91 research outputs found

    Modifiche compositive e strutturali in soprassuoli in evoluzione naturale della riserva M.a.B. di Montedimezzo (Isernia)

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    Tree species composition and structural dynamics in forest stands under natural evolution in the Montedimezzo M.a.B. reserve. This study is included in an experimental protocol established in 1954 aimed at examining the natural dynamics in mixed broadleaves high forests dominated by Turkey oak (Quercus cerris L.) and beech (Fagus sylvatica L.). Stand development patterns in the last fifteen years are reported. Repeated quantitative and qualitative inventories were carried out in two permanent plots (3 ha each) and in two structural transects (0.2 ha each) located in Collemeluccio-Montedimezzo M.a.B. reserve (Is). The study highlighted, as already observed in 1954, the differences between the two multilayered stands. In the higher elevation beech is the predominant species recording 53% of importance value index (I), followed by Turkey oak (I=25%). In the lower elevation the dominant species is Turkey oak (I=46%), followed by hornbeam (Carpinus betulus L.) (I=28%) and beech (I=12%). The decreased presence of Turkey oak and the increase of beech density are confirmed in each plot over the last fifteen years. Among the other tree species, importance values rise only for silver fir (Abies alba Mill.) (introduced) and holly tree (Ilex aquifolium L.), while hornbeam and hedge maple have been reducing their own presence

    Tree canopy cover and natural regeneration into strictly-protected forest areas: the MaB reserve of Montedimezzo (Isernia,Italy).

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    The ecological analysis and the analysis of mechanisms underlying the natural regeneration process into strictly protected forest areas, is basic to the understanding of ecosystem functioning and to estimate the recovery ability as a function of time and environmental changes. Aim of the paper is to analyze the spatial-temporal dynamics of tree species regeneration into mixed Turkey oak-common beech stands growing undisturbed since more than one half- century. The ability of first establishment and following growth of natural regeneration related to the ecological parameters, the structural features of standing crop and its development stages, are analyzed in detail. The study was carried out into two permanent monitoring plots (A) and (B) where two different tree species play the main functional role. In (A) common beech is dominant (Fagus sylvatica L.-elevation 1040 m a.s.l.); in (B) Turkey oak is prevailing (Quercus cerris L.-elevation 940 m a.s.l.). In each plot, the analysis of vertical stand structure, of natural regeneration pattern and ecological surveys (LAI, trasmittance, soil moisture content, canopy interception of rainfall) were undertaken by monthly surveys from May to October into 57 sub-plots each 1m2 wide over the period 2005-2007. Results highlighted that (B), Turkey oak prevailing, shows a more complex structure, a higher tree canopy thickness and the lack of gaps. The area shows therefore a lower trasmittance and a higher LAI value; throughfall and soil moisture content are also reduced as compared to (A). As for the natural regeneration pattern, further to a first stage when seedlings mortality is high, their survival rate is being kept high and steady over time in (A). A further mortality peak has been detected vice versa over the following summer season in (B). The different main tree species composition and radiation regime seem to be the basic reasons of the dynamics observed as for mortality and survival rates. The way of seedlings establishment points out that optimal ecological conditions are present for the production and germination of seeds as well, but that the limiting factor is the reduced radiation amount that reaches the forest floor.

    Comparison between crown thinning and girdling to enhance sporadic tree species in a coppice stand in Central Italy

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    Sporadic valuable tree species and especially Sorbus species have gained importance in forest management as they increase tree biodiversity, ensure a higher resilience of the stand to climate change, and enhance valuable timber production. This paper reports the first results of a trial carried out in Central Italy in a Turkey oak coppice stand (aged 17 years) where three different silvicultural treatments (crown thinning, girdling and unthinned control) were applied to favour sporadic tree species. The monitoring was carried out for 5 years and showed the limits of girdling application as Mediterranean species like Turkey oak form easily scar cords and epicormic sprouting. Furthermore, the progressive reduction of canopy cover of the competitors resulted from girdling and the effect of the thinning and girdling on the growth of selected service trees (Sorbus domestica L.) were evaluated. The first results of this research have pointed out some difficulties in the girdling application and a higher effect of crown thinning in stimulating the growth of selected service trees

