Heavy metals and potential health risk assessment of Lactuca sativa and Daucus carrota from soil treated with organic manures and chemical fertilizer.

The large-scale production of food crops with heavy application of chemical fertilizers in the effort to meet the astronomical increase in food demands may be counterproductive to the goal of food security. This study investigated the effect of different soil treatments on the levels of heavy metals (Cr, Cu, Fe, Ni, Pb, and Zn) in two types of vegetables Lactuca sativa (lettuce) and Daucus carrota (carrot). The potential carcinogenic and non-carcinogenic health risks from their consumption were also evaluated. Planting experiment was set up in a randomized block design, with different soil treatments of soil + cow dung (CD), soil + sewage sludge (SS), soil + chemical fertilizer (nitrogen-phosphorus-potassium (NPK)), and untreated soil (UNTRD). The vegetables were harvested at maturity, washed with distilled water, and subjected to an acid digestion process before the levels of heavy metals were measured by inductively coupled plasma spectrometry (ICP-MS). The mean concentrations of the metals in the vegetables across all treatments were below the maximum permissible limits. The pattern of heavy metal accumulation by the vegetables suggested that the lettuce from SS treatment accumulated higher concentrations of heavy metals like Cr (0.20 mg/kg), Cu (3.91 mg/kg), Ni (0.33 mg/kg), and Zn (20.44 mg/kg) than carrot, with highest concentrations of Fe (90.89 mg/kg) and Pb (0.16 mg/kg) recorded in lettuce from NPK treatment. The bioaccumulation factor (BAF) showed that lettuce, a leafy vegetable, has bioaccumulated more heavy metals than carrot, a root vegetable. The BAF was generally below the threshold value of 1 in both vegetables, except in lettuce from NPK and CD treatments and carrot from NPK treatments, with BAF values of 1.6, 1.69, and 1.39, respectively. The cancer risk assessment factors were well below the unacceptable maximum range of 10-4 suggesting that consuming these vegetables might not expose an individual to potential risk of cancer development. The hazard quotient estimations were below the threshold values of 1 for all heavy metals; however, the hazard index (HI) values of 1.27 and 1.58 for lettuce from NPK and SS treatments indicate a potential non-carcinogenic health risk to consumers from intake of all the heavy metals.

Impact of historical soil management on the interaction of plant-growth-promoting bacteria with maize (Zea mays L.).

Edaphic factors can modulate the effects of microbial inoculants on crop yield promotion. Given the potential complexity of microbial inoculant responses to diverse soil management practices, we hypothesize that sustainable management of soil and water irrigation may improve soil quality and enhance the effects of plant growth-promoting bacteria (PGPB). Consequently, the primary objective was to assess the effectiveness of microbial inoculants formulated with Herbaspirillum seropedicae (Hs) and Azospirillum brasilense (Ab) on maize growth in soils impacted by different historical conservation management systems. We evaluated two soil management systems, two irrigation conditions, and four treatments: T0 - without bioinoculant and 100% doses of NPK fertilization; T1 - Hs + humic substances and 40% of NPK fertilization; T2 - Ab and 40% of NPK fertilization; T3 - co-inoculation (Hs + Ab) and 40% of NPK fertilization. Using a reduced fertilization dose (40% NPK) associated with microbial inoculants proved efficient in increasing maize shoot dry mass : on average, there was a 16% reduction compared to the treatment with 100% fertilization. In co-inoculation (Hs + Ab), the microbial inoculants showed a mutualistic effect on plant response, higher than isolate ones, especially increasing the nitrogen content in no-tillage systems irrigated by swine wastewater. Under lower nutrient availability and higher biological soil quality, the microbial bioinputs positively influenced root development, instantaneous water use efficiency, stomatal conductance, and nitrogen contents.

Urea promoted soil microbial community and reduced the residual ciprofloxacin in soil and its uptake by Chinese flowering cabbage.

