Abstract:【Objective】High-throughput sequencing technology was used to study the changes in the diversity of culturable phosphorus-solubilizing bacteria (PSB) during serial enrichment, to evaluate the effects of different media and generations on diversity assessment of culturable PSB in paddy soil.【Methods】Through serial passages with inorganic phosphorus medium (IPM) and organic phosphorus medium (OPM) in both solid and liquid forms, culturable "potential" PSB enrichments were obtained from the first (1st-En), second (2nd-En) and third (3rd-En) generation of the media and then for DNA extraction together with the tested soil. Bacterial 16S rRNA genes were analyzed by high-throughput sequencing technology to explore the enrichment laws of soil culturable "potential" PSB and their proportions to soil background indigenous bacterial community.【Results】The results showed that a total of 58 phyla, 160 classes, 373 orders, 575 families and 979 genera were detected in soil background bacterial communities, and 20 phyla, 35 orders, 80 orders, 121 families and 223 genera of the "potential" PSB were cultured by four media after three generations. The diversity of culturable "potential" PSB was generally higher in OPM than IPM and the proportions of culturable "potential" PSB in soil background indigenous bacterial community were the highest at the phylum level (8.62%~25.9%), while only 3.22%~12.5% at other taxonomic levels. Compared with the database of "the known PSB" constructed in this study, 110 genera of "the known PSB" existed in soil background indigenous bacterial community; 83 genera of "the known PSB" were existed in the enrichments of four media after three consecutive generations and accounting for 75.5% of "the known PSB" in the background soil. Thus, at least about 24.5% of the genera of "the known PSB" in the soil were not enriched or omitted. During the culture of three generations with different media, the culturable dominant PSB mainly included Proteobacteria, Actinobacteriota and Firmicutes, and their relative abundance reached a total of 97.20~99.97%; at the genus level, PSB with different physiological and metabolic characteristics was enriched by different media and generations. In addition, a large number of 140 genera were also enriched in which phosphorus-dissolving function or characteristic genes were not demonstrated, accounting for 62.8% of soil culturable "potential" PSB communities. Most of the above genera were rare with relatively low abundance, but a few have growth advantages, such as Chelatococcus.【Conclusion】Combining the high-throughput sequencing technology with the traditional microbial culture technology, our study reveals that the diversity of soil culturable PSB can be strongly affected by the components and status of culture medium and the generations, which provides a reference for the directional exploration and research of environmental PSB resources.

Abstract:【Objective】 Long-term tillage and fertilization accelerate soil acidification of red loam rice. Thus, this study was designed to study the effects of green manure, straw return, and lime combination on the soil acidity characteristics of rice soil and rice yield. 【Method】This study is based on the long-term positioning micro-area experiment started in 2016 to explore the effects of no fertilization (CK), chemical fertilizer (F), chemical fertilizer + milk vetch + rice straw return (GRF), chemical fertilizer + milk vetch + straw return (GRFL) treatment on rice yield and different forms of acid in red soil. The effects of soil salt-based ions and soil acid-base buffer capacity was resolved, and the correlation between soil acid-base buffer capacity, exchangeable acid, organic matter, and exchangeable salt-based ions was investigated. 【Result】 The results for seven consecutive years showed that compared with F treatment, the yield of early and late rice treated by GRF increased by 19.9% and 5.1%, respectively, and the average yield increase rate in 7 years was 12.8% and 5.9%, respectively. The yield of early and late rice treated by GRFL increased by 23.4% and 14.2%, respectively, and the average yield increase rate in 7 years was 11.1% and 8.9%, respectively. During this time, the soil pH of early and late rice treated with CK, F and GRF showed a decreasing trend year by year, while the soil pH value of GRFL treatment showed a trend of first increasing and then decreasing. Compared with F treatment, GRF and GRFL treatment significantly improved the exchangeable K, the total amount of exchangeable salt-based ions and the acid-base buffer capacity of early and late rice soil, and there was no significant difference between GRF and GRFL treatments, but all indexes of GRFL treatment showed an improvement trend. Correlation analysis showed that pH was negatively correlated with exchangeable acidity and exchangeable H+ (P < 0.01) and positively correlated with acid-base buffer capacity, exchangeable Na+, exchangeable Mg2+, and the total amount of exchangeable salt group ions (P < 0.01). Also, the soil acid-base buffer capacity was mainly related to the exchangeable acidity, exchangeable H+, exchangeable Na+ and exchangeable Mg2+. In addition, rice yield was related to soil acidity properties and nutrient effects, and the soil acidity properties had the greatest impact. 【Conclusion】 The results showed that rolling green manure and straw returning to the field could effectively alleviate the acidification of paddy soil and improve rice yield, and the addition of lime could enhance its effect, and the exchangeable acidity, exchangeable H+, acid-base buffer capacity, exchangeable Na+, exchangeable Mg2+, and total exchangeable salt-based ions were the main factors affecting soil pH.

Abstract:【Objective】This study aimed to clarify the general rules of the impact of grazing on the composition and function of soil fungal communities in northern grasslands of China, and to provide the theoretical foundation for ecological conservation efforts in these grasslands. 【Method】This study collected 119 raw data of soil fungi from different studies in grazed grasslands, used unified bioinformatics processing methods and meta-analysis to demonstrate the changes in α-diversity, community composition and functional groups of soil fungi within grazed grasslands, and used weighted mixed-effects models for environmental factor analysis. 【Result】The results indicated that grazing reduced the soil fungal α-diversity and significantly decreased the relative abundance of pathotrophic fungi, wood saprotrophic fungi, soil saprotrophic fungi, and endophytic fungi. The change in grazing soil fungal α-diversity and functional fungal relative abundance depended on altered environmental factors in different regions. The negative effect of grazing on soil fungal α-diversity was mitigated to some extent in the regions with lower organic carbon content, lower carbon-to-nitrogen ratio, and higher annual precipitation. Initial soil organic carbon content and grazing exclusion duration influenced the variations in functional fungal abundance, with long-term grazing exclusion promoting the recovery of soil saprotrophic and symbiotrophic fungi communities. As the initial carbon-to-nitrogen ratio increased, the degree of reduction in the relative abundance of pathotrophic fungi under grazing decreased. In contrast, the degree of reduction in the relative abundance of saprotrophic fungi increased. Importantly, in regions with lower precipitation, grazing had a more significant impact on reducing the relative abundance of saprotrophic and symbiotrophic fungi. 【Conclusion】Overall, grazing negatively affected the α-diversity and functional traits of soil fungal communities in the northern grasslands of China. However, the degree and direction of this effect depended on the local environmental conditions.

