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Because the use of synthetic agrochemicals is generally not allowed in organic crop production systems, growers rely on natural substances and processes, such as microbial control, to suppress insect pests. Reduced tillage practices are associated with beneficial soil organisms, such as entomopathogenic fungi, that can contribute to the natural control of insect pests. The impacts of management, such as tillage, in a cropping system can affect soil biota in the current season and can also persist over time as legacy effects. We investigated the in-season and legacy effects of soil management in four, three-year organic feed grain and forage production systems that varied in number and intensity of soil disturbances on the relative prevalence of the entomopathogenic fungus, Metarhizium robertsii. Employing sentinel bait assays with Tenebrio molitor and Galleria mellonella, we found that relative prevalence, measured as infection rate of sentinel insects, was lowest in systems utilizing a shallow high-speed disk (G. mellonella: 14%; T. molitor: 23%) in the current and previous seasons compared to systems that included inversion and non-inversion tillage (G. mellonella: 22%; T. molitor: 34%) or no-till planting (G. mellonella: 21%; T. molitor: 30%,). There was no difference in prevalence in systems that included the use of a high-speed disk compared to a perennial hay crop (G. mellonella: 16%; T. molitor: 28%). There were no negative legacy effects of inversion tillage on the prevalence of M. robertsii in subsequent crops. Sentinel assays with G. mellonella (19%) produced overall lower estimates of relative prevalence of M. robertsii than T. molitor (29%) but the association of relative prevalence with environmental variables was greater in assays with G. mellonella. We suggest that the use of occasional inversion tillage is not damaging to populations of M. robertsii in soil and that surveys using assays with multiple sentinel insect species will improve our ability to understand the effects of agricultural practices on entomopathogenic fungi. [ABSTRACT FROM AUTHOR]

Closely related species often conserve similar niches despite interacting negatively. We suggest that close relatives may interact positively via ecosystem feedbacks: leaf litter produced or exposed in a closely related neighbourhood (low phylogenetic isolation) may decompose more quickly, leading to more rapid nutrient recycling. We studied decomposition of leaf litter of oaks Quercus petraea across 8 and 14 months, reciprocally transplanting leaf litters between low and high phylogenetic isolation to distinguish between effects mediated by leaf litter quality and by decomposition environment. We found that, by affecting litter quality, phylogenetic isolation reduced decomposition across 14 months (loss of litter mass and C). Moreover, by affecting litter quality and decomposition environment, phylogenetic isolation reduced microbial biomass and extensively altered relationships between C and N losses and abundances/diversities of different soil organisms across 8 and 14 months. Phylogenetic isolation was to a large extant driven by percentage of gymnosperms, explaining the decomposition‐environment mediated effects. Such environment‐mediated effects reflected decreasing soil humidity and pH with phylogenetic isolation, while litter‐quality mediated effects reflected decreasing leaf phytophagy or increasing leaf phenolics. Tree‐species richness, in contrast, did not explain effects of phylogenetic isolation, and had little effect overall. To conclude, coexistence of oaks with distant relatives partly impedes recycling of leaf litter and re‐organizes the trajectories of this recycling. In contrast, oaks coexisting with close relatives may profit from a positive ecosystem feedback through increased nutrient recycling, possibly contributing to the conservation of the oak's niches. We suggest that such a positive ecosystem feedback among close relatives might exist in other late successional tree species. [ABSTRACT FROM AUTHOR]

The Iberian Peninsula and the South of France are a centre of diversification of the Lumbricidae family, which has many endemisms and basal genera in the phylogeny of lumbricids in that area. Two basal and endemic genera of this area are Cataladrilus and Prosellodrilus. These genera are very poorly studied, and there are very few phylogenetic studies in which representatives of these genera have been included. In the case of Prosellodrilus, the type species has never been included in phylogenetic analyses. Therefore, in this study, after capturing specimens of different species of Cataladrilus and Prosellodrilus in their type localities (including the type species of both genera), a phylogenetic analysis was carried out using the molecular markers COI, 16S (mitochondrial) and 28S (nuclear). Sequences from other lumbricid genera obtained in previous studies were also included, with the purpose of testing the monophyly of Prosellodrilus and Cataladrilus and recovering their phylogenetic relationships with other basal genera. As a result, it was possible to demonstrate that both genera are monophyletic and, therefore, valid. Both genera are evolutionarily very close and are found very close to other basal genera such as Castellodrilus and Zophoscolex. Furthermore, by calculating the ancestral area of Prosellodrilus it was possible to observe that the origin of the genus is located in an area between Sardinia and eastern France and that the genus predates the separation of Sardinia from France and the formation of the Pyrenees, which could explain the presence of P. festae in Sardinia and the presence of this genus on both sides of the Pyrenees. Furthermore, if the geological age of the Pyrenees and its formation process are studied in detail, it can be observed how the different stages of formation of this mountain range largely coincide with the distribution of the different species of Prosellodrilus. [ABSTRACT FROM AUTHOR]

• HTL solids met Danish contaminant limits and showed moderate toxicity in ecotoxicity tests. • Phosphate fertilizers were extracted from HTL solids with high recovery and bioavailability. • Large-scale production of HTL mineral products using pilot plant for field trial studies. • Downstream processing of HTL mineral products to synthesize commercial fertilizers. Sustainable agriculture is vital for reducing reliance on harmful chemical fertilizers and ensuring environmental and economic stability. Integrating Hydrothermal Liquefaction (HTL) with anaerobic digestion (AD) can improve biomass efficiency and recovery of both energy (liquid fuels) and valuable nutrients, essential for achieving circular bioeconomy. Biogas digestate is rich in nutrients, and the HTL process can concentrate these nutrients in the solid phase, making the resulting product well-suited for agricultural applications. In this study, HTL solids were produced from biogas digestate using a continuous bench-scale HTL pilot plant to assess their potential as direct-use fertilizers. The optimal conditions for keeping contaminants within allowable limits in mineral products were identified by testing various reaction temperatures, with and without the use of a catalyst. The elemental composition of mineral products (2179 and 2181) showed high carbon varying from 51.61 and 48.41 wt%, phosphorus varying from 3.46 to 3.07 wt% and sufficient nitrogen contents varying from 1.19 to 1.13 wt%. Furthermore, carbon stability of 2179 and 2181 was measured to be 1.2 and 0.3, respectively, which indicated good quality of HTL mineral products. Organic contaminants and heavy metals in HTL mineral products obtained after biocrude recirculation cycles using the HTL pilot plant were found to be close to or below the allowed limits set by Danish legislation. Avoidance (EC50 1.62 %) and seed germination (EC50 21.37 %) tests of the mineral product indicated a moderate level of biotoxicity and a substantial plant growth stimulation potential. A maximum amount of 39 kg/ha for 2179 and 55 kg/ha for 2181 is suitable for field use without harming soil organisms. The phosphates recovery from mineral products into phosphorus-based fertilizers like struvite and hydroxyapatite using mild acids and bases as leaching agents showed around 90 % phosphates recovery and 70 % bioavailability. The synthesized fertilizers were characterized using X-ray diffraction (XRD) spectroscopy. Overall, HTL mineral products present a sustainable alternative for enhancing soil fertility, reducing reliance on harmful chemical fertilizers, and supporting both environmental and economic stability, thereby contributing to a circular economy. [ABSTRACT FROM AUTHOR]

