Soil & Environmental Health最新文献

Gut microbes are crucial for human health, which are usually accumulated in urban wastewater systems. Seven wastewater treatment plants in Australia with distinct population obesity rates between 18% and 33% were selected for wastewater sampling and analysis. Human gut microbiome were detected using metagenomic sequencing to investigate their associations with the community obesity rate. To unravel this complex relationship, a range of algorithm models, including linear discriminant analysis effect size (LEfSe), similarity percentage analysis (SIMPER), statistical analysis of metagenomic profiles (STAMP), linear models for microarray and RNA-Seq data analysis (LIMMA), Relief, ratio approach for identifying differential abundance (RAIDA), least absolute shrinkage and selection operator (LASSO), support vector machine (SVM), Boruta, DESeq2 and analysis of compositions of microbiomes with bias correction (ANCOM-BC), were used to identify potential bacterial biomarkers for obesity in the wastewater microbiome. Among these algorithm models, LEfSe, LIMMA, SIMPER and SVM are effective in identifying multiple microbial biomarkers. Specific human gut microbes, including Ruminococcus_E, Agathobacter, Fusicatenibacter, Anaerobutyricum, Blautia_A and Neisseria, were identified as potential consensus microbial biomarkers for obesity in the population. A high obesity rate is mainly characterized by a high abundance of pathogenic bacteria and microorganisms associated with xenobiotic biodegradation and metabolism, endocrine and metabolic diseases, and transcription pathways. This study underscores the innovative potential of leveraging human gut microbes in wastewater as biomarkers for monitoring obesity levels across communities, offering a novel, cost-effective, and indirect approach to public health surveillance.

Phytoremediation of contaminated soil is an environmentally-friendly approach to minimize the impacts of nutrients and heavy metals on an ecosystem. Hence, selecting appropriate plants with phytoextraction potential is paramount to remediatie contaminated soils. This study aimed to investigate the nutrient and metal contents of four natural aquatic plants, including Cyperus rotundus, Eleocharis dulcis, Typha angustifolia, and Schoenoplectus grossus. They were grown in the meadow of a small reservoir in Sri Lanka to assess their phytoextraction ability using plant and soil samples collected at 32 sampling points in the meadow. Their biological concentration (roots/soil), accumulation (shoots/soil), and translocation (shoots/roots) factors were determined to assess element mobility and phytoextraction ability. Total K, Na, Mg, Ca, Zn, Cu, Fe, Mn, As, Pb, and Cd contents of plants and soil samples were measured using an Inductivity Couple Plasma Optical Emission Spectrophotometer. ANCOVA was used as a statistical test to assess the best plant type in terms of nutrient and metal absorption. Plant shoots exhibited significantly greater values for P, Na, Mg, Zn, Cd, and Fe than their roots. Their biological concentration, accumulation and translocation factors were not different among the four plant species. However, these values were >1 for all the species, indicating their potential to be used as hyperaccumulators. T. angustifolia, with its high potential for nutrient and metal accumulation and the highest aesthetic appeal, was selected as the best overall wetland species for phytoremediation purposes.

Soil life revolves around microorganisms that are crucial for soil ecosystems and health. In megacities, the combined exposure of multiple pollutants exerts a significant impact on the structures and functions of soil microorganisms; however, there is a lack of empirical studies on this topic. Hence, we conducted a study including urban parks in Beijing, China. The results indicate that bacteria were abundant in the soils of Beijing parks, showing the same dominant groups but different rare groups. The dominant groups included Actinobacteria and Proteobacteria. Candidate phyla radiation bacteria, a large evolutionary radiation of bacterial lineages whose members remain mostly uncultivated, were the main specialists. Under the combined exposure of multiple pollutants, the structures of soil microbial communities in different parks were similar. Community change due to pollutants (31%) was greater than that due to natural factors (2.4%). Among multipollutants, organophosphate esters, led by dibutyl phosphate, had the highest influence on microbial abundance and distribution. An increase in dibutyl phosphate concentration decreased the abundance of Firmicutes, while the abundance of Synergistota was increased. The interactions among pollutants affecting the bacteria were different. Bis(2-chloroethyl) phosphate, nickel and benzo[g,h,i]perylene influenced microorganisms by working with organophosphate esters. High-molecular-weight polycyclic aromatic hydrocarbons, such as benzo[a]pyrene and benzo[g,h,i]perylene, mainly acted on the functional genes and thus affected multiple biogeochemical cycles. Benzo[a]anthracene, bis(2-chloroethyl) phosphate, and arsenic were the primary pollutants affecting metabolic pathways. Our research helps to better understand the impacts of urban environmental pollution on soil microorganisms.

