Soil Plant Research Articles

Composition of biopesticides for crop protection – current state and prospects (review)

Aim. To summarise and analyse available information on research into biopesticide compositions aimed at enhancing their effectiveness and to assess prospects for the development of this field so as to determine the influence of components on the effectiveness of biopesticides for agricultural crop protection.This review article presents the results of studies of components included in the compositions of microorganism‐based biopesticides based on a system analysis. It is noted that the selection of biopesticide components must be carried out in accordance with the requirements for products recommended for use in ecological and organic farming systems. It is indicated that the choice of optimal formulation is associated with the characteristics of the producer strains, their trophic needs and resistance to biotic and abiotic factors and with the characteristics of the biopesticide application technology (seed treatment, application to the soil or treatment of plants during vegetation), as well as the type of equipment used.Knowledge of the basic requirements for biopesticide formulations will help maintain the viability and biological activity of microbial agents during storage of biopesticides, taking into account the sensitivity of producer strains to environmental conditions. Selection of optimal carriers, adhesives, stabilisers, thickeners and synergists, taking into account the technology of application of the biopesticide and the target pathogen, will facilitate the development and appearance on the market of new biopesticides for protecting agricultural crops from diseases.

Microbiomes-Plant Interactions and K-Humate Application for Salinity Stress Mitigation and Yield Enhancement in Wheat and Faba Bean in Egypt’s Northeastern Delta

Salinity, resulting from climate change and excessive mineral fertilization, burdens farmers and negatively impacts soil and water ecosystems in the Northeastern Nile Delta. Organic and biological approaches are crucial for addressing these issues. This study examined the effects of individual and combined inoculations with cyanobacteria, yeast, and Arbuscular Mycorrhizal Fungi (AMF), with or without K-Humate and reducing Nitrogen, phosphorus and potassium (NPK) mineral fertilizers application rates to crop quality of wheat and faba bean. In preliminary laboratory experiments, the interactive effects of these microbiomes on plant antioxidant and soil enzyme production were examined under salinity stress. Results showed that co-inoculation, especially with K-Humate, yielded superior outcomes compared to individual inoculations. These findings were validated by a field trial conducted in saline-alkaline soil in the Northeastern Nile Delta region. All biological treatments 25% of recommended doses, and enhancing salinity tolerance, increasing yield, and improving enhanced rhizosphere microbial activity, including soil enzyme activity, AMF colonization, spore density, and the total numbers of bacteria, cyanobacteria, and yeast. These effects were further amplified by K-Humate and were more pronounced with combined inoculations than with individual ones, leading to improved soil fertility and significant increases in both crop quantity and quality compared to control treatments. The triple treatment, combining cyanobacteria, yeast, and mycorrhizae in the presence of K-Humate while reducing the mineral NPK rate by 75%, achieved superior increases in the productivity of wheat grains and faba bean seeds, reaching 54.72% and 128.92%, respectively, compared to the 100% NPK mineral control. This treatment also significantly improved crop quality, with notable increases in nitrogen, potassium, phosphorus, and protein percentages in wheat grains and faba bean seeds. Microbiomes-interaction increased potassium uptake over sodium, enhancing the plant’s potassium/sodium ratio and improving salt stress tolerance. This approach reduces reliance on costly mineral fertilizers, enabling bio-organic farming in marginal lands, optimizing resource utilization, and preserving natural resources.

Altitude Distribution Patterns and Driving Factors of Rhizosphere Soil Microbial Diversity in the Mountainous and Hilly Region of Southwest, China

