamydomonas reinhardtii expresses and secretes extracellular arylsulfatase (ARS) under sulfate deficient conditions. Our results show that C. reinhardtii ARS can hydrolyze both sulfate monoester (5-bromo-4-chloro-3 indolyl sulfate; X-SO42-) and phosphate monoester (5-bromo-4-chloro-3 indolyl phosphate; X-PO43-) providing evidence that ARS enzyme has promiscuous activity. C. reinhardtii is found in soil and fresh water habitats in nature. This promiscuous activity can be beneficial in making both sulfate and phosphate bioavailable for uptake by soil organisms and plant roots. [ABSTRACT FROM AUTHOR]

We report the first isolation of a widely distributed free-living soil amoeba Leptomyxa (Amoebozoa, Leptomyxida) from endozoic conditions. The amoebae were detected after 14 days following inoculation of the intestine of the earthworm Lumbricus terrestris on an agar plate with Escherichia coli. The earthworm was collected from Calcaric Fluvisol (pH 7) in the Upper Váh region, north-west Slovakia. Observed amoebae were uninucleate, polypodial with typically branched pseudopodia, and morphologically resembled Leptomyxa australiensis. This study enlarges the range of amphizoic tendency in leptomyxid amoebae and indicates their interactions with Oligochaeta. [ABSTRACT FROM AUTHOR]

The recent and widespread use of engineered nanomaterials in many industrial sectors is a rising health issue for living organisms and ecosystems, yet there is limited knowledge on nanomaterial toxicity, especially in complex soil systems. Here we review the fate of engineered nanomaterials in soils, their toxicity for soil organisms, and soil factors controlling their toxicity. We discuss nanomaterial toxicity for microorganisms, invertebrates, and terrestrial plants. Toxicological mechanisms include membrane damage, metal ion release, oxidative stress, and metabolic disorders. Toxicity-controlling factors include soil physicochemical properties, soil organic matter, and coexisting contaminations. [ABSTRACT FROM AUTHOR]

The field trials on terminal residue and dissipation of difenoconazole in celery were carried out in Hunan and Shandong Provinces, and the acute toxicity of 10% difenoconazole water dispersible granule (WG) on soil organisms were studied in the laboratory. Based on the residue data and toxicity endpoints, the long-term and short-term dietary intake risks of difenoconazole to different populations in China and the environmental risks to soil organisms were evaluated. The results showed that the halflife of difenoconazole in celery leaves, stems and soil were 5.2-8.8 d, 8.0-8.2 d and 13.6-15.0 d, respectively. After the formulation was applied for three times with the interval of 5 days at the recommended dosage of 120 g/hm2, the residue of difenoconazole in celery leaves was higher than MRL (3 mg/kg, China) and the residues in celery stem and the whole celery seedling were less than MRL on the 5th day after last application. The short-term dietary intake risk quotient (RQa ) for the general population and children aged 1-6 years were 0.09 and 0.10, respectively. The long-term dietary risk assessment results showed that the contribution rate of the residues in celery for different populations in China was 9.4%-19.8%. The primary risk of 10% difenoconazole WG to soil organism was acceptable with acute risk quotient (RQe ) of 0.368-0.890. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a biologically non-essential element in the soil that brutally affects plants and other living organisms in soil; hence, its removal has become a worldwide concern. In this work, a multifunctional nanoscale zerovalent-iron assisted biochar (nFe°/BC) was used to minimize the Pb bioavailability in soil with aim of alleviating the Pb-induced toxicity in sunflower. Results revealed that nFe°/BC treatment had significantly improved plant growth (58%), chlorophyll contents (66%), intracellular permeability (60%), and ratio factor (93%), while decreasing the Pb uptake (78%) in plants. The Pb-immobilization and transformation mechanisms were proposed, suggesting that the presence of organic functional groups over the nFe°/BC surface might induce the complex formation with Pb by the ions exchange process in soil solution. The XPS analysis confirmed that surface-active components (Fe+, O2−, O*, C═O) were the key factor for high Pb-immobilization within soil matrix. In addition, 87% of stable Pb species, including PbCO3, PbO, Pb (OH)2, and Pb-O-Fe were found in the soil surface. Current findings have exposed the diverse functions of nFe°/BC on plant health and established a phenomenon that nFe°/BC application could improve the plant agronomic attributes by regulating the homeostasis of antioxidants and Pb uptake. [ABSTRACT FROM AUTHOR]

Ecosystems shaped by retreating glaciers provide a unique opportunity to study the order and timing of biotic colonization, and how this influences the structure of successive ecological communities. In the last century glaciers across most of the cryosphere have receded at an unprecedented pace. Many studies have been published from different parts of the world testing hypotheses about how soil ecosystems are responding to rapid, contemporary deglaciation events. To better understand and draw general conclusions about how soil ecosystems respond to deglaciation, we conducted a global meta‐analysis of 95 published articles focused on the succession of various organisms and soil physicochemical properties in glacier forefields along the chronosequence. Our global synthesis reveals that key soil properties and the abundance and richness of biota follow two conspicuous patterns: (1) some taxa demonstrate a persistent increase in abundance and richness over the entire chronosequence, (2) other taxa increase in abundance and richness during the first 50 years of succession, then gradually decline 50 years onward. The soil properties and soil organisms that are intimately tied to vegetation follow the first pattern, consistent with the idea that aboveground patterns of vegetation can drive patterns of belowground biodiversity. The second pattern may be due to an initial increase and subsequent decline in available nutrients and habitat suitability caused by increased biotic interactions, including resource competition among soil biota. A consensus view of the patterns of historical and contemporary soil ecosystem responses to deglaciation provides a better understanding of the processes that generate these patterns and informs predictions of ongoing and future responses to environmental changes. [ABSTRACT FROM AUTHOR]

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Massive quantities of energy flow through soils during a year. Emerging views indicate that when supplied with abundant energy, soil biology acts as a self‐organizing system as soil microbes forge their habitats into a porous, well‐aggregated structure with high functionality. The flow of energy to power these self‐organizing processes has not been accounted for in present soil models, which concentrate on static pools of soil organic matter (SOM) and carbon and their relationship to soil functionality. To address this, we introduce a new conceptual energetics framework that quantifies the net energy flows within a soil control volume (CV) using a suite of energetic components including mechanical, biogeochemical, and hydrological processes. This framework is presented at a conceptual level and can be expanded to more granular levels with further study. To assess its present capabilities, management systems of conventional‐till (CT) and no‐till (NT) corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotations and a grassland system (GS) were evaluated using the model. Net energy fluxes over a growing season were found to be negative for the CT, net zero for NT, and positive for GS. The energetics framework shows it can provide a first‐order assessment of soil health and advise which management practices provide adequate supplies of energy to soil biology to effectively enhance soil functionality. Core Ideas: Net positive supplies of energy support biological systems capable of altering the soil structure.Management practices impact energy fluxes through tillage type and intensity and raindrop‐induced erosion events.An energetic framework is proposed that is applied to three different management practices to assess energy balances.Seasonal net energy balances for conventional till, no till, and grassland system were negative, neutral, and positive, respectively. [ABSTRACT FROM AUTHOR]

