Acid In Soil Research Articles

The Cd sequestration effects of rice roots affected by different Si management in Cd-contaminated paddy soil

The application of exogenous silicon (Si) reportedly is one of the eco-friendly practices to mitigate cadmium (Cd) phytotoxicity and regulate the chemical behaviors of Cd in the soil-rice system. But the efficiency of Si on the Cd retention by rice root varies with the Si fertilizer management. The objective of this paper was to interpret the differences in Cd immobilization by rice roots and relevant mechanisms under different ways of Si application (T-Si, supplied at transplanting stage; TJ-Si, split at transplanting and jointing stage with the ratio of 50 % to 50 %; J-Si, supplied at jointing stage and CK, none of Si application) in Cd-contaminated paddy soils. The results showed that the Cd-retention capacity of rice root was increased by 0.60 % ~ 3.06 % under different Si management when compared to CK. The concentrations of monosilicic acid in soils and in apoplast and symplast of roots were increased significantly by Si application, while Cd concentrations in apoplast and symplast of root were decreased by 28.50 % (T-Si), 40.64 % (TJ-Si) and 30.26 % (J-Si), respectively. The distribution of Cd in rice cell wall was increased significantly by TJ-Si. The Cd concentrations of inert fractions (F3, F4 and F6) in root of TJ-Si were raised obviously. Si application downregulated the expression of OsIRT2 and OsNramp5 while upregulated OsHMA3, and the expression of OsHMA3 treated by TJ-Si was obviously higher than CK and J-Si. The distributions of the passive Cd in roots bound with thiol compounds (NPT, GSH and PCs) and polysaccharide components (pectin, hemicelluloses 1 and hemicellulose 2) were raised much more by TJ-Si than by T-Si and J-Si. On the whole, compared with T-Si and J-Si, TJ-Si could more easily replenish soil available Si and enhance Cd sequestration in roots as the result of the decrease of Cd transport factor in roots. This study unravels some mechanisms about different Si management on increasing Cd retention and decreasing Cd migration in rice roots, and TJ-Si is worthy of being recommended.

Distribution of Molecular Weight of Humic Substances Isolated from Soils of Tallgrass Temperate Rainforests (Chernevaya Taiga)

The boreal forests of Russia are one of the largest forest areas on the planet. As a result of climate change, the rate of carbon sequestration and stabilization of organic matter are important indicators of environmental conservation. To understand mechanisms of stabilization and the structure of soil organic carbon, the molecular-weight (MW) distribution of humic acids (HAs) in soils of the central deciduous-forest zone of boreal forests (Chernevaya taiga, transitional ecotone forest, coniferous forest) was studied. Analysis of the MW distribution of HAs was conducted using size-exclusion chromatography. This approach allowed us to obtain the distribution of high-, medium-, and low-molecular fractions of HAs. It has been revealed that the content of the low-MW fraction prevails over the content of the medium- and high-MW fractions of HAs, which indicates the process of stabilization in soil organic matter. The accumulation of low-molecular-weight fraction occurs with the aromaticity increase in HAs, which indicates that HAs with a relatively high proportion of aromatic fragments have smaller hydrodynamic radius and a lower MW. It has been statistically substantiated that the low-molecular-weight fraction correlates with the content of aromatic compounds and carboxyl structural fragments of HAs, which indicates the resistance of the soil organic matter of Chernevaya taiga to biodegradation.

Ecological risk assessment for perfluorohexanesulfonic acid (PFHxS) in soil using species sensitivity distribution (SSD) approach

Perfluorohexanesulfonic acid (PFHxS) is one of the persistent organic pollutants that has been recommended to be listed in Annex A of the Stockholm Convention. It has gained increasing attention in recent years due to its toxic effects. The guideline values of PFHxS are commonly associated with PFOS in various countries and regulatory agencies. In this study, multispecies bioassays were conducted to determine the ecological toxic effects of PFHxS, including plants, soil invertebrates, and soil microorganisms, which indicated the EC10/NOEC values ranged from 2.9 to 250 mg/kg. Where possible, logistic models were used to calculate the EC30 values for various endpoints. The species sensitivity distributions were employed to estimate the ecological investigation levels for PFHxS contamination in soils using toxicity results from literature and this study. The calculation using EC10/NOEC values from both literature and this study indicated a most conservative HC5 as 1.0 mg/kg (hazardous concentration for 5 % of the species being impacted). However, utilisation of EC30 values derived from this study resulted in a much higher HC5 for PFHxS in contaminated soils (13.0 mg/kg) which is at the higher end of the existing guideline values for PFOS for protecting ecological systems. The results obtained in this study can be useful in risk assessment processes to minimize any uncertainty using combined values with PFOS.