The distribution characteristics of the microbial community in rhizosphere soils of different altitudinal gradients were explored to uncover ecological factors affecting microbial community composition. In this study, the community variations of bacteria and fungi in the rhizosphere soil of Chrysanthemum indicum L. were analyzed. Samples were distributed along an altitudinal gradient of 300–1500 m above sea level in the Fuling watershed of the Three Gorges Reservoir area, China. The analysis was conducted using Illumina MiSeq high-throughput sequencing and bioinformatics analyses. Through correlation analysis with ecological factors, the altitude distribution pattern and driving factors of soil microbial diversity in the mountainous and hilly region of Chongqing were explored. According to the results, the richness and diversity of rhizosphere soil bacteria increased with altitude, while fungi were the richest and most diverse at an altitude of 900 m. The composition of the microbial community differed among different altitudes. Actinobacteria, Proteobacteria, Acidobacteriota, Chloroflexi, Bacteroidota, Ascomycota, unclassified_k_Fungi, Basidiomycota, and Mortierellomycota dominated the microbial community in rhizosphere soil. Correlation analysis showed that the distribution of rhizosphere soil microbial communities correlated with soil ecological factors at different altitudes. Moisture, pH, total nitrogen, total potassium, available potassium, urease, and catalase were significantly positively correlated with rhizosphere soil bacterial α-diversity, while their correlations with fungi were not significant. Variation partition analysis showed that the combined effects of soil physical and chemical factors, enzyme activity, and microbial quantity regulated bacterial community structure and composition. Their combined contributions (19.21%) were lower than the individual effects of soil physical and chemical factors (48.49%), enzyme activity (53.24%), and microbial quantity (60.38%). The effects of ecological factors on fungal communities differed: While the soil physical and chemical factors (44.43%) alone had a clear effect on fungal community structures, their combined contributions had no apparent effect. The results of this study not only contribute to a deeper understanding of the impact mechanism of altitude gradient on the diversity of rhizosphere soil microbial communities, but also provide a scientific basis for the protection and management of mountainous and hilly ecosystems. It lays a foundation for the future exploration of the relationship between microbial communities and plant–soil interactions.

Analysis of coupled wetland soil–plant ecological stoichiometric characteristics of carbon, nitrogen, and phosphorus under different disturbance intensities

Analysis of coupled wetland soil–plant ecological stoichiometric characteristics of carbon, nitrogen, and phosphorus under different disturbance intensities

Warm growing season activates microbial nutrient cycling to promote fertilizer nitrogen uptake by maize

The influence of nitrogen (N) inputs on soil microbial communities and N uptake by plants is well-documented. Seasonal variations further impact these microbial communities and their nutrient-cycling functions, particularly within multiple cropping systems. Nevertheless, the combined effects of N fertilization and growing seasons on soil microbial communities and plant N uptake remain ambiguous, thereby constraining our comprehension of the optimal growing season for maximizing crop production. In this study, we employed 15N isotope labeling, high-throughput sequencing, and quantitative polymerase chain reaction (qPCR) techniques to investigate the effects of two distinct growing seasons on microbial communities and maize 15N uptake ratios (15NUR). Our results showed that the warm growing season (26.6 °C) increased microbial diversity, reduced network complexity but enhanced stability, decreased microbial associations, and increased modularization compared to the cool growing season (23.1 °C). Additionally, the warm growing season favored oligotrophic species and increased the abundance of microbial guilds and functional genes related to N, phosphorus, and sulfur cycling. Furthermore, alterations in the characteristics of soil microbial keystone taxa were closely linked to variations in maize 15NUR. Overall, our findings demonstrate significant seasonal variations in soil microbial diversity and functioning, with maize exhibiting higher 15NUR during the warm growing season of the double cropping system.

Responses of soil properties and foliar traits of a dominant tree species Pseudotsuga sinensis to rocky desertification in a karst ecosystem

Rocky desertification is a prevalent environmental challenge across karst landscapes that hinders regional sustainable development. Understanding how soil properties and plant traits respond to increasing levels of rocky desertification is crucial for developing effective restoration strategies. Here, we investigated soil characteristics and intraspecific leaf stoichiometric traits of Pseudotsuga sinensis across a gradient of rocky desertification in a karst ecosystem. We employed principal component analysis to assess changes in soil properties and leaf chemical traits and used leaf trait network analysis to explore shifts in trait network topology. Our results revealed that severe desertification sites had soil with high bulk density and pH, and low levels of available nitrogen, phosphorus, magnesium, as well as soil organic carbon. Leaf stoichiometry shifted markedly along the gradient, with elevated nitrogen limitation and cation imbalance in degraded sites. Trait network analysis showed that network diameter and modularity increased while connectance decreased with rocky desertification, indicating reduced integration among traits. On the other hand, higher adaptation capacity to environmental harshness under moderate level of rocky desertification was also observed. These findings suggest that both soil properties and leaf traits would experience substantial shifts across rocky desertification gradient, with increasing functional fragmentation and nutrient limitation as degradation intensifies. Based on our results, we propose management strategies targeted to different levels of rocky desertification to mitigate its negative impacts and promote ecosystem recovery.