Diana Harrison Wall, a prominent figure in soil biodiversity and former President of the Ecological Society of America, passed away in 2024. Her groundbreaking research in soil ecology spanned over 50 years, focusing on soil biodiversity, ecosystem functioning, and climate change. Dr. Wall's contributions to understanding soil biodiversity and ecology have been crucial in comprehending ecosystem dynamics and global changes, while also advocating for equity, diversity, and public awareness in science. Her legacy includes numerous awards, leadership roles in scientific organizations, and mentoring of students and early career scientists, making her a respected and influential figure in the field of ecology. [Extracted from the article]

The prevalence of microplastics in soil has recently attracted substantial interest as they pose a major threat to the agricultural ecosystem. Microplastics (MPs), though widely found in marine habitats and explored in detail, their presence in agricultural soil remains relatively unexplored. Microplastics are entering the environment either directly through manufactured particles or those originating from the breakdown of larger macroplastics. In soil, microplastics can be transported both horizontally and vertically through the soil fauna. Hence, in order to understand the possible threats posed by microplastics in soil to the environment, this review aims in conducting a meta – analysis to integrate the recent studies in sources, fate and migration of microplastics into agriculture, impacts on soil health, trophic transfers to food chains and the associated adverse impact on soil biota. Results reveals that major sources of microplastics in soil includes sludge followed by wastewater and mulch film. Its effect on soil properties depends on the soil type, size, concentration and type of polymer. Though the occurrence of microplastics in soil has been reported in various countries, its presence in various other countries is still unexplored. Furthermore, several studies validates the effect of microplastics on soil biota at various trophic stages and even endanger human health by food chains. MPs exert both ecotoxicity and genotoxicity in plants. It delays germination by affecting both the vegetative and reproductive growth of plants. It also affects the ecosystem through the sorption of organic and inorganic pollutants. Nevertheless, detailed insights on the effect of microplastics on soil beneficial organisms and the trophic transfer onto humans requires further studies. [ABSTRACT FROM AUTHOR]

ABSTRACT Plants exude a wide variety of compounds into the rhizosphere, modulating soil functioning and diversity. The number of studies investigating exudation has exponentially increased over the past decades. Yet, the high inter‐study variability of the results is slowing down our understanding of root–soil interactions. This variability is partly due to the absence of harmonized methodologies to collect and characterize exudation. Here, we discuss how various experimental aspects influence exudation profiles by performing a literature review, and we suggest best practices for different experimental setups. We discuss state‐of‐the‐art of spatially resolved exudate collection, collection in controlled versus field conditions and plant growth setups ranging from hydroponics to soil. We highlight the importance of preparing experimental blanks, in situ versus ex situ exudate collection, various collection media and timing of collection, exudate storage and processing and analytical considerations. We summarize best practices for experimental setup and reporting of parameters in an easily accessible table format to facilitate discussion of best practices in the field. An increased standardization in the field together with the systematic studies suggested will improve our knowledge of how plant exudation shapes interactions with organisms in soil. [ABSTRACT FROM AUTHOR]

Plant roots host a range of fungi, including mycorrhizal fungi and endophytes. A new study shows that mucoromycotinan fine root endophytes can selectively utilise organic nitrogen, keep the carbon, transfer nitrogen to host and receive carbon from plants. [ABSTRACT FROM AUTHOR]

Microplastics (MP) in the environment has attracted extensive attention due to their ubiquitous occurrence and potential toxic effects; but less attention has been given to the removal technologies of MP in different environmental media. This review covers the sources, ecotoxicities, and removal technologies of MP in soil and water environments reported in previous studies to derive the future research directions for MP removal technologies. Previous studies reported various sources contribute to MP present in soil and water environments, indicating that the source control may be a better strategy than contaminated media treatment for management of MP contamination. Similarly, different terrestrial and aquatic organisms have been used to determine the toxic effects of MP with different characteristics. Previous ecotoxicity studies of MP on soil organisms cover only a small number of species compared to that of MP on aquatic organisms. Therefore, further studies are necessary to investigate the ecotoxic effects of MP on a broader range of soil organisms. Also, since the characteristics of MP are diverse, more ecotoxicity studies in both water and soil environments are required. The review provides an overview of various removal technologies for MP in soil and water and identifies gaps in existing studies. Although more studies have been conducted for removal of MP in water than in soil, they remain in their early stages. More studies are needed for removal of MP removal in soil than in water. With MP in water, most studies have been carried out on a lab scale with artificial wastewaters, thus, studies with natural waters in a pilot or field scale are required. Overall, this review highlights the need for further studies on MP removal technologies for real world applications. [ABSTRACT FROM AUTHOR]

Traditionally, leaf litter has been recognized as the main driver of the soil food web, but more recently roots have been shown to play an important role in fuelling soil organisms. Root functional traits were shown to have direct effects on microbes and Nematoda, but many knowledge gaps remain such as the effects of root traits on Collembola. Here, in a microcosm experiment, we studied the tri‐trophic interactions between roots, microbes and Collembola in relation to 10 plant species individually. Eleven root traits were measured to test whether they have an influence on Collembola and microbe community structure and Collembola functional structure based on six traits. The interactions between microbes and Collembola were also tested. Our results show that plant species identity significantly influences the structure of Collembola communities, and this variation is primarily explained by root traits and microbial communities. Collembola feeding traits based on mandibular morphology were useful to identify top‐down control on microbial communities. Our study also suggests that root traits such as fine root length and root diameter modify Collembola–microbe interactions, hypothetically by modifying soil porosity. Overall, we obtained better results by looking at the whole system, rather than looking at bi‐trophic interactions. This illustrates the importance of a holistic approach when studying biotic interactions in soil ecosystems. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The document discusses various research studies presented at the Southwestern Ontario Regional Meeting in 2024. Topics include quantifying shifts in virulence of soybean cyst nematode, identifying causal pathogens of root rot in dry beans, evaluating the impact of Heterodera glycines on dry beans, and assessing the suppression of clubroot on cabbage by Beauveria bassiana. Other studies focus on the relationship between nutrient status and Stemphylium leaf blight in onions, the detection of plant pathogens via DNA metabarcoding, and genetic mechanisms in Brassica napus-Verticillium longisporum interactions. These studies aim to improve management strategies for plant diseases and enhance crop protection. [Extracted from the article]