Analytical derivatizations in environmental analysis

Analytical derivatization is a technique that alters the structure of an analyte and produces a product more suitable for analysis. While this process can be time-consuming and add reagents to the procedure, it can also facilitate the isolation of the analyte(s), enhance analytes’ stability, improve separation and sensitivity, and reduce matrix interferences. Since derivatization is a functional group analysis, it improves selectivity by separating reactive from neutral compounds during sample preparation. This technique introduces detector-orientated tags into analytes that lack suitable physicochemical properties for detection at low concentrations. Notably, many regulatory bodies, especially those in the environmental field, require these characteristics in analytical methods. This review focuses on note-worthy analytical derivatization methods employed in environmental analyses with functional groups, phenol, carboxylic acid, aldehyde, ketone, and thiol in aqueous, soil, and atmospheric sample matrices. Both advantages and disadvantages of analytical derivatization techniques are discussed. In addition, we discuss the future directions of analytical derivatization methods in environmental analysis and the potential challenges.

Responses of microbial communities and metabolic profiles to the rhizosphere of Tamarix ramosissima in soils contaminated by multiple heavy metals

Heavy metals (HMs) contamination around smelters poses serious stress to soil microbiome. However, the co-effect of multiple HMs and native vegetation rhizosphere on the soil ecosystem remains unclear. Herein, effects of high HMs level and the rhizosphere (Tamarix ramosissima) on soil bacterial community structure and metabolic profiles in sierozem were analyzed by coupling high-throughput sequencing and soil metabolomics. Plant roots alleviated the threat of HMs by absorbing and stabilizing them in soil. High HMs level decreased the richness and diversity of soil bacterial community and increased numbers of special bacteria. Plant roots changed the contribution of HMs species shaping the bacterial community. Cd and Zn were the main contributors to bacterial distribution in non-rhizosphere soil, however, Pb and Cu became the most important HMs in rhizosphere soil. HMs induced more dominant metal-tolerant bacteria in non-rhizosphere than rhizosphere soil. Meanwhile, critical metabolites varied by rhizosphere in co-occurrence networks. Moreover, the same HMs-tolerant bacteria were regulated by different metabolites, e.g. unclassified family AKYG1722 was promoted by Dodecanoic acid in non-rhizosphere soil, while promoted by Octadecane, 2-methyl- in rhizosphere soil. The study illustrated that high HMs level and rhizosphere affected soil properties and metabolites, by which soil microbial community structure was reshaped.

Extraction and GC-MS analysis of phenolic acids in rhizosphere soil of Pinellia ternate

In this paper, five phenolic acids in the rhizosphere soil of Pinellia ternate were determined to have strong allelopathy to Pinellia ternate. The phenolic acids in rhizosphere soil and non continuous cropping soil of Pinellia ternate for two years were extracted and detected by GC-MS, 5 phenolic acids were found to have different content changes. By comparing the contents of phenolic acids in the rhizosphere soil before, during and after planting, and combining with the literatures, it was determined that protocatechuic acid, vanillic acid, vanillin, syringate and syringaldehyde had strong allelopathy on the growth and development of Pinellia ternate. Furthermore, the effects of the above five phenolic acids on the growth of Pinellia ternate, the growth of seedlings and the comparison of tuber size were investigated. The results showed that the five phenolic acids had inhibitory effects on the growth of Pinellia ternate.

