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1.
Sensors (Basel) ; 23(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36617109

RESUMO

The understory is an essential ecological and structural component of forest ecosystems. The lack of efficient, accurate, and objective methods for evaluating and quantifying the spatial spread of understory characteristics over large areas is a challenge for forest planning and management, with specific regard to biodiversity and habitat governance. In this study, we used terrestrial and airborne laser scanning (TLS and ALS) data to characterize understory in a European beech and black pine forest in Italy. First, we linked understory structural features derived from traditional field measurements with TLS metrics, then, we related such metrics to the ones derived from ALS. Results indicate that (i) the upper understory density (5-10 m above ground) is significantly associated with two ALS metrics, specifically the mean height of points belonging to the lower third of the ALS point cloud within the voxel (HM1/3) and the corresponding standard deviation (SD1/3), while (ii) for the lower understory layer (2-5 m above ground), the most related metric is HM1/3 alone. As an example application, we have produced a map of forest understory for each layer, extending over the entire study region covered by ALS data, based on the developed spatial prediction models. With this study, we also demonstrated the power of hand-held mobile-TLS as a fast and high-resolution tool for measuring forest structural attributes and obtaining relevant ecological data.


Assuntos
Ecossistema , Florestas , Biodiversidade , Lasers , Luz , Árvores
2.
Environ Monit Assess ; 190(12): 714, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30417241

RESUMO

Shifts in government priorities in response to the 2007 global recession have affected wildfire management and natural disaster funding arrangements, leading to a reduced effectiveness of fire suppression actions and increasing fire vulnerability. Our study investigates the role of local socioeconomic contexts on fire suppression effectiveness under economic expansion and recession in a Mediterranean region (Attica, Greece) strongly affected by 2007 crisis and displaying a persistently high density of peri-urban wildfires. Basic characteristics of wildfires (spatial distribution, intensity, and land use preferences) were investigated in the study area over two consecutive 8-year time intervals characterized by economic expansion (2000-2007) and recession (2008-2015). An integrated approach based on multivariate statistics and artificial neural networks was implemented to evaluate latent relationships between fire suppression time, wildfire characteristics, and socioeconomic dynamics. Controlling for wildfires' characteristics over the two time intervals, fire time length increased under crisis-mainly for small and medium-sized fires-possibly as an indirect response to reduced effectiveness of forest land management. Local contexts and political decisions influenced by economic downturns are relevant factors shaping wildfires' severity in the Mediterranean region. With recession, local contexts vulnerable to wildfires require more effective fire prevention measures, sustainable forest management, and regional planning.


Assuntos
Monitoramento Ambiental , Incêndios Florestais , Agricultura Florestal/métodos , Agricultura Florestal/tendências , Florestas , Grécia , Região do Mediterrâneo , Análise Multivariada , Redes Neurais de Computação , Fatores Socioeconômicos , Fatores de Tempo
3.
Environ Monit Assess ; 187(5): 283, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25903408

RESUMO

Topsoil organic carbon (TOC) and soil organic carbon (SOC) are fundamental in the carbon cycle influencing soil functions and attributes. Many factors have effects on soil carbon content such as climate, parent material, land topography and the human action including agriculture, which sometimes caused a severe loss in soil carbon content. This has resulted in a significant differentiation in TOC or SOC at the continental scale due to the different territorial and socioeconomic conditions. The present study proposes an exploratory data analysis assessing the relationship between the spatial distribution of soil organic carbon and selected socioeconomic attributes at the local scale in Italy with the aim to provide differentiated responses for a more sustainable use of land. A strengths, weaknesses, opportunities and threats (SWOT) analysis contributed to understand the effectiveness of local communities responses for an adequate comprehension of the role of soil as carbon sink.