Red chili consumption in Indonesia has increased every year. However, with large chili production to meet large consumption, land conversion for various purposes has reduced the harvested area. The efforts to increase the harvested area of chili using Inceptisols soil by providing nutrient solutions to overcome the infertility of the soil using its nutrients. This experiment aims to determine the effect of nutrient solution application on population of phosphate-solubilizing bacteria, phosphorus availability, phosphorus uptake, growth and yield of Red Chili (Capsicum annuum L.) in Inceptisols. The experiment was conducted from August 2023 to February 2024 at Ciparanje Experimental Field, Faculty of Agriculture, Padjadjaran University, and the analysis process was conducted at the Laboratory of Soil Biology, and Soil Chemistry and Plant Nutrition, Department of Soil Science and Land Resources, Faculty of Agriculture, Universitas Padjadjaran., using a factorial randomized block design with two factors, nutrient solutions concentrates (1200, 1600, 2000 ppm) and nutrient solutions doses (200, 400, 600 mL), resulting in nine treatments and three replications. The results showed that the treatment of nutrient solution concentration and dose increased the number of fruits per plant, fruits weight per plant, and yield of chili with grade A. Treatment with 2000 ppm concentrate + 600 mL dose gave the best results on the number of fruits per plant (44.7 fruits), fruit weight per plant (725g), and grade A chili yield (73 fruits). [ABSTRACT FROM AUTHOR]

Background and aims: Shrub effect with climate change is known to alter alpha diversity of organism groups at the taxonomic level, but how it influences the beta diversity of soil organisms, particularly functional level, remains poorly understood. Here, we investigated the abundant nematode fauna to assess the shrub effects on alpha and beta diversity at both taxonomic and functional level in sites on the Qinghai-Tibet Plateau. Methods: We collected three functional traits (i.e., diet, body mass and life-history) associated with resource acquisition, dispersal ability, reproduction and the rate of nutrient utilization. We calculated the functional alpha and beta diversity of nematode communities under shrubs and open spaces using kernel density n-dimensional hypervolumes and combined it with taxonomic diversity to disentangle the spatial patterns and community assembly of nematode communities. Results: Shrubs significantly increased taxonomic richness, but not functional richness. However, shrubs reshaped broad-scale nematode functional richness and ecological indices along climatic gradients. Shrubs significantly decreased the taxonomic and functional beta diversities of nematode communities, generating biota homogenization. The parallel changes of taxonomic and functional beta diversities were driven by distinct processes. Replacement dominated taxonomic beta diversity variation, while richness difference dominated functional beta diversity variation. Conclusion: Our findings show that shrubs were able to filter functional traits and limit the dispersal of species assemblages that exhibit such traits, thus causing taxonomic and functional homogenization of soil nematodes on the Qinghai–Tibet Plateau. Our findings advance understanding of the spatial patterns of belowground communities for taxonomic and functional aspects. [ABSTRACT FROM AUTHOR]

Background and aim: Litter and soil characteristics influence the abundance and activities of decomposers and detritivores, thereby affecting C accumulation. The relationship between the chemical composition of soil organic matter and soil organisms is still unclear. The study aims to investigate how the quality and quantity of litter and soil organic matter influence C accumulation and the relationships between organic matter quality and bacteria, fungi and microarthropods in litter and soil. Materials and methods: Litters and soils from 24 sites were analysed for the abiotic (pH, water content, total C and N content and the chemical composition of soluble C: carbohydrate, alkyl, O-alkyl, aromatic and carboxyl groups) and the biotic characteristics (bacterial and fungal abundances, urease and β-glucosidase, microbial respiration, microarthropod community). Results: Litter had a high carbohydrate and low C contents, whereas soil had higher content of recalcitrant compounds (aromatic and carboxylic groups) and C. Whitin substrate types, higher C content was found in litter from shrubs and in soil under sclerophyllous evergreens. Bacterial abundances were lower in litter than in soil, whereas microbial respiration, enzymatic activities, microarthropod densities and predator abundances were higher in litter than in soil. Microbial abundances and activities were strongly related to total C and N concentrations in both litter and soil, while the microarthropod community was positively correlated with soluble C recalcitrant compounds in soil. Conclusions: Soils showed a high capacity for C accumulation due to the high content of recalcitrant compounds. In soil, the microarthropod community, more than bacteria and fungi, was positively correlated with the quality of organic matter. [ABSTRACT FROM AUTHOR]

Recently, there has been growing interest by farmers and researchers in various agroecological approaches enhancing biodiversity and conservation including the use of natural herbicides derived from fungi to provide adequate weed control. This change is driven by growing concerns about herbicide resistance, environmental impacts and regulatory requirements. This review summarizes the results of various studies and highlights the efficacy and benefits of fungal bioherbicides in weed control. Fungi-based bioherbicides utilize the natural weed suppression capability of selected fungi to reduce weed density and competitiveness without completely eradicating the plants and such an approach is at the core of agroecology. Bioherbicides contribute to conservation by providing an environmentally friendly alternative to chemical herbicides. By reducing the reliance on synthetic chemicals, fungal bioherbicides help preserve soil health, water quality and protect non-target species, including beneficial organisms such as pollinators and soil microbes. They also promote biodiversity by selectively targeting specific weed species, leaving native plants and other organisms unharmed and favoring diversified weed flora without the dominance of a few species. Despite their promising potential, bioherbicides face several challenges, including delayed action, production difficulties and the potential toxicity of certain fungal toxins to mammals. This review highlights the growing adoption of fungal bioherbicides as an eco-friendly component of Integrated Weed Management (IWM). Further research is necessary to identify optimal fungal strains for controlling persistent weeds without putting at risk the overall biodiversity and to develop improved formulations for enhanced efficacy. [ABSTRACT FROM AUTHOR]

This review examines the role of soil and sediment organisms as bioindicators in environmental pollution assessment. As fundamental elements of terrestrial ecosystems, soils harbour a rich and diverse biodiversity that plays a key role in regulating ecological processes. The use of bioindicators provides a sensitive and specific approach to detecting the effects of chemical, biological, and physical pollutants on soil health. The review presents a detailed analysis of the types of contaminants commonly encountered, the soil organisms used as bioindicators, and the criteria for selecting the most appropriate bioindicators. It also discusses assessment methods, including soil sampling and analysis techniques, and the biological and ecological indices used to measure contamination. Regional case studies illustrate the practical application of bioindicators for assessing soil quality in different geographical contexts. The review also highlights current challenges to the use of bioindicators, such as technical limitations and the variability of organism responses, and suggests perspectives for future research, including technological innovation and the integration of bioindicators into environmental policy. [ABSTRACT FROM AUTHOR]

The prevalence of microplastics (MPs) in agricultural ecosystems poses a notable threat to dynamics of soil ecosystems, crop productivity, and global food security. MPs enter agricultural ecosystems from various sources and have considerable impacts on the physiochemical properties soil, soil organisms and microbial communities, and plants. However, the intensity of these impacts can vary with the size, shape, types, and the concentrations of MPs in the soil. Besides, MPs can enter food chain through consummation of crops grown on MPs polluted soils. In this study, we conducted a bibliometric analysis of 1636 publications on the effects of MPs on agricultural ecosystems from 2012 to May 2024. The results revealed a substantial increase in publications over the years, and China, the USA, Germany, and India have emerged as leading countries in this field of research. Social network analysis identified emerging trends and research hotspots. The latest burst keywords were contaminants, biochar, polyethylene microplastics, biodegradable microplastics, antibiotic resistance genes, and quantification. Furthermore, we have summarized the effects of MPs on various components of agricultural ecosystems. By integrating findings from diverse disciplinary perspectives, this study provides a valuable insight into the current knowledge landscape, identifies research gaps, and proposes future research directions to effectively tackle the intricate challenges associated with MPs pollution in agricultural environments. [ABSTRACT FROM AUTHOR]