    Sodium Nitrite Intoxication and Death: Summarizing Evidence to Facilitate Diagnosis

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    Background: Over the years, forensic pathology has registered the spread of new methods of suicide, such as the ingestion of sodium nitrite. Sodium nitrite causes increased methemoglobin, resulting in systemic hypoxia, metabolic acidosis, and cyanosis. Since sodium nitrite is a preservative, the ingestion of foods containing an excessive amount of this substance can also cause acute intoxication up to death. The present review is aimed at guiding health professionals in the identification and management of sodium-nitrite-related intoxications and deaths. Methods: A systematic literature search was carried out on PubMed by following the PRISMA statement’s criteria. A total of 35 studies with 132 cases were enrolled, and the data were cataloged in Microsoft Excel. To establish the causal correlation between sodium nitrite ingestion and death, the Naranjo Adverse Drug Reaction Probability Scale was used. Results: In addition to the small number of cases that have currently been published, the study demonstrated that there was a general methodological discrepancy in the diagnostic process. However, some interesting results have emerged, especially in post-mortem diagnostics. Conclusion: Sodium-nitrite-related deaths represent a challenge for forensic pathologists; therefore, it is important to promptly recognize the essential features and perform the necessary and unrepeatable examinations for the correct diagnosis of the cause of death

    Tree Species Composition in Mixed Plantations Influences Plant Growth, Intrinsic Water Use Efficiency and Soil Carbon Stock

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    Species interactions in mixed plantations can influence tree growth, resources capture and soil fertility of the stands. A combined approach of tree-ring analyses and carbon stable isotope was used to check tree growth and water use efficiency of two species, Populus alba L. and Juglans regia L., intercropped with each other and with N-fixing or competitive production species. Furthermore, soil analyses were performed to understand how the different intercropping systems can influence soil characteristics, in particular soil carbon stock. Dendrochronological data showed that during the first years, the growth of principal species was favored by intercropping. This positive effect decreased in the following years in most of intercropped stands, due to light competition with the crown of companion species. Carbon isotope data showed that P. alba and J. regia had the highest intrinsic water use efficiency when growing with Elaeagnus umbellata Thunb, a shrubby species with a shallow root system that favors a non-competitive exploitation of soil water resources. Finally, the intercropping of the principal species with Corylus avellana L. promoted the highest soil C stock. Our findings confirmed the importance to consider the plantation dynamics and wood formation in the long-run and to apply appropriate thinning and pruning interventions to counteract interspecific competition

    The GIS database of WOODnat project for the inventory and monitoring of walnut plantations in Italy and Spain

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    Within the activity of the H2020 ‘WOODnat’ project (“Second generation of planted hardwood forests in the European Union”) the growth parameters, yield and sanitary conditions of the most important walnut (Juglans spp.) plantations, established in Italy in the 1990s and in Spain starting from 1996, were recorded. One of the objectives of the project was to evaluate tree growth and stem quality to derive insight on the main environmental factors affecting the production of this valuable specie. An inventory of walnut plantations in the area of interest was necessary due to the relevance of this tree species in the EU timber market. In this paper the final dataset is presented and available with DOI: 10.5281/zenodo.3769940. The database is finalized to narrow the knowledge gap between growers and processing industry with the aim to relaunching the market for this valuable species. Data were collected in the spring 2017 and winter 2017-2018 on 27 stands established in Northern Italy (Piemonte and Lombardia), on 51 stands in Central Italy (Toscana and Marche) and on 17 stands in Spain for a total of 95 plantations. In each plantation, general information was collected such as the planting layout, spacing, age, environment conditions as well as tree-level dendrometric data and phytosanitary information. The sampled stands have been georeferenced in WGS84 reference system (EPSG 4326). These data can be exploited to assess potential wood volume obtainable and quality of raw material, and to identify the weaknesses and errors, strengths and opportunities of the experiences conducted to plan future plantings with greater awareness

    Enhancing chestnut coppices: silvicultural management and socio-economic context.