Abstract:【Objective】Soil pH is a crucial indicator of arable land quality. Therefore, precise and rapid measurement of soil pH is essential for the implementation of digital agriculture. 【Method】In the present study, pH levels of the black soil in the Liaohe and Songnen plains were determined in situ using a self-developed portable soil multi-parameter rapid detection instrument (SHMI2000). The results were compared to those obtained in the laboratory using the potentiometry method (HJ 962–2018). 【Result】(1) The laboratory observations showed that surface and subsurface soil pH values ranged from 4.04 to 10.09, and 4.01 to 10.06, respectively. The mean values were 6.13 and 6.47, and the variation coefficient values were moderate at 19.64% and 18.37%, respectively. Also, the study also revealed that the soils in the southwest black soil area were predominantly alkaline, whereas the soils in the east (Sanjiang Plain), north (Songnen Plain), and south (particularly in the Southern Heilongjiang, Jilin, and Liaoning Provinces) were acidic in nature. (2) The Pearson correlation analysis showed a strong relationship (correlation coefficient of 0.81, P=9.11×10-52) between pH values obtained in situ and the laboratory. (3) The correlation coefficient increased to 0.93 after the moving average process, using 0.2 pH units as step size.【Conclusion】Therefore, the SHMI2000 instrument can accurately and reliably acquire black soil pH values in situ.

Abstract:【Objective】Flooding and organic matter addition to anaerobic treatment has been proven to reduce excess salt in greenhouse soil and improve soil quality. There are many types of organic matter in the field, so how to select effective materials is a key problem. 【Method】Six types of organic materials with different carbon (C), nitrogen (N) and sulfur (S) proportions were selected and tested at two rates of 2 g·kg?1and 8 g·kg?1. 【Result】Flooding and organic matter addition can quickly create a reducing environment for soil. On the first day of incubation, the redox potential (Eh) rapidly decreased to around 0 mV, accompanied by a rapid decline in soil electrical conductivity (EC), SO42?, and NO3??N. By the end of the anaerobic cultivation process, almost all NO3??N had been removed, and the variety and amount of organic matter added had no significant effect on NO3??N removal. The effect of rapeseed straw with low C/S ratio on SO42? removal was weak, with a removal rate of 58%. A high C/S ratio maize straw can reduce SO42? from an initial concentration of 153 mg·kg?1 to 17 mg·kg?1, a decrease of 89%. Different amounts of added materials only affect the speed of SO42? removal, but not the final removal effect. At the end of cultivation, there was no significant difference in SO42? removal between treatments with 2 g·kg?1 and 8 g·kg?1 of organic matter added. The content of other forms of sulfur did not change significantly, indicating that most of the reduced SO42? was converted into organic sulfur. 【Conclusion】For the purpose of remediating excess SO42? in soil, it is recommended to use organic materials with high C/S such as maize straw and set the addition amount at 2 g·kg?1 to obtain good results.

Abstract:【Objective】Long-term tillage measures can significantly change the distribution of soil aggregates, microbial abundance, and total nitrogen storage in farmland. However, whether there is a correlation between these properties remains unclear. This study aimed to reveal the relationship between total nitrogen content and nitrogen functional microorganisms within different particle sizes aggregates under long-term conservation tillage in dry farming areas of the Loess Plateau.【Method】Based on the 10-year (2009-2020) long-term tillage experiment (conventional tillage: plow tillage, PT; conservation tillage: chisel plow tillage, CPT and zero tillage, ZT), the effects of long-term conservation tillage on the distribution of total nitrogen and its relationship with the abundance of functional genes (amoA-AOA, amoA-AOB, nirS, nirK, nosZI and nosZII ) within aggregates in dry farmland were studied.【Result】Long-term conservation tillage (CPT and ZT) significantly increased the mass percentage of mega-aggregates (> 2 mm ) and macro-aggregates (0.25 ~ 2 mm), while it decreased the mass percentage of micro-aggregates (< 0.25 mm). Compared with PT, long-term CPT and ZT treatments significantly decreased the soil nitrogen mineralization rate, nitrification potential, and denitrification potential but increased the total nitrogen content in the 0~20 cm soil layer by 53.4 % and 49.9 %, respectively. The total nitrogen contribution rate of macro-aggregates of CPT and ZT treatments increased by 16.2 % and 21.8 %, respectively. Using qPCR technology, it was found that CPT and ZT significantly increased the abundance of bacteria, fungi, and nitrogen functional genes (except amoA-AOB); and the abundance of fungi, nirS, and nosZI in macroaggregates was significantly higher than that in microaggregates and macroaggregates, while the abundance of nosZII gene showed the opposite trend. Mantel analysis showed that aggregate size, soil texture, mineral nitrogen content, sucrase activity, and urease activity were the key factors regulating the abundance of nitrogen-functional microorganisms within aggregates. Correlation analysis showed that the total nitrogen content in aggregate soil was positively correlated with MBN, DON, and the abundance of bacteria, fungi, amoA-AOB, and nosZII genes, while negatively correlated with the abundance of nirS and nirK denitrification genes. 【Conclusion】Long-term conservation tillage can increase soil total nitrogen storage mainly by increasing the contribution rate of nitrogen in macro-aggregates. As the abundance of bacteria, fungi, and nitrification process genes in macroaggregates increases, the abundance of nirS and nirK denitrifying microorganisms decreases, which improves the trend of the nitrogen cycle and significantly increases soil total nitrogen content.