Pharmaceuticals released into the aquatic and soil environments can be absorbed by plants and soil organisms, potentially leading to the formation of unknown metabolites that may negatively affect these organisms or contaminate the food chain. The aim of this study was to identify pharmaceutical metabolites through a triplet approach for metabolite structure prediction (software-based predictions, literature review, and known common metabolic pathways), followed by generating in silico mass spectral libraries and applying various mass spectrometry modes for untargeted LC-qTOF analysis. Therefore, Eisenia fetida and Lactuca sativa were exposed to a pharmaceutical mixture (atenolol, enrofloxacin, erythromycin, ketoprofen, sulfametoxazole, tetracycline) under hydroponic and soil conditions at environmentally relevant concentrations. Samples collected at different time points were extracted using QuEChERS and analyzed with LC-qTOF in data-dependent (DDA) and data-independent (DIA) acquisition modes, applying both positive and negative electrospray ionization. The triplet approach for metabolite structure prediction yielded a total of 3762 pharmaceutical metabolites, and an in silico mass spectral library was created based on these predicted metabolites. This approach resulted in the identification of 26 statistically significant metabolites (p < 0.05), with DDA + and DDA − outperforming DIA modes by successfully detecting 56/67 sample type:metabolite combinations. Lettuce roots had the highest metabolite count (26), followed by leaves (6) and earthworms (2). Despite the lower metabolite count, earthworms showed the highest peak intensities, closely followed by roots, with leaves displaying the lowest intensities. Common metabolic reactions observed included hydroxylation, decarboxylation, acetylation, and glucosidation, with ketoprofen-related metabolites being the most prevalent, totaling 12 distinct metabolites. In conclusion, we developed a high-throughput workflow combining open-source software with LC-HRMS for identifying unknown metabolites across various sample types. [ABSTRACT FROM AUTHOR]

Fungal communities are important components of soil biology and play crucial roles in multiple ecosystem functions and services; therefore, they can be used as effective indicators of soil function in stockpiled reclamation soils. We profiled the fungal communities of seven stockpiles of different ages (0.5, 1.5, 2, 5, 7, 11, and 28 years old) at various soil depths (0–300 cm) in two oil sand extraction locations in northern Alberta. Fungal communities of the stockpiles differed from the communities in the nearby undisturbed reference soils. The differences with the reference soils were more pronounced for the oldest and some of the younger stockpiled soils. Similar to previous studies, there was a decrease in fungal richness and overall diversity with increasing stockpile depth. Furthermore, soil stockpiling generated a shift in the functional composition based on inferred fungal guilds and trophic modes. Ectomycorrhizal fungi decreased and saprotrophic fungi increased in the stockpiles relative to the reference soils. Such a shift may have important implications for ecosystem functions and services associated with fungal communities, such as litter decomposition and plant growth promotion, when these stockpiles are used to reclaim ecosystems. Our results align with previous research identifying the negative effects of stockpiling on soil microbial communities, shed light on the soil functions that may be affected by this disturbance and their consequences for ecosystem functioning, and reflect the high sensitivity of fungal communities to soil disturbances like stockpiling. [ABSTRACT FROM AUTHOR]

Corpse decomposition affects soil organisms through the formation of "cadaver decomposition islands." Soil diazotrophic microbes possess essential ecological functions on nitrogen input and nutrient cycling in the terrestrial ecosystem. However, our knowledge about how soil diazotrophic communities respond to corpse decomposition is lacking. In this study, we focused on the succession patterns and biological interaction of nitrogen-fixing microorganisms during animal (Ochotona curzoniae) corpse decomposition in terrestrial ecosystems by targeting nifH gene with high-throughput sequencing. Our results revealed that corpse decomposition of pikas reduced the α diversity and significantly impacted the β diversity of diazotrophic community across different decomposition stages. The divergent succession of diazotrophic community occurred under corpse pressure. Furthermore, the relative importance of stochasticity to the community assembly was improved by corpse decomposition, while the importance decreased over decomposition time. Cadaver decay also simplified the diazotrophic networks and weakened the biological interactions among diazotrophic populations. Notably, NH4-N was the most important factor affecting diazotrophic community, followed by time and total carbon. This work emphasized that corpse decomposition perhaps influences the process of biological nitrogen fixation by altering soil diazotrophic communities, which is of great significance for understanding the terrestrial ecosystems' nitrogen cycle functions. Key points: • Corpse decomposition reduced the α diversity of diazotrophic community. • Corpse decomposition improved the stochasticity of diazotrophic community assembly. • Corpse decomposition weakened the interactions among diazotrophic populations. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata L. [Walp.]) cultivation encounters a plethora of challenges such as suboptimal productivity levels, declined income levels, and poor soil health under conventional fertilization systems. Therefore, the present field investigation was undertaken at the Research Farm, Department of Agronomy, CSKHPKV, Palampur in the rainy season of 2019 to evaluate eight combinations of organic farming and Zero Budget Natural Farming (NF) based inputs, i.e., Beejamrita (100 ml kg−1 of seed) + Jeewamrita (187.5 L ha−1); Beejamrita (100 ml kg−1 of seed) + GhanaJeewamrita (250 kg ha−1); Beejamrita (100 ml kg−1 of seed) + Jeewamrita (187.5 L ha−1) + GhanaJeewamrita (250 kg ha−1); farm yard manure (FYM) 10 Mg ha−1; FYM (10 Mg ha−1) + GhanaJeewamrita (250 kg ha−1); biofertilizers (PSBs and Rhizobium at 10 g kg−1 of seed) + FYM (10 Mg ha−1) + vermiwash (1:10); biofertilizers (PSBs and Rhizobium at 10 g kg−1 of seed) + vermicompost (7.5 Mg ha−1) + vermiwash (1:10); absolute (untreated) control; in a randomized complete block design with three replications for their influence over cowpea productivity, profitability, and energetics. The results of the investigation revealed that applying FYM (10 Mg ha−1) and GhanaJeewamrita (250 kg ha−1) in combination resulted in significantly higher grain yield(1,070.5 kg ha−1), economic net returns (766.61 USD ha−1), net energy gains (78,230 MJ ha−1), and considerably improved soil microbial biomass carbon (133.92 mg g−1 of soil), nitrogen (27.40 mg g−1 of soil), urease (52.20 (mg g−1 urea of soil h−1), and dehydrogenase activity (5.21mg g−1 TPF of soil h−1). Improved soil biological properties in the present study might have been responsible for considerable increment in cowpea yield and profitability. Therefore, in-combination application-based module of FYM (10 Mg ha−1) and GhanaJeewamrita (250 kg ha−1) can be recommended for enhancing productivity and profitability of cowpea cultivation under North-Western Himalayan agro-ecological conditions. This study contributes valuable insights for organic input strategies in regions facing similar challenges. [ABSTRACT FROM AUTHOR]

