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Weeds pose one of the major threats to plant production, as they can reduce yield, interfere with harvest, and host different harmful organisms. Unlike crops, weeds are characterized by great plasticity and adaptability to agroecosystem changes, making them an even more critical threat in a constantly changing environment. The influence of climate change in the form of different stresses to which plants are being more and more exposed is being extensively studied in crops, yet there are few studies concerning weeds. Still, considering the adaptability potential of weeds, they can represent an even more significant threat to agricultural production when abiotic stress, such as salinity, is introduced in the agroecosystem. Currently, remote sensing techniques may be exploited to derive useful, frequent, and low-cost information at different spatial scales. In this work, the Structure from motion (SfM) technique paired with Unmanned Aerial Vehicles (UAV) was used to map the distribution changes of Abutilon theophrasti in July and August 2022 in three different crop fields in the Po river delta, North-Eastern Italy. The multi-temporal orthomosaics obtained by two various SfM surveys had an image resolution of 2 cm, allowing an accurate photo interpretation and the realization of precise maps of species distribution. In the meantime, different soil samples have been taken from the fields above, and their position was measured by a Global Navigation Satellite System (GNSS), GeoMax Zenith 40. The salinity level of soil samples has been determined by measuring the electrical conductivity using XS Instruments COND 80 electrical conductivity meter (Giorgio Bormac s.r.l, Carpi, Italy) at a sensitivity of 1 µS. Salinity values were spatialized in the study areas, realizing salinity maps through the spatial interpolation tools of the Geographic information system (GIS) software. The salinity maps overlapped the maps of single plants of A. theophrasti. In both of the multi-temporal surveys performed, results show that plants of A. theophrasti can be found in areas where the soil salinity is higher than 8 dS/m, where most of the crop plants have perished. Considering that the weed plants were present at the same place in both surveys, this indicates that A. theophrasti can tolerate the rise of salinity in the fields better than the crop plants and can therefore outcompete them. These results suggest that soil salinization can have a double negative effect on crop production, both causing abiotic stress and increasing competition. Acknowledgments: This study was carried out within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR) – MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4 – D.D. 1032 17/06/2022, CN00000022).

The herbicide glyphosate (N-phosphonomethylglycine) has been the most commonly applied herbicide worldwide for the past 40 years. This review presents and discusses the state of knowledge concerning groundwater contamination by glyphosate and its metabolite, aminomethylphosphonic acid (AMPA). A dataset of 48 reports and articles reporting on glyphosate and AMPA in groundwater worldwide was constructed from the published literature. Specific attention was given to the analysis of available studies on glyphosate and AMPA transport in groundwater to investigate groundwater contamination factors. The information presented in this review highlights detectable groundwater contamination in several countries, with many cases exceeding European groundwater quality standards. Both agricultural and non-agricultural applications of glyphosate can be significant sources of pollution, and proximity to agricultural fields is a significant risk factor. AMPA has two primary sources, glyphosate and amino polyphosphates, but very little information is available about the origin of AMPA detected in groundwater. Glyphosate and AMPA transport to groundwater can be significant in well-structured soils that are rich in macropores, where it generally occurs via preferential flow. An inverse relationship was highlighted between the groundwater depth and glyphosate and the occurrence and concentration of AMPA in groundwater; however, some discrepancies among the studies were identified. Heavy rainfall shortly after glyphosate application poses a high risk of its transport to groundwater. Seasonal trends in glyphosate and AMPA in groundwater, related to application timing, agronomic practices, and weather conditions, were also observed. Finally, risk-management measures are proposed.

As the world population reaches eight billion people with indications of further growth, food security becomes one of the most important topics. At the same time, agriculture is facing a loss of arable land, reducing production capacities. Soil salinization represents a growing threat to coastal agriculture, as the combination of sea level rise and prolonged drought conditions. Identifying and mapping areas prone to this type of risk might help apply precise soil meliorative techniques and choose the right crop to grow in these soils. Nowadays, remote sensing techniques can provide valuable information for this purpose, thanks to frequent and low-cost data at different spatial scales. In this research, the Structure from motion (SfM) technique paired with Unmanned Aerial Vehicles (UAV) was used to assess the fitness of two different crops: soybean (Glycine max) and maize (Zea mays) in different salt-affected fields, in the Po river delta, North-Eastern Italy. Multi-temporal SfM surveys, using a multi-spectral camera, were conducted in July and August 2022 to map the consequences of high soil salinity (due to significant drought, low discharge, and consequent saltwater intrusion along the reaches of the Po river delta) on the vegetative status of crops through vegetation indices like the Normalized Difference Vegetation Index (NDVI). Moreover, to measure the salinity level, geolocated soil samples were taken from each field, and the amount of salt was determined using electrical conductivity using XS Instruments COND 80 electrical conductivity meter (Giorgio Bormac s.r.l, Carpi, Italy) at a sensitivity of 1 µS. Salinity values measured in the field were used to create salinity maps through spatial interpolation in GIS software. The latter allowed the salinity maps to be compared with orthomosaics of NDVI values obtained from SfM surveys. Furthermore, multi-spectral images from open-source satellites made it possible to broaden the scale of investigation in both spatial and temporal terms and to compare different data acquisition techniques. Results show a clear relationship between high-ground salinity measurements and low NDVI values, highlighting how remote sensing techniques could provide helpful information for monitoring the progressive effects of soil salinity on crops. It can be observed that soybean is quite sensitive to salinity, perishing after a long exposure even to medium-low salinity levels (1.5 dS/m – 2 dS/m). At the same time, maize seems more tolerant, with plants also surviving high salinity levels (more than 5 dS/m). Other than indicating salinity stress to which plants are exposed, these maps could also apply salt-reducing techniques, such as flushing, more precisely, thus obtaining optimal results while saving water.Acknowledgments: this study was carried out within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR) – MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4 – D.D. 1032 17/06/2022, CN00000022).

