Soil cadmium (Cd) contamination poses a persistent challenge to the sustainable management of agricultural land, as conventional remediation technologies are often costly, disruptive, and difficult to implement at scale. Although phytoremediation is environmentally friendly, its large-scale application has been constrained by the poor adaptability and low economic viability of hyperaccumulator-based models. To address this limitation, this study develops and evaluates a tobacco-rapeseed rotation (TRR) model that integrates high-biomass economic crops into a continuous, cross-seasonal remediation framework. Based on one-year field experiments combined with economic assessment and life cycle analysis, the performance of the TRR was systematically compared with representative phytoremediation pathways. The TRR achieved an average annual Cd removal of 349.91 g/ha, while exhibiting the lowest unit Cd removal cost (105.31 CNY/g) and the shortest investment payback period (26 years) among the evaluated models. Life cycle assessment revealed that the environmental burden of the TRR was primarily associated with post-harvest biomass disposal, indicating substantial potential for impact reduction through biomass valorization. Scenario analysis further demonstrated that, under low-level Cd contamination, the TRR can simultaneously ensure food safety and generate stable economic returns with manageable health risks. Overall, the TRR represents a scalable and economically self-sustaining "remediate-by-farming" strategy, offering a practical pathway for the sustainable management and safe utilization of cadmium-contaminated farmland.

Soil pollution poses a profound threat to ecosystem and human health. This review proposes a novel framework centered on engineering biological interaction networks for efficient and sustainable soil decontamination, moving beyond the traditional single-species paradigm. We dissect the architecture and dynamics of key interactions, including plant-plant, plant-microbe, and microbe-microbe interactions, within remediation contexts, elucidating how mechanisms like mutualism, competition, and cross-kingdom signaling govern the fate of heavy metals, organic pollutants, and complex mixtures. Crucially, we explore how these natural networks can be actively engineered through strategies such as targeted bioaugmentation, precision biostimulation, and rational plant community assembly to enhance remediation outcomes. Furthermore, we highlight how cutting-edge multi-omics, synthetic ecology, and computational modeling are transitioning the field from descriptive ecology to predictive network design, enabling the decoding of the soil black box and the rational construction of tailored, resilient remediation consortia. Finally, we discuss the ecological challenges of introducing designed networks and outline a future road map toward precision restoration ecology, where theory-guided interaction network management enables effective, stable, and ecologically sound soil clean-up. This network-centric paradigm represents a fundamental shift from experience-based trial-and-error to a principled design approach for restoring soil health.

Exogenous amendments are crucial for enhancing the remediation efficiency of arsenic-contaminated soils by Pteris vittata. However, their effectiveness is unstable due to various factors, and neglecting their economic costs hinder broader application. In this study, we analyzed 2299 data points from 121 published datasets and used machine learning to predict and optimize the performance of amendments to enhance the phytoextraction efficiency. Using a random forest model, we predicted changes in As accumulation in P. vittata in response to specific amendments, considering 18 parameters across four categories: changes in P. vittata, amendments, soil properties, and cultivation conditions. The model achieved an R2 value of 0.846. Using %IncMSE to quantify parameter contribution, we found that the biomass of P. vittata had a greater influence than the As concentration. Additionally, amendment type, application time, cultivation duration, and soil-available As were key factors in enhancing As accumulation in P. vittata. Regarding economic cost, different amendments required an investment ranging from 0.57 to 3903.86 CNY to enhance 1 g of As accumulation in P. vittata. Among these, phosphate fertilizers had the lowest cost, whereas calcium acetate, ethylenediamine-N,N'-disuccinic acid, and glutathione did not have economic advantages as amendments. This study offers guidance on the development of amendments, providing an important reference for the practical application of phytoextraction in As-contaminated soils.