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     Castanea sativa is one of the most important species for timber production in Italy but, both management system, ownership type and wood chain structure, aren’t able to  enhance enough the market value of wood assortments. Although the high demand of quality timber, the internal production is heavily  reduced, mainly as far as timber quality is concerned and because of the lack of suitable timber sizes. In this context, experimental trials  have been approached to identify and verify which silvicultural methods are best suited to reach high yields depending to the investments  needed and the local socio-economical condition. Two technical approaches were evaluated: stand silviculture and single-tree oriented silviculture. As for the socio-economical aspects, a few demographic indexes have been examined and the first-phase processing enterprises  acting in the concerned area were analyzed. The goals of this paper are to evaluate the biological response to the applied silviculture, to  analyze the problems arisen and to estimate the applicability of the proposed methods in relation to the different socio-economic contexts. The research has been carried out in Tuscany in two important forest areas - Monte Amiata and Colline Metallifere - in young chestnut  coppices characterized by an homogeneous stand density and a good site index. The two examined districts showed some similarities  but they have mainly highlighted important differences about the social structure and concerns and enterprises characteristics. The area of Monte Amiata is typified by a higher residents density then the Colline Metallifere but only 1/3 of the population is employed in the agro-forest sector. In addition, in the Monte Amiata district most concerns are sized less than 2 hectares and chestnut is the main forest  species. On the contrary, in the Colline Metallifere the agro-forest sector (57% of workers) is one of the main sources of income for the  local communities and medium-sized concerns are noteworthy present. Chestnut stands have here a marginal role, oaks are dominant  and the prevailing assortment is firewood. From a silvicultural viewpoint, both the studied areas showed a quite good potentiality, suitabl

    Adoption of new silvicultural methods in Mediterranean forests: the influence of educational background and sociodemographic factors on marker decisions

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    Producción Científica- Key message The adoption of new silvicultural methods and approaches requires an understanding of the differences between those and “old” or “conventional” approaches, along with extensive training to break previous knowledge bias. - Context Forestry is in transition towards ecosystem-based management, and new silvicultural approaches are appearing worldwide. However, the adoption of an alternative silvicultural approach is difficult in practice. - Aims We analyzed the effect of forestry background and demographic variables (gender and age) of 24 raters on the application of the systemic approach (SA) and the conventional approach (CA) in the Northern Apennines (Italy) and compared this with tree marking performed by experts. - Methods Data were analyzed as raters’ departures from experts’ selections at the stand and the individual tree level. The probability of tree selection was also calculated. - Results At the stand level, raters with forestry background performed the SA as if they were marking for crown thinning, whereas the CA was less intense than experts’ crown thinning. Non-foresters differentiated poorly between the SA and the CA. At the individual tree level, background and gender affected tree selection. - Conclusion The adoption of the SA as a silvicultural system may be conditioned by previous knowledge. The difference between SA and CA remains unclear when it comes to non-foresters. Gender was a more important variable than age in selecting which trees would be harvested

    Label-free multimodal nonlinear optical microscopy reveals features of bone composition in pathophysiological conditions

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    Bone tissue features a complex microarchitecture and biomolecular composition, which determine biomechanical properties. In addition to state-of-the-art technologies, innovative optical approaches allowing the characterization of the bone in native, label-free conditions can provide new, multi-level insight into this inherently challenging tissue. Here, we exploited multimodal nonlinear optical (NLO) microscopy, including co-registered stimulated Raman scattering, two-photon excited fluorescence, and second-harmonic generation, to image entire vertebrae of murine spine sections. The quantitative nature of these nonlinear interactions allowed us to extract accurate biochemical, morphological, and topological information on the bone tissue and to highlight differences between normal and pathologic samples. Indeed, in a murine model showing bone loss, we observed increased collagen and lipid content as compared to the wild type, along with a decreased craniocaudal alignment of bone collagen fibres. We propose that NLO microscopy can be implemented in standard histopathological analysis of bone in preclinical studies, with the ambitious future perspective to introduce this technique in the clinical practice for the analysis of larger tissue sections
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