Abstract This study investigates the adsorption and dissipation of glyphosate and the formation/dissipation of AMPA in non-tilled (NT) and conventionally tilled (CT) soil at 0–5 and 5–20 cm depth. Glyphosate adsorption was mainly related to the different NT and CT soil properties (clay and amorphous Al oxides), whereas an effect of the soil management could not be identified. Glyphosate dissipation was initially fast, and it slowed down later. The initial glyphosate concentration in NT soil at 0–5 cm was significantly lower than the dose applied due to the interception by the weeds and crop residues. AMPA began to form early after treatment and persisted longer than glyphosate. The DT50 range was 8–18 days for glyphosate and 99–250 days for AMPA. Longer glyphosate and AMPA DT50 were observed in NT soil compared to CT soil but, for glyphosate, the difference was significant only at 5–20 cm. Higher glyphosate and AMPA concentrations were detected in NT than in CT soil at the end of the study at 0–5 cm. The differences in glyphosate and AMPA DT50 and persistence were mainly attributable to the influence of different NT and CT soil characteristics. However, other factors could have contributed to the different glyphosate and AMPA dynamics between the soils, like glyphosate wash-off from crop residues on NT soil with the rainfall, the delayed glyphosate return to the soil by weed root exudation or weeds decomposition, and the NT soil compaction which may have reduced the microbial degradation of glyphosate at low concentrations. Graphic abstract

Weeds can be one of the most severe threats to crop production, especially when they are widespread and highly adaptable. Part of the adaptive strategy of plants is the ability to germinate in different conditions. Germination is the first developmental phase of plant life and is fundamental for its establishment. In this work, the germination of two populations of

One of the main environmental threats to sustainability and crop productivity in the agricultural sector is soil erosion. For the mitigation of this problem in agricultural fields, no-till management is considered a key approach. The measurement of soil erosion is particularly challenging, especially when surficial morphological changes are relatively small. Conventional experiments are commonly time-consuming and labour-intensive in terms of both field surveys and laboratory methods. However, the Structure from Motion (SfM) photogrammetry technique has enhanced the experimental activities by enabling the temporal evolution of soil erosion to be assessed through detailed micro-topography. This work presents a multitemporal quantification of soil erosion, using SfM through Uncrewed Aerial Vehicles (UAV) survey for understanding the evolution of no-till (NT) and conventional tillage (CT) in experimental plots. Considering that plot-scale soil surface (mm grid size) by several orders of magnitude, it was necessary to minimise SfM errors (e.g., co-registration and interpolation) in volumetric estimates to reduce noise as much as possible. Therefore, a methodological workflow was developed to analyse and identify the effectiveness of multi-temporal SfM-derived products, e.g. the conventional Difference of Digital Terrain Models (DoDs) and the less used Differences of Meshes (DoMs), for soil volume computations. To recognise the most suitable estimation method, the research validated the erosion volumetric changes calculated from the SfM outputs with the amount of soil directly collected through conventional runoff and sediment measurements in the field. This study presents a novel approach for using DoMs instead of DoDs to accurately describe the micro-topography changes and sediment dynamics. Another key and innovative aspect of this research, often overlooked in soil erosion studies, was to identify the contributing sediment surface, by delineating the channels potentially routing runoff directly to water collectors. The sediment paths and connected areas inside the plots were identified using a multi-temporal analysis of the sediment connectivity index for achieving the volumetric estimates. The DoM volume estimates showed better results with respect to DoDs and a mild overestimation compared to in-situ measurements. This difference was attributable to other factors (e.g., the soil compaction processes) or variables rather than to photogrammetric or geometric ones. The developed workflow enabled a very detailed quantification of soil erosion dynamics for assessing the mitigation effects of no-till management that can also be extended in the future to different scales with low-costs, based on SfM and UAV technologies.

