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Aerobiology in alpine environments: exploring pollen biodiversity and its impacts on human health
Get PDFThis review summarizes methods and relevant outcomes of aerobiological studies carried out in the alpine biome worldwide impacting the knowledge on the occurrence of airborne pollen and their origin, for biodiversity studies, models of transport, forecasts, and climate change scenarios, for the reconstruction of past vegetation, and the potential impacts on human health. Deposition sampling is the method of choice, while volumetric sampling is mostly performed in densely populated mountain ranges. Conventional microscopic identification of pollen of alpine environments is rarely complemented or replaced by molecular methods. The pollen bioaerosol mirrors the surrounding vegetation but includes components from medium and distant source locations. However, there is no uniform understanding on the definition of source-scales – crucial for the interpretation of the bioaerosol constituents – to which we propose an answer. Alpine habitats, with their cold-adapted plant communities, may react to increasing temperatures with shifts in their range. The potential of using pollen as a proxy to monitor such changes in alpine biomes has been exploited in paleoecology but rarely in aerobiology. Health impacts are linked to the low allergen load in the bioaerosol and the overall effect of the alpine climate in a highly natural environment. Generally, the soothing effect is reported for respiratory allergy patients, which may be jeopardized by seasonality and allergens transported from outside. The complex topography of mountain ranges does not allow for general assumptions on the quality and quantity of bioaerosol in alpine environments. We emphasize the importance of monitoring the bioaerosol in alpine environments to evaluate the effects of global change, and to optimize the management of respiratory health issue
Comparative rainfastness assessment of different copper-based fungicides
No full textCopper antimicrobial properties have been well known since the times of ancient Egyptians, who used it to sterilize water and wounds. In the modern era, after the fungicidal properties of the Bordeaux mixture were discovered by Millardet in 1885, several fungicides were developed using different copper compounds as active substances. The long-term success of these products is linked to their high efficacy at affordable costs and the low risk of developing resistance in the target plant pathogens. However, they can be used only as contact fungicides, and most of the active substances can be washed out from the crop canopy by rainfall. Modern agrochemistry allowed the development of new formulations with increasing rainfastness. Therefore, the old assumption that copper fungicides are not helpful in the context of frequent and heavy rainfalls is no longer valid. This study assessed the rainfastness of seven products containing different copper compounds and formulation technologies after applying a simulated rain of 80 mm on grapevine potted plants. Fungicides implementing the newest formulation technology indicated an increase of metallic copper available on the leaf surface of 18.3-76.7% to the standard Bordeaux mixture and 77.5-158.5% to copper sulphate pentahydrated. Parallel efficacy trials done on Plasmopara viticola using the same products revealed a higher efficacy than the reference in heavy rainfalls, consuming less metallic copper per hectare. These results demonstrated that new copper-based fungicides withstand the challenges of extreme weather events and are essential tools for organic farming and IPM strategies
Exploring the detection of bark beetle attacks in Norway spruce forests in sentinel-1 image time series
No full textIn this study, we explored the use of long time series of Sentinel-1 SAR images for the detection of bark beetle outbreaks in temperate forests. Bark beetle attacks induce a gradual deterioration in the health of trees, ultimately leading to their death. Accordingly, time series of remote sensing data are crucial to detecting them. In this study, time series of Sentinel-1 data were collected in reference areas attacked by bark beetle in the period 2019-2022 and then the backscatter values were extracted and analyzed. A method for the automatic detection of bark beetle attacks has been developed and tested on the same polygons. The preliminary results showed that the distribution of the Sentinel-1 backscatter values in VV and VH polarizations inside the attacked polygons before and after that attack is significantly different. The detection method achieved a detection accuracy above 65% for all the dates considere
The application of direct-injection mass spectrometry techniques in studying microbial VOCs in food: flavour attributes, fermentation monitoring and emerging trends
No full textUsing process-based coupled ecological-hydrodynamic models to support regional lake water quality protection planning in Northern Italy
Get PDFSuppressive activity of Glechoma hederacea extracts against the phytopathogenic Oomycete Plasmopara viticola, and first screening of the active metabolites
Get PDFPlasmopara viticola is a destructive oomycete that affects grapevines, causing significant economic losses worldwide. This study highlights how the plant Glechoma hederacea might be at the basis for the development of biofungicides to control P. viticola. The aqueous extract obtained from G. hederacea aerial parts showed strong inhibition activity against P. viticola, comparable to that of copper hydroxide. The bioguided purification of the extract by chromatographic techniques led to the isolation of six pure metabolites, identified as the aromatic compounds carvacrol, caffeic acid and methyl caffeate, the flavonoids cirsimaritin and apigenin and the polyphenolic acid rosmarinic acid by spectroscopic methods. This is the first report about the isolation of methyl caffeate and cirsimaritin from G. hederacea. Caffeic acid and methyl caffeate showed the highest disease severity reduction, while carvacrol, cirsimaritin and apigenin also showed moderate activity against P. viticola. The inhibitory activity of the aqueous extract could suggest synergetic or additive action of caffeic acid and methyl caffeate together with other compounds contained in the extract. This study provides insights into the potential of G. hederacea as an allelopathic tool for developing control methods against P. viticola, revealing the combined action of different metabolites involved in the mechanism of action of the active compound