Abstract:【Objectives】Rhizosphere microorganisms affect the availability and transformation of soil nutrients, which are closely related to the growth and health of plants. Changes in rhizosphere microorganisms with plantation years of Fructus aurantii were studied for better field F. aurantii management. 【Methods】The rhizosphere soil samples of F. aurantii planted for 4 (Y4), 20 (Y20), and 40 (Y40) years in Chongqing were collected on 2020. The changes in diversity index and community composition structure of bacteria and fungi were analyzed by high-throughput sequencing technology, and the correlation between rhizosphere microbial community composition (bacteria and fungal) and soil properties was explored.【Results】Soil organic matter (SOM), total nitrogen (TN), available N (AN), available phosphorus (AP) and available potassium (AK), except pH, were significantly higher (P < 0.05) in Y40 than those under Y4 and Y20. The Shannon and Pielou indices of fungi were significantly increased with the increase in plantation age (P < 0.05), while those of bacteria had no significant changes. The principal coordinate analysis (PCoA) indicated that the rhizosphere bacterial and fungal community structures under Y40 significantly differed from those under Y4 and Y20. At the phylum level, the dominant bacteria phyla were Proteobacteria, Acidobacteria, Actinobacteria and Gemmatimonadetes, and their total relative abundance accounted for 61.07~87.79%. Also the dominant fungal phyla were Ascomycota and Basidiomycota which accounted for 64.70-85.75%. At the genus level, the abundance of beneficial bacteria and fungi in rhizosphere soil under Y40 was significantly lower than those under Y4 (P < 0.05). For example, the abundance of Sphingomonas, Ochrobactrum, Nocardioides, Pseudomonas, Trichosporon and Chaetomium were decreased by 51.21%, 91.32%, 78.60%, 81.87%, 70.58% and 60.74%, respectively. Furthermore, the abundance of pathogenic genera including Fusarium, Plectosphaerella and Ilyonectria, were significantly increased by 117.6%, 323.9% and 1631% under Y40 compared to Y4 (P < 0.05), respectively. The mantel analysis showed that soil pH and nutrient availability were the important abiotic factors influencing the composition of bacterial and fungal communities under different F. Aurantii planation years. 【Conclusions】 Long-term plantation of F. Aurantii altered soil bacterial and fungal community structures. Specifically, the fungal diversity index and the abundance of pathogenic fungi increased, while the abundance of beneficial microbes in the rhizosphere soil decreased. These alterations were the main reasons for inducing an aggravation of the related disease and then a worse plant growth with the increasing age of F. Aurantii plantation.

Abstract:【Objective】Viruses are the most abundant and diverse group of microorganisms on Earth as they can be found in a wide range of organisms and environments. Despite their ubiquity, there are relatively few studies on the virome in paddy soil systems, which is an area that warrants investigation. 【Method】In this study, virus sequences were mined from rice soil macrogenome sequencing data in public databases and characterized. 【Result】A database of paddy soil viruses (PSVD) was constructed, which contained 8,791 viral operational taxonomic units (vOTUs) and 168,940 protein sequences. In PSVD, 31.41% of the sequences could predict the taxonomic status of the species. These viral sequences belonged to 76 known virus families, with the majority of viruses coming from the Caudoviricetes, and their hosts were mainly distributed across 11 bacterial phyla. Also, Auxiliary Metabolic Genes (AMGs) carried by rice field soil viruses were analyzed, and 39 carbohydrate-active enzymes (CAZymes) genes, which may have been widely distributed in rice soil systems, were identified, and the presence of these genes contributed to biogeochemical cycling. 【Conclusion】In summary, this study innovatively constructed a PSVD database and used DRAM-v to mine AMG genes in paddy soil systems, thus, laying a research foundation for later studies of paddy soil virus groups and providing new insights for the resolution of paddy virus communities.

Abstract:【Objective】There are many factors governing the migration of non-aqueous phase liquids (NAPLs) in the subsurface because of the simultaneous flow of immiscible phases in a multiphase system including NAPLs, water and air after the leakage of NAPLs. The driving mechanism of NAPLs in the site soil-water system is complex, and predicting and visualizing the spatial-temporal distribution and changes of pollutants are prerequisites for scientific and standardized green and low-carbon remediation and control of soil and groundwater pollution. 【Method】This article is based on the WebGIS geographic information system platform and incorporates self-developed organic contamination multiphase flow-temperature-chemical multi-field coupled simulation and Cesium visualization technology. It integrates a Browser/Server (B/S) architecture-based spatial distribution simulation and visualization system for organic pollutants in the soil-water system of contaminated sites.【Result】The visualization system can be applied to the integrated management of organic pollution site investigation and monitoring data, graphical modeling of organic pollution spatiotemporal distribution, and visual expression of the entire multi-field coupling pollution process. The system is applied to characterize the spatiotemporal distribution and variation of the di-(2-Ethylhexyl) Phthalate (DEHP) contaminant in the soil and groundwater of a certain organic pollution site in the South. The overall fit of the system reaches an R-value of 0.91, with simulation errors less than 30%. Based on the coupling model, the system further predicts the attenuation process of DEHP. It calculates the proportions of NAPL that remain adsorbed as a residual phase (50.3%) and those that undergo degradation due to volatilization (11.3%) and dissolution (7.4%) within the simulation period. 【Conclusion】Due to difficulties in acquiring on-site parameters, the model used physical and chemical properties of soil, water, gas, and NAPLs referenced from relevant literature, resulting in some uncertainty in the simulation results at the site scale. Nevertheless, the overall trend of predicting the spatiotemporal distribution of DEHP is reasonable and aligns with the coupled mechanisms of multi-phase flow, temperature field, and chemical field in organic pollution sites. Through visualizing different scenarios of organic pollutant spatiotemporal distribution and prediction, the visualization system can provide an information platform for organic pollution risk assessment, precise prevention and control, and comprehensive management of contaminated sites.

Abstract:Soil aggregates are the basic unit of soil structure and the particle size distribution of surface aggregates play an important role in soil structure and erosion process development.【Objective】Therefore, the purpose of this study was to explores the mutual transformation of soil aggregates of different particle sizes and the sediment migration path during the interrill erosion and quantify the source characteristics of eroded sediment.【Method】In this study, a quaternary red clay was collected from Xian’ning in Hubei Province of China, and the soil aggregates were labeled by the rare earth tracer method. Under the condition of 90 mm·h-1 rainfall intensity, the laboratory simulated rainfall experiment was conducted based on a miniature soil trough with the slope set at 10°. Sediment samples were collected at an interval of 6 min after steady flow production during rainfall, and the contents of rare earth elements in the samples were determined by ICP-MS. A quantitative characterization was also performed on the transformation of soil aggregates within different particle sizes(5~2 mm, large macroaggregates; 2~0.25 mm, small macroaggregates; 0.25~0.053 mm, microaggregates; and <0.053 mm, silt and clay fractions) and the source characteristics of erosion sediment under the Rare Earth Element (REE) concentration.【Result】The results show that the eroded sediment particles were mainly formed by the same size aggregates transported by runoff, and the content of the sediment particles with the increase of rainfall time. The residual aggregates showed an obvious turnover process and the aggregates with size < 0.25 mm were more easily adsorbed to the aggregates with large size, while the aggregates with size ? 0.25 mm tended to be broken (the fragmentation rate reached 45.8% and 43.3%), and the broken degree of soil aggregates increased continuously. The characteristics of sediment yield were closely related to the change in topsoil structure and sediment migration and the sediment content of < 0.053 mm and 2~0.25 mm and the contribution rate of the corresponding aggregates in sediment played an important role in the fractal dimension of runoff coefficient and sediment particle size.For the characteristics of erosion sediment production, the sediment content of < 0.053 m and 2~0.25 mm and the contribution rate of the corresponding aggregates in the sediment played an important role in the runoff coefficient and the fractal dimension of sediment particle size.【Conclusion】Thus, the change of soil topsoil structure and the characteristics of sediment loss during interrill erosion are closely related to aggregate particle size. This further deepens the dynamic process of the interrill erosion and provides a theoretical basis for the soil erosion model and soil and water conservation measures.

