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A field experiment was performed with the aim to assess the amount of penconazole losses during field application and the spatial variability of penconazole concentration in a vineyard soil, under two different management techniques (tilled and grass covered). The field dissipation of penconazole under the two techniques was also followed for 114 days, highlighting the effects of spatial variability of the initial concentration and of the grass covering in terms of the different soil metabolic activity. Data found show that a high percentage of penconazole, from 42.5 % to 67.43 %, can reach the soil during the treatments, despite the fact that penconazole is applied to the foliage. The high values of the coefficient of variation for data within rows show considerable variability in all applications, ranging from 30 to 65 in the first application, from 35 to 79 in the second and from 36 to 75 in the third. Since the applications of penconazole occurred under almost same climatic conditions in terms of wind speed and direction, the high variability of concentration of penconazole found within mid-rows was attributed to the uneven slope of the vineyard causing an irregular speed of the sprayer equipment. However, least significant differences of the mean values did not end in a significant difference of penconazole concentration among mid-rows for all applications, indicating that the variability between rows does not contribute to the overall variability. The calculated half-life values for penconazole in tilled soil were 62.4 days for tilled and 33.0 for grassed soil, highlighting the tendency of penconazole to faster dissipate in grassed than in tilled soil. Grassed soil was characterised by a higher metabolic activity in terms of microbial biomass carbon content, basal respiration and total hydrolytic activity, than tilled soil. A significant correlation between penconazole dissipation and total hydrolytic activity, was found. The faster dissipation of penconazole in grassed soil was attributed to the higher amount of the total hydrolytic activity which, in grassed soil, was 1.5 fold-higher than in tilled soil.

New modeling approaches that include the use of GIS are under development in order to allow a more realistic assessment of environmental contamination by pesticides. This paper reports a regional GIS-based risk assessment using a software tool able to simulate complex and real crop rotations at the regional scale. A single pesticide leaching assessment has been done. The mean annual pesticide concentration in leachate has been analyzed using both stochastic and deterministic approaches. The outputs of these simulations were mapped over the sampling locations of the regional pesticide monitoring program, demonstrating that GIS-based risk assessment can be used to establish new monitoring programs. A multiple pesticide leaching assessment for analyzing the risk related to pest control strategies in six different maize-based rotations has been carried out. Additive toxic units approach has been used. Crop rotation allows to mediate the risk related to pesticide use because forces the use of different compounds with different fate and toxicology properties.

A field experiment is reported to ascertain the drift of two pesticides (chlorpyrifos and metalaxyl) in a vineyard in Italian climatic conditions and the effect of mitigation measures, such as buffer zones and tree rows, on pesticide drift contamination in a small aquatic system located inside the field. Results indicated that, in typical Italian agricultural conditions, spray drift in vineyards occurs at a distance of more than 24 m and adequate buffer zones are required to protect surface water bodies from direct contamination. The presence of tree rows in front of the water body inside the agricultural field, against the main wind direction, resulted in a very high reduction of the spray drift and of the ecotoxicological risk for aquatic ecosystem. In addition, a comparison between the data obtained in the experiment and the Drift Calculator procedure showed that the model failed when the procedure is used for short distances. However, concordance was found in terms of maximum drift distances.

To investigate the effects of moist olive husks (MOH-residues) on soil respiration, microbial biomass, and enzymatic (o-diphenoloxidase, beta-glucosidase, dehydrogenase and alkaline phosphatase) activities, a silty clay soil was incubated with 0 (control), 8 x 10(3) (D), 16 x 10(3) (2D) and 80 x 10(3) (10D) kg ha-1 of MOH-residues on a dry weight basis. Soil respiration and microbial biomass data indicated that the addition of MOH-residues strongly increased microbial activity proportionally to the amounts added. Data of qCO2 suggested that the respiration to biomass ratio of the microbial population was strongly modified by MOH-residues additions during the first 90 days of incubation. The qCO2 data suggested a low efficiency in energy yields from C oxidation during the first 2 months of soil incubation. qFDA seemed to be relatively unaffected for treatments D and 2D as compared to the control, but was significantly lowered by the application of 10D, showing the lowest hydrolytic activity of microbial biomass in this treatment up to 360 days of incubation. o-Diphenoloxidase activity was delayed, and this delay was extended with the addition of larger quantities of MOH-residues. Alkaline phosphatase, beta-glucosidase and dehydrogenase activities were in line with the findings on microbial biomass changes and activities. The biological and biochemical data suggest that the addition of a large quantity of MOH-residues (80 x 10(3) kg ha-1) strongly modifies the soil characteristics affecting the r- and K-strategist populations, and that these changes last for at least the 360 days of incubation. The data also suggest that application rates exceeding 16 x 10(3) kg ha-1 are not recommended until the agro-chemical and -physical functions of the soil are further studied.