Even though the concentrations of the total cadmium (Cd) in paddy soils from different countries have been reported, the exchangeable-Cd (Ex-Cd) concentrations in these soils are unknown despite its importance in agriculture. This study was conducted with a total of 5460 soil samples collected in Sri Lanka, representing six agro-climatic zones, six soil orders, and three irrigation types. The Ex-Cd concentrations in soil samples were extracted using 0.01 ​M CaCl₂ and analyzed using an inductively coupled plasma-mass spectrophotometry. The Ex-Cd concentrations were <0.31–163 ​μg ​kg⁻¹, with mean and median concentrations being 14.1 and 8.98 ​μg ​kg⁻¹, respectively, which was affected by both agro-climatic and soil conditions. Samples from the Wet zone, particularly the Wet zone Low country, had higher Ex-Cd (24.1 ​μg ​kg⁻¹) than those from the Dry zone Low country (11.6 ​μg ​kg⁻¹). Among the soil orders, Histosols (21.3 ​μg ​kg⁻¹) and Inceptisols (19.5 ​μg ​kg⁻¹) had the highest Cd concentration while Vertisols had the lowest (6.3 ​ ​kg⁻¹). The irrigation types only affected Ex-Cd concentrations in Dry zone Low country, but not in other agro-climatic zones. Overall, it is important to consider agro-climatic zones, soil orders, and irrigation types when implementing agronomic strategies to mitigate the risk associated with Cd accumulation in paddy fields.

Soil fauna including earthworms play a crucial role in various ecosystem functions, thereby contributing to human well-being. The relationships between earthworm populations and environmental factors have frequently been established at regional scales, particularly in urban soils. However, the diversity and community assemblage of earthworms, as well as their influencing mechanism at plot scale, have rarely been studied. Based on the earthworm assemblage from 29 sites in 12 residential communities, the average earthworm abundance, biomass, and species richness were 59.0 individuals/m², 21.7 ​g/m², and 1.59 species, respectively. Based on a generalized linear mixed model, vegetation distribution pattern, vegetative cover type, and surrounding built environment all affected earthworm biomass. However, none of these residential variables significantly affected its community assemblage. Variation partitioning in canonical ordination revealed that edaphic properties, rather than landscapes, played a significant role in explaining the variation in its community assemblage, with an approximate contribution of 23%. The abundance and biomass of earthworms at the plot-scale in this study were consistent with previous studies at regional scales. However, the species richness at plot scale was lower than those at regional scale, suggesting that earthworm biodiversity may not accurately represent that at a larger scale, species-area relationship. The results indicate a shift in the driving factors of earthworm community assemblage from edaphic property variation at the plot scale to edaphic, historical, and biogeographical heterogeneities at the regional scale. Certain species that are sensitive to key edaphic/landscape parameters are potential candidates for monitoring soil ecological health.

Colistin and carbapenems, vital last-resort antibiotics against severe bacterial infections unresponsive to common drugs, pose a threat when resistance develops as it may leads to complete antibiotic ineffectiveness. The estimation and quantification of colistin and carbapenems in environmental samples is challenging due to their low concentrations, complex structures, stability issues, and potential interference from other substances. Despite known side-effects, the biological impacts of their residues recirculated in the environment has not yet been evaluated. This review provides an in-depth analysis of these two critical drugs by exploring their chemical and biological properties and current detection. This is based on 41 analytical studies on their quantitation methods, with 7 studies being from environmental matrices and the rest being from biological matrices. Reverse-phased chromatography and high-performance liquid chromatography tandem mass spectrometry are the main instruments due to their polar nature. We also discuss the growing challenges associated with their release into environmental settings. We focus on the environmental entry pathways of these antibiotic residues, as well as the development of resistance. These antibiotics primarily enter the environment through runoff from hospitals and agricultural sites, leading to their accumulation in wastewater, soil, and natural water bodies. This environmental exposure is particularly of concern due to the potential for resistance development. The spread of resistance genes is a complex process, often involving mechanisms like horizontal gene transfer, which are facilitated by the presence of these antibiotic residues in the environment. Further research is crucial in understanding the environmental release of these critical antibiotics, the analytical methods of their quantifycation in environmental settings, and their role in the dissemination of antimicrobial resistance.