Abstract:【Objtctive】Tropospheric ozone (O3) is one of the most severe plant toxic air pollutants, it poses a serious threat to food production and security. Ethylenediurea (EDU) can effectively mitigate O3-induced crop yield loss. However the effects of elevated O3, EDU, and their interaction on the rhizospheric bacterial community of wheat plant remains unclear.【Method】Triticum aestivum L Nongmai88 was grown in China O3 Free-Air Concentration Enrichment (O3-FACE) platform under either ambient atmospheric O3 (A treatment) or 1.5 times ambient atmospheric O3 (E treatment), and the foliage sprayed with 450 mg·L-1 EDU or equal mount of water every ten days. The rhizospheric bacterial communitites under different treatments were analyzed by MiSeq sequencing of bacterial 16S rRNA genes in combination with redundancy analysis (RDA).【Result】It was found that EDU increased wheat root biomass by 8%~58% and decreased soil pH by 4%~10%, both of which reached significant levels under A treatment. The elevated O3, EDU foliar spray, and their interaction did not significantly affect the alpha diversity indices of rhizospheric bacterial communities, but the elevated O3 caused significant variation in the whole bacterial community structure. In addition, the effect of EDU on the structure of the bacterial community in A treatment was more significant than that under E treatment. Proteobacteria (with a relative abundance ratio of 28%~39%), Bacteroidota (11%~20%), and Acidobacteriota (7%~11%) were the most dominant phyla in all treatments of the rhizosphere soil. Both the elevated O3 and EDU foliar spray significantly reduced the relative abundance of Alphaproteobacteria but increased the relative abundance of Chloroflexi. E treatment increased the relative abundance of Nitrospirota by 71% to 164%, while EDU treatment increased the relative abundance of Planctomycota by 23% to 70%. Based on the results of RDA, it was found that the content of available postassium (AK) and pH were the main drivers, explaining 21% and 16% of the variation in bacterial community structure, respectively (P<0.005). Furthermore, the Spearman correlation analysis results showed that the content of AK in rhizospheric soil was significantly negatively correlated with the relative abundance of the Chloroflexi and Nitrospirota phyla (r=-0.846 ~ -0.586), while it was significantly positively correlated with the relative abundance of the Alphaproteobacteria subphyla (r=0.604).【Conclusion】In summary, wheat may improve its adaptability to increased O3 concentration by reducing the abundance of copiotrophic bacteria and increasing the relative abundance of oligotrophic bacteria, while foliar spraying with EDU may also alleviate wheat O3 stress in wheat through this way.

Abstract:【Objective】Soil structure is the physical framework for various processes in soils and is of great importance for quantitative studies of soil physical, chemical and biochemical processes. Existing methods for quantifying soil structure are overly dependent on laboratory techniques, resulting in them being limited by factors such as sample size, resolution and cost. 【Method】To overcome these limitations, this study utilizes digital imaging techniques to quantify ped shapes using high-resolution soil profile images. 【Result】The results show that typical structural classifications and subjective descriptions can be transformed into quantitative morphometric (circularity, roundness, major-axis ellipse angle,aspect ratio, solidtity, width-to-height ratio) data.Also, the average circularity, roundness, and width-to-height ratio of ped in the topsoil layer in the nine soil profiles (0.79, 0.74, and 1.05) were higher than those in the heart soil layer and the parent soil layer (0.64, 0.68, and 0.94), and their average aspect ratio and major-axis ellipse angle (1.35 and 42.73) were lower than those of the heart soil and parent material layers (1.79 and 49.33).【Conclusion】Therefore, the use of digital imaging techniques can accurately quantify and visually characterize the morphology of ped shape, and the technology elucidates the law that the shape of ped gradually transforms from blocky structure to granular structure in the process of soil formation.

Abstract:【Objective】Economical crops like seedlings and flowers are frequently sold with soil transplantation practices, which directly leads to the soil plough layer becoming shallow or even stripped and eventually disappearing. This type of "non-grain production of cultivated land" with stripped plough layer can cause soil structure damage, nutrient imbalance, and fertility degradation, thus, it is a serious threat to the foundation of national food security and the healthy development of agriculture. The main problem with the stripped "non-grain production of cultivated land" is the lack of a high-quality plough layer. Therefore, a solution promoting the reconstruction of the high-quality plough layer to meet the fundamental needs of crops is key to replanting these soils. However, there is currently no systematic research aimed at solving this problem. 【Method】A novel plough layer reconstruction material was developed using long-lasting organic materials such as herbal peat, moss peat, rice husk biochar, sawdust biochar, active organic material vegetable corn husk, and microbial inoculants. We employed cluster and principal component analyses to identify the minimum data set of quality evaluation indicators for plough layer reconstruction materials, which was then combined with the quality index model to create a comprehensive quality evaluation system. 【Result】The result showed that the plough layer reconstruction materials with moss peat and rice husk biochar as main raw materials had higher quality and could effectively improve the fertility and compact structure of plough layer damaged soils. This material was characterized by a loose texture, bulk density of 0.1347~0.1466g·cm-3, high capillary porosity (64.83%~67.82%), strong water-holding capacity, high organic matter content (658.85~704.92g·kg-1), and high SOC recalcitrance index of 75.27%~84.71%., with a high potential for sequestration and sink enhancement. The minimum data set constructed with SOC, Labile C, HS, TN, TK, capillary porosity, and pH can be used as a quality evaluation system for plough layer reconstruction materials. Based on the above system, the optimal formulation of the plough layer reconstruction material was screened as follows: when moss peat (M) is mixed and configured with rice husk biochar (R) at mass ratios of 1:1, 2:1, 3:1, and then 10:1 with vegetable corn husk (C); ((M+R)10C1, (2M+R)10C1, and (3M+R)10C1), a high-quality ploughing layer reconstruction material can be formed. On "non-grain production of cultivated land," the application of selected plough layer reconstruction materials can dramatically lower soil bulk density and raise soil organic matter content by 177.35% to 204.31% compared to the control. Additionally, the treatment also increased the soil""s effective nutrient content and soil carbon sequestration potential. The plant height, weight, and number of spikes of wheat were higher than those in the control after the application of the plough layer reconstruction material. This resulted in the yield of wheat being 5.6 times higher than that of the control, which demonstrates the benefit of this type of material for crop growth. 【Conclusion】The indicator evaluation system established by this research can comprehensively and objectively evaluate the overall quality of plough layer reconstruction materials, and the materials created with moss peat and rice husk biochar as raw materials showed high application value in improving soil quality, increasing soil carbon sequestration capacity, and restoring crop production.

