96 research outputs found
Climate responses of long-lived woody species from the comfort zone to the outposts struggling for life
No full textClimate change is expected to cause profound effects in ecosystem structure, function, and distribution, particularly affecting long-lived woody species and forests, which will have to shift their distribution range to keep pace with relevant environmental changes. To address this challenge, new conservation strategies such as assisted migration must be implemented. However, effectively translocating woody species requires a thorough understanding of how forests respond to climate fluctuations throughout their distribution range.
This thesis aims to advance our knowledge in supporting the development of crucial conservation strategies by investigating growth patterns, ecophysiological strategies for coping with climate variability, and climate-growth relationships of long-lived woody species across their distribution range. The thesis, based on a retrospective approach that combines dendrochronology and dendroanatomy, is divided into three key research lines: i) assessment of the growth performance and climate sensitivity of several species within and outside their natural distribution range, ii) evaluation of climate-growth relationships and xylem structure in target species under optimal conditions, and iii) analysis of the climate responses of long-lived woody species at the edges of their distribution range, while assessing their suitability as proxies for climate reconstruction.
At the edges of the distribution, in Iceland, contrasting responses were found among species (Juniperus communis, Betula nana, Salix lanata, Betula pubescens, Sorbus aucuparia, Picea abies, and Pinus contorta) living under similar environmental conditions, underscoring the importance of species-specific ecological assessment for conservation strategies. Within the comfort zone, Picea mariana, a species native to present-day Canada, was analyzed by applying dendroanatomical techniques. Photosynthesis and carbon allocation were correlated to xylem traits, revealing a strong relationship between these two mechanisms. These dendroanatomical techniques were then analyzed in detail, comparing different approaches for dataset development and highlighting the high similarity between the two main protocols currently used in laboratories. Focusing on common juniper at the edge of its distribution range, this taxon revealed great potential as a paleoclimatic proxy, being identified as the oldest non-clonal shrub ever recorded in the tundra biome. Thanks to this unique characteristic, a reconstruction of July ground frost frequency for the past 1,200 years was possible. It showed a drastic reduction in frost frequency in the last century and, for the first time since the Viking Age, the complete absence of this phenomenon in 2021.
These findings provide a high-resolution, long-term, spatially comprehensive perspective on long-lived woody species’ growth habits. They offer insights into the ecophysiological strategies, and climate sensitivity of these species from the comfort zone to the outposts of their distribution ranges, offering insights into how certain forest woody species may respond to future climate scenarios. This thesis emphasizes the importance of these lines of research for the near future, while providing a sound foundation for crucial management strategies such as assisted migration
Congedi formativi ed altre occasioni di studio per i lavoratori
No full textISFOL, Cartei C., Frigo F., Grondoni G., Managheddu M., Nobili D., Premutico D., Satti E., Congedi formativi ed altre occasioni di studio per i lavoratori, Intervento a "Campagna informativa sui congedi formativi", 2007. Isfol OA: Learning object. Il documento, realizzato all'interno della campagna informativa della Regione Toscana, intende far conoscere uno strumento, il congedo formativo, regolamentato dalla legge 8 marzo 2000 n. 53, che consente ai lavoratori di assentarsi dal lavoro per ragioni di studio. 2007Regione Toscana, Ministero della Pubblica Istruzione - Ufficio Scolastico Regionale per la Toscanalearning object. il documento, realizzato all'interno della campagna informativa della regione toscana, intende far conoscere uno strumento, il congedo formativo, regolamentato dalla legge 8 marzo 2000 n. 53, che consente ai lavoratori di assentarsi dal lavoro per ragioni di studio. 2007 congedi formativi ed altre occasioni di studio per i lavoratori domenico nobili franco frigo davide premutic
Il sistema dell’offerta formativa nella Provincia di Firenze
No full textISFOL, Barricelli D., Frigo F., Premutico D., Ferri S., Simoni M.G., Il sistema dell’offerta formativa nella Provincia di Firenze, novembre 2004. Isfol OA: Technical Report. La ricerca offre uno spaccato significativo della situazione dell’offerta formativa della Provincia di Firenze relativamente ai progetti finanziati dal Fondo sociale europeo attraverso la Misura D1, dedicata alla formazione aziendale, negli anni 2002- 2003. 11/2004technical report. la ricerca offre uno spaccato significativo della situazione dell’offerta formativa della provincia di firenze relativamente ai progetti finanziati dal fondo sociale europeo attraverso la misura d1, dedicata alla formazione aziendale, negli anni 2002- 2003. 11/2004 il sistema dell’offerta formativa nella provincia di firenze domenico barricelli sergio ferri franco frigo davide premutico maria grazia simon
Characterization of Matrix Profile Technique for Enhanced Detection of Events in Sampled Values Data Streams
No full textIn the architecture described by IEC 61850 standards, merging units (MUs) and stand-alone MUs (SAMUs) are the initial elements in the measurement chain, with the main function of acquiring analog voltage and current signals, digitizing the samples and transmitting them to intelligent electronic devices (IEDs) for the evaluation of metrics of interest. Since they produce digital data, it is therefore possible to design extensions of their functionality that include data processing and the ability to identify events in the power grids. In this context, this article characterizes an event identification function to be implemented in MUs, based on the matrix profile (MP) technique and considering the Python library Stumpy. A comprehensive characterization of the MP technique is presented to evaluate its effectiveness for identifying discords in signals such as rapid events or voltage dips. The behavior of the MP technique is analyzed under different signal conditions and configurations, including variations in the number of samples per cycle and different window lengths. Noisy signals and challenging conditions such as overlapping events are considered. The MP performance is compared with other techniques used for discord detection in time series. The results obtained prove its robustness to noise and confirm its ease of use, needing only one parameter to operate