The productivity of selected soybean cultivars grown using various cultivation methods

Soybean is an important legume crop globally due to its rich protein, oil content, and functional components. The purpose of this study was to evaluate the yield of selected soybean cultivars depending on cultivation methods. The three-year field experiment, conducted from 2018 to 2020 at the Agricultural Experimental Station in Kępa-Puławy, Osiny farm (Institute of Soil Science and Plant Cultivation – State Research Institute in Puławy), investigated these variations. The first experimental factor was the soil cultivation method: A – conventional tillage, B – reduced tillage, and C – strip tillage. The second variable was soybean cultivar: ‘Aldana’ and ‘Merlin’. The soybean cultivars were selected for their differing maturity rates: ‘Aldana’ (000) is an early cultivar, while ‘Merlin’ (000++) semi-late cultivar. The field experiment utilised a split-plot design on Luvisol soil with sandy loam texture, belonging to a good rye complex, class IIIb–IVa, and was replicated four times. The study showed that the productivity (seed and protein yield) of the ‘Merlin’ cultivar grown in the central-eastern part of Poland was approximately 8% higher than that of the ‘Aldana’ cultivar. The cultivation method had a relatively minor influence on soybean yield, the content of selected nutrients, morphological features, and elements of the yield structure. The soil in strip-tillage method was more compact than the soil cultivated with a plough. After harvesting soybeans at a depth of 30, and 40 cm, the compactness of soil in strip-tillage or with reduced tillage was much lower than in spring, highlighting a positive effect of soybean cultivation on loosening the arable layer.

The Application of Rain Gardens in Urban Environments: A Bibliometric Review

The increasing challenges of urbanization and climate change have driven the need for innovative stormwater management solutions. Rain gardens, as a nature-based solution (NBS), have emerged as a critical component in urban water management, particularly in enhancing hydrological regulation, water quality, and ecosystem services. This bibliometric review examines the application of rain gardens in urban environments, focusing on their roles in stormwater management, pollutant removal, and ecological enhancement. Data from 728 academic papers published between 2000 and 2023 were analyzed using the Web of Science (WoS) Core Collection, employing bibliometric tools such as the “Bibliometrix” R package and CiteSpace. The analysis highlights the increasing global interest in rain gardens, particularly since 2015, with China and the United States leading research efforts. Key findings reveal that rain gardens significantly reduce runoff, improve water quality, and contribute to urban biodiversity. In addition, their integration into public spaces offers landscape esthetics and social benefits, enhancing the quality of life in urban areas. However, challenges remain in optimizing their design for diverse climates and long-term performance. The study underscores the need for further research on plant–soil interactions, pollutant removal mechanisms, and the broader ecological and social contributions of rain gardens. This review provides insights into the evolution of rain garden research and identifies future directions for advancing sustainable urban stormwater management.

Geo-Hydrobiology and Geoinformatics Mapping of Ethnobotany in the Gandhamardan Hills, Odisha, India