Abstract:【Objective】The coexistence of cadmium (Cd) and arsenic (As) in soil and water has emerged as a critical global environmental concern due to the significant risks it poses to human health through the food chain. To address this pressing issue, a novel silicon-iron modified biochar (CMSMB) was developed using a co-precipitation-physical mixing method.【Method】The study aimed to comprehensively investigate the remediation capabilities and underlying mechanisms of CMSMB through a series of batch experiments and soil incubation trials in environments contaminated by both Cd and As.【Result】In batch experiments, CMSMB exhibited an impressive maximum adsorption capacity of 272.73 and 17.59 mg?g-1 for Cd(Ⅱ) and As(Ⅲ), respectively. The adsorption processes on the CMSMB surface were intricate, involving a simultaneous interplay of antagonistic and synergistic interactions, and the relative strengths of these interactions were found to be controlled by the concentrations of Cd(Ⅱ) and As(Ⅲ) in the solution. The antagonistic effect primarily originated from the competitive binding of Cd(Ⅱ) and As(Ⅲ) to hydroxyl and aromatic rings. Conversely, the synergistic effect relied on electrostatic adsorption, Cd-As co-precipitation, and the formation of ternary surface complexes. Soil incubation experiments conducted over 20 days revealed significant positive outcomes. The application of CMSMB led to a substantial increase in soil pH and dissolved organic carbon (DOC) content. Consequently, there was a noteworthy decrease (ranging from 64.86% to 74.25%) in the concentration of available Cd in the soil. These changes were attributed to the impact of electrostatic adsorption, precipitation, and complexation resulting from the intricate interplay between CMSMB and alterations in the soil physicochemical properties. However, in the short-term soil incubation, CMSMB exhibited a negligible influence on the bioavailability of As in the soil. The concentration of bioavailable As showed only a slight decline with increasing incubation time which suggests that the remediation effect of CMSMB on As in co-contaminated soils may require a longer duration for observable impacts.【Conclusion】In summary, CMSMB emerges as a potent environmental agent with remarkable efficacy in remediating water contaminated by Cd(Ⅱ) and As(Ⅲ) co-contamination. Furthermore, it demonstrates the ability to passivate Cd in co-contaminated soils, leading to a substantial reduction in the bioavailable Cd. However, its influence on the bioavailability of As in the soil during short-term application appears to be limited. CMSMB demonstrates applicability in the remediation of farmland soils and wastewater contaminated with cadmium and arsenic, found in sources such as mining tailings and agricultural irrigation. However, its long-term remediation capacity, encompassing migration, transformation, and microbiological mechanisms, requires further in-depth exploration and validation.

Abstract:【Objective】The Sichuan-Yunnan ecological barrier area is an important ecological function area in China. To reduce the increasing ecological degradation and soil erosion, it is important to research soil erosion and soil conservation functions. 【Method】The Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to characterize the spatial distribution of soil erosion and soil retention in 2000, 2010, 2015, and 2020. The GeoDetector was applied to detect the main controlling factors of soil erosion. 【Result】The results showed that the soil erosion modulus and the total amount of soil erosion in the four phases showed a trend of decreasing and then increasing. The erosion intensity was dominated by mild erosion, accounting for about 85% of the whole area, and mainly distributed in the eastern part of the area. The light and more than light erosion intensity were mostly distributed in the western part. Soil conservation modulus in 2000, 2010, 2015, and 2020 were 4.0×103, 3.5×103, 3.5×103, and 4.5×103 t?km-2, respectively, and soil conservation amount were 9.6×108, 8.3×108, 8.2×108, and 1.1×109 t, respectively. The influence degree of each influencing factor on soil erosion in descending order was as follows: land use type, elevation, fractional vegetation cover, soil erodibility, erosivity, and slope. The interaction effects between factors on soil erosion were greater than that single factor, and the interaction between land use type and soil erodibility had the strongest effects on soil erosion.【Conclusion】Although soil erosion in the Sichuan-Yunnan ecological barrier area shows a worsening trend, soil conservation is gradually improving, and soil conservation is stronger than soil erosion, and overall, the Sichuan-Yunnan area is developing in a better direction.

Abstract:The environmental emission of nitrogen (N) permeates through the entire food chain and ecological system. Nitrogen-efficient technologies in crop or livestock production alone have proven ineffective in controlling N pollution, necessitating the innovation of systematic research and management methods. A new framework, CAFE, that defines four N management systems (Cropping system, Animal-crop system, Food system, and landscape Ecosystem) hierarchically, has been established to quantify N flow to a broader perspective and help understand the complex dynamics and interactions across different N cycle systems. CAFE can be applied globally for different regions, helping elucidate the differences of N management levels in various regions and providing a new perspective and methodology for global sustainable N management. Applying CAFE to 13 representative countries reveals that the N surplus in most countries increased and the NUE decreased with the increase of the level of managed system. The N surplus in the animal-crop system, food system, and regional ecosystem increased by 152% (median), 230%, and 287%, respectively, based on the cropping system. The N surplus eventually increased from 3-153 kg·hm-2 in the cropping system to 63-464 kg·hm-2 in the regional ecosystem. At the same time, NUE decreased from 55% (median) in the cropping system to 30% in the animal-crop system and 18% in the food system. N loss increases gradually from crop production to primary agricultural products, food production, and consumption. Although the trend of N surplus increase is consistent across all countries, the magnitude of the increase varies considerably among countries, determining the different priorities for improving N management in each country. For China, as the high nitrogen surplus mainly comes from the cropping system, efforts need to be made to reduce the N surplus in cropland by promoting best management practices and adjusting the structure of N inputs. For most Western countries, the system outside the cropland contributes more to the total N surplus, and attention should be given to the N recycling of related systems. For example, the Netherlands needs to focus on matching crop-livestock structure, increasing feed self-sufficiency rate, and reducing livestock density to decrease N surplus in the animal-crop system. Japan needs to further reduce food waste or increase circulation, while African countries need to reduce crop storage waste and improve overall productivity. The analysis of the global CAFE system shows that the main factors affecting the surplus increment across systems include the structure of N input in cropland, livestock density, feed self-sufficiency rate, and the relationship between food trade and domestic supply and demand. However, these factors have not yet received attention in global N management. CAFE provides a consistent quantitative method for global N whole-chain management, which is helpful for cross-regional comparison, experience sharing, and policy formulation.