To understand phosphorus (P) mobility in agricultural soils and its potential environmental risk, it is essential to directly measure solid phase P speciation. Often, bulk P K‐edge X‐ray absorption near edge structure (XANES) spectroscopy followed by linear combination fitting (LCF) is utilized to determine the solid P phases in soil. However, this method may limit results to only a few major phases. Additionally, XANES spectra for different P species may have very similar features, leading to an over‐ or underestimate of their contribution to LCF. Here, an improved P speciation by pairing multimodal microbeam‐X‐ray fluorescence (µ‐XRF) mapping coupled with µ‐XANES (microbeam‐X‐ray absorption near edge structure) analysis to directly speciate major and minor P phases on the micron scale is provided. We combined maps of both tender (P, sulfur, aluminum, and silicon) and hard energy (calcium, iron [Fe], and manganese) elements to evaluate the elemental co‐locations with P. To better account for uncertainty assigning XANES peaks to individual compounds, a more quantitative fingerprinting by "spectral feature analysis" was completed. With this analysis, an R‐factor is reported for the fit. These results were compared to traditional LCF. Pre‐edge fitting results revealed the presence of a two‐component pre‐edge feature for phosphate adsorbed to ferrihydrite. Additionally, phytate co‐precipitated with ferrihydrite (Phytate‐Fe‐Cop) had a pre‐edge feature, indicating direct association with Fe. Lastly, a unique P species associated with manganese oxide was identified in the soil via multimodal mapping and µ‐XANES. These results allow for better prediction of P dissolution and mobility. Core Ideas: Coupling multimodal microbeam‐X‐ray fluorescence maps with µ‐XANES (microbeam‐X‐ray absorption near edge structure) spectra aids in phosphorus species identification in soils.Fingerprinting by spectral feature analysis overcomes common problems of self‐absorption in LCF of P µ‐XANES.Phosphate adsorbed to ferrihydrite has a two‐component pre‐edge feature determined via spectral feature analysis.Phytate co‐precipitated with ferrihydrite has a pre‐edge feature and a peak shift to higher energy.A unique species of phosphorus associated with manganese oxide was identified via multimodal mapping and µ‐XANES. [ABSTRACT FROM AUTHOR]

Pesticides affect biota inside and outside agricultural fields due to their intrinsic mode of action. This study investigated whether pesticide active substances (AS) approved for conventional agriculture in Europe differ in their ecotoxicity from AS approved for organic agriculture. The evaluation was based on official ecotoxicological data for surrogate honeybee, bird, and earthworm species, which also serve as a reference for official environmental risk assessments in the pesticide authorization process. In October 2022, 268 chemical-synthetic AS approved for conventional and 179 nature-based AS approved for organic agriculture were listed in the EU Pesticide Database. Ecotoxicological data were only available for 254 AS approved for use in conventional agriculture and 110 AS approved for use in organic agriculture. The results showed a higher ecotoxicity of conventional AS: 79% (201 AS), 64% (163 AS) and 91% (230 AS) were moderately to acutely toxic to honeybees, birds, and earthworms, respectively, compared to 44% (48 AS), 14% (15 AS) and 36% (39 AS) of AS approved for organic agriculture. We have only considered the potential ecotoxicities of individual substances in this assessment; actual exposure in the field, where multiple AS formulations with other chemicals (including impurities) are applied, will be different. Nevertheless, these results emphasize that an increase in organic agriculture in Europe would reduce the ecotoxicological burden on biodiversity and associated ecosystem services. [ABSTRACT FROM AUTHOR]

Organic carbon performs essential functions in soils, which act as sources or sinks of atmospheric organic carbon. Agricultural management affects the carbon cycle in the soil, with effects on climate change. One of the crops most vulnerable to climate change is coffee. Brazil is the world’s largest coffee producer, with a predominance of management under a conventional system, with sloping terrain and the absence of conservationist practices. The absence of conservationist practices increases in soil loss rates due to water management and carbon emissions, as well as a reduction in coffee production. This paper intended to estimate soil and organic carbon losses by RUSLE in coffee farms in southern Minas Gerais, south-eastern Brazil. Data were obtained from fieldwork, laboratory analysis, and cartographic products. The results indicated, exclusively for coffee crops, soil and carbon losses between 7 and 32 Mg ha−1 year−1 and 87 and 460kg ha−1 year−1, respectively. However, the highest soil losses occurred on sloping terrains with eucalyptus plantations located downhill, and the lowest losses occurred on flat land with native forests. Organic carbon losses were linked directly to soil losses, as a result from the land practices, slope and agricultural management adopted. These results can be used for the planning and priority definition of areas needing conservationist practices, such as green manuring, planting in contour and maintaining of vegetation between coffee rows, which are already used in some sites of the study area. [ABSTRACT FROM AUTHOR]