Excessive application of fungicides in crop fields can cause adverse effects on soil organisms and consequently affect soil properties. Existing knowledge on the effects of strobilurin fungicides has been primarily based on toxicity tests with active ingredients, while the effects of fungicide formulations remain unclear. Therefore, this work aims to provide new data on the effects of three commercial formulations of strobilurin fungicides on the soil organism Enchytraeus albidus. The tested fungicide formulations were Retengo® (pyraclostrobin—PYR), Zato WG 50® (trifloxystrobin—TRI) and Stroby WG® (kresoxim-methyl—KM). In laboratory experiments, multiple endpoints were considered at different time points. The results showed that PYR had the greatest impact on survival and reproduction (LC50 = 7.57 mga.i.kgsoil−1, EC50 = 0.98 mga.i.kgsoil−1), followed by TRI (LC50 = 72.98 mga.i.kgsoil−1, EC50 = 16.93 mga.i.kgsoil−1) and KM (LC50 = 73.12 mga.i.kgsoil−1, EC50 ≥ 30 mga.i.kgsoil−1). After 7 days of exposure, MXR activity was inhibited at the highest concentration of all fungicides tested (6 mgPYRkgsoil−1, 15 mgTRIkgsoil−1 and 30 mgKMkgsoil−1). Furthermore, oxidative stress (induction of SOD, CAT and GST) and lipid peroxidation (increase in MDA) were also observed. In addition, there was a decrease in total available energy after exposure to PYR and KM. Exposure to fungicides resulted in a shift in the proportions of carbohydrates, lipids, and proteins affecting the amount of available energy. In addition to the initial findings on the effects of strobilurin formulations on enchytraeids, the observed results suggest that multiple and long-term exposure to strobilurin formulations in the field could have negative consequences on enchytraeid populations. [ABSTRACT FROM AUTHOR]

Numerous applications of silver nanoparticles (AgNPs), as well as the toxic effects of these particles on soil organisms and microorganisms, raise the question of how reasonable the entry of these nanoparticles into the environment is. Studying the behavior of these nanoparticles with soil organisms and also their effect on soil microorganisms may be the first step to finding out the answer. Structural and form differences in these nanoparticles for use in different conditions can change their behavior. The surface of these nanoparticles is covered with diverse coatings with differing surface charges affecting their fate in soil environments. Naturally, studying this aspect is essential to better understand how these particles impact the environment. In the present study, urease and dehydrogenase enzymes were used as soil health indicators to evaluate the effect of AgNPs and silver nitrate (AgNO3). In order to investigate the effect of surface charge, concentration, and exposure time, three concentration levels (5, 25, 125 mg/kg soil), three different types of charged coatings (citrate (Cit), polyvinylpyrrolidone (PVP) and polyethyleneimine (PEI)) were added to the soil as a treatment and the activities of dehydrogenase (as an indicator of overall microbial activity) and urease (indicator of nitrogen cycle) were measured at three times (1 h, 1 day and 90 days) after soil contamination. The results showed that with increasing the concentration of AgNO3 and AgNPs, the amount of dehydrogenase and urease activity decreased significantly. In the case of urease enzyme, nanoparticles with PEI coating (positive charge) had the greatest effect on reducing activity. In the case of dehydrogenase the opposite was true, and nanoparticles with Cit coating (negative charged) showed a greater inhibitory effect. With increasing incubation time, the amount of enzymatic activity of both types of enzymes showed less decrease, so that the greatest decrease in activity was in the first hour, then in the first day, and finally in 90 days. By comparing silver nitrate and nanoparticles it was found that the effect of AgNPs on enzymatic activity was greater than silver nitrate. [ABSTRACT FROM AUTHOR]

The coexistence of pesticides and plastic film residues in agricultural soils poses a significant threat to soil organisms due to their potential long-term contamination and combined toxic effects. Specifically, earthworms are at risk of simultaneously ingesting residual pesticides and microplastics, yet the impact of this combined exposure on their intestinal health and function remains poorly understood. In this study, earthworm (Eisenia fetida) were single and combined exposed to three particle sizes (10 μm, 500 μm, and 2 mm) of polyethylene microplastics (PE MPs) and imidacloprid (IMI) for 28 days, respectively. Our findings underscore that compared to single exposures, the combined exposure inflicted more profound injuries on intestinal tissues and elicited a heightened activation of intestinal digestive enzymes. Furthermore, the combined exposure significantly perturbed the relative abundance of several pivotal metabolic-associated gut microbiota, fostering an enrichment of pathogenic species. Metabolomics analysis showed combined exposure increased differential metabolites, disrupting amino acid, fatty acid, and carbohydrate metabolism in earthworm intestines, potentially hindering nutrient absorption and causing toxic metabolite accumulation. An integrated omics analysis implies that combined exposures have the potential to disrupt the relative abundance of crucial gut microbiota in earthworms, thereby altering their intestinal metabolism and subsequently impacting intestinal health and functionality. Overall, the results reveal that combined exposure of IMI and PE MPs exacerbate the negative effects on earthworm gut health, and this study holds significant implications for the holistic understanding of the combined toxic effects of microplastics and pesticide on soil ecosystems. [Display omitted] • Microplastics and imidacloprid co-exposure exacerbate negative effects on earthworm gut health. • Co-exposure significantly altered gut bacterial communities, increasing pathogenic species. • Co-exposure interfered with the amino acids, fatty acids and carbohydrates metabolic pathways. • The disruption of intestinal microbia and metabolites might be the mechanism of intestinal damage. [ABSTRACT FROM AUTHOR]

This study aimed to establish ecotoxicologically acceptable Cu concentrations for soil-residing species by integrating the biotic ligand model and the species sensitivity distribution. Statistical analyses were performed on 35 soil solution samples collected from four distinct land use sites: residential, agricultural, forested, and industrial regions. The environmental parameters of these samples, including pH, dissolved organic carbon (DOC), Ca2⁺, Mg2⁺, K⁺, and Na⁺ concentrations, exhibited wide variations across the four regions. Specifically, pH and the concentrations of Mg2⁺, K⁺, and Na⁺ showed significant variability. Additionally, a strong correlation was observed between pH and Ca2⁺, as well as between the DOC concentration and Mg2⁺ and Na⁺. Using the biotic ligand model, we derived the half-maximal effective activities of Cu (EC 50 {Cu 2+ }) for 10 soil organisms based on the chemical compositions of the soil solution samples. Additionally, a species sensitivity distribution approach was employed to determine the 5% hazardous concentration (HC5) for soil biota, which was closely associated with DOC and Na⁺ concentrations, with Mg2⁺ playing a secondary role. We attributed these relationships to the formation of DOC complexes that mitigate Cu toxicity, along with competitive interactions with cations. Notably, HC5 values did not differ significantly across sampling sites (p = 0.523). Clustering based on environmental factors grouped the samples into four clusters, each containing soils from different land use types. However, the third cluster included an outlier from agricultural soil due to its unusually high pH and DOC levels. These findings suggest that it is crucial to consider site-specific soil characteristics when determining ecotoxicologically acceptable Cu concentrations, and soil solution characteristics do not always align with specific land use patterns. [Display omitted] • Biotic ligand model and species sensitivity distribution were integrated. • From 35 soil samples, ecotoxicologically acceptable Cu concentrations were derived. • Soil solution characteristics do not consistently align with specific land uses. • Site-specific soil solution characteristics are good indicators of bioavailability. [ABSTRACT FROM AUTHOR]

The editorial in the Annals of Applied Biology introduces the new strapline "Biosciences for Sustainability" to better represent the journal's aims and scope. The journal, owned by the Association of Applied Biologists (AAB), focuses on high-quality research in various subject areas related to applied biology. The AAB aims to ensure that the content of Annals reflects the diverse interests of its members and activities, with a broad focus on advances in plant biology and agricultural production. Additionally, the journal maintains high statistical rigor in reviewing articles and plans to collaborate closely with the AAB through special issues and guest-editing opportunities for early career scientists. [Extracted from the article]