Antibiotics in agricultural soil can be accumulated in crops and might pose a potential risk to human health. Nevertheless, there is a lack of knowledge about the impact of nitrogen fertilizers on the dissipation and uptake of antibiotics in soils. Therefore, our aim in this study is to investigate the effects of urea fertilizer on the residues of ciprofloxacin and its uptake by Chinese flowering cabbage (Brassica parachinensis L.) as affected by the associated changes on the soil microbial community. A pot experiment has been conducted using spiked soil with 20 mg ciprofloxacin /kg soil and fertilized with urea at dosages equal to 0, 0.2, 0.4, 0.8 t/ha. Application urea especially at 0.4 t/ha decreased the residue of ciprofloxacin in the soil and its uptake by the roots and its translocation to the shoots of Chinese flowering cabbage. The translocation factors (TFs) for ciprofloxacin were significantly decreased (P < 0.05) only at the treatment of 0.4 t/ha, while no significant difference of bio-concentration factors (BCFs). The average well color development (AWCD) values, Shannon diversity, and richness index were higher in the fertilized than the un-fertilized soils, and all such indicators were greater at the treatment of 0.4 t/ha than at 0.2 and 0.8 t/ha. The carbon substrate utilization of phenolic acids at the treatments of 0.4 t/ha were greater than with other levels of urea fertilizer. In conclusion, moderate urea addition significantly increased soil microbial activity and abundance, which in turn promoted the ciprofloxacin dissipation in soil and plant tissue. The present study provides an economical and operational strategy for the remediation of ciprofloxacin contaminated soils.

Chemical attributes, bacterial community, and antibiotic resistance genes are affected by intensive use of soil in agro-ecosystems of the Atlantic Forest, Southeastern Brazil.

Soil is one of the largest reservoirs of microbial diversity in nature. Although soil management is vital for agricultural purposes, intensive practices can have a significant impact on fertility, microbial community, and resistome. Thus, the aim of this study was to evaluate the effects of an intensive soil management system on the chemical attributes, composition and structure of prevalent bacterial communities, and presence and abundance of antimicrobial resistance genes (ARGs). The chemical characterization, bacterial diversity and relative abundance of ARGs were evaluated in soils from areas of intensive vegetable cultivation and forests. Results indicate that levels of nutrients and heavy metals were higher in soil samples from cultivated areas. Similarly, greater enrichment and diversity of bacterial genera was detected in agricultural areas. Of the 18 target ARGs evaluated, seven were detected in studied soils. The oprD gene exhibited the highest abundance among the studied genes and was the only one that showed a significantly different prevalence between areas. The oprD gene was identified only from soil of the cultivated areas. The blaSFO, erm(36), oprD and van genes, in addition to the pH, showed greater correlation with in soil of cultivated areas, which in turn exhibited higher contents of nutrients. Thus, in addition to changes in chemical attributes and in the microbial community of the soil, intensive agricultural cultivation systems cause a modification of its resistome, reinforcing the importance of the study of antimicrobial resistance in a One Health approach.

Effects of pasture intensification and sugarcane cultivation on non-target species: A realistic evaluation in pesticide-contaminated mesocosms.