Objective: The Gandhamardan Hills (GMH)range is a group of small mountains in Peninsular India in Balangir district in Odisha state in India. There is uniqueness in geology, geography, geomorphology, climatology, Hydrology, petrology, and lithology. The lithology, soil, water, geomorphology, and traditional use of plants in Ayurveda (India) have holistic medicinal/surgery. origin. Geo-hydro-biological amalgamation through Geological Information Systems (GIS) and chemical analysis is still being explored, and the present research emphasises such studies. Methods: Data about geo-hydro-biology through grapy, geology, geomorphology, hydrology, and traditional medicinal practices are implored from literature sources, using TOPO and Q-GIS maps and ERDAS software; their analytical interpretations were reported. The chemical analysis was conducted using X-ray fluorescence spectrometric studies of the water and soil of GMH, and the exuberance of ethnobotanical species in GMH was correlated. Results Laboratory analysis, literature studies, and interaction with Ayurvedic and Kaviraj practitioners, 154 popular species databases with their pharmacological applications reported for ordinary people. Many species have multidimensional applications that can transform Ayurveda into Materia medica. Conclusion: This ethnobotanical study documented the use of plants by the local community. The natural medicinal plants are cheap for the rural communities. The information gathered can be used for further scientific investigation to develop new commercial plant-based medicines as they will be safer than synthetic drugs. SDGs 1 to 3 and 12, 13, and 15 will be satisfied if we can conserve and adequately manage the hub of medicinal plants in GMH.

Biochar addition enhances remediation efficiency and rapeseed yield in copper-contaminated soil.

Soil contamination with copper (Cu) threatens ecological security and human health. Rapeseed demonstrates potential in remediating copper-contaminated soil, and biochar-assisted phytoremediation is increasingly being employed to improve remediation efficiency. However, the combined application of them has not been thoroughly studied in terms of the synergistic effects and the mechanisms of their interaction. In this regard, this study conducted a pot experiment to evaluate biochar-assisted remediation under Cu-contaminated soil with varying biochar application rates; Furthermore, the plant physiological mechanism and soil physicochemical properties involved in the biocharrapeseed system was explored. Our results showed that the exchangeable pool of copper in soil decreased by 10.0% and 12.3% with adding 5% biochar (BC1) and 10% biochar (BC2) relative to control (BC0), respectively, prior to rapeseed cultivation. The rapeseed cultivation for one season further reclaimed 4.9%, 9.0%, and 13.6% of the available copper in this soil by root extraction under the BC0, BC1, and BC2 treatments, respectively. The overall copper concentration in plants decreased by 23.7% under BC2 and 13.3% under BC1 compared to BC0. However, the plant's dry biomass at BC1 and BC2 treatments increased by 1.7-fold and 2.7-fold relative to BC0, which offset the negative impact of the decreased copper concentration on phytoremediation. Physiological analysis showed adding 10% biochar decreased the MDA content by 36% in the leaf and 49% in the root, compared to BC0. The transmission electron microscopy for cell wall ultrastructure in root tips showed that biochar addition in Cu-contaminated soil increased the mechanical strength of the celL wall, explicitly increasing the thickness of the secondary cell wall. Further cell wall components analysis revealed a remarkable increment of the pectin content in BC2 relative to BC0, increased by 56% in the leaf and 99% in the root, respectively. Additionally, 10% biochar application led to a roughly 2-fold increase in seed yield via ameliorating the soil physicochemical properties and increasing the rapeseed growth. These findings offer insights into synergistic rapeseed-biochar use for Cu-contaminated soil remediation.

Environmental Degradation Study of Polypropylene Films Incorporating Pro-Oxidants: Comprehensive Analysis and Ecotoxicological Assessment