Globally, food security has become a critical concern due to the rise in human population and the current climate change crisis. Usage of conventional agrochemicals to maximize crop yields has resulted in the degradation of fertile soil, environmental pollution as well as human and agroecosystem health risks. Nanotechnology in agriculture is a fast-emerging and new area of research explored to improve crop productivity and nutrient-use efficiency using nano-sized agrochemicals at lower doses than conventional agrochemicals. Nanoparticles in agriculture are applied as nanofertilizers and/or nanopesticides. Positive results have been observed in terms of plant growth when using nano-based agricultural amendments. However, their continuous application may have adverse effects on plant-associated rhizospheric and endospheric microorganisms which often play a crucial role in plant growth, nutrient uptake, and disease prevention. While research shows that the application of nanoparticles has the potential to improve plant growth and yield, their effect on the diversity and function of plant-associated microorganisms remains underexplored. This review provides an overview of plant-associated microorganisms and their functions. Additionally, it highlights the response of plant-associated microorganisms to nanoparticle application and provides insight into areas of research required to promote sustainable and precision agricultural practices that incorporate nanofertilizers and nanopesticides. [ABSTRACT FROM AUTHOR]

The reuse of wastewater to meet irrigation requirements and slurries, sludges and manures as fertilisers to meet crop nutrient demands inadvertently introduces human and veterinary-use pharmaceuticals into the agroecosystem. This review synthesises recent research, which has observed sublethal effects, following pharmaceutical uptake by plants. Potential links between pharmaceutical mode of action and observed sub-lethal effects in the plant were then examined. Common receptors and biological pathways across species suggests a clear need to integrate plant cellular biology into our understanding of the impacts of pharmaceuticals on important plant functions and processes. To help prioritise future research efforts an analysis of shared mammalian and plant biochemical pathways was undertaken to identify classes of pharmaceuticals which may present a greater risk to key plant functions. These included sulfonylurea antihyperglycemics, steroids, opiods, antipsychotic phenothiazines and pharmaceuticals targeting several neurotransmitters shared between mammals and plants (including beta-blockers, antihistamines and benzodiazepines). Whilst a number of pharmaceutical induced sub-lethal effects have been observed, this review highlights the clear need to study a wider range of pharmaceuticals on a broader range of plant species, including cover crops and wild plants, under realistic exposure scenarios, to fully understand the wider implications of pharmaceutical exposure in agro-ecosystems. State-of-the art omics-techniques offer great potential to understand the mode of action of pharmaceuticals in plants and elucidate links between the pharmaceutical intended mode of action and observed plant effects. In addition, studies under co-stress from pharmaceutical exposure and other stressors such as increased temperatures, drought or pests are lacking and present an urgent research need in the face of feeding a growing population under the threats of climate change. [ABSTRACT FROM AUTHOR]

Myclobutanil is a systemic fungicide belonging to the triazole group, which is frequently detected in environmental samples. Triticonazole, also a triazole fungicide, controls soil and seed-borne diseases and it is mainly used as a seed-coating pesticide. Both myclobutanil and triticonazole are considered as persistent pollutants in the environment, raising concerns about their environmental fate and ecotoxicity potential. The purpose of the present study was to investigate the efficiency of four pilot-scale horizontal subsurface flow (HSF) constructed wetlands (CWs) to remediate myclobutanil and triticonazole from artificially polluted water. Daily loading of the four CWs took place from March 2022 to July 2022 with contaminated water fortified with myclobutanil and triticonazole. Three of the CWs, encoded WMG-R, WMG-C, and WMG-U, with medium gravel (MG) as porous media and the fourth, with code name WFG-R, fine gravel (FG). Common reed (R, Phragmites australis) was planted in the WMG-R and WFG-R units, and cattail (C, Typha latifolia) in the WMG-C unit. The WMG-U unit with no plant was used as a control unit. The results showed that the removal rate follows the pattern: WFG-R (88.4%) > WMG-R > (83.4%) > WMG-C (59.3%) > WMG-U (36.6%) and WFG-R (88.5%) > WMG-C (71.0%) > WMG-R > (70.9%) > WMG-U (49.2%) for myclobutanil and triticonazole, respectively. The most significant factors influencing the fungicides' dissipation were the porous media content and the plant species. [ABSTRACT FROM AUTHOR]