A sustainable strategy for cadmium (Cd)-contaminated farmland was developed using a rape-rice-rice rotation system. This method combines early maturing and high Cd-accumulating rape variety with low Cd-accumulating rice varieties and alkaline Si-rich fertilizer. Field experiments compared different planting patterns: single-season rice (SR), oilseed rape-rice rotation (OR), rice-rice rotation (RR), modified oilseed rape-rice rotation (MOR), and integrated threecrop rotation (MORR). MORR significantly reduced Cd content in rice grains, boost total crop yield, and enhanced soil Cd removal. It achieved a comprehensive evaluation index of 0.99, safe crop production over three seasons, a soil Cd removal rate of 87.338 g/ha/yr, and economic benefits of 34,915 CNY & sdot;ha- 1. Simulations based on the Cd input-output balance showed MORR cleaned soil Cd below standards in 12 years, outperforming the 15 years required by the Sedum alfredii and peanut rotation (SP). MORR minimized health risks from Cd exposure, balancing safe production, soil remediation, and farmer income, offering a viable solution for sustainable use of Cd-contaminated farmland.

Elucidating the dominant factors governing heavy metal accumulation and their spatial heterogeneity in soils is fundamental to implementing science-based environmental management protocols. In this study, a Geodetector model, spatial interpolation, bivariate local Moran’s I (BLMI), and hotspot analysis were adopted to reveal the spatial pattern and driving mechanisms of soil cadmium (Cd) across six townships in southern Shimen County, Hunan Province. Results showed that Cd accumulation in the study area was predominantly controlled by natural factors, though anthropogenic contributions were also significant. Strata (q = 0.068), soil type (q = 0.045), and atmospheric deposition (q = 0.046) emerged as the most influential factors. The interaction between different driving factors exhibited a synergistic enhancing effect. Spatial interpolation revealed elevated Cd concentrations primarily clustered in central and western regions, particularly concentrated in Jiashan Town. BLMI analysis confirmed significant spatial correlations between Cd distribution and driving factors, and hotspot areas showing strong spatial coherence with strata and soil type. This study provides valuable insights for understanding the driving mechanisms of soil heavy metal pollution and informs targeted contamination control strategies.

Given that atmospheric Pb has become the primary source of Pb in wheat grains, scientifically managing atmospheric Pb pollution is a notable global challenge. Identifying the critical periods for Pb absorption in straw and accumulation in grains was essential for developing targeted mitigation strategies, as the varying nutrient demands of wheat across different growth stages might have influenced Pb accumulation. To investigate this, a pot experiment using Pb exposure and isotope tracing was conducted. The results showed that wheat directly absorbed Pb through its aerial parts, with Pb content in both the straw and grains increasing with exposure duration. A clear coupling relationship was observed between Pb absorption in straw and its accumulation in grains. Grain filling stage (FS) is a critical period for Pb accumulation and pollution control in wheat straw and grains, contributing approximately 41.14-41.87 % to Pb absorption in straw and 56.21-58.16 % to Pb accumulation in grains. Furthermore, Pb accumulation during the greening, jointing, and booting stages contributed 40.62-42.61 % to the total Pb in grains, which reflects the redistribution of Pb stored in the shoots before FS to the grains. Further isotope tracing also revealed that FS contributed 51.06 % of Pb accumulation in the grains, whereas the redistribution of Pb absorbed by the straw before FS contributed approximately 44.33 % to grain Pb content. This study highlights the FS as a critical period for Pb accumulation in both wheat straw and grains, despite it accounting for only 13.89 % of the total growth period. This highlights the importance of enhancing atmospheric Pb contamination control at this this stage to ensure the quality and safety of wheat production.

Biotic turnover and innovation during the terminal Ediacaran to Early Cambrian have been widely linked to tectonic, sedimentary, climatic, and oceanic environmental changes due to their temporal coincidence. However, the precise interconnections between these environmental factors and biological co-evolution remain uncertain. The Yangtze Block preserves essential records to investigate this issue. In this study, we use lithostratigraphic logs and correlations of the terminal Ediacaran to Early Cambrian successions across the upper Yangtze Block to suggest that, the significant lithological change from dolomite to siliciclastic-dominated sedimentation indicates the tectono-sedimentary environment transition from a shallow-water carbonate platform to a deep-water siliciclastic basin. Extensional tectonic activities, enhanced continental weathering, and rising sea levels led to rapid subsidence and extensive siliciclastic sediment accumulation during the Early Cambrian, facilitating this transformation. This sedimentary environment transition also correlates with marine transgression on a global scale. Further, qualitative comparisons of detrital zircon age spectra from this period place the Yangtze Block near northern India, confirming its paleogeographic and material connections with Gondwana. By integrating these findings and geological data on tectonism, sedimentation, marine environment, and biological evolution, this paper constructs a synthetic framework to propose that enhanced continental weathering and marine transgression during the assembly of Gondwana initially triggered changes in lithofacies and seawater conditions, potentially driving early bio-evolution. Our research highlights the interactions among multiple environmental factors during this critical geological period, which contributes to understanding the trigger of the Cambrian explosion.