Assuntos
Carbono/análise , Monitoramento Ambiental , Florestas , Solo/química , Agricultura , Ciclo do Carbono , Clima , Humanos , Itália
4.
Sci Total Environ ; 921: 171056, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382613

RESUMO

The distribution of species is primarily driven by the availability of trophic resources. In a given forest type, insects trophically related to the dominant tree are expected to be evenly distributed due to the abundance of their foodplant. However, their distribution is also influenced by complex relationships with abiotic and biotic parameters such as available space, predatory pressure, and morphometric traits. In this study, we investigated how the three-dimensional structure of space below the canopy may affect the composition of nocturnal lepidoptera communities. To synthesise the complexity of the dispersal behaviour of these insects, we evaluated easily measurable traits such as wingspan and the presence of tympanic organs, both connected to their mobility and thus potentially influenced by the structure of the available flight space. The study was conducted in the Sila National Park (Italy), where 12 sampling sites were selected in pine forests and an additional 12 in beech forests. Forest spatial structure was investigated using a portable terrestrial laser scanner. Moths were sampled monthly using light traps from May to October in both 2019 and 2020. Among measured forest traits, we observed that the space above three meters from the ground is the only factor influencing community composition. Larger species with tympanic organs prefer environments with less space below tree canopies. Our findings could be the starting point for future studies that investigate a potential defence strategy of moths against bats, as tympanate and larger species not only actively avoid chiropter predation but could also choose denser forests because of a lower bat activity. Moths' distribution and community composition thus appear to be significantly shaped by the spatial structure of forests.


Assuntos
Quirópteros , Mariposas , Animais , Florestas , Árvores , Fenótipo , Comportamento Predatório
5.
Sci Total Environ ; 890: 164281, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37216984

RESUMO

Wildfire regimes affected by global change have been the cause of major concern in recent years. Both direct prevention (e.g., fuel management planning) and land governance strategies (e.g., agroforestry development) can have an indirect regulatory effect on wildfires. Herein, we tested the hypothesis that active land planning and management in Italy have mitigated wildfire impacts in terms of loss of ecosystem services and forest cover, and burned wildland-urban interface, from 2007 to 2017. At the national scale, we assessed the effect size of major potential fire drivers such as climate, weather, flammability, socio-economic descriptors, land use changes, and proxies for land governance (e.g., European funds for rural development, investments in sustainable forest management, agro-pastoral activities), including potential interactions, on fire-related impacts via Random Forest modelling and Generalized Additive Mixed Model. Agro-forest districts (i.e., aggregations of neighbouring municipalities with homogeneous forest and agricultural characteristics) were used as spatial units of analysis. Our results confirm that territories with more active land governance show lower wildfire impacts, even under severe flammability and climatic conditions. This study supports current regional, national, and European strategies towards "fire resistant and resilient landscapes" by fostering agro-forestry, rural development, and nature conservation integrated policies.


Assuntos
Incêndios Florestais , Ecossistema , Itália , Tempo (Meteorologia) , Cidades
6.
Data Brief ; 34: 106617, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33344739

RESUMO

Vegetation structure is a key determinant of species distribution and diversity. Compared to traditional methods, the use of Terrestrial Laser Scanning (TLS) has allowed massive amounts of point cloud data collected for quantifying three-dimensional habitat properties at increasing spatial and temporal scales. We used TLS to characterize the forest plots across a broad range of forest structural diversity, located in the Sila National Park, South Italy. The dataset reports data collected in 24 15-m-radius circular plots, 12 of which were dominated by beech (Fagus sylvatica L.) and 12, by black pine (Pinus nigra subsp. laricio). In detail, this work provides dataset of i) plot-level attributes calculated from raw data, such as the number of trees, ii) tree-level data, comprising a total of 1709 trees, with information related to field-based forest inventory such as the diameter at breast height (DBH), and iii) plot-level information related to the time for conducting both traditional field- and TLS-based forest inventories. Compared to traditional methods, the use of TLS allows a very high-resolution quantification of the 3D forest structural properties, also reducing the time for conducting forest inventories.

7.
Sci Total Environ ; 654: 43-52, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30439693

RESUMO

Wildfires, a key socio-environmental challenge in Mediterranean regions, are influenced by anthropogenic factors shaping land-use and socioeconomic spatial structures. By assuming that the dominant socioeconomic structure of local districts exerts a variable impact on wildfire spatial regimes, the present study investigates 174 indicators on a municipal scale in Italy, identifying a multidimensional relationship between wildfire characteristics and socioeconomic contexts. An exploratory statistical approach was adopted to identify linear and non-linear relationships among variables assessing socioeconomic contexts and wildfire patterns. Empirical results demonstrate that characteristic wildfire attributes (frequency, intensity and severity) are systematically higher in socioeconomic contexts characterized by rural poverty, unemployment and deregulated urban expansion, especially in southern Italy. A higher fire frequency was typically observed in (i) peri-urban districts with a dynamic socio-demographic profile and (ii) in rural districts with intensive cropping systems. Joint information on socioeconomic structure/dynamics and environmental change, is crucial for a better understanding of local-scale spatial patterns of wildfires in the Mediterranean region. Integrated socio-environmental information provides a better understanding of the local communities' role in the management of wildfire-prone land, contributing to implement more effective strategies aimed at minimizing wildfire impact on land resources.