Conventional soil management in agricultural areas may expose non-target organisms living nearby to several types of contaminants. In this study, the effects of soil management in extensive pasture (EP), intensive pasture (IP), and sugarcane crops (C) were evaluated in a realistic-field-scale study. Thirteen aquatic mesocosms embedded in EP, IP, and C treatments were monitored over 392 days. The recommended management for each of the areas was simulated, such as tillage, fertilizer, pesticides (i.e. 2,4-D, fipronil) and vinasse application, and cattle pasture. To access the potential toxic effects that the different steps of soil management in these areas may cause, the cladoceran Ceriophania silvestrii was used as aquatic bioindicator, the dicot Eruca sativa as phytotoxicity bioindicator in water, and the dipteran Chironomus sancticaroli as sediment bioindicator. Generalized linear mixed models were used to identify differences between the treatments. Low concentrations of 2,4-D (<97 µg L-1) and fipronil (<0.21 µg L-1) in water were able to alter fecundity, female survival, and the intrinsic rate of population increase of C. silvestrii in IP and C treatments. Similarly, the dicot E. sativa had germination, shoot and root growth affected mainly by 2,4-D concentrations in the water. For C. sancticarolli, larval development was affected by the presence of fipronil (<402.6 ng g-1). The acidic pH (below 5) reduced the fecundity and female survival of C. silvestrii and affected the germination and growth of E. sativa. Fecundity and female survival of C. silvestrii decrease in the presence of phosphorus-containing elements. The outcomes of this study may improve our understanding of the consequences of exposure of freshwater biota to complex stressors in an environment that is rapidly and constantly changing.

A comparative analysis of soil physicochemical properties and microbial community structure among four shelterbelt species in the northeast China plain.

Conducting studies that focus on the alterations occurring in the soil microbiome within protection forests in the northeast plain is of utmost importance in evaluating the ecological rehabilitation of agricultural lands in the Mollisols region. Nevertheless, the presence of geographic factors contributes to substantial disparities in the microbiomes, and thus, addressing this aspect of influence becomes pivotal in ensuring the credibility of the collected data. Consequently, the objective is to compare the variations in soil physicochemical properties and microbial community structure within the understory of diverse shelterbelt species. In this study, we analyzed the understory soils of Juglans mandshurica (Jm), Fraxinus mandschurica (Fm), Acer mono (Am), and Betula platyphylla (Bp) from the same locality. We employed high-throughput sequencing technology and soil physicochemical data to investigate the impact of these different tree species on soil microbial communities, chemical properties, and enzyme activities in Mollisols areas. Significant variations in soil nutrients and enzyme activities were observed among tree species, with soil organic matter content ranging from 49.1 to 67.7 g/kg and cellulase content ranging from 5.3 to 524.0 µg/d/g. The impact of tree species on microbial diversities was found to be more pronounced in the bacterial community (Adnoism: R = 0.605) compared to the fungal community (Adnoism: R = 0.433). The linear discriminant analysis effect size (LEfSe) analysis revealed a total of 5 (Jm), 3 (Bp), and 6 (Am) bacterial biomarkers, as well as 2 (Jm), 6 (Fm), 4 (Bp), and 1 (Am) fungal biomarker at the genus level (LDA3). The presence of various tree species was observed to significantly alter the relative abundance of specific microbial community structures, specifically in Gammaproteobacteria, Ascomycota, and Basidiomycota. Furthermore, environmental factors, such as pH, total potassium, and available phosphorus were important factors influencing changes in bacterial communities. We propose that Fm be utilized as the primary tree species for establishing farmland protection forests in the northeastern region, owing to its superior impact on enhancing soil quality. IMPORTANCE: The focal point of this study lies in the implementation of a controlled experiment conducted under field conditions. In this experiment, we deliberately selected four shelterbelts within the same field, characterized by identical planting density, and planting year. This deliberate selection effectively mitigated the potential impact of extraneous factors on the three microbiomes, thereby enhancing the reliability and validity of our findings.

The influence of a soil amendment on the abundance and interaction of arbuscular mycorrhizal fungi with arable soils and host winter wheat.