Accurate prediction of heavy metals (HMs) spatial distribution in mining areas is crucial for pollution management. However, predicting the spatial distribution of HMs remains a significant challenge in mining areas with complex terrain and variable contaminant transport pathways. This study aims to optimize the spatial prediction of arsenic (As) distribution in the Shimen realgar mining area, the largest in Asia, by integrating machine learning models with kriging interpolation and feature selection techniques. The results show that the Random Forest (RF) model achieved the best performance in predicting soil As concentration, with an R2 of 0.84 for the test data. Incorporating environmental variables improved the spatial prediction accuracy, with RF (R2 = 0.76, RMSE = 24.68 mg/kg) and Random Forest Regression Kriging (RFRK) (R2 = 0.78, RMSE = 23.46 mg/kg) outperforming ordinary kriging and geographically weighted regression kriging. Importance analysis and recursive feature elimination further optimized the model, leading to a 5 % increase in R2 and a reduction of RMSE by 8 %-12.4 %. The optimized RFRK model accurately captured the spatial distribution of As in the mining area, revealing the outward diffusion pattern of As from the smelting plant. The findings highlight the critical role of feature selection in improving prediction accuracy in highly polluted and complex terrain regions, an aspect that has often been overlooked in previous studies. This study provides a practical framework for spatial prediction of contaminants in similar areas, enhancing the understanding of pollution distribution.

Dissolved organic matter (DOM) is a crucial amendment that enhances soil arsenic (As) mobilization and promoting contaminated soil remediation; however, the key mechanisms and dominant material properties remain unclear. This study integrates soil cultivation experiments and density functional theory (DFT) simulations to analyze the mobilization efficiency and molecular mechanisms of DOM's functional group types, structures, and combinations on soil As. Carboxyl groups exhibited a high affinity for goethite (adsorption energy of -6.53 eV), demonstrating stronger competitiveness than hydroxyl, amino, and sulfhydryl groups in enhancing soil As mobilization. The optimized carboxyl structural features-including adjacent functional groups, high carboxyl density, and strong acidity-were exemplified by oxalic acid, which achieved 82.5% higher water-soluble As than the control. Hydroxyl substitution of alpha-H, without changing carboxyl groups, increased bonding strength and weak forces with goethite, resulting in lower adsorption energy and higher As mobilization efficiency. Surface electrostatic potential, adsorption energy and pH were the main properties affecting soil As mobilization by DOM, indicating that this process is closely related to an electrostatically promoted coordination adsorption competitive mechanism and is co-regulated by protonation mediated by pH. Using oxalic acid combined with potassium humate as mobilizer, the aboveground As accumulation in Pteris vittata was enhanced by 73.8%. From a novel perspective of functional group types, structures, and combinations, we revealed the mobilization process and key controlling factors of DOM on soil As. Our study provides a methodological reference for the development of soil heavy metal(loid) mobilization materials and a scientific basis for further remediation based on mobilization technologies.

Flooding, carrying sediments, inundates farmlands across the world due to extreme adverse weather conditions. The casualties and property damage associated with flooding are important direct impacts. However, there is currently insufficient understanding of the remobilization and distribution of heavy metals (HMs) caused by flooding. Few studies have specifically considered flooding as a pathway for HMs contamination of soil. Herein, a novel methodological framework for revealing the input pathways of HMs in agricultural soils in mining-intensive areas is proposed and applied. Flooding is considered one of the pathways for HMs inputs during source apportionment. The results demonstrated a high degree of overlap between the distribution characteristics of major HMs in agricultural soils and sediments. The degree of soil Cd pollution was significantly positively correlated with the inundation depth in the flooded area. It took 8.4-11.5 times of flood inundation or 98.5-119.9 years of accumulation of atmospheric deposition to reach HMs contamination levels in the soil of the study area. Flooding brought in most of the soil Cd, while atmospheric deposition was the primary input pathway for soil Pb and Zn. Our results identified the role of flood inundation on the input of HMs in mining-intensive areas. These results demonstrated the value of our framework for studying the impact of flooding on HMs in agricultural soils from the perspective of input pathways, providing new insights not only into identifying the sources of soil HMs but also into enhancing understanding of the impact of flooding on soil environments. With the potential increase in the frequency and intensity of flooding inundating farmlands in the future, it is essential to consider flooding as a pathway for HMs inputs in order to comprehensively assess their environmental impact.