Weeds are one of the major issues in agricultural production and they are present in most agricultural systems. Due to the heterogeneity of weed distribution, understanding spatial patterns is paramount for precision farming and improving sustainability in crop management. Nevertheless, limited information is currently available about the differences between conventional agricultural (CV) weed spatial patterns and weed spatial patterns in conservation agricultural systems (CA); moreover, opportunities to use unmanned aerial vehicles (UAV) and recognition algorithms to monitor these differences are still being explored and tested. In this work, the opportunity to use UAVs to detect changes in spatial distribution over time between CA and CV fields was assessed for data acquisition. Acquired data were processed using maximum likelihood classification to discriminate between weeds and surrounding elements; then, a similarity assessment was performed using the ‘equal to’ function of the raster calculator. The results show important differences in spatial distribution over time between CA and CV fields. In the CA field 56.18% of the area was infested in both years when the field margin effect was included, and 22.53% when this effect was excluded; on the other hand, in the CV field only 11.50% of the area was infested in both years. The results illustrate that there are important differences in the spatial distribution of weeds between CA and CV fields; such differences can be easily detected using UAVs and identification algorithms combined.

Weed management is a crucial issue in agriculture, resulting in environmental in-field and off-field impacts. Within Agriculture 4.0, adoption of UASs combined with spatially explicit approaches may drastically reduce doses of herbicides, increasing sustainability in weed management. However, Agriculture 4.0 technologies are barely adopted in small-medium size farms. Recently, small and low-cost UASs, together with open-source software packages, may represent a low-cost spatially explicit system to map weed distribution in crop fields. The general aim is to map weed distribution by a low-cost UASs and a replicable workflow, completely based on open GIS software and algorithms: OpenDroneMap, QGIS, SAGA and OpenCV classification algorithms. Specific objectives are: (i) testing a low-cost UAS for weed mapping; (ii) assessing open-source packages for semi-automatic weed classification; (iii) performing a sustainable management scenario by prescription maps. Results showed high performances along the whole process: in orthomosaic generation at very high spatial resolution (0.01 m/pixel), in testing weed detection (Matthews Correlation Coefficient: 0.67–0.74), and in the production of prescription maps, reducing herbicide treatment to only 3.47% of the entire field. This study reveals the feasibility of low-cost UASs combined with open-source software, enabling a spatially explicit approach for weed management in small-medium size farmlands.

Highlights - Efficacy of UAVs and emergence predictive models for weed control has been confirmed. - Combination of time-specific and site-specific weed control provides optimal results. - Use of timely prescription maps can substantially reduce herbicide use. Remote sensing using unmanned aerial vehicles (UAVs) for weed detection is a valuable asset in agriculture and is vastly used for site-specific weed control. Alongside site-specific methods, time-specific weed control is another critical aspect of precision weed control where, by using different models, it is possible to determine the time of weed species emergence. In this study, site-specific and time-specific weed control methods were combined to explore their collective benefits for precision weed control. Using the AlertInf model, which is a weed emergence prediction model, the cumulative emergence of Sorghum halepense was calculated, following the selection of the best date for UAV survey when the emergence was predicted to be at 96%. The survey was executed using a UAV with visible range sensors, resulting in an orthophoto with a resolution of 3 cm, allowing for good weed detection. The orthophoto was post-processed using two separate methods: an artificial neural network (ANN) and the visible atmospherically resistant index (VARI) to discriminate between the weeds, the crop and the soil. Finally, a model was applied for the creation of prescription maps with different cell sizes (0.25 m2, 2 m2, and 3 m2) and with three different decision-making thresholds based on pixels identified as weeds (>1%, >5%, and >10%). Additionally, the potential savings in herbicide use were assessed using two herbicides (Equip and Titus Mais Extra) as examples. The results show that both classification methods have a high overall accuracy of 98.6% for ANN and 98.1% for VARI, with the ANN having much better results concerning user/producer accuracy and Cohen's Kappa value (k=83.7 ANN and k=72 VARI). The reduction percentage of the area to be sprayed ranged from 65.29% to 93.35% using VARI and from 42.43% to 87.82% using ANN. The potential reduction in herbicide use was found to be dependent on the area. For the Equip herbicide, this reduction ranged from 1.32 L/ha to 0.28 L/ha for the ANN; with VARI the reduction in the amounts used ranged from 0.80 L/ha to 0.15 L/ha. Meanwhile, for Titus Mais Extra herbicide, the reduction ranged from 46.06 g/ha to 8.19 g/ha in amounts used with the ANN; with VARI the reduction in amounts used ranged from 27.77 g/ha to 5.32 g/ha. These preliminary results indicate that combining site-specific and time-specific weed control, has the potential to obtain a significant reduction in herbicide use with direct benefits for the environment and on-farm variable costs. Further field studies are needed for the validation of these results.