Arbuscular mycorrhizal (AM) fungi have been shown to be associated with an estimated 70 % of vascular terrestrial plants. Such relationships have been shown to be sensitive to soil disturbance, for example, tillage in the preparation of a seed bed. From the application of arable soil management, AM fungal populations have been shown to be negatively impacted in abundance and diversity, reducing plant growth and development. The present study aims to utilise two sources (multipurpose compost and a commercial inocula) of mycorrhizal fungi for the amendment of arable soils supporting Zulu winter wheat under controlled conditions and quantify plant growth responses. A total of nine fields across three participating farms were sampled, each farm practicing either conventional, reduced, or zero tillage soil management exclusively. Soil textures were assessed for each sampled soil. Via the employment of AM fungal symbiosis quantification methods, AM fungi were compared between soil amendments and their effects on crop growth and development. The present study was able to quantify a mean 6 cm increase to crop height (P<0.001), 10 cm reduction to root length corresponding with a 2.45-fold increase in AM fungal arbuscular structures (P<0.001), a 1.15-fold increase in soil glomalin concentration corresponding to a 1.26-fold increase in soil carbon, and a 1.32-fold increase in the relative abundance of molecular identified AM fungal sequences for compost amended soils compared to control samples. Mycorrhizal inocula, however, saw no change to crop height or root length, AM fungal arbuscules were reduced by 1.43-fold, soil glomalin was additionally reduced by 1.55-fold corresponding to a reduction in soil carbon by 1.31-fold, and a reduction to relative AM fungal species abundance by 1.26-fold. The present study can conclude the addition of compost as an arable soil amendment is more beneficial for the restoration of AM fungi beneficial to wheat production and soil carbon compared to the addition of a commercial mycorrhizal inocula.

Flooding by sea and brackish waters enhances mobility of Cd, Zn and Pb from airborne dusts in coastal soils.

Sea level rise and extreme weather conditions caused by climatic changes enhance the frequency and length of submersion events in coastal soils, causing deposited airborne dusts to get in contact with marine salts. The behaviour of Cd, Zn and Pb from pedogenetic minerals and from dusts from mining and smelting activities, added to two soils under different agricultural management (arable and grassland) was examined after soil flooding for 1, 7 and 30 days with waters of increasing salinities (0, 4.37, 8.75, 17.25 and 34.5 g L-1). A rain water event following 1 d flooding released an extra amount of metals. Concentration of potentially toxic elements (PTE), pH, dissolved inorganic and organic C were measured in solutions collected by gravity from soil columns. Speciation distribution of leached metals and oversaturation parameters were calculated by Visual Minteq 3.0 and showed that complexation by chloride ions for Cd and fulvic acids for Pb were the drivers of solubilisation, while Zn interacted with both. Results showed that marine salts enhance up to 300 times leaching of Cd, and several times that of Zn and Pb from contaminated soils and that airborne toxic elements are much more mobilized than pedogenic ones. Smelter exhaust metals, particularly Pb, were made more mobile than those in mine tailings (up to 55 against 0.7 ng µg-1 Pb). Soil management strongly also influence mobilization by saline water: much lower amounts were leached from the grassland soil. Soil organic matter quality (DOC and humification) affects the extent of mobilization. The length of the flooding period did not result in coherent time trend patterns for the three metals, probably because of the multiple changes in solution parameters, but leached metals were always highly linearly correlated negatively with pH and positively with DOC.

Spatial variability of chemical indicators of Amazon agricultural soils through geomultivariate statistics, Brazil.

This work focuses on evaluating the spatial variability of chemical attributes of soils under different agricultural use and native forest, indicating which are the possible indicator attributes of changes in environmental, through the use and management of the soil. The study was carried out in the southern region of the Amazonas state, in an Argissolo Vermelho-Amarelo (Ultisol). Sampling grids were established measuring: 90 m × 70 m with regular soil collection spacing of 10 m for the guarana and forest areas; 90 m × 56 m spaced at 10 m × 8 m for annatto area; and 54 m × 42 m with spacing between points of 6 m for the cupuaçu area, totaling 80 sampling points in each area, with soil samples collected at depths of 0.0-0.05; 0.05-0.10 m and 0.10-0.20 m. The following attributes were determined: pH, Al3+, K+, Ca2+, Mg2+, P, H + Al, CEC, V% and m%. Descriptive, geostatistical and multivariate statistical analyzes were performed. The results show that it is possible to state that the descriptive, geostatistical and multivariate statistical techniques were able to identify the difference between the spatial variability of the attributes according to each specific use of individual soils. The multivariate analysis made it possible to select the attributes that most contribute to the variability of these soils, and with that, it was found that the forest showed less spatial variability in the surface layer, with higher reach values by scaled semivariograms.