Impact of landscape composition on honey bee pollen contamination by pesticides: a multi-residue analysis
Get PDFThe honey bee is the most common and important managed pollinator of crops. In recent years, honey bee colonies faced high mortality for multiple causes, including land-use change and the use of plant protection products (hereafter pesticides). This work aimed to explore how contamination by pesticides of pollen collected by honey bees was modulated by landscape composition and seasonality. We placed two honey bee colonies in 13 locations in Northern Italy in contrasting landscapes, from which we collected pollen samples monthly during the whole flowering season in 2019 and 2020. We searched for almost 400 compounds, including fungicides, herbicides, insecticides, and acaricides. We then calculated for each pollen sample the Pollen Hazard Quotient (PHQ), an index that provides a measure of multi-residue toxicity of contaminated pollen. Almost all pollen samples were contaminated by at least one compound. We detected 97 compounds, mainly fungicides, but insecticides and acaricides showed the highest toxicity. Fifteen % of the pollen samples had medium-high or high levels of PHQ, which could pose serious threats to honey bees. Fungicides showed a nearly constant PHQ throughout the season, while herbicides and insecticides and acaricides showed higher PHQ values in spring and early summer. Also, PHQ increased with increasing cover of agricultural and urban areas from April to July, while it was low and independent of landscape composition at the end of the season. The cover of perennial crops, i.e., fruit trees and vineyards, but not of annual crops, increased PHQ of pollen samples. Our work highlighted that the potential toxicity of pollen collected by honey bees was modulated by complex interactions among pesticide category, seasonality, and landscape composition. Due to the large number of compounds detected, our study should be complemented with additional experimental research on the potential interactive effects of multiple compounds on honey bee healt
Estimating the potential risk of transmission of arboviruses in the Americas and Europe: a modelling study
Get PDFBackground Estimates of the spatiotemporal distribution of different mosquito vector species and the associated risk of transmission of arboviruses are key to design adequate policies for preventing local outbreaks and reducing the number of human infections in endemic areas. In this study, we quantified the abundance of Aedes albopictus and Aedes aegypti and the local transmission potential for three arboviral infections at an unprecedented spatiotemporal resolution in areas where no entomological surveillance is available. Methods We developed a computational model to quantify the daily abundance of Aedes mosquitoes, leveraging temperature and precipitation records. The model was calibrated on mosquito surveillance data collected in 115 locations in Europe and the Americas between 2007 and 2018. Model estimates were used to quantify the reproduction number of dengue virus, Zika virus, and chikungunya in Europe and the Americas, at a high spatial resolution. Findings In areas colonised by both Aedes species, A aegypti was estimated to be the main vector for the transmission of dengue virus, Zika virus, and chikungunya, being associated with a higher estimate of R0 when compared with A albopictus. Our estimates highlighted that these arboviruses were endemic in tropical and subtropical countries, with the highest risks of transmission found in central America, Venezuela, Colombia, and central-east Brazil. A nonnegligible potential risk of transmission was also estimated for Florida, Texas, and Arizona (USA). The broader ecological niche of A albopictus could contribute to the emergence of chikungunya outbreaks and clusters of dengue autochthonous cases in temperate areas of the Americas, as well as in mediterranean Europe (in particular, in Italy, southern France, and Spain). Interpretation Our results provide a comprehensive overview of the transmission potential of arboviral diseases in Europe and the Americas, highlighting areas where surveillance and mosquito control capacities should be prioritise
A multi-indicator approach to compare the sustainability of organic vs. integrated management of grape production
Get PDFSustainable agricultural practices are increasingly becoming a strategic asset for global and national environmental policies and economy. A big challenge is the selection of appropriate indicators to describe the complexity of the agroecosystem management. In the present work, the sustainability of grape production, in vineyard trials of Pinot blanc and Rhine Riesling, managed with integrated (INT) and organic management (organic, with cattle manure ORG1 and organic with green manure ORG2), was compared using a multi-indicator approach. The experiment was set in 2011 (1.5 ha in Trento, Italy) and carbon footprint (CF), nitrogen footprint (NF), water footprint (WF), soil microbial diversity (alpha diversity of bacteria, fungi, oomycetes communities) and soil C stock change, were evaluated in 2018. The CF was 0.213—0.227 kg CO2-eq/kg in the INT, 0.144—0.168 kg CO2-eq/kg in ORG1 and 0.134—0.147 kg CO2-eq/kg in ORG2. The NF was around 1 g Nr/kg for the INT, 0.4 g Nr/kg for ORG1 and 0.5 g Nr/kg for ORG2. The WF, excluding the pesticides impact on grey water, was 666—708 L/kg for INT, 605—655 L/kg for ORG1 and 529—580 L/kg for ORG2. The impact of farming practices on soil microbial alpha diversity showed no significant difference among treatments for oomycetes and significantly higher indexes for fungi and bacteria in the ORG1, with INT and ORG2, being similar. No difference in bulk organic C were observed among treatments. Overall, the multi-indicator approach allowed to demonstrate that the organic management was more beneficial for most of the environmental spheres of the agroecosystem compared to integrated management, without affecting the grape yiel