There is growing interest in interactions of microplastics (MPs) with other pollutants. However, there is limited understanding of the combined effects of MPs and silver nanoparticles (AgNPs) on nontarget soil organisms. This work aimed to examine the effects of exposure to various AgNPs' concentrations alone (0, 0.1, 1, 10, 100, 1000 mg kg−1, 50 nm) and in combination with polyvinyl chloride microplastics (PVC MPs, 80−250 μm) at 0.1% concentration for 28 days on reproduction, Ag accumulation, C/N ratio, and isotopic fractionation of the standard soil fauna collembolan Folsomia candida. Results showed that compared to the AgNPs exposure alone, the presence of MPs significantly reduced reproduction by 51.4% and markedly increased Ag content in collembolans by 87.7% at 1000 mg kg−1 AgNPs, which evidenced a synergistic effect. Co-exposure to MPs and AgNPs resulted in a noticeable reduction in the C/N ratio in F. candida body tissues by 9.90% and 5.27% at 1 and 10 mg kg−1 AgNPs, respectively, showing additive and synergistic effects. Additionally, this co-exposure altered stable isotope fractionation, with the highest increments of δ15N by 32.3% and inhibition of δ13C by 2.62%, demonstrating the turnover of nutrients shift in the collembolan tissues. Collectively, this study demonstrates that con-current exposure to environmentally relevant concentration of MPs and relatively high doses of AgNPs synergistically induces toxic effects on F. candida , leading to Ag accumulation and reproduction decline. These findings imply that MPs could alter collembolans' responses to AgNPs exposure, potentially enhancing the metal ions' bioavailability in soil environments and posing ecotoxicological threats to soil-dwelling organisms. [Display omitted] • Co-exposure to MPs and AgNPs reduces the reproduction of collembolan. • The presence of MPs enhances the accumulation of Ag in collembolan. • Co-existence of MPs and AgNPs introduces reduction in collembolan' C/N ratio. • Co-occurrence of MPs and AgNPs tends to increase δ15N and decrease δ13C. [ABSTRACT FROM AUTHOR]

This study investigates the effects of food waste biochar (FWB) on the biological properties of soil, including the microbial community structure, enzyme activities, lettuce growth, and earthworm ecotoxicity. This holistic assessment of various soil organisms was used to assess the potential of FWB as a soil amendment strategy. Pot experiments were carried out over a 28-d period using various FWB concentrations in soil (0–3% w/w). The presence of FWB enhanced the activity of alkaline phosphatase and beta-glucosidase in proportion to the FWB concentration. Similarly, the dehydrogenase activity after 28 d was positively correlated with the FWB concentration. Notably, the application of FWB improved the bacterial diversity in the soil, particularly among hydrocarbonoclastic bacteria, while also prompting a shift in the fungal community structure at the class level. Measures of lettuce growth, including total fresh weight, shoot length, and leaf number, also generally improved with the addition of FWB, particularly at higher concentrations. Importantly, FWB did not adversely affect the survival or weight of earthworms. Collectively, these findings suggest that FWB can enhance soil microbial enzyme activity and support plant growth-promoting rhizobacteria, potentially leading to increased crop yields. This highlights the potential of FWB as an eco-friendly soil amendment strategy. [Display omitted] • Phosphatase and beta-glucosidase activities were enhanced with food waste biochar. • Food waste biochar (FWB) enriched plant growth-promoting rhizobacteria. • FWB enhanced shoot length and leaf characteristics of lettuce. • FWB did not show any significant effects on earthworms up to 3%. • The results showed the potential of FWB as a soil amendment. [ABSTRACT FROM AUTHOR]

The increased production and expanding demand for cellulosic products have required companies to provide solutions for the proper disposal of generated residues without compromising soil quality. In this context, the current research aimed at evaluating the ecotoxicological impacts of dregs application in subtropical soils. The experiments were carried out with the earthworm Eisenia andrei , the springtail Folsomia candida , and the potworm Enchytraeus crypticus in two subtropical soils (Neosol and Cambisol) collected in the southern region of Brazil. The considerable differences in texture and organic matter content motivated the choosing of these soils. The reproductive rate of all organisms was influenced, with varying EC 50 values depending on the soil type. However, more pronounced effects were observed for Neosol. The springtail F. candida proved to be the most sensitive to contamination (EC 50 = 5.8 g kg−1 for Neosol and 48.5 g kg−1 for Cambisol), followed by the earthworm E. andrei (EC 50 = 62.4 g kg−1 for Neosol and 129.5 g kg−1 for Cambisol) and the potworm E. crypticus (EC 50 = 67.2 g kg−1 for Neosol and 230.4 g kg−1 for Cambisol). As a result, while dregs can be used to correct soil acidity, they have been shown to have negative effects on important organisms responsible for functions critical to maintaining ecosystem quality. [Display omitted] • Dregs are a by-product from the pulp and paper industry that is suggest to be a soil pH corrective. • Soil organisms are vital to the maintenance of the soil health. • Dregs are capable of affect the reproduction rates of soils organisms. • The toxicity of dregs varies according to the soil chemical characteristics. • Metal levels in the dregs matrix are less of concern than the increases in Na content. [ABSTRACT FROM AUTHOR]

The neonicotinoid acetamiprid is used as a foliar insecticide spray, which results in direct exposure of a wide variety of soil organisms. Laboratory testing indicated that acetamiprid is toxic to the Collembola (springtails) species Folsomia candida , while Acari (mites) seem relatively insensitive to neonicotinoids. Since such opposing effects on different soil arthropods might imbalance natural arthropod communities, this study determined: (i) if field-realistic doses of acetamiprid affect the abundance and diversity in soil arthropod communities, and (ii) whether these potential effects are short-term or persist after degradation of acetamiprid. Intact soil cores collected from an untreated grassland field were placed in the mesocosm set up 'CLIMECS', and the naturally sourced communities were exposed to a control and increasing field-realistic doses of acetamiprid (i.e. 0, 0.05, 0.2, 0.8 mg a.s./kg dry soil). Before and 7 and 54 days after spraying the insecticide, the abundance of mites and springtails and springtail diversity were assessed. Springtail and mite abundances were similar at the start of the experiment, but springtail abundance was significantly lowered while mite abundance increased shortly after exposure to increasing doses of acetamiprid. At the highest dose, springtail numbers decreased by 53% on average while the number of mites increased by 26%. This effect was no longer visible after 54 days, suggesting recovery of the community as a whole reflected by observed changes in community dissimilarity: shortly after application springtail communities clearly diverged from the control in terms of species composition, while communities converged again in the long-term. With our results, we are the first to show that field-realistic applications of N-nitroguanidine neonicotinoids can significantly impact natural soil fauna communities, which might have implications for soil ecosystem functioning. [Display omitted] • Mesocosm study with indigenous soil community dosed with acetamiprid. • Effects assessed after 7 and 56 days after acetamiprid spraying. • Dose-related decrease in Collembola and increased mites at day 7. • Collembola numbers indifferent from the control after 56 days. • Soil arthropod community affected at field realistic acetamiprid dose. [ABSTRACT FROM AUTHOR]