Multivariate Exploratory Analysis of the Bulgarian Soil Quality Monitoring Network.

The goal of the present study is to assess the soil quality in Bulgaria using (i) an appropriate set of soil quality indicators, namely primary nutrients (C, N, P), acidity (pH), physical clay content and potentially toxic elements (PTEs: Cu, Zn, Cd, Pb, Ni, Cr, As, Hg) and (ii) respective data mining and modeling using chemometrical and geostatistical methods. It has been shown that five latent factors are responsible for the explanation of nearly 70% of the total variance of the data set available (principal components analysis) and each factor is identified in terms of its contribution to the formation of the overall soil quality-the mountain soil factor, the geogenic factor, the ore deposit factor, the low nutrition factor, and the mercury-specific factor. The obtained soil quality patterns were additionally confirmed via hierarchical cluster analysis. The spatial distribution of the patterns throughout the whole Bulgarian territory was visualized via the mapping of the factor scores for all identified latent factors. The mapping of identified soil quality patterns was used to outline regions where additional measures for the monitoring of the phytoavailability of PTEs were required. The suggested regions are located near to thermoelectric power plants and mining and metal production facilities and are characterized by intensive agricultural activity.

Different Weed Managements Influence the Seasonal Floristic Composition in a Super High-Density Olive Orchard.

Weed management is not yet environmentally, agronomically, economically and socially sustainable in olive orchards. It is necessary to study appropriate integrated weed management systems (IWMSs) based on the knowledge of weed population and effects of weeding practices over time. The aim of this study was to evaluate the effects of different weed managements on seasonal floristic composition of a super high-density olive orchard, also exploiting the essential principles of an IWMS. Five weeding techniques were compared: chemical control (CHI), mowing (MEC), plastic (nonwoven tissue, TNT and polyethylene, PEN) and organic (with de-oiled olive pomace, DOP) mulching. Weed monitoring was carried out on six dates in a three-year period. The infestation of each of the main 18 weed species recorded (%) and the total infestation (%) on each monitoring date were determined. Results underlined that all weeding practices investigated in this multi-year study affected the floristic composition, weed characteristics (hemicryptophytes, cryptophytes and therophytes) and seed bank. TNT and PEN were the most effective methods for weed management. Particularly, total infestation coefficient was significantly lowest when plots were managed with TNT (13.91%) and PEN (14.38%) and highest for MEC (141.29%). However, DOP also significantly reduced infestation compared to CHI and MEC. Therefore, DOP could constitute an excellent strategy for weed management in super high-density olive groves, since it also has the possibility of distributing mulching materials in a mechanized way in field and can result in improvement of soil fertility and the possibility of valorizing waste. Further studies should be carried out to investigate the mechanism of action (physical and allelochemical) of de-oiled pomace or other organic agro-industrial materials and the recovery time of these mulching materials in super high-density olive orchards.

Effects of grazing prohibition on nirK- and nirS-type denitrifier communities in salt marshes.