The efficacy of weed management depends on the correct control timing according to the seedling emergence dynamics. Since soil temperature and soil moisture are two main factors that determine weed germination, the hydrothermal time model can be used to predict their emergence. The aim of this study was to estimate the base temperature (Tb) and base water potential (Ψb) for germination of Chenopodium album, Amaranthus retroflexus, Setaria pumila and Panicum capillare collected from fields in continental Croatia and then to compare these values with those of Italian populations embedded in the AlertInf model. Germination tests were performed at seven constant temperatures (ranging from 4 to 27°C) and eight water potentials (0.00 to - 1.00 MPa). Estimated Tb and Ψb were 3.4°C, -1.38 MPa for C. album, 13.9°C, -0.36 MPa for A. retroflexus, 6.6°C, -0.71 MPa for S. pumila and 11.0°C, -0.87 MPa for P. capillare, respectively. According to the criterion of overlap of the 95% confidence intervals, only Tb of C. album, and Ψb of A. retroflexus were similar between Croatian and Italian populations. Further field experiments should be conducted in the Croatian field to monitor weed emergence patterns of C. album and to calibrate the AlerInf equation parameters.

Weed behaviour in crop fields has been extensively studied, nevertheless, limited knowledge is available for particular cropping systems, such as no-till systems. Improving weed management under no-till conditions requires an understanding of the interaction between crop residues and the seedling emergence process. This study aimed to evaluate the influence of maize and wheat residues, applied in three different quantities (1, the field quantity, 0.5, and 1.5-fold amounts of the field quantity), on the emergence of eight weed species: Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Digitaria sanguinalis, Echinochloa crus-galli, Setaria pumila, Sonchus oleraceus, and Sorghum halepense. The experiment was conducted over two consecutive years. The results showed that the quantities 1 and 1.5 could suppress seedling emergence by 20 and 44%, respectively, while the quantity 0.5 seems to promote emergence by 22% compared with the control without residues. Weed species showed different responses to crop residues, from C. album showing 56% less emergence to S. halepense showing a 44% higher emergence than the control without residues. Different meteorological conditions in the two-year experiment also exhibited a significant influence on weed species emergence.

Echinochloa crus-galli (L.) P. Beauv. is the most common monocotyledonous weed in maize crops in Croatia. Crop–weed interference is influenced by weed emergence patterns, and knowledge of the timing of weed emergence is crucial for the development of an efficient integrated weed-management program. Therefore, two-year field experiments were conducted in a maize crop sown in early May in continental Croatia to determine the emergence pattern of E. crus-galli from natural seedbank. In laboratory studies, the estimated base temperature and base water potential for the Croatian ecotype of E. crus-galli were 10.8 °C and −0.97 MPa, respectively. Then, the estimated germination parameters were compared with the values embedded in the AlertInf model from Italy (Veneto) to calibrate this hydrothermal model. The estimated hydrothermal units were around 28 for the onset (10%) and 93 for the middle (50%) emergence of E. crus-galli. Our findings showed that the AlertInf model satisfactorily simulated the emergence of E. crus-galli in maize crop in Croatia (EF = 0.97 in 2019 and 0.98 in 2020), indicating its potential use in other geographical areas

Conservation agriculture, and in particular no-till systems, generally yield improvements in both soil characteristics (e.g. structure, and water holding capacity) and soil processes (such as runoff and hence erosion). Nevertheless, during the first years of no-till, the soil is prone to compaction due to the poor structure, missing ploughing activities, and passage of tractors and machinery, thus favouring surface runoff and soil erosion. Little information exists about the effect of no-till when applied during the transition period from conventional to conservation agriculture. This study aimed at analysing runoff and soil erosion in a non-tilled field in comparison with a tilled field during the transition period. The study was conducted at the Padova University Experimental Farm, in northeast Italy. Six sub-plots (2.5 m × 5 m) were established, three in a tilled field (CT plot) and three in a non-tilled field (NT plot). Each sub-plot was equipped with a runoff water collection system. Runoff was monitored during two sampling seasons: from May to October 2017 and May to September 2018. Runoff water volume was measured at each rainfall event, and the amount of sediment was quantified by drying the runoff samples. This technique is simple and inexpensive and suitable to be applied also in rural areas with inadequate infrastructures and economic resources. Two indices, runoff reduction benefits (RRB) and sediment reduction benefits (SRB), were computed. During the monitoring period, 24 runoff events occurred. NT practices coincided with reductions of over 50% in runoff volumes and 50% to 95% in sediment losses. Only the runoff event just after the CT soil harrowing produced a significantly lower runoff and sediment loss in CT than in NT field, due to the effect of soil tillage on surface roughness and rainfall infiltration. The average sediment concentration in NT was only 47% of CT. The RRB and SRB values confirmed a reduction in runoff and sediment loss in the NT compared with the CT plot, but SRB was greater than the RRB, indicating that the no-till regime showed a better control of sediment loss than it did the runoff amount. The reduced runoff and sediment yield in the NT plot could have important on-site benefits in terms of both sustainable soil management and surface water quality.

