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Ecophysiology of Adonis distorta, a high-mountain species endemic of the Central Apennines
Get PDFMorphological, anatomical and physiological plant and leaf traits of A. distorta, an endemic species of the Central Apennines on the Majella Massif, growing at 2675 m asl, were analyzed. The length of the phenological cycle starts immediately after the snowmelt at the end of May, lasting 128 +/- 10 days. The low A. distorta height (H-max = 64 +/- 4 mm) and total leaf area (TLA= 38 +/- 9 cm(2)) associated to a high leaf mass area (LMA = 11.8 +/- 0.6 mg cm(-2)) and a relatively high leaf tissue density (LTD= 124.6 +/- 14.3 mg cm(-3)) seem to be adaptive traits to the stress factors of the environment where it grows. From a physiological point of view, the high A. distorta photosynthetic rates (P-N = 19.6 +/- 2.3 mu mol m(-2) s(-1)) and total chlorophyll content (Chl(a+ b) = 0.88 +/- 0.13 mg g(-1)) in July are justified by the favorable temperature. P-N decreases by 87% in September at the beginning of plant senescence. Photosynthesis and leaf respiration (R-D) variations allow A. distorta to maintain a positive carbon balance during the growing season becoming indicative of the efficiency of plant carbon use. The results could be an important tool for conservation programmes of the A. distorta wild populations
Ecophysiology of {Adonis} distorta, a high-mountain species endemic of the {Central} {Apennines}
No full textMorphological, anatomical and physiological plant and leaf traits of A. distorta, an endemic species of the Central Apennines on the Majella Massif, growing at 2,675 m a.s.l, were analyzed. The length of the phenological cycle starts immediately after the snowmelt at the end of May, lasting 128 ± 10 days. The low A. distorta height (Hmax= 64 ± 4 mm) and total leaf area (TLA= 38 ± 9 cm2) associated to a high leaf mass area (LMA =11.8±0.6 mg cm−2) and a relatively high leaf tissue density (LTD = 124.6±14.3 mg cm−3) seem to be adaptive traits to the stress factors of the environment where it grows. From a physiological point of view, the high A. distorta photosynthetic rates (PN =19.6 ± 2.3 μmol m−2 s−1) and total chlorophyll content (Chla+b = 0.88 ± 0.13 mg g−1) in July are justified by the favorable temperature. PN decreases by 87\% in September at the beginning of plant senescence. Photosynthesis and leaf respiration (RD) variations allow A. distorta to maintain a positive carbon balance during the growing season becoming indicative of the efficiency of plant carbon use. The results could be an important tool for conservation programmes of the A. distorta wild populations
The potentiality of Sentinel-2 to assess the effect of fire events on Mediterranean mountain vegetation
Get PDFWildfires are currently one of the most important environmental problems, as they cause disturbance in ecosystems generating environmental, economic and social costs. The Sentinel-2 from Copernicus Program (Sentinel satellites) offers a great tool for post-fire monitoring. The main objective of this study is to evaluate the potential of Sentinel-2 in a peculiar mountainous landscape by measuring and identifying the burned areas and monitor the short-term response of the vegetation in different 'burn severity' classes. A Sentinel-2 dataset was created, and pre-processing operations were performed. Relativized Burn Ratio (RBR) was calculated to identify 'burn scar' and discriminate the 'burn severity' classes. A two-year monitoring was carried out with areas identified based on different severity classes, using Normalized Difference Vegetation Index (NDVI) to investigate the short-term vegetation dynamics of the burned habitats; habitats refer to Annex I of the European Directive 92/43/EEC. The study area is located in 'Campo Imperatore' within the Gran Sasso – Monti della Laga National Park (central Italy). The first important result was the identification and quantification of the area affected by fire. The RBR allowed us to identify even the less damaged habitats with high accuracy. The survey highlighted the importance of these Open-source tools for qualitative and quantitative evaluation of fires and the short-term assessment of vegetation recovery dynamics. The information gathered by this type of monitoring can be used by decision-makers both for emergency management and for possible environmental restoration of the burned areas
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
HS-SPME-GC-MS Volatile Profile of “Aglio Rosso di Sulmona” (Sulmona Red Garlic) Floral Scape
Get PDFGarlic (Allium Sativum L.) is a source of organosulphur compounds with well-known sensorial and biological activity. Organosulphur precursors of garlic aroma are also detected in the plant leaves, but limited literature on this subject is available. This study is aimed at the characterization of the volatile profile of the floral scapes of Sulmona red garlic (aglio rosso di Sulmona) cultivated in the Abruzzo region (Italy). Floral scapes are manually removed from the plant before flowering and used as an ingredient of local gastronomy. The organosulphur volatile profile of the scapes is investigated by HS-SPME-GC-MS and compared to that provided by the clove. The GC-MS chromatogram of garlic clove, which is characterized by the predominant contribution of a few organosulphur organic compounds, is significantly more intense than that of the scapes. Almost all the organosulphur compounds contributing to the clove aroma were detected in the scape volatile profile, which, however, exhibits a more balanced contribution of major and minor organo sulphur compounds. Moreover, a significantly higher relative abundance of terpenes and aldehydes is observed in the scape aroma. The geographical/varietal origin of clove seeds (Sulmona versus Spain or France) and cultivation area interactively influence the aroma profile of Sulmona red garlic scapes
Carbon sequestration capability of Fagus sylvatica forests developing in the Majella National Park (Central Apennines, Italy)
No full textAbstract Terrestrial ecosystems represent a major sink for atmospheric carbon (C) and temperate forests play an important role in global C cycling, contributing to lower atmospheric carbon dioxide (CO2) concentration through photosynthesis. The Intergovernmental Panel of Climate Change highlights that the forestry sector has great potential to decrease atmospheric CO2 concentration compared to other sectoral mitigation activities. The aim of this study was to evaluate CO2 sequestration (CO2S) capability of Fagus sylvatica (beech) growing in the Orfento Valley within Majella National Park (Abruzzo,
Italy). We compared F. sylvatica areas subjected to thinning (one high-forest and one coppice) and no-management areas (two high-forests and two coppices). The results show a mean CO2S of 44.3 ± 2.6 Mg CO2 ha-1 a-1, corresponding to 12.1 ± 0.7 Mg C ha-1 a-1 the no-managed areas having a 28% higher value than the managed areas. The results highlight that thinning that allows seed regeneration can support traditional management practices such as civic use in some areas while no management should be carried out in the reserve in order to give priority to the objective of conservation and naturalistic improvement of the forest heritage
Lichens as monitors of the atmospheric deposition of potentially toxic elements in high elevation Mediterranean ecosystems
No full textIn this study we used a terricolous lichen (Cetraria islandica) as bioaccumulator of potentially toxic elements (PTEs) to explore spatial patterns of air pollutant deposition along elevational gradients in the Majella Massif (Italy). Samples of C. islandica were collected at 200 m intervals along 6 transects from 1600 to 2600 m, both along the eastern and the western slope of the Majella massif, and analyzed for their PTE content. The results supported the hypothesis that the deposition of PTEs to the Majella massif is largely influenced by elevation and slope. Two main patterns emerged connected either with local soil erosion and long-range atmospheric transport. For some PTEs, namely Al, Cr, Li, Mg, in the absence of any other data, it is supposed that the anthropogenic input is very small compared to the natural input from weathering processes. In contrast, the group of air pollutants subjected to long-range transport, as in the case of Cd, Hg, and Pb, has very limited local input and the main sources responsible for the higher concentrations on the eastern slope are probably to be searched in the Balkan area
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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