Microorganisms are critical indicators of soil quality due to their essential role in maintaining ecosystem services. However, anthropogenic activities can disrupt the vital metabolic functions of these microorganisms. Considering that soil biology is often underestimated and traditional assessment methods do not capture its complexity, molecular methods can be used to assess soil health more effectively. This study aimed to identify the changes in soil microbial diversity and activity under different cocoa agroforestry systems, specially focusing on taxa and functions associated to carbon and nitrogen cycling. Soils from three different cocoa agroforestry systems, including a newly established agroforestry with green fertilization (GF), rubber (Hevea brasiliensis)–cocoa intercropping (RC), and cocoa plantations under Cabruca (cultivated under the shave of native forest) (CAB) were analyzed and compared using metagenomic and metaproteomic approaches. Samples from surrounding native forest and pasture were used in the comparison, representing natural and anthropomorphic ecosystems. Metagenomic analysis revealed a significant increase in Proteobacteria and Basidiomycota and the genes associated with dissimilatory nitrate reduction in the RC and CAB areas. The green fertilization area showed increased nitrogen cycling activity, demonstrating the success of the practice. In addition, metaproteomic analyses detected enzymes such as dehydrogenases in RC and native forest soils, indicating higher metabolic activity in these soils. These findings underscore the importance of soil management strategies to enhance soil productivity, diversity, and overall soil health. Molecular tools are useful to demonstrate how changes in agricultural practices directly influence the microbial community, affecting soil health. [ABSTRACT FROM AUTHOR]

The use of remineralizers has been highlighted as a viable option for alternative fertilizer sources. However, it is necessary to study the impacts of its use on the biological quality of the soil. The objective of this study was to evaluate the effect of the remineralizer on the diversity of the edaphic fauna. The research was carried out in a randomized block design, with four replications and the following treatments: T0: control; T1: 100% of N-P-K; T2: Fertilization only with remineralizer; T3: 75% of N-P-K + remineralizer; T4: 75% of N-P-K + remineralizer + Azospirillum spp.; T5: 75% of N-P-K + remineralizer + Bacillus spp.; T6: 75% of N-P-K + Azospirillum spp.; T7: 75% of N-P-K + Bacillus spp. The soil fauna was sampled two times of the year using pitfall traps, and soil samples were collected at the same points for explanatory variables (chemical and microbiological attributes of the soil). The diversity of groups varied between the collection times, and the most frequent were Collembola, Formicidae, and Acari. The use of remineralizer favored the diversity of groups and the establishment of Collembola populations compared to treatments with conventional fertilizer. [ABSTRACT FROM AUTHOR]

In the current European Union pesticide risk assessment for soil organisms, effect endpoints from laboratory studies (Tier 1) and field studies (higher‐tier risk assessment) are compared with predicted environmental concentrations in soil, derived from the proposed use pattern. The simple but conservative initial Tier 1 risk assessment considers a range of worst‐case assumptions. In contrast, the higher‐tier assessment focuses on specific conditions tested in the corresponding field study. Effect modeling, such as toxicokinetic–toxicodynamic (TKTD) modeling, is considered a promising future tool to address uncertainties in soil risk assessment, such as extrapolation to different ecological, pedo‐climatical, or agronomical situations, or to serve as an intermediate tier for potential refinement of the risk assessment. For the implementation of TKTD modeling in soil organism risk assessment, data on earthworm growth and reproduction over time are required, which are not provided by the standard Organisation for Economic Co‐operation and Development (OECD) 222 laboratory test. The underlying study with carbendazim presents a new earthworm cocoon test design, based on the OECD 222 test, to provide the necessary data as input for TKTD modeling. This proposed test design involves destructive samplings at days 7, 14, 21, and 28, enabling the determination of growth, cocoon number, and the number of juveniles hatched per cocoon in 7‐day intervals. The new cocoon test allowed the disentanglement of the toxic effect of carbendazim in earthworms: At the highest concentration prominent effects on growth and reproductive output were observed, and the number of cocoons was significantly reduced compared to control. The results highlighted different physiological modes of action: effect on growth via higher maintenance costs as a primary mode of action as well as a reduced number of cocoons (effect on reproduction) and a lower number of juveniles hatching from each cocoon (hazard during oogenesis) as a secondary mode of action. We provide an example of how this new test's data can be used to feed a dynamic energy budget theory–TKTD model of Eisenia fetida. We also validate it against the original OECD 222 test design, outlining its potential future use in soil risk assessment. Environ Toxicol Chem 2024;43:2377–2386. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Presence of cadmium in soil affects the growth status of plants; research on the underlying mechanism has focused on its lethal and sublethal consequences in plants, ignoring the impacts of soil organisms. Therefore, this study designed a microorganism – earthworm – plant ecosystem, investigated the influence of Cd (0, 0.3, 1.0, and 3.0 mg kg−1) on the growth of Arabidopsis thaliana in the presence of earthworms (Eisenia fetida), and revealed the mechanisms from the perspective of altered relationships among different soil organisms. In this study, there was no significant difference in the death rate of earthworms with low Cd addition concentration, but the microorganisms in earthworms and soil microorganisms changed, abundance of Actinomycetes in soil increased, while Planctomycetes decreased, Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microorganisms affect soil pH, which in turn affects soil physicochemical properties and the form of cadmium in soil. Compared with the control, soil pH significantly decreases under cadmium stress, Under 0.3 mg kg−1 treatment, soil total nitrogen, available phosphorus and total potassium are 181.11, 5.09, 51.90, and 7.55 mg kg−1, respectively, They were significantly higher than control group. Improved the growth environment of Arabidopsis thaliana and promoted the absorption of Cd in soil which affected the proportion of available Cd in the soil (when Cd was added at 1.0 mg kg−1, the proportion of available Cd in the soil decreased significantly from 95.05% to 49.40%). A. thaliana also absorbed more Cd, which increased Cd toxicity, and the reproductive growth of A. thaliana was enhanced, while vegetative growth was weakened.Compared with the control group (278.11 mg), the biomass of A. thaliana decreased significantly to 189.83 mg when Cd was supplemented at 0.3 mg kg−1. Therefore, the activities of and interactions among earthworms, plants, and microorganisms play important roles in reducing soil heavy metals and improving soil properties. HIGHLIGHTS: Under cadmium (Cd) stress, the relative abundance of Actinomycetes in soil increased, while Planctomycetes decreased. The relative abundance of Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microbial changes and E. fetida activity changed soil physical and chemical properties and reduced the ratio of soil available Cd. Microorganisms and E. fetida enhanced the reproductive growth and weakened the vegetative growth of Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