Introduction: Grazing prohibition is an effective management practice to restore salt marsh functioning. However, the effects of grazing exclusion on denitrifying microbial communities and their controlling factors in salt marshes remain unclear. Methods: In this study, we surveyed soil physicochemical properties and above- and below-ground biomass and using quantitative polymerase chain reaction and Illumina MiSeq high-throughput sequencing technology to determine the relative abundance, composition, and diversity of nitrite reductase nirS- and nirK-type denitrifying bacterial communities associated with grazing prohibition treatments and elevations. Results: The abundance of nirS-type denitrifiers increased with grazing prohibition time, whereas the abundance of nirK-type denitrifiers remained unaltered. Moreover, nirS-type denitrifiers were more abundant and diverse than nirK-type denitrifiers in all treatments. Grazing prohibition significantly altered the operational taxonomic unit richness, abundance-based coverage estimator, and Chao1 indices of the nirS-type denitrifying bacterial communities, whereas it only minimally affected the structure of the nirK-type denitrifying bacterial community. Discussion: The results imply that the nirS community, rather than nirK, should be the first candidate for use as an indicator in the process of salt marsh restoration after grazing prohibition. Substances of concern, total nitrogen, and salinity were the key environmental factors affecting the abundance and community composition of nirS and nirK denitrifiers. The findings of this study provide novel insights into the influence of the length of grazing prohibition and elevation on nirS- and nirK-type denitrifying bacterial community composition in salt marshes.

Towards a farmer-feasible soil health assessment that is globally applicable.

Globally, agriculture has had a significant and often detrimental impact on soil. The continued capacity of soil to function as a living ecosystem that sustains microbes, plants, and animals (including humans), its metaphorical health, is of vital importance across geographic scales. Healthy soil underpins food production and ecosystem resilience against a changing climate. This paper focuses on assessing soil health, an area of increasing interest for farming communities, researchers, industry and policy-makers. Without accessible and reliable soil assessment, any management and interventions to improve soil health are likely to be sub-optimal. Here we explore available soil health assessments (SHAs) that may be feasible for farmers of varying income levels and suitable for broad geographic application. Whilst there is a range of existing approaches to SHA, we find that no one framework currently meets these broad aims. Firstly, reliance on expensive and logistically complex laboratory methods reduces viability and accessibility for many farmers. Secondly, lack of defined indicator baselines and associated thresholds or gradients for soil health prevents the assessment of soil measurements against achieving optima for a given set of local soil-climate conditions. Since soils vary greatly, these baselines and thresholds must be defined considering the local biogeographic context; it is inappropriate to simply transfer calibrated information between contexts. These shortcomings demand progress towards a feasible, globally applicable and context-relevant SHA framework. The most feasible SHAs we identified were developed locally in conjunction with farmers, who have been repeatedly found to assess the health of their soils accurately, often using relatively simple, observable indications. To progress, we propose assessment of which indicators add information to a SHA in local contexts, with a focus on sufficiency, to reduce data burden. Provision of a standardised protocol for measurement and sampling that considers the reliability and accuracy of different methods would also be extremely valuable. For greatest impact, future work should be taken forward through a cross-industry collaborative approach involving researchers, businesses, policy makers, and, above all, farmers, who are both experts and users.

Soil C dynamics after deforestation and subsequent conversion of arable cropland to grassland in humid temperate areas.

Land use and plant-soil management influence soil organic C stocks and soil properties. This study aimed to identify the main mechanisms by which these factors alter soil organic matter (SOM) dynamics and stocks. Changes in the organic C pools and biochemical quality in different OM compartments were assessed: a) after deforestation and intensive cultivation (SOM loss) and then, b) after the conversion of cropland to grassland (SOM replenishment) in a chronosequence of recovery (1-45 years). Topsoil samples were subjected to physical fractionation to assess the distribution of free particulate OM (POM) and mineral associated OM (MAOM). SOM quality was characterized by 13C NMR spectroscopy, thermal analysis (DSC/TG), and microbial activity was monitored by isothermal microcalorimetry. Deforestation and intensive cultivation led to the loss of 80 % of the C stored in the upper mineral soil (up to 30-35 cm). The POM was almost depleted, MAOM underwent significant losses (>40 %) and all OM compounds, including the aromatic C, were affected. The large and unexpected loss of MAOM can be attributed to the low specific surface soil area and also to the labile (biodegradable) nature of the OM in this fraction. After 45 years, conversion of cropland to grassland recovered 68 % of the C lost in the mineral soil (mainly as MAOM), at an annual rate of 1.25 Mg C ha-1. The present findings showed that the persistence of long-term OM depends on how strongly organic compounds are adsorbed onto mineral surfaces (i.e., the specific surface area) and the biochemical nature of OM compounds. Adequate plant-soil management favoured the replenishment of the MAOM under these experimental conditions, and this fraction was an active pool in terms of C storage and biochemical quality. This study served to test current theories about changes in soil C fractions due to land use changes and soil-plant management.