Our research described in this paper investigated the environmental degradation of polypropylene (PP) films incorporating pro-oxidants and assessed their impact on the ecosystem. Weathering aging effects were monitored through Fourier-Transform Infrared (FTIR) analysis, revealing significant changes in carbonyl, hydroxyl and amorphous regions post-aging. The presence of pro-oxidants intensified these changes, indicating higher oxidation levels. Contact angle measurements demonstrated decreased hydrophobicity upon aging, particularly pronounced in pro-oxidant-containing films (initial contact angle: 87.79° for PP/1% Co/1% Fe, sample (F6) decreased to 79.24° after aging). Differential Scanning Calorimetric (DSC) analysis revealed decreased melting temperatures (initial Tm: 159.5 °C for F6 decreased to 148 °C after aging) and the crystallinity post-aging (initial χ: 73.25% for F6 decreased to 60.17% after aging), suggesting increased susceptibility to degradation. Thermogravimetric Analysis (TGA) showed decreased thermal stability after aging, especially in PP/pro-oxidant films; the Tonset (T5); 432.00 °C for F6, decreased to 268.00 °C after aging; where Tonset is the temperature corresponding to 5% weight loss. Biodegradation tests indicated enhanced biodegradability in the pro-oxidant-containing films, with cobalt and ferrous stearate mixtures showing the highest degradation degrees (e.g., PP/1% Co/1% Fe: ≈ 77% biodegradation after 140 days). Ecotoxicological evaluations, including microbial toxicity and plant germination and growth tests, revealed no inhibitory effects of the degradation products on soil flora or plant growth, confirming their nontoxic nature. Overall, we believe this comprehensive study provides insights into the environmental fate of PP films with pro-oxidants, highlighting their potential for accelerated degradation without adverse ecological impacts.

Soil metabolic disturbance drives replant disease (intraspecific negative plant–soil feedback): Insights from an experiment examining soil impacts up to 20 years after a ginseng crop

Replant diseases (RDs), intraspecificnegativeplant–soilfeedback, often stem from nutrient deficiency, allelopathy, or pathogen accumulation. However, the RDs of certain crops are long-lasting and their causes remain unknown. We examined Panax quinquefolius RD in a space-for-time soil sequence representing crop rotation restoration over 1, 10, and 20 years using multiomics and bioassays. Compared with the soils with no ginseng cultivation history, we found 110 significant potential factors related to RD, surprisingly, 53 of which remained unrestored after 20 years. Soil pH and the levels of organic nutrients (amino acids, carbohydrates, and alditols), allelopathic-promoting metabolites (phenolic acids, amines, pyridines, etc.), and beneficial bacteria (Sphingomonas, Burkholderia-Caballeronia-Paraburkholderia, and Terrabacter) and fungi (Acremonium, Penicillium, and Naganishia) decreased, while the levels of allelochemicals (pyruvic and fatty acids) increased. The expression of all metabolic pathways was significantly down-regulated, with the exception of the up-regulated fatty acid-related metabolic pathways. We confirmed that decreased organic nutrient levels and increased levels of allelochemicals impaired P. quinquefolius growth. Soil metabolic factors rather than microbial factors were dominant by network analysis. In conclusion, we found that the overall changes in nutrient levels and metabolic and microbial factors contributed to short-term RD (1–10 year) persistence, whereas long-term RD (after 20 years) primarily resulted from disordered soil metabolite levels and pathways. This research will help deepen our understanding of the relationship between RD and potential changes in the factors influencing RD that are caused by soil legacy effects of valuable plants and provide theoretical guidance for effective soil quality improvement.

Study on the Changes in the Microbial Community in Rhizosphere Soil of Blueberry Plants at Different Growth Stages