Metal pollutants have become increasingly diverse. Therefore, managing the ecological risks associated with these elements in soil is urgently required. However, determining the soil ecological risk thresholds of elements through routine toxicological tests is time-consuming and laborious, establishing prediction models is vital to risk management. Accordingly, this study aimed to predict the element toxicity to soil organisms by collecting the toxicological data of eight elements to soil organisms at 18 European and 17 Chinese sites through literature and toxicology databases, using the quantitative ion character-activity relationship (s-QICAR) model. Firstly, the toxicity values (logEC 10) of eight elements to five biological species and three microbial processes were obtained through clustering and soil normalization methods in three typical soil scenarios. Correlation analysis revealed that for different species and microbial processes, there are three to six physicochemical properties of elements related to their toxicity, among which, the covalent radius of the element was the best significantly correlated with logEC 10 of all organisms (R2 = 0.77–0.95). Based on this, the s-QICAR model was established and used to predict the logEC 10 of Sc, Ti, V, Cr, Co, Ni, Cu, and Zn to eight organisms. Furthermore, along with the species sensitivity distribution curve, the HC 5 values (i.e., 95% species protection level) for the above eight elements were calculated. Following correction, the predicted no-effect concentrations of these elements ranging from 9 to 189 mg/kg, and the ecological risk threshold map has been produced. In summary, we present a new method to quantify the ecological risk of metal-induced pollution in European soils without routine toxic measurements, and provide important insights into soil pollution risk assessment and management. [Display omitted] • Soil normalization models were established using 609 toxicity data values. • S–QICAR was used to predict lacking values for elements toxicity in soils. • Ecological risk thresholds of metal elements in the fourth cycle were derived. • Eight ecological risk distribution maps for elements in Europe were produced. [ABSTRACT FROM AUTHOR]

• Gravel content has a non-linear effect on the precompression stress of forest soil. • Volume shrinkage occurs in forest soil after several freeze–thaw cycles. • The compression index of forest soil is related to soil organic carbon content. Due to climate change, human activities and natural disturbances in high-latitude permafrost and seasonally frozen areas are gradually increasing, attracting more attention from scholars. However, research primarily focuses on soil biology and chemistry in these regions, with limited exploration of their mechanical properties, especially compression properties. This study aims to evaluate the effects of gravel content and freeze–thaw (F-T) cycles on the compression properties of coarse-grained layered forest soil from northeast China's seasonally frozen regions, with the goal of predicting the soil's compressive changes under heavy mechanical loads. Specifically, using uniaxial confined compression tests (UCCT) on 252 disturbed soil samples (including two soil layers: AB and B hs ; six gravel contents; and seven F-T cycles), three characteristic compression coefficients—precompression stress (σ pc), compression index (C c), and swelling index (C s)—were measured. Additionally, scanning electron microscopy (SEM) was used to analyze the mesostructure evolution of coarse-grained gravel-bearing soil. Volume changes of samples were measured after 15F-T cycles with varying gravel contents. Results indicate non-linear effects of gravel content and F-T cycles on σ pc. Gravel content below 50% positively influences σ pc , while content above 50% increases soil pore content, decreasing σ pc. C c and C s exhibit an approximately negative correlation with gravel content and initially increase followed by a decrease with more F-T cycles. Moreover, the σ pc and C c of the AB layer are higher than those in the B hs layer, likely due to differences in clay and organic carbon contents. Notably, the observed trends differ from previous studies on other soil types such as farmland and paddy fields. This study fills a gap in understanding the compression characteristics of layered gravel-bearing forest soil in seasonally frozen regions, providing valuable insights for evaluating soil compression in both seasonally frozen and permafrost regions, and understanding mechanical vehicle-soil interactions. It also lays the theoretical groundwork and provides data support for constructing compression models of layered gravel-bearing forest soil. [ABSTRACT FROM AUTHOR]

[Display omitted] • OC, CEC, and AK were selected as the minimum dataset for constructing the SQI. • SQI-SES relationships varied spatially, showing both positive and negative correlations. • Four distinct zones were clustered based on the SQI-SES relationships. • Impacts of 11 social-ecological factors on zones were identified to guide policy-making. Urban expansion has profound impacts on soil quality in peri -urban areas. Understanding the intricate spatial relationship between soil quality index (SQI) and soil ecosystem services (SESs) in response to social-ecological factors is crucial for achieving sustainable soil utilization and management. In this study, a total of 485 soil samples were collected from different land-use types (including paddy field, dry land, orchard, and forest) in peri -urban areas of a city (Nanchang) in central China. The assessments of soil quality based on SQI and SESs were conducted using multi-source heterogeneous data. We determined the spatial relationships between SQI and six SESs using bivariate spatial autocorrelation analysis, and deciphered the role of 11 social-ecological factors in driving SQI–SES relationships across different zones. The results showed that SQI and SESs exhibited significant spatial clustering (P <0.01), despite certain variations in their distribution patterns. SQI had significant positive spatial correlations with soil organism habitat, food provision, erosion control, carbon storage, and filtering and buffering (r = 0.16–0.48, P <0.05). Two-step clustering categorized 183 villages with distinct SQI–SES relationships into four zones, i.e., soil ecological protection zone, food production core zone, soil quality enhancement zone, and soil ecological restoration zone. The impacts of various social-ecological factors on different zones were unveiled and corresponding development recommendations were presented. Results of this study facilitate the formulation of peri -urban-specific soil conservation policies and management strategies. Our work provides guidance on the improvement of soil quality and soil ecosystems, contributing to the future achievement of sustainable development goals. [ABSTRACT FROM AUTHOR]

Crop diversification tends to favor the soil fauna community, soil aggregation, and consequently soil organic carbon (SOC) stock. Understanding the association between these attributes can help in understanding the dynamics of physical protection of soil organic matter. In this context, our study aimed to answer: (1) how does the edaphic macrofauna community and soil carbon and aggregate classes respond to two types of coffee agroforestry systems (coffee with Grevillea robusta and coffee with banana) and how these responses differ from native ecosystem; (2) how and to what extent are soil aggregation regulated by the complex structural interactions of plant residue input, SOC, and the soil faunal community? The work was conducted in the municipality of Planalto, state of Bahia, Brazil. Three systems were evaluated: agroforestry system of Coffee arabica L. with Grevillea robusta (CG); agroforestry system of Coffee arabica with Musa spp. (CB); and native forest (NF). Four plots were delimited in each system, in which dry fractionation of the soil was performed to obtain aggregates of classes >6, 6–4, 4–2 and < 2 mm. The macrofauna was sampled using the Tropical Soil Biology and Fertility Program method. The labile and total carbon of the soil and aggregates were determined and the carbon management indices were calculated. The CG and CB presented a greater amount of larger size aggregates (> 6, 6–4 and 4–2 mm) than the NF. The CB system provided more favorable conditions for the soil macrofauna. Despite this, both coffee agroforestry systems favored the occurrence of Oligochaeta. The CG was more favorable to maintain labile fractions of organic matter than the CB. The edaphic fauna show a close relationship with the formation of carbon aggregates and stabilization which was directly influenced by continuous input of plant residues in diverse coffee growing systems. [Display omitted] • The banana coffee system provides favorable conditions for soil macrofauna, aggregation and carbon. • Coffee agroforestry systems (AFSc) favor the occurrence of earthworms and larger aggregates. • The presence of Grevillea robusta in AFSc increases the labile fraction of soil carbon. • The input of residues in AFSc positively influences aggregation and soil carbon stabilization. [ABSTRACT FROM AUTHOR]

Forest management strategies can effectively mitigate the impacts of drought on tree species, but their effects on soil fauna remain largely unexplored. Among soil organisms, soil nematodes can serve as valuable bioindicators to assess the impact of forest management on soil biodiversity and soil functioning. Consequently, we investigated two related questions in a Mediterranean Pinus halepensis Mill. forest located in southeastern France. First, how do soil nematodes respond to forest management practices? Second, can forest management practices help modulate the effects of Mediterranean summer drought on these soil organisms? We conducted a field experiment in which we explored the influence of two forest management techniques—tree thinning (intense, moderate, or absent) and understory removal (shrubs present or absent)—on soil nematodes before and after the summer drought. We found that only total and bacterivorous nematode abundances were positively influenced by the forest management practices. The highest values were observed under conditions of intense thinning combined with shrub presence, with an average of 97,509 individuals per kg of dry soil. In contrast, the abundances of all nematodes, with the exception of predaceous nematodes, were lower after the summer drought with a reduction ranging from −55 % to −82 %. Total, bacterivorous, and fungivorous nematode abundances were less negatively affected by the summer drought under conditions of moderate thinning when shrubs were present versus absent. More generally, we discovered that bacterivorous and fungivorous nematodes were particularly sensitive to the forest management practices and the summer drought. It is thus apparent that habitat alterations induced by forest management can strongly affect nematode community structure and could therefore prompt shifts in ecosystem functioning. Finally, this study highlights that, in forests, understory vegetation can have significant positive impacts on soil nematode populations when severe dry periods occur. [ABSTRACT FROM AUTHOR]