Copper has been successfully used in the sulfate form as a fungicide to control grapevine diseases since 150 years, yet high Cu accumulation in vineyards may alter soil life. Although actual Cu additions are about tenfold lower than 50 years ago, the use of Cu in the context of the agroecological transition is still debated. Indeed, copper is one of the rare pesticides allowed for organic farming. Therefore, we performed a meta-analysis on Cu ecotoxicity by selecting 19 articles out of 300 articles relevant to copper and soil biological quality. Results show that microbial activity decreased by 30% when more than 400 kg of Cu was applied yearly per ha. Nematodes abundance remained unchanged for copper application up to 3200 kg/ha/year. Collembola and enchytraeid reproduction declined by 50% after application of 400 and 1895 kg Cu/ha/year, respectively. Earthworm biomass was reduced by 15% after application of 200 kgCu/ha/year. For soil Cu levels higher than 200 kg Cu/ha, microbial respiration decreased by 50% and no effect was observed on collembola. Overall, while toxicity is observed, the corresponding literature investigations involved Cu levels that are at least 50 times higher than the dose of 4 kg Cu/ha/year currently authorized by the European Commission for viticulture. As a consequence, applying copper at 4 kg/ha/year should not modify substantially soil biological quality and functions. [ABSTRACT FROM AUTHOR]

Imazamox is an herbicide intensively used in the peanut fields of Turkey. Carbon and nitrogen mineralizations were determined at 20 °C to evaluate the effects of the herbicide in soils humidified to 60% and 80% of field capacity (FC) over 45 days. Three doses of this herbicide [recommended dose (RD, 10 mg kg-1), 2x RD, and 4x RD] were added to soils without any previous imazamox application (NI) and to peanut soils with previous applications of imazamox (I). Carbon mineralization, determined by CO2 respiration, at RD of I soil at 80% humidity was higher than that of the other herbicide doses at both 80% and 60% humidities. NO3-N contents (mg kg-1) of I and NI soil controls were significantly higher than with all herbicide doses at 80% and 60% of FC. Nitrate production decreased with increasing doses of herbicide and was significantly lower in I soil than NI soil at both humidity levels. It may be concluded that the presence of imazamox in both soils was negatively affected by nitrate bacteria. [ABSTRACT FROM AUTHOR]

The dissipation routes of chlorpyrifos spiked in an Udic Ferrisol at the dosage of 400 ngg-1, which represents a residual level after an agricultural application, were studied in a laboratory, using the natural soil under three moisture regimes, sterilised, and organic matter-free soils in the dark at 20°C. The obtained results showed that higher soil moisture caused faster dissipation, and the abiotic and biotic contributions to the total dissipated amount of the applied chlorpyrifos in the soil accounted for 77.3-85.2% and 14.7-- 22.7%, respectively. In the sterilised soil, the contribution of organic matter to chlorpyrifos dissipation was noticed to account for 95% in the earlier two weeks, and was nearly equal to that of soil minerals two weeks after the incubation. [ABSTRACT FROM AUTHOR]

The demand for operational tools at a catchment scale is growing to assess both the sustainability of agricultural practices and the efficiency of mitigation measures on pesticide transfer to surface water. Here a literature review of 286 investigations highlights the large number of indicators and hydrochemical models developed at the catchment scale. Given this large number of indicators and models, the choice is difficult for potential users. Therefore, this article proposes a multi-criteria analysis applied to ten existing tools including physically based and conceptual models, indicators and multi-agent systems. We found the following major points: (1) Indicators and conceptual models are the most popular approaches to assess the transfer of pesticides to surface water at the catchment scale due to a trade-off between environmental relevance and adaptation to user's needs. (2) The latest indicators developed are inferred from the results of conceptual or physically based models to combine the strengths of each approach. (3) Only a handful of physically based models have addressed both flow and pesticide transport at the catchment as affected by the internal heterogeneity of the system. However, it is only physically based models that can simulate the impact of changes to the catchment. Physically based models integrate feedbacks between hydrological and chemical processes not possible from conceptual models or indicators alone. (4) The ability of models to assess the pesticide loads both in the dissolved and particulate phases is a key issue not properly addressed by many indicators or models. A key way forward is the integration of erosion processes with the fate of pesticide adsorbed to these particles. (5) At the catchment, the hydrological connectivity is perhaps the primary hydrological variable required to correctly assess rapid flow processes as surface runoff and associated pesticide transfer. This in turn implies using tools that explicitly represent the connectedness of surface and/or sub-surface water pathways including mitigation measures to correctly assess the risk of pesticide transfer. [ABSTRACT FROM AUTHOR]

