68 research outputs found
A Sentinel-2 Based Multi-Temporal Monitoring Framework for Wind and Bark Beetle Detection and Damage Mapping
No full textThe occurrence of extreme windstorms and increasing heat and drought events induced by climate change leads to severe damage and stress in coniferous forests, making trees more vulnerable to spruce bark beetle infestations. The combination of abiotic and biotic disturbances in forests can cause drastic environmental and economic losses. The first step to containing such damage is establishing a monitoring framework for the early detection of vulnerable plots and distinguishing the cause of forest damage at scales from the management unit to the region. To develop and evaluate the functionality of such a monitoring framework, we first selected an area of interest affected by windthrow damage and bark beetles at the border between Italy and Austria in the Friulian Dolomites, Carnic and Julian Alps and the Carinthian Gailtal. Secondly, we implemented a framework for time-series analysis with open-access Sentinel-2 data over four years (2017–2020) by quantifying single-band sensitivity to disturbances. Additionally, we enhanced the framework by deploying vegetation indices to monitor spectral changes and perform supervised image classification for change detection. A mean overall accuracy of 89% was achieved; thus, Sentinel-2 imagery proved to be suitable for distinguishing stressed stands, bark-beetle-attacked canopies and wind-felled patches. The advantages of our methodology are its large-scale applicability to monitoring forest health and forest-cover changes and its usability to support the development of forest management strategies for dealing with massive bark beetle outbreaks
Singling out the place where rules apply: materials from the discussion on Panini’s description of substitution
No full textThis paper aims at taking Panini’s substitution descriptive method out of its supposed limited domain of allomorphy (Kiparsky 2009: 86), to show that it is rather part of a broader conceptualization of linguistic units in spatial terms, i.e. as “places” where “things” i.e. linguistic phenomena described by rules, happen (following the lead indicated by Kahrs (1998: 184)). In particular, while discussing on the thirteen dosavarttikas (vts. 18–30) on A. 1.1.56, by mainly relying on the textual dimension of the As..ta ̄dhya ̄y ̄ı and on the usus scribendi of the author, we advanced that Pa ̄n.ini’s linguistic units are not endowed with a mandatory fixed status, a misunderstanding which instead prevented ancient and modern interpreters (e.g. Joshi and Rood- bergen 1985, 1990) from solving these supposed shortcomings in the mechanism of substitution. On the contrary, he might have envisioned the different units as scalar categories, whose prototypes were verbal bases and affixes on the one hand and the single meaningless phoneme on the other. Consistently, Panini’s explicit classification of rules again is not abstract and functional but based upon the explicit mention of a relevant linguistic “place” and the way in which it is, each time, described: Panini’s strategy encompasses both devices to shift the status of a linguistic unit from phone to morph and vice versa
Porcine circovirus 2 (PCV2) and procine reproduction respiratory syndrome virus(PRRSV)co-expression in pigs with porcine dermatitis nephropathy syndrome (PDNS)
No full textLinee guida per la revisione del bilancio sociale
No full textIl bilancio sociale. Documenti di ricerca n°
On the Increasing Occurrence of a Green Christmas: A Perspective from Long-Term Eddy Covariance Observations on Winter Dormancy Interruptions in a Subalpine Forest
No full textSeasonal dormancy in temperate and boreal forests is an adaptive trait that guarantees tree survival during the winter season. This phenomenon is mainly affected by temperature and photoperiod (Heide 1974). However, increasing evidence suggests that winter dormancy is not a static state but rather a dynamic period influenced by intermittent warm spells that can temporarily reactivate ecosystem processes. These dormancy interruptions, particularly during "Green Christmas" events — characterized by reduced snow cover and anomalous winter temperatures — have the potential to alter seasonal carbon fluxes, shift forest phenology, and alter physiological cycles. As climate change intensifies, understanding the frequency and implications of these interruptions becomes crucial for predicting long-term shifts in ecosystem carbon dynamics and energy fluxes.Recent studies have reported that evergreen forests can initiate photosynthesis well before complete snowmelt (Bowling 2024), while deciduous forests exhibit a delayed response to warming trends. Additionally, Körner (2023) challenges conventional meteorological definitions of growing seasons, emphasizing that photosynthetic activity does not always align with temperature-based phenological markers. While there is strong evidence that climate warming influences seasonal carbon fluxes, long-term Eddy Covariance (EC) records reveal mixed trends in photosynthetic activity, suggesting that additional research is needed to uncover the underlying ecological and physiological mechanisms driving these shifts.As multiple EC flux tower sites established under the EUROFLUX project approach three decades of continuous observations, they offer a valuable opportunity to assess the long-term effects of climate variability on forest dormancy and carbon cycling. These extensive datasets allow for detailed trend analyses of winter dormancy interruptions, providing insights into their frequency, intensity, and potential impact on annual carbon sequestration.For this study, we selected the Renon-Selvaverde site (ICOS ID: IT-Ren, eLTER ID: BOL1), a subalpine forest with a long-term EC measurement record. To enhance the completeness of our dataset, we incorporated locally processed EC data, extending the NEE record from the Warm