One of the intrinsic features of the soil is its function, which relates to the land cover and management. However, the effect of land use/cover changes and management systems on indicators of soil functionality, especially in semi-arid regions is less known. Hence, in the present study soil samples were collected from five typical land cover types in a semi-arid mountainous area of northern Iran: (1) a natural forest (Carpinus orientalis and Quercus macranthera), (2) rangeland (Crataegus melanocarpa and Crataegus microphylla - Berberis integerrima), (3) 30-year-old walnut orchard, (4) agriculture (Hordeum vulgare) with moldboard plowing, and (5) agriculture (Hordeum vulgare) with disk plowing. For each type of land cover, three 1-ha areas spaced 4–6 km apart were chosen in order to avert pseudo-replication. Both physical and biochemical soil properties were assessed at a depth of 0–10 cm from the four corners of the plots in August, comprising a total of 60 samples (5 land covers x 12 samples for each study site) Additionally, soil biological properties were determined in August and November, making a total of 120 samples. Our results showed that available soil nutrients in the forest site were 1.5–2.5 times higher than in the agricultural (disk) site. The highest and the lowest levels of enzymatic activities were found in the forest site and agricultural (disk) site, respectively. In the autumn season, the highest soil biota abundances, except for bacteria and fungi, were observed in the forest site. Also, the biomass of earthworms in the forest site was almost 80 % higher than in the agricultural site. Overall, land covers were classified based on the degree of effect on soil functional indicators as follows: forest > rangeland > orchard > agriculture (moldboard) > agriculture (disk). Taken together, our findings illustrate that preserving natural vegetation is essential for maintaining soil quality on a high level and contributing to the development of fertile areas in mountainous semi-arid ecosystems of northern Iran. The ground vegetation is a key factor affecting the soil functions, and any alteration in the land use, such as switching from forest to agriculture can have a detrimental effect on the quality and productivity of the soil in the long-term. [Display omitted] • Anthropogenic activity reduces soil fertility and biota population in semi-arid regions. • Soil organism density shows significant seasonal variation between summer and fall. • Soil microbial activity and enzymes had higher values under natural ecosystems. • Carpinus orientalis increases various aspects of soil ecosystem services. • Moldboard-managed agroecosystems show better soil functions than disk-plowed ones. [ABSTRACT FROM AUTHOR]

Generative AI (GenAI) is becoming a valuable tool for enhancing efficiency and can be used to help foster critical thinking skills among students and possibly assist in hypothesis generation. GenAI can excel at improving original content and to make it more accessible to broader audiences. While GenAI can create stunning images, inaccuracies persist, even with well-designed prompt engineering. Likewise, challenges persist in GenAI processing nuanced information accurately, highlighting the need for foundational knowledge and critical thinking when creating prompts and interpreting GenAI responses. • Generative AI can be a valuable tool, but it requires sufficient critical skills to prompt and interpret responses. • The SBB community may face a unique challenge because soil biology is not well represented in source material. • Developing prompting skills will be necessary to minimize inaccuracies. [ABSTRACT FROM AUTHOR]

Changing the hydrological behavior of soils contaminated with oil has an essential effect on soil erosion and runoff generation processes. However, the applied and economically efficient and environmentally friendly approaches to tackle the contamination-related soil and water loss issues have yet to be found. Therefore, adopting appropriate conservation measures in petroleum-contaminated soils through the application of environmentally friendly is crucial. Soil microorganisms play a critical role in ecosystem function by improving soil's physical and chemical properties. Nonetheless, the effectiveness of such microorganisms in controlling soil loss on petroleum-contaminated soils has to be studied. Hence, the present study has elucidated the effects of surface inoculation of endemic soil microorganisms on exceeded soil loss from petroleum-contaminated soil. Towards that, soil samples were collected from Iran's Tehran Oil Refinery suburban area. The soil was further contaminated by 720 mL of gasoil, which was evenly sprayed superficially. The suitable bacteria, cyanobacteria, and fungi effective in soil and water conservation and available in the soil organism's micro-bank were selected, purified, propagated, and inoculated uniformly on the soil surface of small 0.25 m2-plots. The plots were then exposed to a simulated design rainfall with an intensity of 35 mm h−1 and 30 min duration placed on a slope of 25%. The performance comparison of solo bacteria, cyanobacteria, fungi, and consortium bacteria + fungi, bacteria + cyanobacteria, cyanobacteria + fungi, and bacteria + cyanobacteria + fungi inoculation on the soil contaminated with gasoil verified non-significant (p = 0.40) changes +0.44%, −81.26%, −87.56%, −39.25%, −92.98%, −96.09%, and −39.70% in soil loss They further caused non-significant (p = 0.47) increases of 26.65%, 56.32%, 74.53%, 27.33%, 78.94%, 87.66% and 62.01% in sediment concentration compared to those reported for the control treatment (i.e., uncontaminated soil and with initial level of contamination). The approach with further emphasis on the application of individual or combined use of cyanobacteria and fungi can be supposed to be a bio-strategy, sustainable, environmentally-friendly, and efficient technique for petroleum-contaminated soil conservation thanks to the ability of soil microorganisms in improving soil physical and chemical properties. [Display omitted] • Microorganisms' effects on soil loss from petroleum-polluted soil were studied. • Microorganisms mitigated soil erosion attributes in a gasoil-polluted soil. • Microorganisms' inoculation improved soil properties in gasoil-polluted soil. • Results help soil and water conservation in at-risk petroleum-contamination areas. [ABSTRACT FROM AUTHOR]

The current use of chemicals puts pressure on human and ecological health. Based on the Aarhus Convention, citizens have the right to have access to information on substances in their local environment. Providing this information is a major challenge, especially considering complex mixtures, as the current substance-by-substance risk assessment may not adequately address the risk of co-exposure to multiple substances. Here, we provide an overview of the currently available indicators in the Netherlands to explore current scientific possibilities to indicate the impacts of complex chemical mixtures in the environment on human health and ecology at the local scale. This is limited to impact estimates on freshwater species for 701 substances, impact estimates of four metals on soil organisms, and impacts on human health for particulate matter (PM 10) and nitrogen dioxide (NO 2) in air. The main limiting factors in developing and expanding these indicators to cover more compartments and substances are the availability of emission and concentration data of substances and dose-response relationships at the population (human health) or community (ecology) level. As ways forward, we propose; 1) developing cumulative assessment groups (CAGs) for substances on the European Pollutant Transfer and Release Register and Water Framework Directive substance lists, to enable the development of mixture indicators based on mixture risk assessment and concentration addition principles; 2) to gain insight into local mixtures by also applying these CAGs to emission data, which is available for soil and air for more substances than concentrations data; 3) the application of analytical non-target screening methods as well as effect-based methods for whole-mixture assessment. • We provide an overview of environmental indicators on substances in the Netherlands. • Chemical mixtures are insufficiently addressed in environmental indicators. • Determining the impact of mixtures is difficult due to data insufficiencies. • Cumulative assessment groups should be developed for environmental substances. • Local emission data and whole-mixture methods could be better utilized. [ABSTRACT FROM AUTHOR]