Glyphosate is the most used herbicide worldwide, especially in conservation agriculture, where the lack of mechanical weed control often necessitates chemical inputs. In conservation agriculture, the elimination of tillage operations leads to changes in soil physical, chemical, and biological properties. Consequently, herbicide environmental fate may be potentially altered relatively to conventional tillage systems. The aim of this study was, therefore, to investigate the effect of conservation agriculture and conventional tillage on the adsorption of glyphosate and on the dissipation of glyphosate and its primary metabolite aminomethylphosphonic acid (AMPA) at two depths, 0−5 and 5−20 cm.The field trial was conducted from October 2018 to April 2019 at the Padua University Experimental Farm, North-East Italy. Glyphosate was applied as a formulated product (Roundup Power 2.0) at a dose of 1.44 kg/ha of the active ingredient. The dissipation of glyphosate and the formation/dissipation of AMPA were followed for 182 days after their application. The concentrations of glyphosate and AMPA in the soil were analysed by Ultra-High Performance Liquid Chromatography coupled with mass spectrometry. The dissipation of glyphosate was described by the first-order multicompartment model (FOMC), whereas the model for AMPA was composed of an FOMC degradation model for glyphosate and the single first-order degradation model for AMPA. The estimated trend of concentrations over time for both glyphosate and AMPA were used to derive their DT50 (time required for 50% dissipation of the initial concentration).The results indicate an increase in glyphosate adsorption in non-tilled soil compared to the tilled soil, at both depths. Glyphosate initial dissipation was fast, followed by a slower decline. At 0–5 cm no significant difference was observed in glyphosate persistence between the two soil managements, whereas at 5–20 cm glyphosate was more persistent in non-tilled soil (DT50 18 days) than in tilled soil (DT50 8 days). The fast initial dissipation of glyphosate was reflected in an increase in the concentration of AMPA. AMPA persisted longer than glyphosate but, for this metabolite, no apparent effect was observed in response to the different soil management. The higher persistence of glyphosate under conservation tillage might increase the risk of on-site soil pollution due to the accumulation of this chemical, especially in the case of repeated applications of glyphosate. Nevertheless, high glyphosate adsorption observed in non-tilled soil may reduce the leaching potential to lower soil depths.This abstract falls in the group “Soil contamination” and the subgroup “Experimental assessment”.

Weeds are one of the major problems in agriculture, they can reduce yield, interfere with harvest and serve as hosts to possibly harmful organisms. For a successful agricultural production, weed issue must be tackled in the begging, during the germination-emergence phase. With different management systems weed seed bank is exposed to different field conditions which may favour or obstruct the germination. One of these conditions is the presence or the absence of crop residues on the soil surface, very common in the newer agricultural practices, such as Conservation Agriculture. In this work the germination of eight weed species: Abuthilon theophrasti, Setaria glauca, Digitaria sanguinalis, Sorghum halepense, Amaranthus retroflexus, Sonchus oleraceus, Chenopodium album and Echinochloa crus-galli, was examined under the residues of two crop species maize (Zea mays) and wheat (Triticum sp.). For each weed species 200 seeds were used, while three different quantities of residues were used for the two crops, the quantity measured in one square meter of the field (1), half of that quantity (0,5) and a half more than the one measured in the field (1,5), plus control, without residues. The experiment was conducted at the experimental farm of the University of Padova in Legnaro (PD) in a 8x2x3 factorial design with three blocks, plus three control repetitions. Seeds of each weed species were sown in an area of 20 cm2. Before the beginning of the experiment, the soil from the designated areas was removed and sterilized at 105°C in order to prevent contamination by the seeds already present in the soil. Once the soil was sterilized and restored to the field, the seeds were sown on the surface of the soil and covered with the respective quantity of the respective crop residue or left uncovered in the case of control. The experiment started on December 2018, and the seeds were left undisturbed during the winter, imitating natural conditions. Seeds started germinating on March 2019 and were controlled twice a week until the end of germination process, all germinated plants were removed and counted. ANOVA and LSD analysis were performed on cumulated germination data. Only quantity of residues and weed species resulted significant as factors (p-value < 0,000). The results showed that the quantity 1 and 1,5 can reduce the germination from 10 to 30% respectively, while quantity 0,5 can in fact increase germination by 15%. As for the weed species, they were all more inhibited by the higher concentrations of residues, but in respect to control it was observed that some of them seemed to be favoured by the low presence of residues S. halepense and A. theophrasti, not particularly influenced were A. retroflexus, E. crus-galli and S. oleraceus, while C. album, D. sanguinalis and S. glauca showed major germination rate reduction. In conclusion, to obtain the weed inhibitory effect, it seems very important to pay particular attention to the homogeneity of the distribution of the crop residues on the soil surface, low residue density areas could favour weeds.