Winter Dataset (Gharun 2024) up to the present (1997-2024). Additionally, we ensured continuity in meteorological observations for the whole time span of our analysis.Leveraging this long-term dataset, we investigated how winter dormancy interruptions influence seasonal carbon dynamics. By integrating EC observations with environmental drivers, we aimed to refine our understanding of subalpine ecosystem responses to mid-winter warming events and evaluate their broader implications for carbon balance in the context of climate change.Winter dormancy interruptions were identified based on periods when NEE fluxes were significantly different from zero during the winter months. We then examined the relationships between NEE, shortwave radiation, soil temperature, and air temperature from the vertical profile during these interruptions. To quantify these interactions, we conducted a correlation analysis to assess the strength and significance of environmental drivers influencing ecosystem-level fluxes.Our analysis revealed an increase in the frequency of warm spells beginning in 2020. However, we did not detect a significant pattern in the duration of these events. Currently, warm spells appear to be isolated occurrences, allowing the forest stand to return to its dormant state after each event. Additionally, we observed that dormancy interruptions correspond to periods when soil temperatures remain above freezing and snow cover is absent, supporting the hypothesis that soil conditions play a critical role in determining ecosystem activity during winter. Anyhow, it is important to distinguish between warm spells characterized by non-freezing soil temperature (with or without snow cover) and photosynthetic activation driven by solar radiation but occurring under soil freezing conditions. In the latter case, photosynthesis may be initiated but remains constrained by water availability, with unclear effects on NEE.At present, these dormancy interruptions do not significantly impact the winter carbon budget of the observed ecosystem. However, we hypothesize that a continued increase in both the frequency and duration of warm spells could lead to fundamental shifts in seasonal or even annual carbon dynamics. An extended period of mid-winter photosynthetic reactivation could alter the seasonal carbon budget and potentially reduce the ability of subalpine forests to function as a long-term carbon sink, affecting their contribution to carbon neutrality.Future research should focus on mechanistic modelling approaches to predict long-term changes in carbon sequestration capacity under scenarios of increased winter warming and reduced snow cover
Study on the virulence, cell-mediated immune response and histolesivity of three field PRRSV strains with an ORF5 genetic variation
No full textABSTRACT
Aim of the study was to evaluate the virulence, cell mediated immune response and histolesivity of three PRRSV strains, with ORF5 relevant genetic variations, isolated from either respiratory and reproductive field outbreaks. Changes in peripheral lymphocytes showed a cytotoxic natural response more evident than the acquired cytotoxic one. The results, in our experimental conditions, evidenced a different behaviour among the three PRRSV strains. Two of them, the 55/L/2000 and 162/L/2000, were less virulent than the 418/FL/2003 strain and of another PRSSV field strain (114/L/2000) previously investigated. The three PRRSV strains studied had moderate virulence, similar cell mediated immune response, but different histolesivity
A predictive model for susceptibility to European spruce bark beetle (ips typographus) attacks: a case study of eastern South Tyrol
No full textThe thesis focusses on the European spruce bark beetle (Ips typographus) epidemics, phenomenon that is affecting and damaging several mountain forests of the northern hemisphere. The spread of these outbreaks has become a major concern in recent years, demanding effective management strategies. The study aims to predict the likelihood of bark beetle attacks by applying geostatistical analysis to several variables in the eastern South Tyrol region. More specifically, it examines the impact of the heavy snowfalls that affected the area of interest in 2019 and 2020, as well as the probability of attack in relation to topography, climate, forest structure (tree height), distance from previous infestations, tree species diversity, drought, and vegetation development. The data were collected from various platforms and subsequently standardized to rasters with a spatial resolution of 30 x 30 m, as well as standardized in terms of extent, and reference system using the R software. The logistic regression model utilized for the geostatistical analyses was also created and implemented using the R software. The conducted study confirms that the likelihood of bark beetle attacks increases in warm and dry climate. It also proves that future Ips typographus attacks are more likely to occur in previously infested areas. These findings can be fundamental for the implementation of future proactive management strategies and interventions in regions at higher risk of attack. However, this work is quite limited in terms of geographical extent and including data from the year 2023 could be important for validating the results and conducting further examinations. Thus, additional research is needed to confirm the robustness of the applied model and to generalize the outcomes of the analyses. Nonetheless, the created model could serve as a good starting point for further studies and validates geostatistics as a useful tool for analysing European spruce bark beetle epidemics
FEASIBILITY OF LAPAROSCOPIC INDOCYANINE GREEN (ICG)-GUIDED SENTINEL NODE BIOPSY IN OPEN ENDOMETRIAL CANCER SURGERY
No full textVIRULENZA, RISPOSTA CELLULARE EDISTOLESIVITÀ IN TRE CEPPI DI CAMPO DEL VIRUS DELLA “PORCINE REPRODUCTIVE RESPIRATORY SINDROME” (PRRS)
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