Anthropogenic activities such as long-term fertilizer application are known to lead to losses in above and belowground biodiversity, thereby negatively impacting ecosystem function. However, our understanding of the relative sensitivity of different soil organisms groups to increasing fertilizer application levels remains largely unknown. To address this knowledge gap, we investigated the impacts of different long-term fertilization regimes, and the associated changes in plant communities, on a broad range of soil organisms, including bacteria, fungi, protists, and nematodes, in the alpine meadow ecosystem of the Qinghai-Xizang Plateau. Results showed that the community composition of protists was the most sensitive to different fertilization regimes as compared to those of bacteria, fungi, and nematodes. Changes in the protist community were also most strongly linked to changes in plant richness and biomass under prolonged fertilization. Nitrogen fertilizer addition leads to more deterministic community assembly processes for protist communities, while phosphorus fertilizer application leads to more stochastic assembly processes. Together, our results suggest that protists may be among the most susceptible soil organisms concerning the impact of human disturbances like fertilizer application, highlighting their potential importance as sensitive ecological indicators of human-induced disturbances in terrestrial ecosystems. • Protists was more sensitive to fertilization regimes compared to bacteria, fungi and nematode. • Protists were highly linked to changes in plant richness and biomass. • Nitrogen fertilizer addition led to deterministic processes in protist community assembly. • Phosphorus fertilizer application led to more stochastic assembly processes in protist community assembly. [ABSTRACT FROM AUTHOR]

• Fertilization significantly affected bacterial community structure and body size. • Fertilization did not affect fungal community diversity and body size. • The body size of soil nematode communities was very sensitive to fertilization. • In total, the body size of soil organisms was sensitive to environmental changes. The effective use of soil biological resources requires a thorough understanding of the ecological roles played by biological communities. The majority of research on soil biological communities has concentrated on their structural aspects, such as diversity and composition. However, further efforts are required to provide a comprehensive understanding of community characteristics. Body size can be used to better understand the ecological activities of soil biological communities, as it is a significant life history feature of organisms. The current study examined alterations to the populations of bacteria, fungi, and nematodes in soil samples that were treated with chemical fertilizer (CF), organic fertilizer (OF), or no fertilizer (CK). The results showed that, in comparison to CK, OF treatments reduced the Shannon diversity of the bacterial community. The fertilization treatments (CF and OF) resulted in a significant increase in the community-weighted mean (CWM) of bacterial body size and the relative abundance of Candidatus koribacter , as compared to the CK treatment. The body size and diversity of the fungal did not significantly differ across the fertilization treatments. Additionally, the CF treatment led to a higher relative abundance of Mortierella in the soil when compared to the CK and OF treatments. The CWM of nematode body size varied dramatically across treatments, whereas there was no discernible variation in diversity or composition. Furthermore, a comprehensive analysis has been carried out utilizing three separate approaches to assess the sensitivity of the soil biological community diversity, composition, and body size to environmental changes. These methods include correlation heatmap, redundancy analysis, and structural equation model. The study consistently showed that the CWM body size of soil organisms is more vulnerable to environmental changes compared to the variety and composition of the community structure. Meanwhile, the current study has revealed that this tendency is less prominent in fungal communities and more apparent in nematode colonies. Our results highlight the importance of body size in characterizing the dynamics of soil biological communities. Our findings imply that when examining the ecological roles of soil biological communities, variations in body size should be taken into account. [ABSTRACT FROM AUTHOR]

The widespread application of neonicotinoid insecticides (NNIs) has attracted widespread attention to their potential ecotoxicological effects. In this study, we systematically evaluated the toxic effects of thiamethoxam (TMX) and its metabolite clothianidin (CLO) on earthworms (Eisenia fetida). Specifically, the antioxidant system responses and endogenous metabolite metabolism responses in earthworms were analyzed in the temporal dimension after 7, 14, 21 and 28 days of exposure to TMX and CLO. The results found that TMX and CLO could inhibit the growth phenotype of earthworms and cause significant changes in antioxidant system related indicators. More importantly, we found that TMX and CLO could cause significant changes in the metabolic profiles of earthworms through NMR-based metabolomics. From the changes in endogenous metabolites, the toxicity effects of TMX on earthworms gradually increases with prolonged exposure time. Differently, the toxicity effects of CLO on earthworms is significantly higher than that of TMX in the early stages of exposure. Meanwhile, these impacts will not weaken with prolonged exposure time. Furthermore, the results of KEGG enrichment pathway analysis indicated that TMX and CLO could significantly interfere with energy homeostasis, redox homeostasis, osmotic regulation, amino acid metabolism and protein synthesis in earthworms. These findings further deepen our understanding of the ecotoxicological effects of NNIs on soil organism. [Display omitted] • TMX and CLO could inhibit growth and interfere with antioxidant systems in earthworms. • TMX and CLO could cause disturbances in the metabolic profiles of earthworms. • The adverse effects of TMX on earthworms increase with prolonged exposure time. • Short term exposure to CLO had stronger toxicity effects on earthworms than TMX. [ABSTRACT FROM AUTHOR]

Olive is one of the largest crops in Spain, primarily for oil extraction from drupes. This process produces a by-product called 'alperujo', which can be composted and used as fertilizer. This study investigated the impact of 'alperujo' compost on ground/soil invertebrate inhabitants compared to mineral fertilization in two groves with different crop management types (superintensive and traditional) during 2021 and 2022. Anystidae/Erythraeidae (Acari; Trombidiformes) and Acari (Other) were more abundant in the compost treatment in both groves, but significant only in the superintensive grove. Some other ground/soil inhabitants, such as Anthicidae (Coleoptera), Araneae, and Gastropoda were generally more present in the compost treatment of the superintensive grove. No significant effect of fertiliser treatment was observed for other ground/soil organisms. Future studies with more replicas and over a longer period of time should be performed to confirm these results, but they can be considered of interest to push forward the implementation of 'alperujo' compost in the olive fertilization, favouring a circular economy and a sustainable agriculture. [ABSTRACT FROM AUTHOR]

Earthworms and enchytraeids are soil organisms involved in key soil functions, such as organic matter turnover and soil structure, at different scales. In natural soils, these organisms are exposed and sensitive to different abiotic factors (e.g., climate, land use and management) and are often used as bioindicators of human disturbances, particularly chemical stress. However, the sensitivity of these two groups of Oligochaeta (Annelida) to different stressors has never been compared. Using data from 49 publications and 330 observations, we performed a meta-analysis to compare the sensitivities of earthworms and enchytraeids to all kinds of stressors under similar test conditions. Earthworms and enchytraeids were found to be equally sensitive to chemical stressors (mean effect size −0.61 [-2.53; 1.30]) regardless of the studied endpoint (mortality or reproduction). Most of the observations dealt with the effects of pesticides (42 %) and heavy metals (40 %) on both organisms. No difference in sensitivity was revealed when these two stressors were considered separately. Regarding the two most studied species of enchytraeids and earthworms, the mean effect sizes of all the possible combinations of Eisenia fetida (41 % of the studies) or Eisenia andrei (48 %) or Enchytraeus crypticus (73 % of the studies) or Enchytraeus albidus (27 %) did not reveal any differences in sensitivity. This study also highlights the lack of studies on environmentally relevant (i.e., representative of natural soils) enchytraeid and earthworm species. We also revealed that mostly ecotoxicologists have compared the sensitivities of these two key soil organisms when they are exposed to and threatened by other important factors, such as agricultural practices and climate change. • Enchytraeids and earthworms were similarly sensitive to stressors (chemicals; heavy metals; wates, by-product; other). • Results are the same whatever the studied stressors, species, and endpoints. • 99 % of the studies comparing their sensitivity deal with contaminants. • Studies on soil organism sensitivity under realistic natural conditions are lacking. [ABSTRACT FROM AUTHOR]