The existing efficiency indicators for phytoremediation cannot fully characterise the economic costs and application potential of remediation plants. In this study, we proposed a new strategy for selecting remediation plants based on economic indicators (cost per unit of heavy metal removal). Based on field experiments and data collection, we conducted cost-benefit analyses under various scenarios to compare the application prospects of four cadmium (Cd)-accumulators (Hylotelephium spectabile, Sedum alfredii, Sedum plumbizincicola and tobacco) on slightly Cd-contaminated farmland soil. Utilizing the current screening strategy, which prioritized remediation indicators only, we found that in Cd-contaminated soil, S. plumbizincicola exhibited the best ability to uptake Cd (250 g ha(-1)). However, applying the new strategy that combined economic and remediation indicators, the Monte Carlo simulations results showed that tobacco showed the lowest cost per gram of Cd uptake (546 RMB g(-1)). Combining scenario simulation and cost-benefit analysis, tobacco achieved the earliest positive net present value benefit, indicating a higher application potential in slightly Cd-contaminated soil. Additionally, the spatial distribution and optimal temperature range for tobacco cultivation were found to be superior to those of the other three accumulators, which was consistent with the assessment results of the new screening strategy. The indicator proposed in this study, namely, the cost per unit of heavy metal removal, considers both the remediation efficiency and economic cost. This holds significant value for selecting remediation plants with application potential and provides a crucial basis for decision-making in the development of future phytoremediation strategies and the implementation of large-scale applications.

In response to the safety risks posed by cadmium (Cd)-contaminated rice fields worldwide, a suitable production-and-restoration strategy is required for actual agricultural practices. To investigate the remediation effects of different accumulation varieties in rapeseed-rice cropping systems and their influence on Cd migration and transportation, field experiments were conducted based on different planting combinations (FWHR, conventional rice variety (HR) monoculture under fallow; FWLR, low Cd-accumulating rice variety (LR) monoculture under fallow; LOLR, LO (low Cd-accumulating rapeseed variety)-LR rotation; LOHR, LO-HR rotation; HOLR, HO (high Cd-accumulating rapeseed variety)-LR rotation; HOHR, HO-HR rotation). The study found that a rapeseed and rice rotation with appropriate varieties could reduce the rice grain Cd content, increase rice yield, and remove soil Cd without affecting agricultural production efficiency. Compared to the fallow-conventional rice pattern, various rapeseed-rice rotations reduced the Cd content of rice grains by 15 %-38 %, and significantly increased the available potassium (Ava-K) in the subsequent rice soil by 29.6-56.4 mg/kg. The total economic benefits increased by $500-$1800 per hectare. A high accumulation variety of rapeseed and low accumulation variety of rice produced the most effective reduction in Cd levels, with a reduction rate of 38 % in brown rice and an annual removal rate of 24.42 g/hm2. This combination also resulted in a 29 % increase in rice yield compared to the fallow-low accumulation variety rice pattern. Structural equation modeling revealed that with the combined action of crop rotation and variety selection the crop rotation directly reduced the soil available Cd or had an indirect effect by weakening the root-zone acidification effect and increasing soil Ava-P. The rotation of rapeseed and rice with carefully selected matching varieties is a feasible solution for the safe production and pollution remediation of Cd-contaminated paddy fields.