Abstract:【Objective】The black soil region of Northeast China is an important commodity grain production base in China. However, intense soil erosion has led to a decline in soil health and ecological functions in the region. 【Method】The microbial diversity of soils at different slope positions and their relationship with the co-occurrence network was analyzed using slope farmland soils from typical black soil areas, and the effects of erosion-deposition on soil microbial communities were investigated in combination with soil physicochemical properties. 【Result】The results showed that: (ⅰ) Soil erosion significantly reduced microbial α-diversity while deposition increased it. Soil organic carbon (SOC) and mean weight diameter (MWD) had a significant positive correlation with microbial diversity. (ⅱ) Erosion-deposition did not change the major dominant groups at the phylum or family levels of bacterial and fungal. However, at the phylum and family level, changes in the relative abundance of the main dominant groups at the fungal were more pronounced than in the case of bacteria. (ⅲ) The results of redundancy analyses indicated that erosion-deposition, by altering SOC, total phosphorus (TP), MWD, etc., led to different trends in the relative abundance of species significantly affected by them. (ⅳ) Soil erosion significantly reduced the complexity of the bacterial co-occurrence network, whose node and edge respectively decreased from 540 and 572 (top of slope) to 488 and 520 (lower slope) and increased to 546 and 602 (foot of slope). Also, soil erosion significantly increased the number of clustering coefficients, the number of which increased from 0.38 (top of the slope) to 0.41 (lower slope). Meanwhile, erosion-deposition significantly changed the number of nodes of the fungal network, the number of which decreased from 223 (foot of slope) to 187 (lower slope) and increased to 201 (foot of slope). In addition, the bacterial network stability showed a decreasing trend with increasing erosion intensity while the fungal network stability showed a decreasing and then increasing trend.【Conclusion】This study revealed the changes and driving factors of soil microbial diversity and community structure under erosion-depositions and provided a theoretical basis for further understanding of the interaction between soil physicochemical properties and microbes in slope farmland of typical black soil area.

Abstract:【Objective】As an important indicator of soil quality, black soil layer thickness plays an irreplaceable role in sustainable soil development, food security and ecological functions. However, analyses based on soil profile survey data are often based on small sample sizes and small regional scales, and most of them are based on point data statistics only. However, the studies lacked spatial variability prediction analyses, hence, there is an urgent need for rapid surveys of the thickness of the black soil layer and high-performance spatial prediction methods.【Method】In this paper, a series of sample data of black soil thickness at 357 sample points in Heilongjiang Province were obtained by the rapid acquisition method of "shallow excavation + deep soil drilling" for black soil thickness at multiple burrows in newly constructed sample points. The spatial variability of black soil thickness and its uncertainty were predicted through the optimisation of parameters of the Random Forest Prediction Model (RPFPM). The impacts of the different burrow observations and their mean samples on the optimization of the model"s prediction accuracy and stability were analyzed, and the spatial prediction potentials of the model were evaluated.【Result】The predicted average thickness of the black soil layer in the arable land in the study area was 53.42 cm, and the new method of rapid acquisition and prediction of black soil layer thickness was effective and can be used as an alternative to the profiling method. The spatial variation explanatory power R2 of the optimized random forest model for predicting black soil thickness reached 60%, which could finely depict the spatial differentiation of black soil thickness. Also, the randomness of a single observation burrow at a sample point could change the importance value of the covariates predicted by the model, and even affect the spatial prediction of the distribution pattern of the black soil thickness. Compared with the spatial prediction on the mean value of several observations, the spatial prediction on a single observation had lower accuracy for uncertainty assessment of the spatial distribution and significantly reduced prediction performance. Interestingly, the cross-validation metrics and scatterplot analyses indicated that the optimized Random Forest model had a stable spatial prediction potential of the black soil thickness.【Conclusion】This study provides a new perspective and new ways for high-precision and rapid investigation and prediction of black soil layer thickness.

Abstract:【Objective】Carbon sequestration and emission reduction of farmland soil is an important area to realize the "dual carbon" strategy in agriculture. This study attempted to explore the impact of long-term crop cultivation on soil organic carbon (SOC) under different climatic conditions, soil properties, and agronomic measures, as well as to clarify the natural and artificial conditions conducive to SOC accumulation under long-term crop cultivation in China.【Method】This study collected and sorted out 147 published literature on SOC changes in China during cultivation over 5 years from 1990 to 2022, and finally established 934 databases. Meta-analysis was used to quantitatively analyze the changes in SOC under long-term crop cultivation in China, and systematically analyze the influence degree of various factors.【Result】Under the influence of climate, initial soil properties, and agronomic measures, the SOC content in the topsoil of long-term crop cultivation in China increased by 17.85% overall. However, the increase in organic carbon decreased with the deepening of the soil layer. The warm-temperate zone climate had the most obvious effect on SOC accumulation, reaching 33.62%. When at an altitude of 200~600 m, a temperature of 8~15 ℃, and precipitation of 600~1 000 mm, the accumulation of SOC was the highest, increasing by 28.90%, 35.11%, and 31.33%, respectively. In addition to pH and alkali-N, the increase in SOC under long-term crop cultivation continued to decrease with the increase of initial SOC, total nitrogen, and other available nutrients. When the initial nutrient content in the soil was at a low level (0~10 g·kg-1 SOC, 0~0.9 g·kg-1 TN, 0~10 mg·kg-1 Olsen-P and 0~75 mg·kg-1 Olsen-K), the increase in SOC was the highest, increasing by 35.65%, 44.72%, 24.98%, and 6.38%, respectively. In addition, all conventional agronomic measures currently have an increasing effect on SOC content. The total straw return had the largest increase in SOC, which was 33.62%. Long-term non-fertilization had no significant impact on SOC.【Conclusion】The low altitude warm temperate zone in China was more conducive to the accumulation of SOC in farmland soil. As the soil layer deepens, the increase in SOC caused by long-term crop cultivation gradually decreases. In addition to alkali-N, soils with poorer initial nutrients (SOC, total nitrogen, Olsen-P and Olsen-K), are more conducive to the accumulation of SOC. Among various field management (straw returning, film covering, fertilization and tillage), total straw return is the most effective in promoting the accumulation of SOC. These research results are of great significance for achieving carbon neutrality and sustainable development in agriculture as soon as possible.