Plants can access limited amounts of nitrogen- and sulphur-containing amino acids in soil owing to rapid microbial decomposition

Plants can access limited amounts of nitrogen- and sulphur-containing amino acids in soil owing to rapid microbial decomposition

Solubilization of phosphorus by low molecular weight organic acids and amino acids in calcareous soils

In order for plants to perform well in nutrient-deficient calcareous soils, they have an efficient adaptive technique of root exudate secretion, which contains low molecular weight organic acids. They enhance nutrient release and thereby increase the nutrient availability in calcareous soils. The present study aimed to investigate the effect of concentration and time of incubation of low molecular weight organic acids on P solubilization from calcareous soils collected from various locations of Coimbatore district with varying levels of calcareousness. An incubation experiment was conducted with five calcareous soils with varying levels of free CaCO3 viz., (1, 7.5, 12.5, 17.5 & 21.5%) by incubating with seven different concentrations (0, 20, 40, 60, 80 & 100 mM) of four organic (citric, malic, oxalic and acetic acid) and two amino acids (glycine and lysine) for nine incubation time intervals (5, 10, 20, 30, 60, 120, 240, 960 & 1440 mins) on a factorial experiment based on completely randomized design (CRD). Available P was analyzed to find the solubilization efficiency of various organic and amino acids. The organic acids were more efficient when compared to amino acids in P solubilization, especially citric acid followed by oxalic and malic acids, at 100 mM concentration incubated for 1440 mins. Also, the solubilization increased with increasing concentration and incubation time, irrespective of the soil calcareousness, but the magnitude of phosphorus extraction decreased with increasing soil calcareousness. Incubating the calcareous soils with 100 mM of citric acid for 1440 min solubilized more amount of phosphorus. Hence it can be concluded that addition of 100 mM citric acid will influence the phosphorus release even from highly calcareous soils.

Study on Strength Development and Microstructure of Cement-Solidified Peat Soil Containing Humic Acid of Dianchi Lake

The disposal of peat soil poses an increasingly difficult problem for actual engineering projects of Dianchi Lake area. This study obtains peat soil from seven areas around Dianchi Lake, and the content of humic acid (HA) in peat soil is between 2.36% and 28.13%. Then, this study simulates the peat soil by adding HA into the cohesive soil and uses cement to solidify it. The effect of cement and HA on the strength development of samples is examined by the unconfined compressive strength (UCS) test. Additionally, the microstructures of typical mixes are analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and mercury intrusion porosimetry (MIP). The results showed that HA will significantly reduce the UCS of cement soil. The SEM, XRD, and MIP confirmed that cement hydration reaction increases with cement ratio. In addition to the cementitious soil particles, hydration products gradually fill the pores of the soil and effectively reduce the number of large-size (6000∼40,000 nm) pores in cement soil, which makes the soil particle framework stronger. When the cement ratio increases from 15% to 25%, the diffraction peak of CAH and CSH increases faster. Combined with the results of the UCS test, it could be proved that cement ratio greater than 20% weakens the influence of HA on the strength development of cement soil sample.

Study on Molecular Structure Model and Visualization of Humic Acids in Different Soils Based on Statistics

Study on Molecular Structure Model and Visualization of Humic Acids in Different Soils Based on Statistics

Long-Term Monocultures of American Ginseng Change the Rhizosphere Microbiome by Reducing Phenolic Acids in Soil

American ginseng (Panax quinquefolius L.) is an important cash crop, but long-term monoculture often results in serious root rot disease and yield reduction. The dynamics of soil phenolic acids perform an important function in soil microbe–plant interactions, but the extent to which changes in phenolic acids that occur under the continuous monoculture of American ginseng influence growth and the rhizosphere microbial community are unclear. In this study, American ginseng was planted in soil that had been used for 3 years of continuous monoculture (3 yr) and into a soil with no history of planting American ginseng (0 yr). Soil phenolic acids, rhizosphere microbiome characteristics, and pathogen suppression were analyzed. In the findings, the diversity and structure of the rhizosphere microbial community were affected by monoculture history, as the diversity of fungi and bacteria in 3 yr soil was higher than in 0 yr soil. The physiological performance of American ginseng in 3 yr soil was significantly lower than that in 0 yr soil. Soil phenolic acid contents decreased with the longer monoculture history, and high concentrations of phenolic acids suppressed the growth of American ginseng-specific pathogens. Soil phenolic acids appeared to modulate the pathogen population and the rhizosphere microbiome in American ginseng monocultures.

