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Pubblicazioni Scientifiche

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Pubblicazioni per anno
Intra-annual raw basal area increments (early-wood and late-wood) of Pinus nigra subsp. laricio Poiret trees from southern Italy at the pines׳ mesic to xeric distribution range
Mostra abstract
This article contains tree rings data related to the research article entitled “An intra-stand approach to identify intra-annual growth responses to climate in Pinus nigra subsp. laricio Poiret trees from southern Italy” (Mazza et al., 2018). Most dendroclimatological studies on black pine have been conducted on the P. nigra subsp. nigra, while only few results on climate-growth relationships are available for other taxa such as P. nigra subsp. laricio, which has the narrowest distribution range of the collective species P. nigra. This data article provides tree rings data for the subsp. laricio at an intra-annual growth level, distinguishing early-wood (EW) and late-wood (LW), from an even aged forest stand from the Sila mountain area within the subspecies mesic to xeric distribution range. © 2018
An intra-stand approach to identify intra-annual growth responses to climate in Pinus nigra subsp. laricio Poiret trees from southern Italy
Mostra abstract
The growth of Pinus nigra tree stands is known to be limited by spring-summer precipitation (P). We explored the intra-annual growth dynamics (early-wood EW and late-wood LW of tree-rings) and their responses to climate (in monthly, seasonal and annual scale) in Pinus nigra subsp. laricio at the intra-stand level in Calabria, at the pines' mesic to xeric distribution range. We used a variety of age detrending methods to assess how the adaptive potential to climate change of each tree varies within the even-aged forest stand. In years of wet climate, when precipitation (P) could infiltrate deeper below ground, higher growth rates occurred in 83% of trees, best explained by P accumulated over several previous years. The variability of EW increment was best explained by 3–5 previous year P (including the growth year) in 61% of trees, while LW increment was best explained by 1–3 year P in 78% of trees. This would suggest that in wet years most trees utilized not only surface but also deeper moisture pools using their taproot to produce both EW and LW. In contrast, during dry years, for 39% of trees the most significant predictor for EW was June rainfall. August P explained LW variability in 35% of the trees, while the influence of 1–3 year P on LW was reduced to 48%. Thus, under a drier climate ca. 1/3 of the trees within the stand significantly reduced their capacity to utilize deeper ground moisture, indicating higher vulnerability to drought stress. Multiple-year P appeared as the main climatic driver for growth in most trees, but only became evident through age detrending methods retaining low frequency growth variability. Our findings are the first to provide such insight into the wide spectrum of climatic factors that may drive P. laricio's inter-stand and inter-annual productivity. They also assist to identify the most vulnerable trees to drought stress within a forest stand. Such information could prove very useful in the application of silvicultural treatments (e.g., selective thinning) aiming to increase the resilience of tree stands to future drought intensification. © 2018 Elsevier B.V.
Sustainable land-use, wildfires, and evolving local contexts in a Mediterranean Country, 2000-2015
Mostra abstract
Socioeconomic conditions and land management choices combine to affect changes in long-term wildfire regimes in Mediterranean-type ecosystems. Identification of specific drivers and dynamics at the local level is needed to inform land resource planning and to enhance wildfire management efficiency. Therefore, investigating feedback relationships between wildfire and socioeconomic conditions at local and regional scales can reveal consistency in spatial and temporal patterns influencing wildfire frequency, intensity, and severity. This study assessed long-term wildfire characteristics in Greece-one of the most fire-prone countries in Europe-over two consecutive time periods characterized by economic expansion (2000-2007) and recession (2008- 2015). An integrated, multivariate statistical approach was implemented to assess the latent relationship between socioeconomic forces and localized wildfire regime indicators. Changes in the number of fires at the wildland-urban interface and duration of wildfires were consistent with expectations. Observed changes in the size of fires showed mixed results. Empirical findings of this study indicate analysis of wildfire regimes that takes into account both the socioeconomic and environmental factors in the overall territorial context of Mediterranean-type ecosystems, at both regional and local scale, may prove informative for the design of wildfire prevention measures in Greece. © 2018 by the authors.
An objective image analysis method for estimation of canopy attributes from digital cover photography
Mostra abstract
Key message: A method was proposed to remove the subjectivity of gap size analyses approaches implemented by default in cover photography. The method yielded robust and replicable measurements of forest canopy attributes. Abstract: Digital cover photography (DCP) is an increasingly popular method to estimate canopy attributes of forest canopies. Compared with other canopy photographic methods, DCP is fast, simple, and less sensitive to image acquisition and processing. However, the image processing steps used by default in DCP have a large substantial subjective component, particularly regarding the separation of canopy gaps into large gaps and small gaps. In this study, we proposed an objective procedure to analyse DCP based on the statistical distribution of gaps occurring in any image. The new method was tested in 11 deciduous forest stands in central Italy, with different tree composition, stand density, and structure, which is representative of the natural variation of these forest types. Results indicated that the new method removed the subjectivity of manual and semi-automated gap size classifications performed so far in cover photography. A comparison with direct LAI measurements demonstrated that the new method outperformed the previous approaches and increased the precision of LAI estimates. Results have important implications in forestry, because the simplicity of the method allowed objective, reliable, and highly reproducible estimates of canopy attributes, which are largely suitable in forest monitoring, where measures are routinely repeated. In addition, the use of a restricted field of view enables implementation of this photographic method in many devices, including smartphones, downward-looking cameras, and unmanned aerial vehicles. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.