Field management practices can alter the physical and chemical properties of the soil, also causing changes to the seed bank. Alterations can also occur to the soil microbial community, which in turn can increase or diminish the process of weed seed decay. In this research, the issue of seed degradation was studied in an undisturbed and a no-till soil, trying not only to uncover where seeds are more degraded, but also to investigate the microbial activities that could be involved in this process. Six different weed species, commonly found in northern Italy, were used: Abutilon theopharsti, Alopecurus myosuroides, Amaranthus retroflexus, Digitaria sanguinalis, Portulaca oleracea and Sorghum halepense. Seed decay was tested in two different sites, a no-till field and the adjacent buffer zone. Soil microbial activity was also measured using the Fertimetro, an approach based on the degradation of cotton and silk threads buried in the soil for one week. Degradation of the buried seeds was higher in the no-till field soil than in the buffer strip for all the studied species as was the microbial cellulolytic activity. Even though the buffer strip soil is an undisturbed habitat and resulted as having higher organic matter, the no-till soil conditions appeared more unfavourable to seed viability. Our findings suggest that no-till management can improve weed seed suppression in the soil. Moreover, cellulolytic microorganisms play an important role in seedbank longevity, so cellulolytic activity surveys could be used as an early monitoring bioindicator for weed seed suppression in soil.

Summary Modelling weed seedling emergence pattern appears to be a promising approach in the development of effective weed management programmes based on the selection of optimal timing of control operations. Thermal and hydrothermal time models propose that seed germination rates are proportional to the amount by which temperature and water potential exceed threshold values for these environmental factors. Hence, base temperature for seed germination is a fundamental biological parameter for the prediction of weed emergence. A series of laboratory experiments were conducted to estimate base temperature in three weed species belonging to the Asteraceae family, predominant in conservation tillage fields in north-eastern Italy. The traditional method based on germination assays at constant temperatures was compared with a method based on assays at alternating temperatures. The latter might represent an alternative to the former for those species which do not germinate or only poorly under constant temperatures. Base temperature was estimated by regressing the reciprocal of the median germination time on temperature comparing two functions, a broken-stick and an exponential-type model. Both models showed good fit to all data in the whole temperature range and in almost all cases provided similar estimates of base temperature. The main result is that, for the weed species examined in this study, the use of alternating temperatures for base temperature estimation appears to be possible. However, further research is required to test if the use of germination assays performed at alternating temperatures can be a suitable method to estimate base temperature of species that have too low germination at constant temperatures.

The aim of the research was to determinate the degree of variation in morphological (seed weight) and functional polymorphism (final germination, dormancy, seed mortality and germination dynamic) within two seed populations of Ambrosia artemisiifolia L. Seeds were collected separately from 20 plants/population in Jastebarsko (45°40'18˝N; 15°39'03˝E), population-J and Popovača (45°34´1˝N; 16°40´43˝E), population-P in 2014. Seed weight of J and P populations had weak variability (CV-J = 18.2%, CV-P= 29.8%) with an average of 4.05 g (J) and 4.54 g (P). Estimated variability was strong for amount of death seeds in the J (CV = 67.6%), but weak for geminated (CV = 4.9%) and moderate for dormant seeds (CV = 51.0%). Variability within P population was moderate for both germinated and dead seeds (CV = 34.5%; 34.1%), while variability within amount of dormant seeds was weak (CV = 14.2%). Variability in medium germination (T50) was relatively low for both experimental populations (CV – J = 12.0%; CV – P = 22.4%). Despite determined intrapopulation variation, degrees of variability between researched parameters (final germination, dormancy and medium germination – T50) were weak or moderate and therefore acceptable for further experiment base on seed testing., Cilj istraživanja bio je utvrditi stupanj morfološke (masa sjemena) i funkcionalne (klijavost, dormantnost, smrtnost sjemena i dinamika klijanja) varijabilnosti unutar dvije populacije sjemena korovne vrste Ambrosia artemisiifolia L. (ambrozija) sakupljene u sjeverozapadnom dijelu Hrvatske: Jastrebarsko (45 ° 40'18˝N; 15 ° 39'03˝E), populacija-J i Popovača (45 ° 34´1˝N; 16 ° 40´43˝E), populacija-P. Prikupljeno je sjeme s 20 biljaka/populaciji u listopadu 2014. Rezultati istraživanja ukazuju na slabu varijabilnost (CV-J = 18,2%, CV-P = 29,8%) mase 1 000 sjemenki s prosječnom masom od 4,05 g (J) i 4,54 g (P). Intrapopulacijska varijabilnost bila je relativno visoka za udio mrtvog sjemena u populaciji-J (CV = 67,6%), ali vrlo slaba za udio klijavog (CV = 4,9%) te umjerena za udio dormantnog sjemena (CV = 51,0%). Varijabilnost unutar populacije-P bila je umjerena za udio klijavog i mrtvog sjemena (CV = 34,5%; 34,1%), a relativno slaba za udio dormantnog sjemena (CV = 14,2%). Dinamika klijanja (T10, T50 i T90) obje populacije bila je slabo ili umjereno varijabilna. Sredina klijanja (T50) bila je relativno slabo varijabilna za obje istraživane populacije (CV - J = 12,0%; CV - P = 22,4%).