Isolation and identification of Bacillus vallismortis HSB-2 and its biocontrol potential against apple replant disease

To avoid the shortcomings of chemical fungicides currently used to control apple replant disease, in this study, HSB-2 was isolated from the rhizosphere soil of healthy apple trees, and in vitro experiments showed that it had an antagonistic effect on a variety of plant fungal pathogens, especially Fusarium oxysporum, Fusarium moniliforme, Fusarium proliferatum, and Fusarium solani. Its fermentation broth showed a significant inhibitory effect on the mycelial growth and spore germination of four Fusarium species. HSB-2 was identified as Bacillus vallismortis based on physiological and biochemical characteristics and molecular sequencing. HSB-2 produced diffusible and volatile organic compounds (VOCs) and showed good antifungal and growth-promoting properties. The pot experiment showed that HSB-2 had good colonization ability in the rhizosphere of Malus hupehensis Rehd. seedlings, and the disease index of seedlings inoculated with HSB-2 stabilized at 40, and the relative control effect reached 60% after 5 weeks. When 2.1 × 109 amount HSB-2 (at CFU·g−1) was added to the soil together with manure carrier (cow dung:straw = 3:1) (T2), it significantly increased the biomass of apple plant, the numbers of soil bacteria and actinomycetes, and activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) as well as soil enzymes, including urease, phosphatase, sucrose and CAT, and significantly reduced the content of phlorizin, benzoic acid, cinnamic acid, and p-hydroxybenzoic acid in soil. The results of T-RFLP and qPCR showed that T2 treatment significantly increased the carbon utilization level and Simpson index of bacteria, and decreased the abundance of four Fusarium species in soil, causing the bacterial and fungal community structures to differ significantly from those for other treatments. In conclusion, HSB-2 can protect apple plants from damage by four Fusarium species and phenolic acids, improve soil microbial community, increase soil enzyme activity, and promote plant growth. We thus propose the use of B. vallismortis HSB-2 as a biological control agent to control ARD.

Electron donating properties of humic acids in saltmarsh soils reflect soil geochemical characteristics

In saltmarsh soils, humic acids (HA) are involved in geochemically important redox processes. The electron donating capacity (EDC) of HA depends on their molecular structure, but also reflects the intensity of biological reduction in tidal environments. We examined twelve soils in three saltmarshes located along a geographical gradient and applied a specific sequential extraction procedure for the isolation of HA fractions bound (BHA) or not (FHA) to the mineral matrix by Ca2+ bridges, and investigated the relationships of their properties, in particular their EDC, with the biogeochemical characteristics of the soils. Spectroscopic assessment was carried out by UV–vis, FTIR and 13C NMR, quantification and characterization of radicals was performed by electron paramagnetic resonance (EPR) spectroscopy. The EDC was determined by using the 2,2′-azinobis-(3-ethylbenzothiazolinesulfonic acid) (ABTS) decolorization assay and experimental data were fitted to a biphasic model to calculate the contributions of the fast and slow reactions to electron transfer. The results confirmed that the two HA fractions possess different structural characteristics and that BHA present higher EDC values compared to FHA. The EDC of both fractions is strongly related to the geochemical characteristics of soils, and represents an easily measured and highly informative parameter to understand mechanisms affecting redox processes in transitional environments.

Determining the appropriate level of farmyard manure biochar application in saline soils for three selected farm tree species.

Salinity is a global problem, and almost more than 20% of the total cultivated area of the world is affected by salt stress. Phytoremediation is one of the most suitable practices to combat salinity and recently biochar has showed the tremendous potential to alleviate salt-affected soils and enhance vegetation. Trees improve the soil characteristics by facilitating the leaching of salts and releasing organic acids in soil. Moreover, in the presence of trees, higher transpiration rates and lower evaporation rates are also helpful in ameliorating salt affected soils. This study was designed to check the effect of different levels of biochar on the morph-physiological characteristics of three important agroforestry tree species: Eucalyptus camaldulensis, Vachellia nilotica, and Dalbergia sissoo, in saline soils. Farmyard manure biochar was applied at the rate of 3% (w/w), 6% (w/w), and 9% (w/w) to find appropriate levels of biochar for promoting the early-stage trees growth under saline conditions. Results of the current study revealed that maximum shoot length (104.77 cm), shoot dry weight (23.72 g), leaves dry weight (28.23 g), plant diameter (12.32 mm), root length (20.89 cm), root dry weight (18.90 g), photosynthetic rate (25.33 μ moles CO2 m-2s-1) and stomatal conductance (0.12 mol H2O m-2 s-1) were discovered in the plants of Eucalyptus camaldulensis at the rate of 6% (w/w). All tree species showed better results for growth and physiological characteristics when biochar was applied at the rate of 6% (w/w). In comparison, a decreasing trend in growth parameters was found in the excessive amount of biochar when the application rate was increased from 6% (w/w) to 9% (w/w) for all three species. So, applying an appropriate level of biochar is important for boosting plant growth in saline soils. Among different tree species, Vachellia nilotica and Eucalyptus camaldulensis both showed very promising results to remediate salt affected soils with Vachellia nilotica showing maximum potential to absorb sodium ions.