In order to clarify the relationship between mineral nutrients and rhizosphere microorganisms at different growth and development stages of blueberry (Vaccinium spp.), this work studied the dynamic changes in element content and microbial quantity in different parts of blueberry plants. The test material was a 12-year-old half-highbush blueberry variety (‘Beilu’). The changes in the mineral nutrient elements in leaves, branches and the soil of blueberry plants were studied at the full bloom stage (T1), green fruit stage (T2), mature stage (T3) and late mature stage (T4), and the correlations of the average contents of mineral elements in the four periods were studied. The bacterial community in the rhizosphere soil was determined and analyzed using 16S rRNA high-throughput sequencing technology. The results showed that the changes in other mineral elements in various parts of blueberry plants varied in different periods. Nitrogen (N) showed a downward trend in branches, leaves and soil, especially in leaves (p < 0.05). The N contents in T2, T3 and T4 decreased by 9.9%, 26.4% and 29.9%, respectively. The N contents in the leaves and branches showed a downward trend at different growth stages, especially in leaves. The phosphorus (P) content in leaves showed a trend of increasing first and then decreasing, while it continued to increase in branches. The content of potassium (K) in leaves changed significantly, where it increased first and then decreased. The content of calcium (Ca) in leaves decreased first and then increased, while the content of magnesium (Mg) in branches and leaves decreased first and then increased, and the relative change was significant. The contents of iron (Fe) and zinc (Zn) in leaves decreased first and then increased, while the contents of manganese (Mn) and copper (Cu) were relatively stable. Cu decreased first and then increased in leaves and soil, and it increased first and then decreased in branches. The mineral nutrients in different growth stages of blueberry showed significant correlation in leaves, branches and soil. Mn in leaves was significantly positively correlated with P, Ca, Mg, Mn, Cu and Zn in soil (p < 0.01). Nitrogen and calcium in leaves were significantly correlated with manganese and phosphorus in soil, respectively. Ca in branches was significantly positively correlated with N and K in soil and was significantly positively correlated with Zn in soil (p < 0.01). Magnesium was significantly negatively correlated with iron in soil. The bacterial community structure of the blueberry rhizosphere soil changed significantly over time (p < 0.05), and the relative abundance showed the following trend: T4 > T2 > T3 > T1. At the phylum level, Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi and Verrucomicrobia were the dominant bacteria in different periods. Candidatus solibacter and Bryobacter were significantly higher in T1 and T3 than in T1 and T4. Bradyrhizobium flora increased significantly at T3. Sphingomonas increased significantly at T1 (p < 0.05).

Revealing the characteristics of myxobacterial communities in rhizosphere and non-rhizosphere soils of halophytic plants following wetland degradation using high-throughput sequencing

Myxobacteria represent a distinct group in soil microbial communities, with their predatory capabilities playing a vital role in regulating and stabilizing these communities. However, the characteristics of myxobacterial communities in the soils of Karelinia caspia (KC), a halophytic plant growing in degraded wetlands, remain unclear. In this study, we investigated myxobacterial communities in rhizosphere and non-rhizosphere soils from nine KC’ sampling sites in saline-alkaline land formed after wetland degradation using high-throughput sequencing. A total of 486 myxobacterial ASVs were identified from both rhizosphere and non-rhizosphere soil samples, comprising 2.68% of the total bacterial community. The dominant genera at the genus level were Unclassified_g_bacteriap25 and Haliangium. FAPROTAX functional predictions indicated that myxobacteria in rhizosphere soils performed various ecological functions, such as predation, organic matter decomposition, and cellulose degradation, while in non-rhizosphere soils, they primarily displayed predatory functions. The high proportion of unclassified functions suggests that many aspects of myxobacteria in soil remain unexplored. Correlation analysis showed that electrical conductivity, soil moisture, and total nitrogen significantly affected myxobacterial diversity and abundance. Co-occurrence network analysis revealed multiple associations between myxobacteria and other bacterial groups, highlighting their crucial role in maintaining the dynamic equilibrium of soil bacterial communities. These findings deepen our understanding of the relationship between microbial community dynamics and environmental factors, laying a strong foundation for future research in soil microbial ecology and conservation strategies.

Stronger increase of methane emissions from coastal wetlands by non‐native Spartina alterniflora than non‐native Phragmites australis

Societal Impact StatementThe invasive species S. alterniflora and P. australis are fast growing coastal wetland plants sequestering large amounts of carbon in the soil and protect coastlines against erosion and storm surges. In this global analysis, we found that Spartina and Phragmites increase methane but not nitrous oxide emissions, with Phragmites having a lesser effect. The impact of the invasive species on emissions differed greatly among different types of native plant groups, providing valuable information to managers and policymakers during coastal wetland planning and restoration efforts. Further, our estimated net emissions per wetland plant group facilitate regional and national blue carbon estimates.Summary Globally, Spartina alterniflora and Phragmites australis are among the most pervasive invasive plants in coastal wetland ecosystems. Both species sequester large amounts of atmospheric carbon dioxide (CO2) and biogenic carbon in soils but also support production and emission of methane (CH4). In this study, we investigated the magnitude of their net greenhouse gas (GHG) release from invaded and non‐invaded habitats. We conducted a meta‐analysis of GHG fluxes associated with these two species and related soil carbon content and plant biomass in invaded coastal wetlands. Our results show that both invasive species increase CH4 fluxes compared to uninvaded coastal wetlands, but they do not significantly affect CO2 and N2O fluxes. The magnitude of emissions from Spartina and Phragmites differs among native habitats. GHG fluxes, soil carbon and plant biomass of Spartina‐invaded habitats were highest compared to uninvaded mudflats and succulent forb‐dominated wetlands, while being lower compared to uninvaded mangroves (except for CH4). This meta‐analysis highlights the important role of individual plant traits as drivers of change by invasive species on plant‐mediated carbon cycles.