In navigating the biodiversity crisis, a major uncertainty is the conservation status of inconspicuous, yet megadiverse and functionally crucial, soil organisms. Massive datasets on soil biota are accumulating through molecular sampling approaches, but to date these datasets have provided only limited input into conservation planning and management. We investigated how environmental DNA (eDNA) data of soil macrofungi contribute to regional Red List assessments, which are currently based on fruiting bodies (hereafter, fruit‐bodies). In our test region of Estonia (northern Europe), which contained ~15,000 fruit‐body records for 1583 assessed species, an average soil sample increased the range estimates of Threatened and Near Threatened fungal species by 0.18%. Five hundred soil samples almost doubled their known localities and added 19% previously unrecorded species. However, even after accumulating >1000 soil samples, about half of the Threatened and Near Threatened species known by fruit‐bodies remained undetected through eDNA techniques. Effective conservation assessment of soil fungi thus requires both fruit‐body and eDNA data; therefore, special efforts are needed to make these data available to conservationists. [ABSTRACT FROM AUTHOR]

Since 2019, the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) has actively developed pesticide environmental risk assessment (ERA) frameworks adapted to Brazil's specific ecological contexts. This initiative, supported by funding from the Brazilian Ministry of Justice and in partnership with academic institutions, has led to a concerted effort to establish ERA protocols for various taxa, including birds and mammals, soil organisms, aquatic organisms, and reptiles and amphibians. The outcomes of this initiative were disseminated in two distinct workshops held in February and November of 2023, where the agency showcased its research to the technical‐regulatory community. This article synthesizes the proposals for birds and mammals and soil organisms. First, we summarize the agency's proposals for both focal and generic species to be incorporated into the ERA and the methodologies for calculating exposure of these taxa to pesticides through agricultural practices, encompassing seed treatment and foliar applications. On this occasion, IBAMA also disclosed the risk assessment tool that the agency is developing for birds and mammals. IBAMA highlighted the knowledge gaps that must be bridged to progress from preliminary (lower‐tier) to more comprehensive (higher‐tier) assessments. Regarding soil organisms, during the workshop, the presenters shared findings on the most prevalent species of earthworms and enchytraeids in Brazil. They emphasized the need for additional data collection on a regional scale. The agency has also proposed methods for estimating soil organism exposure to pesticides at a screening level and identified specific data gaps that could be addressed to refine assessments at higher tiers. In summary, the workshop communicated the progress in establishing ERA guidelines, which we encapsulate here to benefit the technical‐regulatory community. Integr Environ Assess Manag 2024;20:1793–1799. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: This brief communication summarizes the key messages conveyed at the workshop organized by the Brazilian Environmental Regulatory Agency (IBAMA) on ERA frameworks for birds and mammals in Brazil.This brief communication summarizes the key messages conveyed at the workshop organized by IBAMA on ERA frameworks for soil organisms in Brazil.The information summarized in this brief communication is a part of a very important shift in the Brazilian regulatory paradigm and may serve as a reference to the technical‐regulatory community, not only in Brazil but in Latin America as well.This brief communication may be very useful to the technical‐regulatory community in other regions (e.g., USA and Europe) by helping them to follow up on the regulatory changes in Brazil. [ABSTRACT FROM AUTHOR]

Copper is a trace element in plants and animals whose importance can be understood due to its role in different essential metabolic processes. Anthropogenic activities such as agriculture and mining are potential sources of pollution due to the emission of copper into the environment. Brazilian legislation ties soil quality to guideline values, among which the Prevention Value indicates the critical environmental limit for trace elements. The aim of this study was to obtain PVs for copper for two subtropical soils (Cambisol and Nitisol), given that the pedological richness was not considered when deriving the PVs contained in the federal normative. Reproduction assays followed ISO guidelines with the earthworm species Eisenia andrei and Perionyx excavatus, the enchytraeids Enchytraeus crypticus and Enchytraeus bigeminus and the springtails Folsomia candida and Proisotoma minuta. Results showed that the sensitivity of the organisms was greater in Cambisol. The most sensitive species were the earthworms, especially Perionyx excavatus (EC50 = 67.83 in Cambisol; EC50 = 264.96 in Nitisol). The springtails, on the other hand, were the least sensitive to contamination. These findings reinforce the need to include organisms from different ecological groups in ecotoxicological assessments. It was also observed that the PV adopted in federal legislation (= 60 mg kg−1) is in fact protective for the species and soils we evaluated, since the PVs we obtained based on the EC50 were 346.74 mg kg−1 in Nitisol and 134.05 mg kg−1 in Cambisol. It is important to note that our results do not exclude the need for evaluations with other subtropical soils, given the influence of their properties on the toxicity and bioavailability of copper to soil organisms. [ABSTRACT FROM AUTHOR]

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Arthropods may make a significant fraction of the total number of soil organisms. They function as plant litter transformers or ecosystem engineers, and thus contribute positively to soil health. The present study was conducted during the 2020--2022 at International Rice Research Institute, South Asia Regional Centre, Varanasi. Study investigates the impact of different farming methods- conventional (Scenario 1; Sc1), LINF- Low-input natural farming (Sc 2); BBEF- Biochar-based ecological farming (Sc 3); CROF- Climate-resilient organic farming (Sc 4); RF- Regenerative farming (Sc 5) practices on soil arthropod populations in rice-wheat systems. Study utilized pitfall traps across various experimental setups. The findings revealed a significant increase in arthropod diversity and abundance, particularly in organic farming scenarios, where the Formicidae family (ants) and the Araneae family (spiders) were most prevalent. In an organically rich soil system, the five most diverse groups (Isopoda, Myriapoda, Insecta, Acari, and Collembola) were reported. This increase can be attributed to the nutrient-rich amendments that positively influence soil organisms. This study highlights a gradual increase in specific taxa, such as cockroaches, spiders, ants, and grasshoppers, following the transition to organic farming. Principal component analysis (PCA) further revealed distinct arthropod distribution patterns in the different farming systems, indicating the unique ecological impact of each method. Interestingly, predator populations in zero-till wheat fields under regenerative agriculture were greater than those in conventionally tilled fields. These results underscore the substantial role of organic and regenerative farming practices in promoting sustainable agricultural ecosystems. This study reveals the complex interplay between farming practices and arthropod dynamics and highlights the ecological benefits of sustainable agricultural methods, emphasizing their potential to enhance biodiversity and ecosystem health. [ABSTRACT FROM AUTHOR]