Abutilon theophrasti is a weed that is spreading worldwide and that has had to adapt to different combinations of environmental conditions. Wide interpopulation variability has been reported regarding dormancy and germination. This variability, controlled by the interaction of genetic diversity and maternal effect, could hinder the adoption of Integrated Weed Management (IWM) tools. A collaborative project was conducted to compare emergence dynamics of 12 European and North American populations under diverse environmental conditions. The main aim was to assess interpopulation variability and explain this according to environmental conditions in the seed collection sites. Seeds were sown at six experimental sites, and seedling emergence was monitored. The AlertInf model was tested to evaluate its ability to predict emergence dynamics of the different populations. A wide interpopulation variability was observed for emergence percentage and dynamics with consistent trends across sites and related to different seed dormancy levels. Populations from Catalonia, Iowa and Minnesota reached higher emergence percentage with earlier and concentrated emergence flushes probably due to low dormancy level, while populations from Croatia, Serbia and Hungary, given their low average emergence percentage, presented high dormancy levels. Good predictive accuracy of AlertInf model was obtained at the different sites, confirming the possibility of adopting it across a wide range of environmental conditions. Achieving a better knowledge of interpopulation variability can allow specific control strategies to be designed, facilitating the replacement of solely herbicide- based management with true IWM.

Weeds account for losses in crop yields, and this event might be exacerbated by salinity. Therefore, we investigated the responses of Chenopodium album L. and soybean (Glycine max (L.) Merr.) to salt stress, as well as interferences between species. Ten-day old plants were grown for 1 week in a single- or mixed-species set-up, either with or without 100 mM of NaCl. C. album reduced the biomass of soybean similarly to salt stress, while its growth was unaffected under any condition. C. album decreased the crop protein content when salinity was applied. This effect was ascribed to altered protein metabolism and/or N usage to produce other N metabolites, including osmolytes. The two species did not reciprocally affect the capacity to accumulate Na+, but the weed contained two-fold more Na+ in the leaves. Elevated initial K+ concentration and high K+ delivery to the shoot likely explained the better acclimation of C. album to salinity. C. album produced more phenolics and proline and exhibited greater antioxidant activity, but low lipid peroxidation, in the mixed set-up under salinity. Thus, it is possible that the weed could become more resilient to salinity when growing in a soybean field. In the long term, this might cause significant losses in soybean productivity as expected by the dramatic decline in crop protein content.

Among the most invasive species, the Coypu (Myocastor coypus) best exemplifies the widespread effect of alien species to ecosystems. Among the impacts, the induced erosion in riverbanks has an increasing economic and social importance. Despite its significance, this type of erosion is rarely quantified, and the available information is limited to local knowledge, grey literature, and maintenance reports. This research shows the potential of freely and instantly available structure-from-motion (SfM) photogrammetry to obtain crowdsourced information based on smartphone images. The results highlight how it is possible to provide a rough estimate of the damages with a relative low or null cost of application, and a limited expert knowledge and expenditure of time, depending on the scale of analysis. The proposed technique provides a fresh approach to a known long-standing issue, offering a new source of information for farmers, researchers, wildlife managers, as well as for land managers and planners. The potential applications of such technique and its unprecedented ease of use and very low cost offer effective tools for management plans and scientific research, providing a basis to relate eroded volumes to the functioning of the drainage system and the connected agroecosystem. The method would also enable the opportunity of participatory and opportunistic crowd-sourced sensing. Further scientific research on the crowd-based data on erosion should encourage standardisation of data gathering and accessibility, together with a public involvement in information exchange, to generate a better understanding and awareness of erosion problems also for other fields of research. This article is protected by copyright. All rights reserved.

The aquifer north of Vicenza, Italy, is one of the main and most studied drinking water reservoirs within the Veneto region. The area is an intensive cropland, and monitoring of s-triazine herbicides and metabolites has been carried out since the late eighties. This study analysed the trends of atrazine (ATR), terbuthylazine (TBZ), deethyl-atrazine (DEA), and deethyl-terbuthylazine (DET) concentrations from 1987 to 2016 and related the variations of agricultural land use, herbicide load, and pesticide regulations to the residence time of pollutants in the aquifer. In total, 785 water samples collected from 82 selected check wells were analysed with high-resolution gas chromatography combined with mass spectrometry. Non-detects were substituted by one-half the limit of detection. Over the 30 years of monitoring, concentrations of all of the pollutants decreased at all sampling sites. Since the beginning, TBZ and DET residues have been systematically lower than ATR and DEA, respectively, with more than 70% of the data below the limit of detection and never exceeding the European Maximum Acceptable Concentration (MAC) for a single pesticide (0.1 μg/L). The highest concentrations of ATR and DEA showed a spatial shift along the flow direction, suggesting an increase in groundwater residence time from the recharge zone to the accumulation zone of the aquifer. The last residues of ATR were found 27 years after its ban. Although all of the concentrations were lower than those found elsewhere in Europe, the sum of s-triazines overcame the MAC in 20% of the samples. Considering the structural and toxicological similarities of s-triazines, these findings confirm the necessity of better characterisation of the toxicological risk posed by mixtures.