Performance evaluation of waste phosphogypsum-based solidified sludge: From laboratory test to field application

Massive dredged sludge is being landfilled without effective use due to its high-water content and poor engineering properties, which not only leads to soil resources waste, but also occupies a large amounts of land sources. In this study, ternary stabilizer, including waste phosphogypsum (PG), ground granulated blast-furnace slag (GGBS), and lime (LM) with a mixing proportion of PG: GGBS: LM = 35:60:5, was adopted to improve the mechanical and environmental behaviors of sludge for subgrade filling purpose. The initial water content of sludge was controlled using two different dehydration methods for comparison. A series of laboratory tests, including unconfined compressive strength (UCS), organic matter content, and pH value were tested to understand its physical-mechanical properties. Thereafter, field application model equipped with a mini weather monitoring station was constructed to monitor the influence of solidified matrix on the surrounding water and soil environment. Time -dependent parameters such as plant growth, temperature, humidity, total nitrogen, phosphorus/potassium content, electrical conductivity, and pH value were monitored. Results indicate that the incorporation of PG-GGBS-LM ternary stabilizer significantly improves the mechanical and environmental properties of dredged sludge. The optimal dosage of the ternary stabilizer is 36%, which can result in a UCS value of the 2.0 MPa (slightly higher than ordinary Portland cement) after 28 days of curing. Field application reveals that plants could grow normally in solidified sludge. The environmental related parameters (i.e., total nitrogen, phosphorus/potassium content, electrical conductivity, and pH value) were similar with those in conventional planting soil, suggesting the advantage of the proposed PG-GGBS-LM ternary stabilizer in mechanical, economic and environmental aspects.

Impact of Biochar and Water Regimes on Arsenic Transfer and Uptake in Rice: Insights into Transporter Behaviour and Soil–Plant Dynamics

Impact of Biochar and Water Regimes on Arsenic Transfer and Uptake in Rice: Insights into Transporter Behaviour and Soil–Plant Dynamics

Impacts of plastic pollution on soil–plant properties and greenhouse gas emissions in wetlands: A meta-analysis

Plastic pollution in wetlands has recently emerged as an urgent environmental problem. However, the impacts of plastic contamination on soil-plant properties and greenhouse gas (GHG) emissions in wetlands remain unclear. Thus, this study conducted a meta-analysis based on 44 study sites to explore the influence of plastic pollution on soil physicochemical variables, soil microorganisms, enzyme activity, functional genes, plant characteristics, and GHG emissions (CO2, CH4, and N2O) in different wetland types. Based on the collected dataset, the plastic pollution significantly increased soil organic matter and organic carbon by on average 28.9 % and 34.2 %, respectively, while decreased inorganic nutrient elements, bacteria alpha diversity and enzyme activities by an average of 5.9 −14.2 %. The response of bacterial abundance to plastic pollution varied depending on phylum classes. Plant biomass and photosynthetic efficiency were decreased by an average of 12.8 % and 18.4 % due to plastic pollution. The concentration and exposure time of plastics play a key role in influencing the soil and plant properties in wetlands. Furthermore, plastic exposure notably increased the abundance of the functional genes related to C degradation and the ammonia oxidizing microorganisms, and the consequent CO2 and N2O emissions (with effect sizes of 2.10 and 1.94, respectively). We also found that plastic concentrations and exposure duration affected the wetland soil–plant system. Our results might be helpful to design further investigations on plastic effects and develop appropriate measures for mitigating plastic pollution in wetlands.