Cadmium is a hazardous heavy metal that is commonly found in the soil and poses significant risks to soil organisms. The toxic effects of Cd on soil microorganisms and earthworms (Eisenia foetida) have been extensively studied, but most studies focused on high Cd pollution levels. Therefore, this study aims to investigate the different responses of soil organisms to moderate and low levels of Cd contamination. According to the study, the presence of 2.5 mg/kg of Cd had a significant impact on the microbial community's composition and diversity. The relative abundance of most microbes decreased, while the abundance of Firmicutes and Actinobacteriota showed a considerable increase. The LEFSE analysis revealed that the Bacillus genus of the Firmicutes phylum can serve as a biomarker in soil contaminated with 2.5 mg/kg of Cd. At the same time, the functional analysis of PICRUSt 2 shows that microorganisms found in polluted soil have a noticeable decrease in their ability to metabolize lipids. On the other hand, our findings indicate that Cd has a detrimental effect on the biomass of earthworms and induces oxidative stress in these animals. The activation of superoxide dismutase (SOD) and catalase (CAT) enzymes in earthworms was carried out to mitigate oxidative stress. The study found a strong positive relationship between SOD and both time and Cd pollution. However, CAT exhibited inhibition throughout the later stages of the experiment, particularly when exposed to relatively higher levels of pollution. The analysis of RNA in earthworms revealed that soil Cd pollution at a concentration of 2.5 mg/kg primarily impacts the cellular structure and function of earthworms. This pollution disrupts the integrity of the cytoskeleton structure, hampers DNA replication, and compromises the precision of cell signaling. Simultaneously, when compared to the control group, several metabolic pathways exhibited abnormalities. [ABSTRACT FROM AUTHOR]

Direct planting systems offer several benefits to the soil and plants, as reflected in soil organisms. The Arbuscular mycorrhizal fungi are extremely sensitive to environmental changes and can be used as indicators of soil quality. This study focused on the native diversity of mycorrhizae in the region. Thus, the objective of this work was to evaluate mycorrhizal colonization, spore density, soil glomalin content and species diversity in five wheat genotypes under direct and conventional planting systems. This work was carried out in the experimental area of Embrapa Cerrados, Planaltina, DF, Brazil. The rates of mycorrhizal colonization, spore density and easily extractable glomalin were evaluated, and species of arbuscular mycorrhizal fungi were identified in five wheat genotypes under direct and conventional planting. For all the genotypes under conventional planting, there was a decrease in mycorrhizal colonization, the number of spores in the rhizosphere and the amount of easily extractable glomalin. The composition of the arbuscular mycorrhizal fungal community differed among the wheat genotypes and management systems. The richness of morphospecies of AMF in the direct planting system was similar to that in the conventional system, with twelve species each, but the conventional system reduced root colonization and spore density. The most common species were A. scrobiculata, Si. tortuosum and G. macrocarpum, which were found in all the genotypes in both cultivation systems. [ABSTRACT FROM AUTHOR]

This document is a response to comments on a review of the ability of plantain to mitigate nitrogen leaching from pasture systems. The authors thank the respondents for their feedback and note that there is general agreement on many points. The authors argue that dilution is the main mechanism by which plantain reduces nitrogen leaching. They address specific points raised by the respondents and emphasize the need for further research and discussion in the scientific community. The New Zealand Journal of Agricultural Research is a reputable publication that covers a wide range of topics related to agriculture, providing valuable insights for researchers and practitioners in the agricultural industry. [Extracted from the article]

Summary Aboveground and belowground attributes of terrestrial ecosystems interact to shape carbon (C) cycling. However, plants and soil organisms are usually studied separately, leading to a knowledge gap regarding their coordinated contributions to ecosystem C cycling. We explored whether integrated consideration of plant and nematode traits better explained soil organic C (SOC) dynamics than plant or nematode traits considered separately. Our study system was a space‐for‐time natural restoration chronosequence following agricultural abandonment in a subtropical region, with pioneer, early, mid and climax stages. We identified an integrated fast–slow trait spectrum encompassing plants and nematodes, demonstrating coordinated shifts from fast strategies in the pioneer stage to slow strategies in the climax stage, corresponding to enhanced SOC dynamics. Joint consideration of plant and nematode traits explained more variation in SOC than by either group alone. Structural equation modeling revealed that the integrated fast–slow trait spectrum influenced SOC through its regulation of microbial traits, including microbial C use efficiency and microbial biomass. Our findings confirm the pivotal role of plant‐nematode trait coordination in modulating ecosystem C cycling and highlight the value of incorporating belowground traits into biogeochemical cycling under global change scenarios. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO-NPs) are commonly used in both commercial and agricultural sectors. As a result, ZnO-NPs are extensively discharged into soil ecosystems, creating a significant environmental issue. Therefore, it is crucial to assess their influence on the soil ecology to ensure its secure and enduring utilization in the future. The exact degree of toxicity associated with ZnO-NPs and their ionic form is still uncertain. To address the challenges, the study used the soil bioindicator earthworm species Eudrilus eugeniae as an experimental model to evaluate the effects of two zinc species (ZnO-NPs and ZnCl2) at 100, 250, 500, and 750 mg kg−1 and control (0 mg kg−1) in garden soil over 28 days. The investigation also examined the impact of exposure on survival, reproduction, neuro-biomarker, avoidance behavior, and accumulation. The highest avoidance rates were 27.5% for ZnO-NP and 37.5% for ZnCl2 at 750 mg kg−1. ZnCl2 treatment reduced juvenile production by 3.73 ± 1.73, while ZnO-NPs showed 4.67 ± 1.15. At 750 mg kg−1, soils with ZnCl2 (63.3%) demonstrated lower survival rates than those with ZnO-NPs (53.3%), likely because of higher Zn ion levels. After 28 days of exposure, ZnCl2 (536.32 ± 11 mol min−1) activated AChE enzymes more than ZnO-NPs (497.7 ± 59 mol min−1) at the same dose, compared to control (145.88 ± 28 to 149.41 ± 23 mol min−1). Nanoparticles and zinc ions bioaccumulated and reacted negatively with the neurotoxic marker AChE, affecting earthworm reproduction and behavior. However, earthworms exposed to ZnCl2 exhibited less intestinal Zn than those exposed to NPs. The present work contradicts the finding that ZnO-NPs have hazardous effects on soil organisms. The results indicate that earthworm E. eugeniae may significantly affect soil metal uptake from metallic nanoparticles (NPs). This may help design NP soil pollution mitigation strategies. The study offers valuable information for establishing a relationship between the environmental toxicity of ZnO-NPs and soil ecosystems. [ABSTRACT FROM AUTHOR]

The rise in global temperatures and increasing severity of heat waves pose significant threats to soil organisms, disrupting ecological balances in soil communities. Additionally, the implications of environmental pollution are exacerbated in a warmer world, as changes in temperature affect the uptake, transformation and elimination of toxicants, thereby increasing the vulnerability of organisms. Nevertheless, our understanding of such processes remains largely unexplored. The present study examines the impact of high temperatures on the uptake and effects of the fungicide fluazinam on the springtail Folsomia candida (Collembola, Isotomidae). Conducted under non‐optimum but realistic high temperatures, the experiments revealed that increased temperature hampered detoxification processes in F. candida, enhancing the toxic effects of fluazinam. High temperatures and the fungicide exerted synergistic interactions, reducing F. candida's reproduction and increasing adult mortality beyond what would be predicted by simple addition of the heat and chemical effects. These findings highlight the need to reevaluate the current ecological risk assessment and the regulatory framework in response to climate changes. This research enhances our understanding of how global warming affects the toxicokinetics and toxicodynamics (TK‐TD) of chemicals in terrestrial invertebrates. In conclusion, our results suggest that adjustments to regulatory threshold values are necessary to address the impact of a changing climate. [ABSTRACT FROM AUTHOR]