Earthworms are key organisms of soil ecosystems, however, the determinants of the structure and distribution of earthworm communities and their relationships with agricultural practices are not well-studied in Canada. We sampled earthworm communities from four different habitat types along a disturbance gradient: agricultural crop land, forest around crop fields (buffers), recently restored natural grassland, and forests from conservation areas. As most species living in Canada are considered exotic and because of the recent colonization of Canadian soils by mostly European species after the extinction of the native species due to the glaciation of North America during the Pleistocene, we hypothesized that the impact of agricultural practices will be similar to what is observed in Europe: for example, crop habitat showing lowest abundance, richness, and proportion of epigeic and anecic species, due to lesser soil organic matter content and higher soil disturbance. We also hypothesized that important soil variables would be associated with these habitat differences. For each habitat we sampled earthworms using a combination of two methods (quantitative + qualitative) at three replicate sites, for two years between May and July together with important environmental variables. We found lower density and diversity of earthworms in crop habitat and proportionally more epigeic species than expected. Contrary to our predictions, forest-buffer earthworm communities were more similar to crop than to forest habitats, and soil environmental variables could not explain the variations in the spatial distribution of earthworm communities. In fact, our results revealed a more homogeneous distribution of the species diversity across the habitat gradient at local scales in Southern Ontario. This was mainly associated with spatial factors, probably due to historical extinction-colonization events of earthworms in Canada and the high invasive potential of the species currently present. [ABSTRACT FROM AUTHOR]

Earthworm species interact with each other in soils, but these interactions are poorly understood. Moreover, these key soil organisms are influenced by abiotic soil components such as organic matter. Here, we investigated the influence of Allolobophora chlorotica and Aporrectodea nocturna , two earthworm species from different ecological categories, on the incorporation of organic matter, reproduction and weight change of the endogeic Aporrectodea caliginosa. Two different types of organic matter i) a compost and ii) a fresh refined organic material, both from green waste, were used. Earthworm parameters were monitored during an 8-weeks laboratory experiment using a vineyard soil in order to identify positive and negative interactions between species. Irrespective of species, earthworms interacted preferentially with smaller particles, more decomposed and with a lower C/N ratio. For an equivalent earthworm biomass, similar amount of green compost was incorporated by A. caliginosa and A. nocturna. However, A. chlorotica did not bury this material. The green compost increased the reproduction rate of A. caliginosa when associated to A. chlorotica. Moreover, the association with the epi-anecic A. nocturna increased the reproduction rate of A. caliginosa with the addition of refined organic matter (fresh material). Furthermore, in both earthworm associations, the weight loss of A. caliginosa was reduced by the addition of green compost to the soil surface. These results highlight the importance of earthworm interactions in maintaining populations, and emphasized the need of field studies to confirm these interactions, particularly in the context of soil fertility where organic amendments are often applied. • A. nocturna increases A. caliginosa reproduction rate with fresh organic matter. • Green compost improves earthworm body mass and reproduction rate compared to control. • Earthworms incorporate more easily fine organic particles with low C/N ratio. • A. caliginosa incorporates green compost similarly to A. nocturna. [ABSTRACT FROM AUTHOR]

The impact of microplastics (MPs) on soil organisms is still a growing field, yet very little is known about the exposure of ultraviolet (UV) aging of MPs to soil organisms. In this study, we explored the response of the epigeic earthworm Eisenia andrei to pristine and UV-aged polyethylene (PE-MP) exposure at a wide range of environmentally relevant concentrations (0, 0.2, 2, 20, 200 and 2000 mg kg−1) in an organic farm soil for 56d and assessed changes in reproduction, ingestion, egestion and gut microbiome. Results showed that exposure to 20 mg kg−1 pristine PE-MP significantly increased earthworm reproduction by 39 % but the same concentration decreased reproduction by 29 % when they were exposed to UV-aged PE-MP. Ingestion of PE was verified by staining the whole worm body and their casts after 48h of starvation. The amounts of PE-MP found in the body and the casts were positively correlated with PE-MP concentrations in the soil, however only significantly so with pristine PE-MP. A decline in E. andrei gut microbiome alpha diversity and a significantly different community composition were observed in UV-aged PE-MP exposures compared to pristine PE-MP. Relative to the control treatments, Proteobacteria increased up to 135 %, Actinobacteria increased up to 35 %, and Firmicutes decreased up to 38 % under UV-aged PE-MP exposure, whereas Cyanobacteria increased up to 19 times in the pristine PE-MP treatments. These results confirm the negative effect of UV-aged PE-MP on earthworms even at low concentrations and could have important implications in the well-functioning of agricultural soils. [ABSTRACT FROM AUTHOR]

Studies on interactions between plants and belowground organisms, or between plants and aboveground organisms, are numerous and highlight their importance in understanding ecosystem functioning. However, these two compartments are rarely studied together, despite the direct link formed by the plant itself. Soil organisms can influence interactions between plants and herbivores by changes in plant growth and chemistry. Under controlled conditions the influence of earthworms and aphids on wheat was investigated. The effect of earthworms on aphid reproduction was also investigated, to demonstrate the indirect plant-trait-mediated effects. We showed a significant effect of both above and belowground organisms on wheat. Interestingly, nitrogen content was higher in the presence of aphids (1.63 ± 0.07 %,) or earthworms alone (1.58 ± 0.04 %) and even higher in presence of both (2.07 ± 0.07 %). Moreover, we showed a strong effect of earthworms on aphid reproduction rates which are almost twice as high as in the absence of earthworms where we observed a reproduction rate of 32 individuals per day compared with 57 in the presence of earthworms. The presence of aphids led to a 16 % reduction in above-ground biomass compared with the control (1.83 ± 0.08 g vs 2.19 ± 0.09 g for the control), while the presence of earthworms led to an 46 % increase (3.20 ± 0.12 g vs 2.19 ± 0.09 g), and the presence of both organisms had no significant effect on the above-ground biomass of wheat compared with the control (2.39 ± 0.08 g vs 2.19 ± 0.09 g). These results could have implications for pest management, as they indicate that the presence of earthworms compensate the negative effect of aphids on plant biomass, probably by acting on nutrient uptake and plant defensive traits. By addressing the effects of earthworms on both the pest performances and plant traits, we highlight the need for further research on the indirect effects of below-ground compartments on pest performance. This study builds towards a better understanding of the interaction between soil, plant and pests and highlights the importance to study the pest management with a holistic view of agroecosystems. • Pest management must include a global vision of agroecosystem functioning. • Soil biota influence plant-pest interactions by changes in plant growth and chemistry. • Earthworms promote aphid reproduction and plant growth by promoting resource acquisition. • Earthworms compensate for the negative effect of aphids on wheat biomass. • It is crucial to study pest management with a holistic view of agroecosystems. [ABSTRACT FROM AUTHOR]