Low -dosage nitrate pollutants can contribute to eutrophication in surface water bodies, such as lakes and reservoirs. This study employed assembled denitrifying bacterial -fungal communities as bio-denitrifiers, in combination with zero-valent iron (ZVI), to treat micro -polluted water. Immobilized bacterial -fungal mixed communities (IBFMC) reactors demonstrated their ability to reduce nitrate and organic carbon by over 43.2 % and 53.7 %, respectively. Compared to IBFMC reactors, IBFMC combined with ZVI (IBFMC@ZVI) reactors exhibited enhanced removal efficiencies for nitrate and organic carbon, reaching the highest of 31.55 % and 17.66 %, respectively. The presence of ZVI in the IBFMC@ZVI reactors stimulated various aspects of microbial activity, including the metabolic processes, electron transfer system activities, abundance of functional genes and enzymes, and diversity and richness of microbial communities. The contents of adenosine triphosphate and electron transfer system activities enhanced more than 5.6 and 1.43 folds in the IBFMC@ZVI reactors compared with IBFMC reactors. Furthermore, significant improvement of crucial genes and enzyme denitrification chains was observed in the IBFMC@ZVI reactors. Iron played a central role in enhancing microbial diversity and activity, and promoting the supply, and transfer of inorganic electron donors. This study presents an innovative approach for applying denitrifying bacterial -fungal communities combined with iron enhancing efficient denitrification in micro -polluted water.

Arsenic (As) can accumulate in edible plant parts and thus pose a serious threat to human health. Identifying the contributions of various factors to soil available As is crucial for evaluating environmental risks. However, research quantitatively assessing the importance of soil properties on available As is scarce. In this study, we utilized 442 datasets covering total As, available As, and properties of farmland soils. The five machine learning models were employed to predict soil available As content, and the model with the best predictive performance was selected to calculate the importance of soil properties on available As and interpret the model results. The Random Forest model exhibited the best predictive performance, with R2 for the test set of dryland and paddy fields being 0.83 and 0.82 respectively, while also outperforming other machine learning models in terms of accuracy. Concurrently, evaluating the contribution of soil properties to soil available As revealed that increases in soil total arsenic, pH, organic matter (OM), and cation exchange capacity (CEC) led to higher soil available As content. Among these factors, soil total As had the greatest impact, followed by CEC. The influence of pH on soil available As was greater in dryland compared to OM, while in paddy fields, it was smaller than OM (p<0.01). Sensitivity analysis results indicated that reducing soil total As content had the greatest effect on available As. In both dryland and paddy field soils, reducing soil total As had the most pronounced effect on available As, leading to reductions of 10.09% and 8.48%, respectively. Therefore, prioritizing the regulation of soil total As and CEC is crucial in As contamination management practices to alter As availability in farmland soils.

Rifting of the upper Yangtze carbonate platform in the middle Permian gave rise to Kaijiang-Liangping (KL) and Deyang-Wusheng (DW) rifts in the NE Sichuan basin, SW China. These rifts are well-endowed in gas, hosting eight out of nine discovered gas fields in the Sichuan basin. However, the initiation time and geodynamics driving the rifting are poorly understood, which restricts petroleum evaluation and exploration in the KL and DW regions. Our field surveys found that the basalt and underlying volcano-carbonate olistostrome in Huayingshan Mountain (Mt.) in the NE Sichuan basin are the interlayers within the limestone of the middle Permian Maokou Formation (Fm.). Stratigraphically, the Maokou Fm. and the late Permian sedimentary rocks above it form a mega-sequence from rifting to subsidence. Within the Maokou Fm., the rifting sequence comprises the basalt, volcano-carbonate olistostrome (tephra-rich polymictic breccia limestone) and limestone oligomictic breccia of the slope facies. A new data set composed of stratigraphic, petrologic, geochemical, isotopic and zircon U-Pb analyses shows that the basalt is sub-alkaline basalt and displays OIB-like geochemical signatures. The tephra block is basaltic tuff with abundant lath-shaped plagioclase crystals. Parent magma of the basalt originated from low-degree partial melting of the slightly enriched asthenospheric mantle at the garnet-spinel peridotite transition zone. The basalt and volcano-carbonate olistostrome reveal syn-rifting magmatism in ca. 267 +/- 3 Ma. The KL and DW rift basins developed on the substratum of the upper Yangtze carbonate platform, and were triggered by asthenosphere upwelling during the Wordian stage.

