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Pubblicazioni Scientifiche
Filtri di ricerca 3 risultati
Pubblicazioni per anno
Forest structure and understory functional diversity at multiple scales: The importance of median tree height
de Benedictis
,
Luciano Ludovico Maria
,
Chelli
,
Stefano
,
Zhu
,
Zhengxue
,
Cervellini
,
Marco
,
Canullo
,
R.
,
Chianucci
,
Francesco
,
Puletti
,
Nicola
,
Tsakalos
,
James L.
,
Bartha
,
Sándor
,
Campetella
,
Giandiego
Early impact of alternative thinning approaches on structure diversity and complexity at stand level in two beech forests in Italy
Becagli
,
Claudia
,
Puletti
,
Nicola
,
Chiavetta
,
U.
,
Cantiani
,
Paolo
,
Salvati
,
Luca
,
Fabbio
,
Gianfranco
Mostra abstract
Stand structure, tree density as well as tree spatial pattern define natural dynamics and competition process. They are therefore parameters used to define any silvicultural management type. This work aims to report first data resulting from a silvicultural experiment in beech forests. The objective of the trial is testing the structure manipulation in terms of diversity and the reduction of inter-tree competition of different thinning approaches. Alternative thinning methods have been applied in two independent experimental sites located in the pre-Alps and southern Apennines, in Italy. Specific goals were to: (i) verify the impact early after thinning implementation on forest structure through a set of diversity and competition metrics resulting from a literature review; (ii) the sensitivity of tested indexes to detect effectively thinning manipulation. Main results show the low sensitivity of stand structure indexes and the ability of competition metrics to detect thinning outcome.
On the temporal mismatch between in-situ and satellite-derived spring phenology of European beech forests
Mostra abstract
Forest phenology plays a key role in the global terrestrial ecosystem influencing a range of ecosystem processes such as the annual carbon uptake period, and many food webs and changes in their timing and progression. The timing of the start of the phenology season has been successfully determined at a range of scales, from the individual tree by in situ observations to landscape and continental scales by using remotely sensed vegetation indices (VIs). The spatial resolution of satellites is much coarser than traditional methods, creating a gap between space-borne and actual field observations, which brings limitations to phenological research at the ecosystem level. Several unconsidered methodological and observational-related limitations may lead to misinterpretation of the timing of the satellite-derived signals. The aim of this study is therefore to clarify the meaning of a set of spring phenology metrics derived from Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time series in beech forests distributed across Europe with respect to PEP725 in situ observations, from 2003 to 2020. To this aim, we (i) tested the differences between remotely sensed and in situ start-of-season (SOS) metrics and (ii) quantified the influence of latitude, elevation, temperature, and precipitation on such differences. Results demonstrated that there is a clear temporal gradient among the different SOS metrics, all of them occurring prior to the in situ observations. Furthermore, latitude and temperatures proved to be the main factors guiding the differences between remotely sensed and in situ SOS metrics. Evidence from this study may help in recognizing the actual meaning of what we see by means of remotely sensed phenology metrics. In this perspective, field observations are crucial in understanding phenology events and provide a reference base. Satellite data, on the other hand, complement field observations by filling in gaps in spatial and temporal coverage, thus enhancing the overall understanding. © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.