Effects of organic acids on heavy metal release or immobilization in contaminated soil

In order to explicit the environmental activity of heavy metals affected by different organic acids in soil, a batch incubation experiment was explored to investigate the influence of high relative molecular mass organic acid (HMWOA) (humic acid and fulvic acid) and low relative molecular mass organic acid (LMWOA) (threonic acid and oxalic acid) on the release or immobilization of Pb, Cu and Cd in soils. Results showed that LMWOA, especially threonic acid, had a good performance in the release of Pb, Cu and Cd from soils, and decrease in the fractions of HOAc-extractable, reducible and oxidable Pb, Cu and Cd. Conversely, HMWOA, especially humic acid, decreased the release of Pb, Cu and Cd, while it increased the fractions of HOAc-extractable, reducible and oxidable Pb, Cu and Cd, indicating that HMWOA can immobilize heavy metals. The release of Pb, Cu and Cd caused by LMWOA was attributed to the dissociation of soil organic matter and amorphous iron oxides since the total organic carbon and the water-soluble iron increased. The immobilization of Pb, Cu and Cd by HMWOA was attributed to the adsorption onto HMWOA followed by amorphous iron since HMWOA resulted in a significant decrease of zeta potential and an increase of amorphous iron oxide. It can be concluded that LMWOA has a potential application in soil washing remediation, while HMWOA can be used in the immobilization remediation for heavy metals contaminated soils.

Patterns of free amino acids in tundra soils reflect mycorrhizal type, shrubification, and warming

The soil nitrogen (N) cycle in cold terrestrial ecosystems is slow and organically bound N is an important source of N for plants in these ecosystems. Many plant species can take up free amino acids from these infertile soils, either directly or indirectly via their mycorrhizal fungi. We hypothesized that plant community changes and local plant community differences will alter the soil free amino acid pool and composition; and that long-term warming could enhance this effect. To test this, we studied the composition of extractable free amino acids at five separate heath, meadow, and bog locations in subarctic and alpine Scandinavia, with long-term (13 to 24 years) warming manipulations. The plant communities all included a mixture of ecto-, ericoid-, and arbuscular mycorrhizal plant species. Vegetation dominated by grasses and forbs with arbuscular and non-mycorrhizal associations showed highest soil free amino acid content, distinguishing them from the sites dominated by shrubs with ecto- and ericoid-mycorrhizal associations. Warming increased shrub and decreased moss cover at two sites, and by using redundancy analysis, we found that altered soil free amino acid composition was related to this plant cover change. From this, we conclude that the mycorrhizal type is important in controlling soil N cycling and that expansion of shrubs with ectomycorrhiza (and to some extent ericoid mycorrhiza) can help retain N within the ecosystems by tightening the N cycle.

The Phlorizin-Degrading Bacillus licheniformis XNRB-3 Mediates Soil Microorganisms to Alleviate Apple Replant Disease.

