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Modelling the seasonal dynamics of Aedes albopictus populations using a spatio-temporal stacked machine learning model
Full text linkVarious modelling techniques are available to understand the temporal and spatial variations of the phenology of species. Scientists often rely on correlative models, which establish a statistical relationship between a response variable (such as species abundance or presence-absence) and a set of predominantly abiotic covariates. The choice of the modeling approach, i.e., the algorithm, is itself a significant source of variability, as different algorithms applied to the same dataset can yield disparate outcomes. This inter-model variability has led to the adoption of ensemble modelling techniques, among which stacked generalisation, which has recently demonstrated its capacity to produce robust results. Stacked ensemble modelling incorporates predictions from multiple base learners or models as inputs for a meta-learner. The meta-learner, in turn, assimilates these predictions and generates a final prediction by combining the information from all the base learners. In our study, we utilized a recently published dataset documenting egg abundance observations of Aedes albopictus collected using ovitraps. and a set of environmental predictors to forecast the weekly median number of mosquito eggs using a stacked machine learning model. This approach enabled us to (i) unearth the seasonal egg-laying dynamics of Ae. albopictus for 12 years; (ii) generate spatio-temporal explicit forecasts of mosquito egg abundance in regions not covered by conventional monitoring initiatives. Our work establishes a robust methodological foundation for forecasting the spatio-temporal abundance of Ae. albopictus, offering a flexible framework that can be tailored to meet specific public health needs related to this specie
Quantifying West Nile virus circulation in the avian host population in Northern Italy
Full text linkWest Nile virus (WNV) is one of the most threatening mosquito-borne pathogens in Italy where hundreds of human cases were recorded during the last decade. Here, we estimated the WNV incidence in the avian population in the Emilia-Romagna region through a modelling framework which enabled us to eventually assess the fraction of birds that present anti-WNV antibodies at the end of each epidemiological season. We fitted an SIR model to ornithological data, consisting of 18,989 specimens belonging to Corvidae species collected between 2013 and 2022: every year from May to November birds are captured or shot and tested for WNV genome presence. We found that the incidence peaks between mid-July and late August, infected corvids seem on average 17% more likely to be captured with respect to susceptible ones and seroprevalence was estimated to be larger than other years at the end of 2018, consistent with the anomalous number of recorded human infections. Thanks to our modelling study we quantified WNV infection dynamics in the corvid community, which is still poorly investigated despite its importance for the virus circulation. To the best of our knowledge, this is among the first studies providing quantitative information on infection and immunity in the bird population, yielding new important insights on WNV transmission dynamic
Classification of farming systems by NMR widely targeted metabolomics: a cauliflower case study
Full text linkOrganic and conventional farming systems follow a set of specific rules and consumers usually pay an extra price for organic products, since they are associated with a higher quality. Nuclear magnetic resonance allows the analysis of the metabolome in a fast, non-destructive, and automatic way, with high coverage of chemical families and accurate quantification. Cauliflower corymbs obtained from two farming systems in two consecutive years were analyzed by 1H NMR and cultivation systems were correctly classified by this approach. Eleven and 3 metabolites showed significantly higher concentrations in organic corymbs in the first and second year, respectively, indicating the impact of cultivation year in the search for markers in organic produce. These included amino acids (alanine), purines (xanthine), organic acids, and N-containing compounds (choline), demonstrating their higher nutritional qualit
Effect of indigenous non-saccharomyces yeasts on lipid compositions of Maraština wine
Full text linkThis study is the first to investigate the impact of indigenous non-Saccharomyces yeasts, including Hypopichia pseudoburtonii, Metschnikowia sinensis/shanxiensis, Metschnikowia chrysoperlae, Metschnikowia pulcherrima, Lachancea thermotolerans, Hanseniaspora uvarum, Hanseniaspora guilliermondii, Hanseniaspora pseudoguilliermondii, Pichia kluyveri, and Starmerella apicola on the lipid composition of sterile Maraština grape juice and wines using the UHPLC-MS/MS method. Yeasts were tested in monoculture and sequential fermentations alongside commercial Saccharomyces cerevisiae. Indigenous non-Saccharomyces yeasts showed the potential to improve fermentation performance and enable the development of new wine styles through the biosynthesis of an unsaturated fatty acid pathway, which was identified as the most significant pathway. In monoculture fermentations, L. thermotolerans, H. uvarum, H. guilliermondii, H. pseudoguilliermondii, and P. kluyveri significantly reduced lignoceric acid, potentially influencing wine aroma through the formation of esters and higher alcohols. Hyp. pseudoburtonii, M. chrysoperlae, M. pulcherrima, P. kluyveri, and S. apicola increased the demand for lipids, such as stearic acid, which may help preserve membrane permeability by integrating into the membrane in response to ethanol shock. The most significant impact on free fatty esters was observed in fermentations with H. pseudoguilliermondii. Furthermore, L. thermotolerans in sequential fermentations significantly reduced arachidic, stearic, and palmitic acid. P. kluyveri reduced the content of erucic and linoleic aci