Pharmaceutical compounds often coexist in mixtures rather than as individual entities. However, little is known about their co-adsorption and co-mobility in soil and groundwater. In this study, we investigated the adsorption of a quinolone antibiotic (nalidixic acid, NA) and an anti-inflammatory agent (niflumic acid, NFA) onto two soils from France and Sweden in water-saturated soil columns. Despite its lower hydrophobicity, adsorption of NA is much greater than NFA, which can be ascribed to the presence of both carbonyl and carboxylic groups in NA molecule. The data suggest that adsorption to soil components can mainly take place through hydrogen bonding and surface complexation mechanisms, prevailing over hydrophobic interactions. Accordingly, more sorption of NA and NFA was observed in the Swedish soil because it contains more clay content, and much higher Al and Fe contents than the French soil. Injection of NA/NFA mixture in the column did not modify the breakthrough behavior compared to single systems, although cooperative adsorption was observed under static batch conditions. Ca²⁺ inhibited NA adsorption by forming a soluble NA-Ca²⁺ complex but promoted NFA adsorption both in single and binary systems. The mobility in soil columns was well predicted using a new transport model that accounts for both kinetics and binding reactions of NA and NFA to soil constituents. This work will help in accurately predicting the mobility of coexisting pharmaceutical compounds in soils.

Soil health is the foundation of sustainable agriculture, and its preservation is paramount in global arsenic (As) contamination challenges. Soil As contamination is a critical issue for environmental and agricultural sustainability. Rapid global urbanization and agricultural and industrial expansion release toxic metal (loid)s including As into the soil. Arsenic contamination disrupts the rhizosphere ecosystem, affecting plant health, microbial communities, and overall soil functionality. Ensuring soil health in the face of As contamination is imperative for human well-being and for developing a resilient, sustainable environment. This review signifies the need for comprehensive strategies to revitalize soil ecosystems, promoting resilience and long-term ecological balance. Advanced biotechnological approaches, particularly bioremediation including phytoremediation, microbial remediation, mycoremediation, nano-remediation, and other integrative strategies, are highlighted for their effectiveness in addressing As contamination and promoting soil health. Conventional physico-chemical techniques make soil unsuitable for agriculture by disrupting the microenvironment. Consequently, the urgent need for remediation of As-contaminated soil demands the adoption of eco-friendly and sustainable approaches, such as bioremediation, phytoremediation, and rhizoremediation, to enhance soil health.

Development of transgenic lines and genetically modified organisms are effective tools in reducing the As burden. Bacteria including Sphingomonas desiccabilis, Bacillus subtilis and Bacillus idriensis expressing the arsM gene all show promising results to reduce the As burden. Transgenic rice, incorporating the arsM gene from Rhodopseudomonas palustris, demonstrated 10 times more volatile arsenicals and reduced As accumulation in the grain. Additionally, the use of As-hyperaccumulating plants and conventional methods, like chemical-assisted phytoextraction, show potential for decontaminating As- contaminated soil. Future research should explore the contributions of novel biotechnological strategies to enhance soil health in regions affected by As contamination.

Phytoremediation can be effective for the removal, immobilization, mineralization, and/or detoxification of various pollutants in soils and water, including inorganic and organic pollutants, and radioisotopes. Although the feasibility of phytoremediation has been proven in the last decades, its performance is uncertain due to the complex interactions among soil, water, plants, weather, microorganisms, and pollutants, leading to its underutilizing globally. This paper aims to review the representations and methods for quantifying key phytoremediation processes via modelling. We examine the structures, methods and ability of phytoremediation models that characterize the biogeochemical, hydrological, and phenological processes accountable for phytoremediation dynamics, along with discussions about their advantages and limitations. Then, we identify the knowledge gaps and challenges in incorporating biogeochemical, hydrological, and phenological processes into phytoremediation models in contaminated sites and representing spatial heterogeneity and temporal variability in large-scale applications. The existing phytoremediation models are difficult to predict the phytoremediation period under real environmental conditions but it is a key assessment of phytoremediation performance and cost. Finally, we explore the opportunities to integrate the current knowledge from other disciplines, such as soil, agriculture, ecology, and plant research in a competition-based model. We highlight the key research priorities for effective integration of knowledge based on physical, chemical, and biological processes in modelling phytoremediation, including biogeochemical processes, soil amendments and agro-practices. Further studies need to consider the immobilization, mineralization and detoxification processes of pollutants in contaminated sites.