This paper analyses flow and transport of pesticides from the unsaturated zone to groundwater so as to predict concentration of those contaminants in the Fucino Plain’s groundwater, by site investigations and numerical simulations. Pesticides were detected in surface water (peaks of 13 μg L−1) and groundwater (peaks of 0.37 μg L−1). Modelling tools made it possible to identify that pattern of precipitation, organic matter content, and root thickness are the key factors involved in vertical seepage of pesticides. Numerical simulations indicated that a significant fraction of contaminants is leached from the most surficial soil layers through runoff, while only a secondary fraction is mobilised towards groundwater. Likelihood of contaminating deep groundwater is fairly low, whereas surface waters show higher susceptibility. Results of the proposed conceptual hydrogeological model show that pesticides are more likely to be entrained by mixing of stream water with shallow groundwater in periods of high water exploitation from shallow wells. [ABSTRACT FROM AUTHOR]

Contamination caused by pesticides in agriculture is a source of environmental poor water quality in some of the European Union countries. Without treatment or targeted mitigation, this pollution is diffused in the environment. Pesticides and some metabolites are of increasing concern because of their potential impacts on the environment, wildlife and human health. Within the context of the European Union (EU) water framework directive context to promote low pesticide-input farming and best management practices, the EU LIFE project ArtWET assessed the efficiency of ecological bioengineering methods using different artificial wetland (AW) prototypes throughout Europe. We optimized physical and biological processes to mitigate agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems. Mitigation solutions were implemented at full-scale demonstration and experimental sites. We tested various bioremediation methods at seven experimental sites. These sites involved (1) experimental prototypes, such as vegetated ditches, a forest microcosm and 12 wetland mesocosms, and (2) demonstration prototypes: vegetated ditches, three detention ponds enhanced with technology of constructed wetlands, an outdoor bioreactor and a biomassbed. This set up provides a variety of hydrologic conditions, with some systems permanently flooded and others temporarily flooded. It also allowed to study the processes both in field and controlled conditions. In order to compare the efficiency of the wetlands, mass balances at the inlet and outlet of the artificial wetland will be used, taking into account the partition of the studied compound in water, sediments, plants, and suspended solids. The literature background necessary to harmonize the interdisciplinary work is reviewed here and the theoretical framework regarding pesticide removal mechanisms in artificial wetland is discussed. The development and the implementation of innovative approaches concerning various water quality sampling strategies for pesticide load estimates during flood, specific biological endpoints, innovative bioprocess applied to herbicide and copper mitigation to enhance the pesticide retention time within the artificial wetland, fate and transport using a 2D mixed hybrid finite element model are introduced. These future results will be useful to optimize hydraulic functioning, e.g., pesticide resident time, and biogeochemical conditions, e.g., dissipation, inside the artificial wetlands. Hydraulic retention times are generally too low to allow an optimized adsorption on sediment and organic materials accumulated in artificial wetlands. Absorption by plants is not either effective. The control of the hydraulic design and the use of adsorbing materials can be useful to increase the pesticides residence time and the contact between pesticides and biocatalyzers. Pesticide fluxes can be reduced by 50–80% when hydraulic pathways in artificial wetlands are optimized by increasing ten times the retention time, by recirculation of water, and by deceleration of the flow. Thus, using a bioremediation method should lead to an almost complete disappearance of pesticides pollution. To retain and treat the agricultural nonpoint-source po a major stake for a sustainable development. [ABSTRACT FROM AUTHOR]

Pollution swapping occurs when a mitigation option introduced to reduce one pollutant results in an increase in a different pollutant. Although the concept of pollution swapping is widely understood, it has received little attention in research and policy design. This study investigated diffuse pollution mitigation options applied in combinable crop systems. They are cover crops, residue management, no-tillage, riparian buffer zones, contour grass strips, and constructed wetlands. A wide range of water and atmospheric pollutants were considered, including nitrogen, phosphorus, carbon, and sulfur. It is clear from this investigation that there is no single mitigation option that will reduce all pollutants. [ABSTRACT FROM AUTHOR]

Development of degradation rate information for crop protection products in soil is typically a time consuming and costly process. Therefore, development of methodology that would allow extrapolation of limited degradation information to wider field conditions in a predictive fashion would be desirable. This study presents an approach that uses a modified heat unit model to estimate organic compound degradation time using limited datasets. The model requires daily soil or air temperature and volumetric water content. Predictions based on the model for three different compounds in five different field studies were within 80% of measured values based on soil analysis. Results from this research indicate that the model was able to predict compound half-life values across all sites with r² = 0.99. [ABSTRACT FROM AUTHOR]