1,721,059 research outputs found
The Effect of Morphometry, Land-Use and Lithology on Landslides Susceptibility: An Exploratory Analysis
Full text linkGIS features provide simple and useful tools for landslides susceptibility and hazard studies, allowing the identification and the quantification of predisposing factors, and their relative importance. In lithologically homogeneous areas, the most influent factor of landslides is slope morphometry, in particular inclination, height and form. Moreover, within a hydrographic basin, landslides are coupled with drainage network. In fact landslides density and drainage density are positively correlated. Furthermore, human activity strongly influences the development of landslides. In our previous works, we introduced MSI (Morphometric Slope Index) as general index for slope morphometry, combining the main linear and areal morphometric features (area, form, length, inclination, width). Its formula is: MSI=A3D/A2D·L·Rc (where A3D is the three-dimensional area of the slope, A2D is its plan area, L is the slope length and Rc is the circularity ratio). We tested MSI as driver of different erosion landforms, demonstrating its influence in determining, on the one hand, the development and the final arrangement of calanchi drainage network (the typical Italian badlands), and, on the other hand, the erosion processes within them, mainly gullies and landslides. The present study is an exploratory application of this index to landslides susceptibility, aimed to analyze the combined effect of slope morphometry (summarized in MSI), lithology and land-use on the distribution of landslides in small catchments. The study is located in the Italian periadriatic foredeep, in the Abruzzo Region. This study has reinforced our perspective about the validity of the application of the techniques of geomorphometric analysis to the landslides susceptibility. Especially we consider this approach an efficient tool to summarize different controlling factors
Using MSI (Morphometric Slope Index) to find information about activation and evolution of calanchi in Italy
No full textThe role of the hillside in determining the morphometric characteristics of “calanchi”: The example of Adriatic central Italy
No full textA typical example of badlands in the Italian peninsula is the “calanchi” (plural of “calanco”), which may be
defined as rapidly evolving, very dense and hierarchical drainage systems whose genesis is controlled by
mineralogical characteristics, the granulometric composition of local lithotypes, structural conditions,
hillside gradient and climate. In this work some of the morphometric characteristics of the hillside were
compared on a statistical basis with those of the drainage network of the calanchi, for two large sample areas
in Adriatic central Italy. It was possible to demonstrate how the hillside environment strongly affects the
activation of the process and the characteristics of the calanchi, depending on their morphometric
morphometric characteristics. In particular, the length/inclination ratio of the hillside conditions the
hydrographic pattern of the calanco system
The morphometric slope index (MSI) as an indicator of landscape evolution: a multi-scale analysis
No full textOne of the main topics of the landscape evolution models is the hillslope-river relation studied by means of laboratory experiments, numerical or physical modelling and field studies. In this paper, we discuss the previous studies of the Authors about the index MSI (Morphometric Slope Index) with two main goals: to validate it as unique reference index for slope morphometry, and to give a unique model of the landscape evolution in some multi-scale drainage basins in Italy. Starting from reconstruction of the pre-erosion slope topography for three case studies at different scales, we perform a meta-analysis of the published data via bivariate statistics (correlation and regression) for detecting the influence of pre-erosion MSI on the characteristics of the drainage networks. Moreover, we introduce a new parameter for the characterization of the drainage networks.L’un des principaux sujets d’étude des modèles d’évolution du paysage porte sur la relation versant-rivière, étudiée par des moyens expérimentaux en laboratoire, des modèles physiques ou numériques et des études de terrain. Dans cet article, nous discutons des études portant sur l’indice morphométrique de pente (MSI) avec deux objectifs principaux : le valider comme unique indice caractérisant la morphométrie d’une pente et proposer un modèle unique d’évolution du paysage appliqué à plusieurs bassins hydrographiques italiens d’échelle différente. En partant de la reconstruction d’une pente pré-érosion pour 3 sites d’étude à différentes échelles, nous avons réalisé une méta-analyse des données publiées via des analyses statistiques bivariées (corrélation et régression) pour évaluer l’influence de l’indice MSI pré-érosion sur les caractéristiques des réseaux de drainage. Nous avons également introduit un nouveau paramètre pour la caractérisation des réseaux de drainage
La morfologia del versante in funzione dei processi morfogenetici in aree calanchive: l’esempio della Sicilia settentrionale
No full textGene expression profile in fibroblast growth factor 2-transformed endothelial cells.