Understanding central European forest practitioners' requirements for remote sensing-based information products: a questionnaire survey
No full textDespite decades of development, the adoption of remote sensing-based information products in the forestry sector remains limited in central and southern Europe. This may partly be due to a mismatch between the developed remote sensing products and the needs of potential users. In this study, we present the results of a survey conducted with 355 forest practitioners from eight central and southern European countries. The survey aimed to identify practitioners’ technical requirements for four types of remote sensing-based information products: tree species, canopy height, wood volume/biomass, and forest disturbances. Respondents were asked about their preferences regarding thematic and spatial detail, the maximum acceptable error, and the temporal frequency of the information layers and for the main application fields of the information layers. The study also examined whether demographic variables of the participants including education, age, and professional background influenced these requirements. Preferences for spatial and thematic detail were found to be relatively diverse, whereas more consistent patterns emerged regarding error tolerances and temporal frequency demands. For example, the maximal acceptable error for detailed tree species maps was fluctuating between 5 and 15%, the maximal error of canopy height maps deemed acceptable by interviewees was between 1 and 3 m and the maximal acceptable error for biomass maps was between 5 and 20%. When comparing the demands of the practitioners with the current state-of-the-art in remote sensing, our results suggest that for some products, such as canopy height maps, existing remote sensing technologies and workflows can meet all practitioner demands. However, focusing on other information products, this is only partly the case: In our view, remotely sensed information on forest disturbances partially meets practitioner needs, while products related to tree species and wood volume/biomass currently fall short in terms of thematic detail and accuracy required by practitioners in central and southern Europe. The application fields for the information layers included well-expected tasks but the participants also named some quite unexpected “out-of-the-box” ideas of how to make use of remote sensing based information layers. These have so far been mostly ignored by the remote sensing community. With respect to the demographic groups, we found no statistically significant differences. While our results suggest that further technical innovation is still needed with respect to some information products to match the demands of the practitioners, it may also be questioned whether the demands are fully realistic. For example, it is well known that many traditional information products on which current forestry practices base on, do not reach the accuracy demanded by the practitioners. So, providing information products that are better than what practitioners are used to work with at the moment, may still create added value, even if the defined accuracy requirements are not matched. Our study contributes to our understanding of the alignment and misalignment between the technical requirements of forest practitioners and the capabilities of remote sensing-based information product
Exploring the role of climate change in toxic benthic cyanobacterial proliferation in Lake Lugano (Switzerland and Italy)
No full textFree-floating toxic cyanobacterial mats were observed for the first time in Lake Lugano (Switzerland and Italy) during the past two summers. The underlying causes of the rapid proliferation of benthic cyanobacteria remain unclear, and the potential negative effects on the ecosystem and water quality pose a new challenge for water management. Climate change is promoting the dominance of cyanobacteria in aquatic ecosystems; however, the effects on benthic species are still poorly understood. To investigate the source of cyanobacterial mats and the drivers of their proliferation in Lake Lugano, we conducted a study on the community structure and distribution of benthic cyanobacteria, focusing particularly on toxic species. We collected samples of cyanobacterial mats from the watershed of Lake Lugano and assessed their taxonomic composition using microscopy and high-throughput sequencing of the 16S rRNA amplicon sequence variants (ASVs). Cyanotoxins were quantified using liquid chromatography-mass spectrometry (LC-MS). The results were compared with the community structure and cyanotoxin profiles of floating mats and physicochemical variables. Our findings revealed that potential toxin-producing genera were widespread in benthic mats (e.g., Oscillatoria sp., Phormidium sp., Tychonema sp., Scytonema sp.). We observed distinct spatial distributions of anatoxin-producing and microcystin-producing cyanobacteria, which appeared to be influenced by different environmental variables (e.g., temperature, phosphorus levels, light availability). These results suggest that ongoing environmental changes could drive the future increase of toxic benthic cyanobacterial blooms. Although identifying the source of floating mats is challenging, the study emphasizes the urgent need for extensive research to identify high-risk areas and develop a management strategy to assist relevant authorities in mitigating the impact of these harmful blooms