8.
Plants (Basel) ; 8(5)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075953

RESUMO

Developing adaptation strategies in Vitis vinifera, a crop sensitive to climate change, is crucial for resilience of traditional viticultural systems, especially in climate-vulnerable areas like the Mediterranean basin. A progressive warming is demonstrated to alter the geographical distribution of grapevine, reducing land capability for typical grapes and vine productions in most Southern European districts traditionally specialized in tree crops. Grapevine growth and reproduction under climate change require a continuous monitoring to adapt agronomic practices and strategies to global change. The present study illustrates an empirical approach grounded on a set of bio-physical indicators assessing the genotype-related response to climate variation. This approach was tested in Umbria, central Italy, to verify the response of some major international and local grapevine varieties to climate variation during a relatively long time interval (1995-2015). Long-term data for ripening time and berry quality collected in the study area were correlated to representative bioclimatic indices including Winkler, Huglin, and Cool night indicators. Results of this study highlighted the increase of air temperature (reflecting the inherent growth in thermal availability for maturation) and the alteration of precipitation patterns toward more intense precipitation. Climate variability exerted distinctive impacts on grapevine phenology depending on the related genotype. Empirical findings underline the usefulness of a permanent field monitoring of the relationship between selected climate variables and grape ripening with the aim to develop adaptive viticultural practices at farm's scale.

9.
J Mol Biol ; 396(1): 118-29, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-19917289

RESUMO

InfB-encoded translation initiation factor IF2 contains a non-conserved N-terminal domain and two conserved domains (G and C) constituted by three (G1, G2 and G3) and two (C1 and C2) sub-domains. Here, we show that: (i) Bacillus stearothermophilus IF2 complements in vivo an Escherichia coli infB null mutation and (ii) the N-domain of B. stearothermophilus IF2, like that of E. coli IF2, provides a strong yet dispensable interaction with 30 S and 50 S subunits in spite of the lack of any size, sequence or structural homology between the N-domains of the two factors. Furthermore, the nature of the B. stearothermophilus IF2 sites involved in establishing the functional interactions with the ribosome was investigated by generating deletion, random and site-directed mutations within sub-domains G2 or G3 of a molecule carrying an H301Y substitution in switch II of the G2 module, which impairs the ribosome-dependent GTPase activity of IF2. By selecting suppressors of the dominant-lethal phenotype caused by the H301Y substitution, three independent mutants impaired in ribosome binding were identified; namely, S387P (in G2) and G420E and E424K (in G3). The functional properties of these mutants and those of the deletion mutants are compatible with the premise that IF2 interacts with 30 S and 50 S subunits via G3 and G2 modules, respectively. However, beyond this generalization, because the mutation in G2 resulted in a functional alteration of G3 and vice versa, our results indicate the existence of extensive "cross-talking" between these two modules, highlighting a harmonic conformational cooperation between G2 and G3 required for a functional interaction between IF2 and the two ribosomal subunits. It is noteworthy that the E424K mutant, which completely lacks GTPase activity, displays IF2 wild-type capacity in supporting initiation of dipeptide formation.


Assuntos
Domínio Catalítico , Geobacillus stearothermophilus/metabolismo , Fator de Iniciação 2 em Procariotos/química , Fator de Iniciação 2 em Procariotos/metabolismo , Ribossomos/metabolismo , Substituição de Aminoácidos/genética , Dipeptídeos/metabolismo , Escherichia coli/crescimento & desenvolvimento , Genes Bacterianos , Teste de Complementação Genética , Geobacillus stearothermophilus/genética , Cinética , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Fator de Iniciação 2 em Procariotos/genética , Ligação Proteica , Biossíntese de Proteínas , Estrutura Secundária de Proteína , Subunidades Ribossômicas/metabolismo , Deleção de Sequência
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