Abstract:【Objective】Fungal decomposition plays a key role as the primary driving force of the nutrient cycling and energy flow in the soil. However, the response characteristics of fungal communities to different types of straw carbon inputs and the key environmental factors at the aggregate scale are not yet clear.【Method】In this study, corn straw was used as the experimental, and three treatments were set according to the equal carbon content of straw returning: regular crushed straw (RS), decomposed straw (DS) and straw biochar (BC). A control group without straw application (CK) was also set up. The study aimed to investigate the effects of different carbon types from straws on the diversity, composition, and distribution of fungi in soil macroaggregates (>0.25 mm) and microaggregates (<0.25 mm), as well as the interactions within fungal communities. Furthermore, key environmental factors influencing the variation of soil fungal communities were explored.【Result】The results of a 2-year field experiment indicate that RS treatment significantly reduced fungal α diversity (P < 0.05) in microaggregates (< 0.25 mm) and macroaggregates (> 0.25 mm). The top three dominant phyla in each treatment were Ascomycota, Mortierellomycota, and Basidiomycota, while the top three dominant genera were Plectosphaerella, Chaetomium, and Mortierella. Compared to different aggregate size fractions, the treatment with straw carbon significantly induced differentiation in fungal community structure (P < 0.01), with notably distinct fungal community structure observed in the RS treatment compared to the other treatments. Also, analysis of fungal co-occurrence network showed that BC treatment increased the number of nodes (10.08%) and modularity (5.55%) while DS treatment increased the number of nodes (11.17%), the number of edges (32.57%) and the average degree of nodes (19.27%) included in the co-occurrence network, and all of which improved the structural stability of the fungal network of soil aggregates. The Mantel test analysis found that ammonium nitrogen (AN) and pH were the key environmental factors affecting the fungal community structure of soil aggregates, with the fungal community in the RS treatment being the most influenced by soil environmental factors. The prediction analysis of fungal community function showed that the input of straw carbon could reduce the relative abundance of pathogenic fungi and reduce the occurrence of soil-borne diseases in farmland. 【Conclusion】Our results reveal that in the short term, different soil aggregates of fungi are more susceptible to the influence of straw carbon types, leading to differentiation. The addition of decomposed straw and straw biochar can increase soil AN content, thereby increasing the complexity of the fungal network, thus, promoting fungal community stability. Therefore, for practical applications, it is advisable to consider appropriately increasing the input of decomposed straw or straw biochar to promote the stability of soil ecological functions.

Abstract:The rhizosphere microbiome can strongly promote plant growth and health by increasing nutrient availability, enhancing plant stress tolerance, and improving disease resistance. It has become an important pathway to support the development of green agriculture to fully exploit the plant-beneficial functions of the rhizosphere microbiome. Therefore, there is a great need to systematically investigate the assembly processes and functional and regulation mechanisms of the rhizosphere microbiome, to enhance the ecosystem service functionality and promote the productivity, quality, and nutrient use efficiency of crops. Plants have the capability of recruiting specific functional microbes that are advantageous for their growth under diverse environmental conditions. As such, a fundamental correlation presents between the functional requirements of plants to adapt to environmental stresses and the functional features of the rhizosphere microbiome. We defined this trait, of which the rhizosphere microbiome-derived specific functions compensate the functional requirements of the host plant, as the “functional compensatory assembly” of the rhizosphere microbiome. In this review, we introduced this concept in four stages: (1) the development and current status of rhizosphere microbiome assembly concept, (2) the structural features and impacting factors of rhizosphere microbiome, (3) the functional characteristics of rhizosphere microbiome and their mechanisms in promoting plant growth, and (4) the concept and intension of functional compensatory assembly of rhizosphere microbiome. Firstly, three models of “two-step selection”, “multistep selection”, and “amplification selection” have been proposed to describe the compositional assembly process of the rhizosphere microbiome. These models demonstrate that the rhizosphere microbiome assembly process is a selective enrichment process of the soil microbiome under rhizodeposition. Secondly, it has been established that the composition of the rhizosphere microbiome is primarily influenced by soil properties and plant genotypes. Presently, there is a growing interest in identifying and clarifying the crucial host genes that can regulate the colonization of specific microbial taxa through microbiome genome-wide association studies (mGWAS) between the host plant’s genetic and the rhizosphere microbiome. Thirdly, the interaction between the rhizosphere functional microbes and the host plant under various environmental conditions has been extensively researched. Briefly, plant recruits specific functional microbes in the rhizosphere by releasing specific exudates, while enriched functional microbes can also promote the plants’ resistance to environmental stress through diverse approaches. Finally, the concept of the functional compensation assembly of rhizosphere microbiome was introduced. We elaborated on the content of functional compensation assembly, covering its condition and object, process and mechanism, regulation, and application strategy. To summarize, we highlighted the potential for enhancing resource utilization efficiency and promoting crop growth and health by increasing the functional compensation ability of the rhizosphere microbiome. However, although our fundament research achievement is growing exponentially, there is much to study before fully exploiting the plant beneficial functions of the rhizosphere microbiome. We encourage exploration of the mechanisms of functional compensation and exploit strategies of rhizosphere microbiome, improve the theoretical framework of the functional compensation assembly, and incorporate it into the soil quality assessment and diagnosis system. This review could present a theoretical basis to enhance the efficiency of resource utilization and crop productivity, hence providing new insights for promoting the green transition of agriculture.