Climate change and anthropogenic activities have significantly contributed to the degradation of wet meadows on the Qinghai-Tibet Plateau (QTP). Soil nitrogen (N) availability is a crucial determinant of the productivity of wet meadow vegetation. Furthermore, soil microbial nitrogen functional genes (NFGs) are critical in the transformation of soil N. Nevertheless, the dynamics of NFGs in response to vegetation degradation, as well as the underlying drivers, remain poorly understood. In this study, wet meadows at varying levels of vegetation degradation on the QTP, categorized as non-degraded (ND), slightly degraded (SD), moderately degraded (MD), and heavily degraded (HD), were examined. Soil samples from depths of 0 to 10 cm and 10 to 20 cm were collected during different growth cycles (June 2020, August 2020, and May 2021). The analysis focused on NFGs involved in organic nitrogen fixation (nifH), archaeal and bacterial ammonia oxidation (amoA-AOA and amoA-AOB, respectively), and nitrite reduction (nirK), utilizing real-time fluorescence quantitative PCR. Our findings indicate a significant decline in the abundance of NFGs with intensified vegetation degradation, exhibiting notable spatial and temporal fluctuations. Specifically, the relative NFGs followed the pattern: nirK > amoA-AOA > amoA-AOB > nifH. Redundancy analysis revealed that vegetation cover was the primary regulator of NFGs abundance, accounting for 56.1%-57% of the variation. Additionally, soil total nitrogen, pH, and total phosphorus content were responsible for 38.5%, 28.2%, and 7% of the variability in NFGs, respectively. The (amoA-AOA + amoA-AOB + nirK) ratios associated with effective N transformation indicated that the vegetation degradation process moderately increased the nitrification potential. IMPORTANCE Our research investigates how the degradation of meadows affects the tiny organisms in soil that help plants use nitrogen, which is essential for their growth. In the Qinghai-Tibet Plateau, a region known for its unique ecosystems, we found that as meadows deteriorate--due to climate change and human activities--the number of these beneficial organisms significantly decreases. This decline could reduce soil fertility, impacting plant life and the overall health of the ecosystem. Understanding these changes helps us grasp how environmental pressures influence soil and plant health. Such knowledge is crucial for developing strategies to preserve these vulnerable ecosystems and ensure they continue to sustain biodiversity and provide resources for local communities. [ABSTRACT FROM AUTHOR]

Soil management using natural‐based approaches is becoming essential to minimize the use of synthetic agrochemicals and to ensure sustainability and resiliency of agriculture production. In this study, faba bean (Vicia faba L.) var. minor was used during three consecutive cropping years as green manure to restore soil fertility and biology and to improve the growth, yield and fruit quality parameters of pepper cv. 'Baklouti'. Following green manuring with faba bean, significant enhancements in the total nitrogen (N), the available phosphorus (P) and potassium (K) contents, the soil organic carbon (SOC) and the soil organic matter (SOM) levels were recorded. The alkaline phosphatase activity was also increased by 30.04% after faba bean var. minor incorporation into the soil in the third year. The β‐glucosidase and urease activities were increased by 26.8%–34.03% and 47.01%–71.7% in faba bean‐amended soil during the three‐year trials. Green manuring also enriched soil with total cultivable bacteria, Pseudomonas fluorescens, actinobacteria, total fungi and Aspergillus spp. as compared to control soil. Pepper growth and yield parameters were improved by 16.5–33.7% and 27.5% following green manure amendment, respectively. Vitamin C content, total soluble solids (TSS) and titrable acidity of green and red pepper fruits were 39.1%–50.7% and 7.2%–13.4% higher in green manured soil than in control. The calcium, potassium and phosphorus contents were significantly 4.7%–9.6%, 16.4%–18.1% and 41.2%–42.9% higher in red fruits of pepper plants grown on green manured soil. The plant growth and yield parameters together with the fruit biochemical and mineral characteristics were positively linked to NPK soil levels, SOC, SOM and soil microbial population's density and activity. This study clearly demonstrated the efficiency of green manuring using faba bean var. minor residues as potential alternative to agrochemicals for the enhancement of soil health status and the improvement of pepper growth, yield and fruit nutritional quality. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN), also known as light pollution, is a growing environmental problem worldwide. However, only a few studies have examined whether soil organisms that search for food at the surface at night can be affected by ALAN. We investigated the effects of ALAN on the above-ground foraging activity of anecic earthworms (Lumbricus terrestris), on the soil water infiltration and on the germination and growth of a cover crop (Phacelia tanacetifolia). In a full-factorial greenhouse experiment, we tested four factors: ALAN (about 5 lx during the night vs. total darkness), earthworms (two specimens vs. none), plant species (Phacelia alone vs. mixed with ragweed Ambrosia artemisiifolia) and sowing depth (surface-sown vs. sown in 5 cm depth). Data were analysed using multifactorial ANOVAs. Earthworms removed 51% less surface litter under ALAN than under dark conditions. ALAN had no effect on Phacelia germination but resulted in increased height growth and biomass production when the seeds were buried. Earthworms reduced Phacelia germination and biomass production. ALAN reduced water leaching through the experimental units, probably due to interactions between the subsurface casts and plant roots. We conclude that ALAN, as emitted from streetlights, can lead to complex ecological effects in ecosystems that merit further investigation. [ABSTRACT FROM AUTHOR]

Agricultural activities contribute to plastic pollution, with unintentional introduction and intentional use of plastic mulch films leading to the accumulation of microplastic particles in soils. The lack of removal techniques and scarce information on the effects on soil organisms, especially for biodegradable mulch films, necessitate an assessment of potential effects. This study aimed to elucidate the effects of mulch film microplastic on soil fauna by investigating reproduction output and subcellular responses before and after recovery from exposure. Two common soil organisms, Folsomia candida and Eisenia fetida, were exposed to petroleum-based polyethylene (PE) and biodegradable polylactic acid/polybutylene adipate terephthalate (PLA/PBAT) microplastic for 28 days, according to OECD guidelines 232 and 222, respectively. Juvenile numbers revealed no polymer- or concentration-dependent effects on E. fetida and F. candida reproduction after exposure to up to 5 and 10 g/kgdw soil, respectively. To provide a more sensitive and early indication of sublethal effects, subcellular responses in E. fetida were analyzed. Glutathione S-transferase (GST) activity increased with rising microplastic concentration; however, catalase (CAT), acetylcholine esterase (AChE) activity, and reactive oxygen species (ROS) did not differ from control levels. Further, the more environmentally relevant PE polymer was chosen for in-depth assessment of subcellular response after 28-day microplastic exposure and subsequent 28 days in uncontaminated soil with E. fetida. No significant differences in biomarker activity and stress levels were observed. We conclude that mulch film–derived microplastic did not adversely affect earthworm and collembolan species in this scenario, except for a slight induction in the detoxification enzyme glutathione S-transferase. [ABSTRACT FROM AUTHOR]