Enhancing tomato growth and soil fertility under salinity stress using halotolerant plant growth-promoting rhizobacteria

Soil salinization is a critical issue that not only hampers the efficiency and sustainability of global agricultural production but also poses significant challenges to the achievement of sustainable development goals across environmental, economic, and social dimensions. Halotolerant plant growth-promoting rhizobacteria (HPGPR) have the potential to mitigate abiotic stress, foster plant growth, and bolster the stress resistance capabilities of crops. This study conducted the isolation, identification, and characterization of HPGPR originating from a saline-alkali orchard area in northwest China. The efficacy of the isolated bacterial strains was evaluated through potted plant experiments, assessing the growth of tomato plants under in vitro conditions and under varying salinity stress. Ultimately, the study investigated the influence of these HPGPR on soil physicochemical properties, enzymatic activities, and the structure and composition of the microbial community. Upon isolating 12 bacterial strains, we conducted an in vitro assessment of their salt tolerance, ultimately singling out three robust isolates, which exhibited exceptional salt tolerance. Detailed 16S rRNA gene sequencing and meticulous taxonomic evaluation systematically assigned these isolates to Priestia endophyticus GSCK1 (accession number: OR569048), Bacillus atrophaeus GSCK2 (accession number: OR569061), and Serratia fonticola GSCK6 (accession number: OR569062), respectively. These strains exhibited notable biochemical and plant growth-promoting traits, including enzymatic activities and the production of indole-3-acetic acid. They significantly enhanced plant growth metrics and soil fertilities, particularly strain GSCK6, which also reshaped the soil microbial community, augmenting beneficial microbe abundance. The HPGPR treatment notably improved soil pH, nutrient availability, enzymatic activities, and reduced soil electrical conductivity, underscoring their potential in agricultural resilience against salinity. The eco-friendly salt stress mitigation strategy of HPGPR not only enhances soil quality and promotes plant growth by regulating the composition and function of microbial communities, but also provides a novel solution for global agricultural production. This approach is conducive to increasing crop yield and quality, reducing the limitations of saline-alkali land on agricultural production, and promoting food security and sustainable agricultural development.

Context dependence of grassland plant response to arbuscular mycorrhizal fungi: The influence of plant successional status and soil resources

Abstract Many of the disturbance‐sensitive, late successional plant species in grasslands respond to arbuscular mycorrhizal (AM) fungi more positively via growth and establishment than plants that readily establish in disturbed areas (i.e. early successional species). Inoculation with AM fungi can therefore aid the establishment of late successional species in disturbed areas. If the differential benefit of AM fungi to late versus early successional plants is context‐dependent, however, this advantage could be diminished in high phosphorus (P) post‐agricultural soils or in future climates with altered precipitation. In this greenhouse experiment, we tested if late successional plant species are less plastic in their reliance on AM fungi than early successional plants by growing 17 plant species of different successional status (9 early and 8 late successional) in full factorial combinations of inoculated or uninoculated with AM fungi, with ambient or high P levels, and with low or high levels of water. AM fungi positively affected the biomass of the 17 grassland plant species, but across all environments, late successional plant species generally responded more positively to AM fungi than early successional plants species. AM fungal growth promotion and change in below‐ground biomass allocation was generally diminished with P fertilizer across all plant species, and while there was significant variation among plant species in the sensitivity of AM fungal responsiveness to P fertilization, this differential sensitivity was not predicted by plant successional status. The role of AM fungi in plant growth promotion was not generally altered by variation in watering, however late successional plant species allocated a greater proportion of their biomass below‐ground in response to AM fungi in low versus high water conditions. Synthesis. Overall greater responsiveness to arbuscular mycorrhizal (AM) fungi by late successional species is consistent with an important role of AM fungi in plant succession, even while AM fungi are less impactful overall in high P soils. However, the increase in responsiveness of below‐ground allocation of late successional species to AM fungi in low water conditions suggests that successional dynamics may be more dependent on AM fungi in future climates that feature greater propensity for drought.