In this study, an endophytic phlorizin-degrading Bacillus licheniformis XNRB-3 was isolated from the root tissue of healthy apple trees, and its control effect on apple replant disease (ARD) and how it alleviates the pathogen pressure via changes in soil microbiomes were studied. The addition of strain XNRB-3 in Fusarium infested soils significantly reduced the number of pathogens in the soil, thus resulting in a lower disease incidence, and the relative control effect on Fusarium oxysporum reached the highest of 66.11%. The fermentation broth can also protect the roots of the plants from Fusarium oxysporum, Fusarium moniliforme, Fusarium proliferatum, and Fusarium solani infection. These antagonistic effects were further validated using an in vitro assay in which the pathogen control was related to growth and spore germination inhibition via directly secreted antimicrobial substances and indirectly affecting the growth of pathogens. The secreted antimicrobial substances were identified using gas chromatography-mass spectrometry (GC-MS) technology. Among them, alpha-bisabolol and 2,4-di-tert-butylphenol had significant inhibitory effects on many planted pathogenic fungi. Butanedioic acid, monomethyl ester, and dibutyl phthalate promoted root development of Arabidopsis plants. Strain XNRB-3 has multifarious plant growth promoting traits and antagonistic potential. In pot and field experiments, the addition of strain XNRB-3 significantly promoted the growth of plants, and the activity of enzymes related to disease resistance [superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)] was also significantly enhanced. It also reduced the abundance of four species of Fusarium and the content of phenolic acids in the rhizosphere soil, improved soil microbial community structure and nutritional conditions, and increased soil microbial diversity and activity, as well as the soil enzyme activity. The above results indicated that B. licheniformis XNRB-3 could be developed into a promising biocontrol and plant-growth-promoting agent.

Relationship between accumulation of autotoxins and soil fertility factors under long-term continuous cropping of cucumber in solar greenhouse

In this study, we investigated the effects of long-term continuous cucumber cropping on phenolic acids in rhizosphere soil, as well as their link to soil chemical characteristics, enzyme activities, and microbiological activities, using rhizosphere soil from the 2nd, 6th, 10th, 14th, 18th, 20th, 24th, and 26th round of cucumber cultivation in solar greenhouse. The results showed that contents of phenolic acids increased significantly with increasing continuous cropping rounds. The increase amount per round of total phenolic acid was significantly higher in the early stage (0-2 rounds) and late stage (20-26 rounds) than middle stage (10-14 rounds) of continuous cropping. Soil nutrient contents were enriched, while invertase enzyme activity and microbial activities were decreased. Redundancy analysis showed that organic matter, total phosphorus, total nitrogen, available nitrogen, microbial biomass carbon and microbial metabolic entropy were main soil fertility factors correlating with the accumulation of phenolic acids. Results of structural equation model showed that soil phosphorus enrichment directly led to the accumulation of phenolic acids, and that nitrogen enrichment indirectly facilitated the accumulation of phenolic acids by altering the activity of microorganisms. As a result, proper nitrogen and phosphorus fertilizers application would reduce the accumulation of phenolic acids and alleviate the cucumber continuous cropping obstacles.

The Content of Benzoic Acid in Podzolic Soil and Its Sorption on Montmorillonite

The Content of Benzoic Acid in Podzolic Soil and Its Sorption on Montmorillonite

Removal and magnetic recovery of heavy metals and pesticides from soil by layered double hydroxides modified biotite

• Novel three-dimensional magnetic adsorbent by biotite supported LDHs. • High removal efficiency of heavy metals and pesticides by LDH@Bt from soil. • Removal mechanism of precipitation for Cu/Pb and surface adsorption for pesticide. • Favorable interception function of LDH@Bt in soil by column leaching experiments. • Admirable magnetic recovery ability to avoid potential contamination. Novel biotite (Bt) supported different amounts of Mg-Al layered double hydroxide (LDH@Bt) with a three-dimensional hierarchical structure was fabricated via in-situ growth method. The structural and morphology characterization indicate that LDHs stably and uniformly dispersed on Bt surface, but excessive LDHs still lead to obvious aggregation of LDHs. The removal performance of LDH@Bt for heavy metal of Cu 2+ /Pb 2+ and pesticides of glyphosate (GLY)/2-methyl-4-chlorophenoxyacetic acid (MCP) in soil was investigated, and the removal rates of LDH@Bt composite for four contaminants were higher than those of LDHs and Bt. Intraparticle diffusion and pseudo-second-order model well described the kinetics of heavy metals and pesticides removal. Adsorption isotherm data of Cu 2+ and Pb 2+ yielded better accordance of Freundlich model, while data of GLY and MCP were fitted Langmuir model well. In addition, different adsorption mechanisms for removal of Cu 2+ /Pb 2+ by precipitation and removal of GLY/MCP by surface adsorption were proposed. The application performance and recovery ability of LDH@Bt composite in soil were evaluated by column leaching experiments and magnetic collectability tests. The excellent removal performance and magnetic collectability provided a promising strategy for remediation and elimination of heavy metals and pesticides contaminations from soil.