Abstract:China’s protected horticulture largely depends on soils as growth medium with low to medium technology, which is characterized by high input, high output, and intensive soil use. The cultivation area of the protected horticulture was 2.67 million hm2 in 2021, accounting for more than 80% of the global protected horticulture area. However, the protected cultivation resulted in soil degradation, non-point pollution, increased greenhouse gas emissions, and loss of crop yield and quality. This study focused on soil sustainability in protected horticulture. It summarized the obstacles that limited the sustainability of protected horticulture, which were the imbalance of soil nutrients, low soil environmental quality, the penalty of crop yield and quality, and backward land management and policy. These obstacles were mainly attributed to the low accuracy of plastic greenhouse environmental control and fertilization caused by low technology of protected facility, soil continuous cropping obstacles induced by inappropriate fertilization and monocropping, and less integrative innovation on soil management technology due to the lack of suitable land policy. This study proposed seven strategies to address current soil unsustainability, including soil profile design when building a plastic greenhouse, soil remediation at the fallow period, plastic greenhouse environmental regulation, control of soil input, buildup of crop rotation mode, plant resistance improvement, and the adaptation of land use policy. These strategies are expected to provide reasonable and scientific foundations for sustainable soil management in plastic greenhouses of low-to-medium technology possessed by smallholders.

Abstract:【Objective】Mineral-associated organic carbon (MAOC) is the most important of soil organic carbon (SOC), and its mineralization characteristics have an important impact on soil carbon sequestration and global climate change. As an important topographic factor, slope position significantly affects the interaction and stability of organic carbon and soil minerals. However, the influence of slope positions on mineralization characteristics of MAOC in soils is not fully understood. 【Method】In this study, typical citrus orchard soils at different slope positions were sampled, and the aggregates with sizes of >2, 2~0.25, 0.25~0.053, and <0.053 mm were obtained by physical fractionation. Moreover, the MAOC in aggregates were separated to investigate the mineralization characteristics of MAOC at varying slope positions (upper slope, middle slope, and lower slope) through indoor cultivation. The influence of soil physicochemical factors and hydrophobicity on MAOC mineralization was analyzed by Infrared spectroscopy (FTIR), Redundancy analysis (RDA), and Hierarchical partitioning analysis. 【Result】The results showed that the cumulative mineralization (Ct), mineralization rate and potential mineralization (Co) of MAOC in citrus orchard soil at lower slopes were significantly higher than those at upper and middle slopes, but the ratio of Co/MAOC at lower slope was significantly lower compared with upper and middle slopes. With the decrease in aggregate size, the Ct, mineralization rate, and Co of MAOC in citrus orchard soil at each slope position showed an upward trend, while the mineralization intensity of MAOC gradually weakened. RDA results showed that the Co was significantly positively correlated with pH, SOC, MAOC, TN, and C/N (P<0.05), and significantly negatively correlated with iron and aluminum oxides (Fed/Ald, Feo/Alo, and Fep/Alp) and hydrophobicity (P<0.05). Co/MAOC was significantly positively correlated with iron and aluminum oxides and hydrophobicity, but significantly negatively correlated with Co, Ct, pH, SOC, MAOC, TN, and C/N. Hierarchical partitioning analysis revealed that Alo, Alp, and Fep emerged as significant factors influencing the mineralization of MAOC. Variation decomposition analysis showed that the combined effects of Alo, Alp, Fep, C/N, MAOC, and Feo significantly affected MAOC mineralization in aggregates with different particle sizes at different slope positions. 【Conclusion】The slope positions have obvious effects on the mineralization characteristics of MAOC in aggregates in citrus orchard soils. The findings of this study are of great significance for understanding the formation mechanisms and stability of mineral-bound organic carbon in soil aggregates and in enhancing soil organic carbon sequestration in citrus orchards at different slope positions in hilly regions of southern China.

Abstract:Phyllosilicate minerals and aluminum (Al) oxides are the main sources of Al activation in the soil acidification process and they are also active parts of soil chemical reactions. 【Objective】The phyllosilicate minerals in soils are usually tightly bound to Al oxides and organic matter. Therefore, Al mobilization during soil acidification should be affected by soil organic matter and Al oxides. However, the effect and mechanism of Al oxides on the activation of Al during phyllosilicate minerals and soil acidification are not well understood. 【Method】Since the mobilization of Al is very sensitive to changes in system pH, the pH of mineral and soil suspensions was precisely controlled by constant pH automatic potentiometric titrator in this study, and the effects of gibbsite on kaolinite and amorphous Al(OH)3 on Al mobilization during kaolinite and montmorillonite acidification were studied. In addition, the Al activation kinetics of two Al oxides and two phyllosilicate minerals at different pH were studied. Finally, a red soil developed from quaternary red clay was treated with Al coating, and the effect of Al coating on soil Al activation was studied. 【Result】Al coating treatment did not change the d values of the diffraction peaks for kaolinite and montmorillonite. However, the intensity of the diffraction peaks for the two minerals decreased. This can be attributed to the physical masking of Al oxides on the kaolinite and montmorillonite. The results showed that the gibbsite can promote the mobilization of Al during kaolinite acidification. The Al coating can inhibit the production of exchangeable Al and promote the activation of soluble Al during kaolinite acidification. For montmorillonite, amorphous Al(OH)3 was found to promote the production of exchangeable Al. The Elovich equation and the zero-order kinetic equation were used to fit the kinetic data, respectively. The results of Al mobilization kinetics of the four minerals showed that the release rate of Al followed the order: amorphous Al(OH)3 > montmorillonite > kaolinite > gibbsite. The releasing order of Al from montmorillonite, kaolinite and gibbsite was consistent with their weathering sequence. After red soil was treated with Al coating, the contents of exchangeable Al and soluble Al in the soil increased significantly when the soil was acidified to pH 4.3, and the increase of soluble Al was greater than that of exchangeable Al. This is consistent with the result of Al-coated kaolinite, mainly because the main clay mineral in the soil was kaolinite. The increase in exchangeable Al was mainly because some hydromica and vermiculite were also present in the soil.【Conclusion】 Therefore, Al oxides showed different effects on the mobilization of Al from different phyllosilicate minerals, which was mainly related to the nature of the minerals (e.g., 1:1 or 2:1 phyllosilicate minerals). The influence of Al oxides on Al mobilization in soils during soil acidification was mainly related to the type and content of clay minerals contained in the soils. The results of this study can provide evidence for elucidating the activation mechanism of soil Al and a reference for the inhibition of soil Al mobilization during soil acidification.