Fertility islands are patches of soil beneath the trees and shrub's canopy and contain higher nutrient availability and water content than the surrounding areas in arid and semi-arid lands. Fertility islands are home to various soil organisms that play a crucial role in nutrient cycling. This study aimed to determine the influence of fertility islands beneath the coppiced oak trees on soil macrofauna diversity and biomass in semi-arid oak woodland. For this purpose, two main microhabitats, including beneath the patches of oak sprout-clumps (BPSC) and the interspaces (SBSC), were considered. Each microhabitat was divided into four classes with respect to the number of sprouts per sprout-clumps (N = 1–3, N = 3–10, N = 10–20, and N > 20) and distance gradient from the canopy (D = 0 m, D = 1–3 m, D = 3–5 m, and D > 5 m). Soil physical and chemical properties, soil macrofauna taxonomic group diversity, and biomass were measured for each microhabitat class. Most of the soil's physical and chemical properties, such as soil litter, soil organic carbon (SOC), available phosphorus (P), moisture content, and electrical conductivity (EC), were higher in BPSC than in SBSC. These properties were influenced by the structure (number of sprouts) of oak sprout-clumps and the distance gradient from the canopy. Soil macrofauna individuals (density), biomass, and diversity were higher in BPSC than in SBSC. A significant difference in soil macrofauna groups composition was found only at the canopy edge and was not affected by increasing distance from the canopy. The soil macrofauna diversity was positively correlated with soil moisture, SOC, and P. It was concluded that the sprout-clumps' structure influences the quality of fertility islands beneath the oak sprout-clumps and consequently dictates the variation of soil macrofauna composition and biomass. • The structure of oak sprout-clumps controls fertility islands quality. • Increasing the spaces between the sprout-clumps magnify fertility islands effect. • The quality of fertility islands influences soil macrofauna diversity. • Gradient distances between the tree canopies influence soil macrofauna biomass. [ABSTRACT FROM AUTHOR]

Microplastic pollution is a problem of global concern. This study is based on a laboratory experiment that was performed to investigate how soil-added microplastic particles (MP) affect soil microorganisms and mesofauna with a focus on enchytraeids (Annelida). In an experiment presented, polyethylene spherical MP of two sizes, 60 μm and 140 μm, (Cospheric LLC, USA) were applied (0.8 % w/w) to three different soils (mesocosms). The effect of MP was measured twice, 3 and 15 weeks after application as soil microbial activity (basal respiration rate), soil mesofauna feeding activity (bait-lamina test), and number and body length of enchytraeids (after wet funnel extraction). Both applied MP sizes caused a significant increase in soil respiration rate compared to controls (10 % on average). Mesofaunal feeding activity decreased in MP treated soils compared to controls (15 % on average), but the effect was significant only as an interaction between MP treatment and time. MP added to the soil did not affect the number of enchytraeids, nor their total body length or mean body length, but the body length distribution of enchytraeids differed between MP treatments and controls. These results may indicate that the effect of MP may differ between soil microorganisms and mesofauna. Changes in the body length distribution of enchytraeids, particularly a decrease in the smallest length class, may serve as a simple indicator of impending assemblage collapse. [Display omitted] • Microplastic particles in mesocosm study affect soil organisms differently in three soils. • MP increased the soil respiration rate but decreased the feeding activity of soil mesofauna. • MP caused a shift in the body length distribution of enchytraeids, with no effect on their mean number and total body length. [ABSTRACT FROM AUTHOR]

The growing resistance of weeds to herbicides demands innovative strategies that harness soil biology for effective weed control. We examined the use of carbon amendments to stimulate microbial immobilization of soil nitrogen for weed control. We hypothesized that increased carbon availability will stimulate soil microbial growth, leading to greater nitrogen immobilization, which consequently decreases plant-available nitrogen and suppresses the growth of nitrogen-responsive weed species. We buried 80 19-L pots in a research farm field and added sawdust and sucrose to soils as a high carbon treatment and used unamended soils as a control. We examined eight different weed species separately, and measured plant growth, soil carbon, available nitrate, microbial carbon and nitrogen, and microbial community composition after 11 weeks of treatment. The carbon amendments altered plant-microbial competition for nitrogen, resulting in reduced biomass for most weed species. The carbon-amended soils had higher microbial biomass carbon and nitrogen, slower nitrogen cycling, and less available soil nitrogen, indicating enhanced nitrogen immobilization. The carbon treatment altered the beta diversity of soil fungi and bacteria and reduced fungal alpha diversity estimated by the Shannon index. The study results indicate that high carbon substrates can be used to modify plant-microbial competition for soil nitrogen with important implications for developing sustainable weed management practices. • High-carbon soil amendments immobilized soil available nitrogen. • Nitrogen-responsive plant growth was reduced in soils indicating nitrogen immobilization. • Soil carbon amendments enriched for distinct bacterial and fungal communities. • Fungal alpha diversity was consistently reduced in carbon-amended soils. [ABSTRACT FROM AUTHOR]

Antimony (Sb) is known for its severe and extensive toxicity, and earthworms are considered important indicator organisms in soil ecosystems. Therefore, the present study investigated the mechanism of toxicity of the Sb at different concentrations (50, 200 mg/kg) on earthworms using biochemical indicators, pathological sections, as well as metabolomics and transcriptomics analyses. The results showed that as the exposure concentration increased, both the antioxidant system of earthworms, extent of intestinal damage, and their metabolomic characteristics were significantly enhanced. In the 50 and 200 mg/kg Sb treatment group, 30 and 177 significant differentially changed metabolites (DCMs) were identified, respectively, with the most DCMs being down- and up-regulated, respectively. Metabolomics analysis showed that the contents of dl-tryptophan, glutamic acid, glycine, isoleucine, l-methionine, involved in the protein digestion and absorption as well as aminoacyl-tRNA biosynthesis were significantly up-regulated under the 200 mg/kg treatment. At the transcriptional level, Sb mainly affected the immune system, nervous system, amino acid metabolism, endocrine system, and carbohydrate metabolism in earthworms. The integration of transcriptomic and metabolomic data indicated that high doses of Sb regulated the metabolites and genes related to the oxidative phosphorylation pathway in earthworms. Overall, these results revealed global responses beyond the scope of conventional toxicity endpoints and facilitated a more in-depth and comprehensive assessment of the toxic effects of Sb. [Display omitted] • The toxicity of Sb(III) on P. guillelmi was evaluated at the molecular level. • T-AOC, GST activity, MT, and MDA content were significantly increased by 200 mg/kg Sb. • Sb affects the earthworm nervous system, immune system, oxidative stress. [ABSTRACT FROM AUTHOR]

Excessive nanoplastics not only pose a direct threat to the environment but also have the propensity to adsorb and interact with other pollutants, exacerbating their impact. The coexistence of nanoplastics and heavy metals in soils is a prevalent phenomenon. However, limited research existed about the joint effects of the two contaminants on soil organisms. In this paper, we ascertained the combined toxicity of polystyrene nanoplastics (PS-NPs) and copper (Cu2+) on soil organisms (Caenorhabditis elegans) at quantities that were present in the environment, further exploring whether the two toxicants were synergistic or antagonistic. The outcomes manifested that single exposure to low-dose PS-NPs (1 μg/L) would not cause significant damage to nematodes. After treatment with PS-NPs and Cu2+, the locomotion ability of nematode was impaired, accompanied by an elevation in reactive oxygen species (ROS) level and a biphasic response in antioxidant enzyme activity. Moreover, combined exposure to PS-NPs and Cu2+ induced the mRNA up-regulation of vit-6 , cyp-35a2 , hsp-16.2 , age-1 , and cep-1 , both of which were stress-related genes. The comparative analysis between groups (with or without PS-NPs) revealed that the combined exposure group resulted in significantly greater toxic effects on nematodes compared with Cu2+ exposure alone. Furthermore, the addition of PS-NPs influenced the metabolic profiles of Caenorhabditis elegans under Cu2+ stress, with numerous differential metabolites associated with oxidative damage or defense mechanism. Overall, these findings manifested that PS-NPs at the expected environmental concentration elevated Cu2+ toxicity on nematodes. [Display omitted] • Exposure to low-dose PS-NPs (1 μg/L) did not cause significant damage to C. elegans. • The toxicity of Cu2+ to nematodes was closely associated with oxidative damage. • PS-NPs at the expected environmental concentration elevated Cu2+ toxicity on C. elegans. [ABSTRACT FROM AUTHOR]