The spread diffusion of wildlife in agroecosystems has induced conflictual interactions with humans, representing a critical issue, especially in terms of damages made on crops. They include deterioration of green and woody parts of crops, removal of seeds, crushing of cultivations, soil degradation. In this regard, a multi-temporal geolocalization and quantification of wildlife impact in agricultural landscapes is still a challenging point to be explored. The purpose of this research is to present a methodological approach, with the involvement of citizens (farmers and fields' owners) in the data collection, to analyze wildlife damages. The study area is the Treviso province, located in North East of Italy. A multi-temporal analysis is carried out considering the period 2009 up to 2018. In detail, a multi-temporal thematic mapping was realized classifying data in terms of wildlife species, damaged crops, and surface covered by affected cultivations. Such data were then processed through multi-variate statistical analysis. The results provide a clear overview of the phenomena in the investigated region, highlighting the fact that the uncontrolled spread of wildlife is responsible for severe damages on agroecosystems. In this connection, damages made by winged species and wild boar are the most numerous, respectively, with 1007 and 497 damages within the considered period. Corn is the most damaged crop, with a total of 977 damages observed on it between 2009 and 2018. Cross tabulation and cluster analysis have confirmed the magnitude of the problem taken into account. Such information could be used then by the local administrations to better understand the phenomena, providing suitable measures to contain it.

This study evaluates the effect of sewage amendment (SA) on the dissipation of terbuthylazine, its degradation compound desethyl-terbuthylazine, and S-metolachlor in the soil. The experiment was conducted at Padua Experimental Farm (Italy). Herbicides dissipation was evaluated in soils differently fertilized for three years: with inorganic fertilizer, with sewage sludge, and with a combination of them. Terbuthylazine and S-metolachlor were applied on sorghum as a formulated product at a dose of 2.8 L ha

Glyphosate is the most used pesticide worldwide and its impact on the environment is becoming increasingly significant. Glyphosate and its main metabolite AMPA are frequently detected in streams and rivers. In this study, an analytical method is presented that combines Ultra-High Performance Liquid Chromatography with mass spectrometry (UHPLC–ESI-MS/MS) for glyphosate and AMPA analysis in environmental water samples. The method was developed starting from an application of Waters Corporation, and involves the use of an alternative derivatizing reagent, the commercially available AccQ·Tag™ Ultra Derivatization Kit (Waters Corporation, Milford, MA, USA). The kit contains the derivatizing reagent 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Derivatization takes place directly in the injection vial and no sample pre-concentration is needed. The derivatization is simple, quick and robust, which fits well within the needs of a routine method for the analysis of glyphosate and AMPA. Derivatized glyphosate and AMPA were recorded in positive ion mode. The method demonstrates a good linear relationship in the concentration range from 0.2 μg/L for glyphosate and 0.05 μg/L for AMPA to 100 μg/L and an accurate recovery. The method developed has been successfully applied to the determination of glyphosate and AMPA in 23 runoff water samples collected from a field in the Po Valley (North-East Italy), an agricultural area where glyphosate is widely used.

Glyphosate is the most common herbicide worldwide, and its impact on the environment has increasingly been scrutinized. Glyphosate-based formulations can contain co-formulants, among which are surfactants. This study aimed to investigate whether the presence of an alkyl polyglucoside-based surfactant, Triton CG-110, affects the adsorption, leaching, and mineralisation of glyphosate in the soil. The experiments were conducted in two soils with different textures (sandy and clay) and in washed sand. Glyphosate and surfactant mixtures were applied at realistic field rates. Because of ponding and scarce leaching from the field soil, the leaching experiments were conducted only with washed sand. The results indicate a reduction of glyphosate adsorption in washed sand (from Kf = 13.5 to 3.99 μg1−1/n (ml)1/n g−1) and in sandy soil (from Kf = 165 to 90.8 μg1−1/ n (ml)1/n g−1) when using a Triton CG-110 concentration of 0.5 %, which corresponds to that of a spraying solution applied in the field, whereas adsorption in clay soil was unaffected. Triton CG-110 did not significantly affect glyphosate leaching in washed sand or mineralisation in any of the tested soils. The results indicate that Triton CG-110 is unlikely to significantly affect the environmental fate of glyphosate in the soil at environmentally relevant concentrations.