DigiAgriApp: an open-source client-server application for centralized farming data management
Full text linkAgriculture is transitioning into the era of Agriculture 4.0, driven by data from IoT devices, sensors, and remote sensing tools. Efficient data collection and management are critical to improve farm productivity, sustainability, and resilience. DigiAgriApp is an open-source, client-server platform developed to centralize and streamline farm data management. It facilitates tracking of field operations, crop information, sensor data, irrigation, production statistics, and emissions, enabling precision farming at various scales
Le strategie di rivalità di Scaphoideus titanus (Hemiptera: Cicadellidae) dipendono dall’ampiezza dei segnali vibrazionali di accoppiamento
Full text linkScaphoideus titanus (Hemiptera: Cicadellidae) è noto per essere il principale vettore di Candidatus phytoplasma vitis, agente causale della flavescenza dorata nei vigneti. La riproduzione di questa specie si basa principalmente sulla comunicazione vibrazionale che consiste nell’emissione e ricezione di vibrazioni che si propagano attraverso la pianta. Il repertorio della specie è complesso, con diversi segnali che caratterizzano specifici stadi della formazione della coppia e due segnali vibrazionali specificamente emessi nei contesti di rivalità. Quando un maschio rileva un duetto maschio-femmina, può interferire con la comunicazione emettendo un rumore di disturbo (DN) o impulsi di disturbo (DP) per interrompere il duetto e sostituire il maschio duettante, riuscendo infine ad accoppiarsi con la femmina. Inoltre, i maschi rivali possono rimanere in silenzio e sfruttare le risposte della femmina per localizzarla prima dell'altro maschio e accoppiarsi (comportamento "satellite"). È noto che, nel processo di formazione della coppia, i passaggi da uno stadio all'altro si basano principalmente sull'ampiezza dei segnali percepita dal ricevente. Lo scopo di questo studio è valutare se anche la scelta della strategia di rivalità si basa sull'ampiezza dei segnali vibrazionali percepiti. Abbiamo condotto tre test di laboratorio: due test di playback e uno di osservazione. Nel primo test, abbiamo riprodotto un duetto sulla pianta utilizzando un trasduttore elettromagnetico, il trasduttore è stato posizionato sia sulla stessa foglia del maschio focale che su una foglia diversa, inoltre per ciascuna posizione abbiamo testato due playback con ampiezza diversa. Nel secondo esperimento, abbiamo testato se la posizione relativa del maschio focale rispetto alla posizione del maschio o della femmina influenzasse la risposta comportamentale. Abbiamo simulato le diverse sorgenti dei segnali maschili e femminili del duetto utilizzando due trasduttori, uno per ciascun sesso, posizionati su foglie diverse. Infine, abbiamo registrato il comportamento di un maschio focale quando un duetto si formava naturalmente tra un maschio e una femmina. I risultati hanno mostrato che la strategia adottata dal maschio rivale dipende dalla percezione dell'ampiezza dei segnali vibratori, suggerendo che il maschio può adattare la sua strategia di rivalità in base alla distanza percepita tra sé, l'avversario e la femmina. Discutiamo questi risultati alla luce delle conoscenze precedenti sui comportamenti di rivalità in altre specie basati sulla comunicazione vibrazionale o altre modalità di comunicazione. Inoltre, questi risultati saranno utilizzati per riflettere sul possibile sviluppo di abituazione alla tecnica di confusione sessuale vibrazional
Overwintering does not affect microbiota diversity in Halyomorpha halys: implications for its ecology and management
Full text linkHost-associated microbial communities play an important role in regulating many aspects of insect biology, but changes in this microbiota during diapause and overwintering are still largely unknown. Halyomorpha halys is an invasive agricultural pest characterised by a unique overwintering strategy where individuals aggregate and enter a state of dormancy, making it an excellent model to study the relationship between microbiota and diapause. We investigated the bacterial diversity of wild H. halys specimens before and after dormancy using 16S rRNA gene amplicon-sequencing. We found that microbiota varies between geographically neighbouring sampling locations, but there were no significant differences in microbial diversity or composition between populations sampled before and after diapause, despite stressful overwintering conditions. Such stability may relate to the highly specific taxa that dominate the stinkbug-associated microbial community. In addition, we did not detect any strong association of stink bugs with phytopathogens, but we found that two populations harboured Nosema maddoxi, a microsporidian pathogen of stink bugs. Our results are relevant to the assessment of accidental spillovers of microorganisms in newly invaded areas and to the implementation of the sterile insect technique based on mass trapping, irradiation, shipping and release after diapause of wild individual