No full textFibroblast growth factor-2 (FGF2) exerts paracrine and autocrine functions on endothelial cells. FGF2-overexpressing murine aortic endothelial cells (FGF2-T-MAE cells) induce opportunistic hemangioendothelioma-like tumors when inoculated in immunodeficient mice. To evaluate the impact of FGF2-mediated activation on gene expression profile in transformed endothelial cells, we performed subtractive suppression hybridization analysis between FGF2-T-MAE cells and parental MAE cells. The two cell populations were compared for differential gene expression also by gene macroarray hybridization with 32P-labeled cDNAs. The two approaches allowed the identification of 27 transcripts whose expression was upregulated by FGF2 in endothelial cells. With the exception of one unknown gene, the differentially expressed transcripts encoded for proteins involved in the modulation of cell cycle, differentiation, and cell adhesion. Among them, the stress-inducible genes A170, GADD45 and GADD153 are upregulated by FGF2 transfection or recombinant growth factor treatment. Their expression was also induced in vascular tumors originated by parental or FGF2-transfected MAE cells in nude mice. This study extends the number of genes involved in tumor angiogenesis and/or endothelial cell transformation, a finding with possible implications for the discovery of novel targets for angiostatic therapy
NMR-Metabolomic Study on Monocultivar and Blend Salento EVOOs including Some from Secular Olive Trees
No full textRelationships between a new slope morphometric index and calanchi erosion in northen Sicily, Italy
No full textThe Italian badlands, or “calanchi”, are common landforms in Mediterranean areas including central and
southern Italy. Calanchi landforms may be compared to small hydrographic basins. These landforms are
characterised by dense, hierarchical and rapidly evolving drainage systems carved into steep clayey slopes
and by a sharply alternating pattern of furrows and narrow, generally sharp crests.
This work presents a study of morphometric characteristics and a statistical analysis for two sites in northern
Sicily (Italy), on outcrops of silty-clay deposits affected by active erosion processes, which give this area a typical
calanchi landscape. In particular, factors closely linked to the characteristics of the hydrographic network and
slope morphometry were considered and analysed. The initial geometry of the slopes was reconstructed and
statistically compared with that of the current calanchi slopes including the drainage network.
A new morphometric index (Morphometric Slope Index, MSI) was defined to represent the initial slope geometry
as awhole. This indexwas found to be effective in defining the structure of hydrographic networks, summarising
the characteristics and type of slope evolution, and quantifying the rate of soil erosion. The rate was
determined based on both linear (gully erosion) and areal (landslides, sheet and rill erosion) morphogenetic
processes, and our analysis based on MSI indicates the dominance of areal erosion. MSI could also be used for
basins larger than calanchi to represent the characteristics of geomorphic processes
Geomorphometry for studying the evolution of small basins: an example in the Italian Adriatic foredeep.
No full textThe present work focused on the influence of pre-erosion
slope morphometry on the arrangement and evolution of small
basins in the Periadriatic belt of central Italy. MSI (Morphometric
Slope Index) was considered as general index for slope
morphometry and tested as geomorphometric driver of fluvial
erosion processes. Using two DEMs with different resolution (30 m
cell-size ASTER Global DEM and 10 m cell-size Italian TINITALY
DEM) and TauDEM toolbox within ArcGIS, we automatically
extracted watersheds and stream networks. We firstly proved their
validity through visual investigation and statistics, and analyzed the
effect of the different resolution on the morphometric parameters.
Subsequently, we analyzed the influence of MSI on both drainage
network and eroded volume through Regression Analysis and t-
Student Statistics using the DEM which was proved to be the most
correct. We reached the following main outcomes: (i) the slope
morphometric features combined in MSI strongly influenced the
amount of eroded material since the inception of fluvial erosion
process, (ii) the drainage density was linked to MSI by a
logarithmic trend, and (iii) this relation directly depended on
lithological features of the basins due to different lithotechnical
behavior of clay and conglomerate on which they were set. We
proposed a further advancement of this research focused on
geomorphological hazards, considering MSI as predictor, e.g., of
landslides, and developing a model for landslides susceptibility
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