Cadmium (Cd) is a heavy metal that significantly impacts human health and the environment. Microorganisms play a crucial role in reducing heavy metal stress in plants; however, the mechanisms by which microorganisms enhance plant tolerance to Cd stress and the interplay between plants and microorganisms under such stress remain unclear. In this study, Oceanobacillus picturae (O. picturae) was isolated for interaction with soybean seedlings under Cd stress. Results indicated that Cd treatment alone markedly inhibited soybean seedling growth. Conversely, inoculation with O. picturae significantly improved growth indices such as plant height, root length, and fresh weight, while also promoting recovery in soil physiological indicators and pH. Metabolomic and transcriptomic analyses identified 157 genes related to aspartic acid, cysteine, and flavonoid biosynthesis pathways. Sixty-three microbial species were significantly associated with metabolites in these pathways, including pathogenic, adversity-resistant, and bioconductive bacteria. This research experimentally demonstrates, for the first time, the growth-promoting effect of the O. picturae strain on soybean seedlings under non-stress conditions. It also highlights its role in enhancing root growth and reducing Cd accumulation in the roots under Cd stress. Additionally, through the utilization of untargeted metabolomics, metagenomics, and transcriptomics for a multi-omics analysis, we investigated the impact of O. picturae on the soil microbiome and its correlation with differential gene expression in plants. This innovative approach unveils the molecular mechanisms underlying O. picturae's promotion of root growth and adaptation to Cd stress.

【Objective】 Environmental contamination by heavy metals is ubiquitous in many ecosystems. In this paper, we assess heavy metal pollution in sediments of the irrigation canals in the Xiangjiang River basin, as well as their ecological risks. 【Method】 Taking Lei Shui region, an important tributary of the Xiangjiang River, as an example, we analyzed the total contents of As, Cd, Cr, Cu, Ni, Pb and Zn, as well as their water-soluble forms in sediments of the irrigation canals. The geo-accumulation index method and ecological risk coefficient/index method were used to evaluate sediment contamination and its ecological risk. Correlation analysis and principal component analysis were used to elucidate the origin of the heavy metals found in the sediments. 【Result】 The sediments in the irrigation canals in the studied region were severely polluted, with a particularly notable concentration of Cd contamination. The total content of heavy metals in the sediments was 6.4 times the background value, predominantly caused by anthropogenic activities. Ecological risk in the area is hence high, especially the risk of Cd followed by As. The accumulation of As-Cd-Zn and Pb-Cu in the sediments was due to industrial and mining activities, respectively, while Ni, Cr and accumulation of As-Cd-Zn and Pb-Cu was caused by both industrial and mining activities. Ni and Cr in the sediments were naturally originated. 【Conclusion】 The sediments in the irrigation canals in the studied region were severely polluted, with Cd content pronouncedly high exceeding the geological background level by 6.4-fold. Such contamination was predominantly caused by anthropogenic activities. In terms of the ecological risk, Cd was most significant followed by As. The accumulation of As-Cd-Zn and Pb-Cu in the sediments emanated from industrial and mining activities. In contrast, Ni and Cr are naturally originated.

Considering the soil cadmium pollution problem, the Chinese government proposed to estimate the costs and practicality "to completely improve the soil quality by the middle of this century". This study analyzed the challenges in achieving this goal using biophysical data from 10 typical demonstration soil phytoextraction projects. The current annual phytoextraction efficiency was determined as 14.8-490 g ha-1 a-1 at 319 RMB g-1 cadmium. A total of 798 billion RMB and 5 years were required for remediation of cadmium contamination, which was 22 times the investment in soil remediation during 2016-2022. The break-even point of phytoextraction projects was 29 years. The heavy financial burden was considered the primary challenge in improving the environmental quality of such soil. The cost could be reduced by 5.5-35.3 % through optimization measures such as resourcefulness of hyperaccumulator harvests, large-scale breeding, and mechanized management. The break-even point could be shortened to 6-15 years by intercropping/rotating crops, contributing to the goal. Active exploration of phytoextraction efficiency-more efficient accumulators, optimized agronomic measures-is worth practicing.

In this paper, researches on the sourcs of cadmum in soil of Hubei province were concucted. Results of soil profile analysis showed that the accumulation of Cd to a certain extent in the surface soil was mainly caused by the alluvial diluvium of the fourth system and human factors. Correlation analysis revealed the correlation between Cd and other heavy metal. Results of factor and cluster analysis both presented anthropogenic sources, including traffic, industrial and agricultural activities.