Molecular composition and possible transformations of labile soil organic matter fractions in Mediterranean arable soils: Relevance and implications.

With the increased global interest in sequestering carbon in soil, it is necessary to understand the composition of different pools of soil organic matter (SOM) that cycle over suitably short timeframes. To explore in detail the chemical composition of agroecologically relevant yet distinct fractions of SOM, the light fraction of SOM (LFOM), the 53-µm particulate organic matter (POM), and the mobile humic acid (MHA) fractions were sequentially extracted from agricultural soils and characterized using both 13C cross polarization magic angle spinning nuclear magnetic resonance (CPMAS NMR) spectroscopy and also Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The NMR results showed a decrease in the O-alkyl C region assigned to carbohydrates (51-110 ppm) and an increase in the aromatic region (111-161 ppm) proceeding from the LFOM to the POM and then to the MHA fraction. Similarly, based on the thousands of molecular formulae assigned to the peaks detected by FT-ICR-MS, condensed hydrocarbons were dominant only in the MHA, while aliphatic formulae were abundant in the POM and LFOM fractions. The molecular formulae of the LFOM and POM were mainly grouped in the high H/C lipid-like and aliphatic space, whereas a portion of the MHA compounds showed an extremely high (17-33, average of 25) double bond equivalent (DBE) values, corresponding to low H/C values of 0.3-0.6, representative of condensed hydrocarbons. The labile components appeared most pronounced in the POM (93% of formulae have H/C ≥ 1.5) similar to the LFOM (89% of formulae have H/C ≥ 1.5) but in contrast to the MHA (74% of formulae have H/C ≥ 1.5). The presence of both labile and recalcitrant components in the MHA fraction suggests that the stability and persistence of soil organic matter is influenced by a complex interaction of physical, chemical, and biological factors in soil. Understanding the composition and distribution of different SOM fractions can provide valuable insights into the processes that govern carbon cycling in soils, which can help inform strategies for sustainable land management and climate change mitigation.

Remediation of pesticide residues using ozone: A comprehensive overview.

Pesticide residues historically represent a severe threat to public health and the environment. Several species worldwide are still in danger from pesticide residues, despite efforts to mitigate the adverse health effects of these pollutants. As agricultural output has increased and scientific understanding has advanced, new methods have emerged for degrading pesticide traces. The remarkable effectiveness of ozone as a broad-spectrum disinfectant and its potential to destroy pesticide residues have led to its widespread use as a residue-free method for improving soil quality, disinfecting food, and treating water, among other benefits. Ozone is cheap to manufacture, making it an affordable option for treating harmful pesticide residues. Its capacity to degrade pesticides without negatively impacting the environment has increased its adoption as a tool for cleaning up after pesticide use. This review extensively provides an overview of ozonation for pesticide residues removal in different settings and applications. Ozone treatment of pesticide residues in the soil, water and food is effective in removing pesticides residues. We highlight recent advances in methods of removing pesticide residues. We discuss several challenges related to the ozone treatment of pesticide residues. Whether used alone or in conjunction with other processes, ozone is highly effective at removing pesticide residues from the environment. Therefore, we recommend this holistic and environmentally friendly strategy to reduce pesticide residues.

When biochar is involved in rhizosphere dissipation and plant absorption of pesticides: A meta-analysis.