Utilizing Matrix Profile for Enhanced Detection of Events in Sampled Values
No full textThe merging units (MUs) serve as the critical interface between analog signals in power systems and digital instruments that process these data considering the IEC 61850 standards. Their primary function is to acquire digitized samples and transmit them to intelligent electronic devices for further processing. MUs are the first elements in the measurement chain capable of detecting events in the power system. In this context, this paper introduces an event identification function, to implement in the MUs, based on the matrix profile technique, which can effectively identify events such as voltage dips, even in noisy signal environments or when events overlap. The method can improve the reliability and accuracy of power quality monitoring and event detection in complex power system scenarios
Locke o Spinoza: un punto di eresia
No full textRelying on his previous inquiries, the author discusses theories of “consciousness” which were elaborated almost simultaneously by Locke and Spinoza, as a reaction against the Cartesian doctrine of self-certainty. Because of their remarkable analogies and their sharp antithesis, they illustrate a “point of heresy” which, even today, intrinsically divides any project of framing a “psychology” or “philosophy of mind
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Using the balanced scorecard framework /
No full text"... explains the balanced scorecard framework. Since its introduction in the early 1990s, the balanced scorecard framework has become a standard strategy execution and performance measurement system for many for-profit companies as well as for non-profit organizations and public sector entities. Scholars, including the author of this portfolio, Dr. Mark L. Frigo, have continued to refine this framework with cutting-edge managerial and accounting concepts.
Fausto Sozzini, la mortalità d’Adamo e la teologia moderna
No full textFausto Sozzini, Adam's Mortality and Early Modern Theology. In his dispute with Francesco Pucci, Fausto Sozzini argues that man was not created immortal but, being by nature subject to death, he could be made perpetually immune only through divine grace, which was a gift not included in his creation. It has thus been suggested that the Pucci-Sozzini querelle should be read as an expression of the broader debate that opposed the two 'souls' of modern theology, that is the Thomistic and the Augustinian. By reconstructing the late medieval theological debate on the mortality of Adam in the condition of innocence, the Author tries to show that Sozzini's theses are greatly indebted to Duns Scotus' criticisms of Thomas Aquinas
Frost rings frequency as indicator of increased frost susceptibility under current warming
No full textClimate change is observed and predicted to have a profound impact on forest ecosystems. Warmer conditions are one of the main drivers of recent increases in productivity and changes in structure and function observed in forests growing in temperature-limited environments. However, the extent of these changes is not homogeneous. With growing seasons lengthening but temperature variability increasing plants remains at risk of frost damage that could negatively affect plant growth.
This research aims to investigate the timing and occurrence of frost rings in tree species to get insight on how current warming impacts cold adaptation strategies in trees.
In this study, we investigate the sensitivity to frost events in three high altitude tree species Larix decidua Mill., Picea abies L., and Pinus cembra L. We analysed ring width time series of X individuals collected in from two sites in the Eastern Alps (Croda da Lago (BL) and Latemar (BZ) and identified frost rings. By considering daily temperature records, we were able to determine the day in which these frost rings had been formed.
Results show that for all the species at both sites, there is a trend of earlier frost ring formation over the last century and a half, shifting from late June in the mid-1800s to mid-May. This shift could confirm the earlier onset and lengthening of cambial activity, increasing the susceptibility time window of trees to frost damage. These findings provide valuable insights into cambial phenology, offering a deeper understanding of how shifting climate patterns influence the timing and activity of tree growth
Long-term eddy covariance fluxes and xylem anatomy for understanding carbon fixation in white pine woody biomass
No full textImproving our understanding of the carbon cycle is key to addressing the challenges of climate change. In this study, we investigated the relationships between intra and inter-annual climate variations, carbon fluxes, and the xylem biomass in an 80-year plantation of Pinus strobus at Turkey Point, Ontario, Canada. From eddy covariance tower, we obtained daily Gross Primary Production (GPP), precipitation and air temperature for the period 2003-2018. To determine inter-and intra-annual xylem biomass we selected 12 trees and built wood anatomical trait chronologies (cell lumen area, cell wall thickness, cell number, cell wall area and ring wall area) over the past 50 years. Using moving windows, we correlated all chronologies with daily climate data and GPP to analyse their associations at intra-annual scale.
The analysis showed that cell lumen area and cell wall thickness were strongly influenced by spring and summer temperature and precipitation. For the first time, we observed strong positive and significant correlations between GPP in the growing season and the cell wall area (which estimates the amount of carbon in each xylem cell) both in earlywood (May 10 - Aug 4, r = 0.685) and latewood (Jul 3 – Sep 3, r = 0.885). Strong positive correlations were also found between GPP and cell number and ring wall area. These results suggest a direct linkage between CO2 fluxes and the accumulation of carbon in woody biomass. This work will help to reconcile two important techniques that are widely used to study carbon sequestration in forests. It will help to reduce uncertainty in woody carbon accumulation and will open new perspectives in the study of the forest carbon cycle
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