Clarifying the influences of biochar input on the rhizosphere dissipation and plant absorption of pesticides is a crucial prerequisite for utilizing biochar in the restoration of pesticide-contaminated soils. Nevertheless, the application of biochar to pesticide-contaminated soils does not always achieve consistent results on the rhizosphere dissipation and plant absorption of pesticides. Under the new situation of vigorously promoting the application of biochar in soil management and carbon sequestration, a timely review is needed to further understand the key factors affecting biochar remediation of pesticide-contaminated soil. In this study, a meta-analysis was conducted utilizing variables from three dimensions of biochar, remediation treatment, and pesticide/plant type. The pesticide residues in soil and the pesticide uptake by plant were used as response variables. Biochar with high adsorption capacity can impede the dissipation of pesticides in soil and mitigate their absorption by plants. The specific surface area of biochar and the type of pesticide are critical factors that affect pesticide residues in soil and plant uptake, respectively. Applying biochar with high adsorption capacity, based on specific dosages and soil characteristics, is recommended for the remediation of continuously cultivated soil contaminated with pesticides. This article aims to provide a valuable reference and understanding for the application of biochar-based soil remediation technology and the treatment of pesticide pollution in soil.

The role of soil temperature in mediterranean vineyards in a climate change context.

The wine sector faces important challenges related to sustainability issues and the impact of climate change. More frequent extreme climate conditions (high temperatures coupled with severe drought periods) have become a matter of concern for the wine sector of typically dry and warm regions, such as the Mediterranean European countries. Soil is a natural resource crucial to sustaining the equilibrium of ecosystems, economic growth and people's prosperity worldwide. In viticulture, soils have a great influence on crop performance (growth, yield and berry composition) and wine quality, as the soil is a central component of the terroir. Soil temperature (ST) affects multiple physical, chemical and biological processes occurring in the soil as well as in plants growing on it. Moreover, the impact of ST is stronger in row crops such as grapevine, since it favors soil exposition to radiation and favors evapotranspiration. The role of ST on crop performance remains poorly described, especially under more extreme climatic conditions. Therefore, a better understanding of the impact of ST in vineyards (vine plants, weeds, microbiota) can help to better manage and predict vineyards' performance, plant-soil relations and soil microbiome under more extreme climate conditions. In addition, soil and plant thermal data can be integrated into Decision Support Systems (DSS) to support vineyard management. In this paper, the role of ST in Mediterranean vineyards is reviewed namely in terms of its effect on vines' ecophysiological and agronomical performance and its relation with soil properties and soil management strategies. The potential use of imaging approaches, e.g. thermography, is discussed as an alternative or complementary tool to assess ST and vertical canopy temperature profiles/gradients in vineyards. Soil management strategies to mitigate the negative impact of climate change, optimize ST variation and crop thermal microclimate (leaf and berry) are proposed and discussed, with emphasis on Mediterranean systems.

High-resolution risk mapping of heavy metals in soil with an integrated static-dynamic interaction model: A case study in an industrial agglomeration area in China.

Heavy metal pollution of soils in industrial agglomeration areas is an increasing concern worldwide. In this study, we traced the sources of heavy metal emissions using a positive matrix factorization (PMF) model. Accordingly, we proposed a novel static-dynamic risk interaction model incorporating multiple risk-related factors to quantify the spatial interaction of emission sources and the probability of accumulation of heavy metals on a large scale. This model was further classified using the Jenks optimization technique to predict the spatial distribution of high-risk hotspots. Our results determined four primary emission sources of heavy metals: industrial (35.01 %), natural (28.61 %), agricultural (26.07 %), and traffic (10.31 %) sources. Five levels were classified by the integrated risk coefficient (IRC), namely, from extremely high to extremely low risk. The extremely high- and high-risk hotspots constituting 41.52 % of the total area of the Zhenhai District, with IRC values ranging from 0.221 to 0.413, were mainly generated by multiple sources linked to PMF-based factors. This quantitative evaluation framework can generate a high-resolution spatially distributed pollution risk map at the grid scale (1 km), which can provide a relatively precise basis for policymaking for point-to-point soil pollution management.