Search results for "Spatial"
showing 10 items of 2121 documents
Structural analysis of woody species in Mediterranean old fields.
2008
The first part of this study provides an overview on Sicilian olive systems. Subsequently, the study describes the different typologies of cultivated agroforestry systems present in South-Eastern Sicily employing olive trees in association with other Mediterranean tree species, in particular for the production of firewood, coal and animal food (downy or pubescent oak, holm oak, cork oak), but also in association with forage or grazing species (oat, barley, vetch, etc.) or cereals. The study shows that Sicilian agroforestry systems are much more diversified than it was known so far. In the second part, the study describes the spontaneous colonization processes by plants, observed in abandone…
Gull-derived trace elements trigger small-scale contamination in a remote Mediterranean nature reserve
2013
The role of a yellow-legged gull (Larus michahellis) small colony in conveying trace elements (As, Cd, Cr, Cu, Ni, Pb, THg, V, Zn) was assessed in a Mediterranean nature reserve (Marinello ponds) at various spatial and temporal scales. Trace element concentrations in guano were high and seasonally variable. In contrast, contamination in the ponds was not influenced by season but showed strong spatial variability among ponds, according to the different guano input. Biogenic enrichment factor B confirmed the role of gulls in the release of trace elements through guano subsidies. In addition, comparing trace element pond concentrations to the US NOAA’s SQGs, As, Cu and Ni showed contamination …
A Multi-scalar Approach to Long-Term Dynamics, Spatial Relations and Economic Networks of Roman Secondary Settlements in Italy and the Ombrone Valley…
2019
AbstractIn Roman landscapes, the particular sites defined as secondary settlements (also known as vici/villages, minor centres, agglomérations secondaires and/or stationes/mansiones) have played an ‘intermediary’ role between the cities and other rural structures (villae/farms), linked to medium- and long-distance economic and commercial trajectories. The aim of this paper is to apply a multi-scalar approach to model their long-term spatial relationships and connectivity with the Mediterranean exchange network. On the macro-scale, we have analysed a sample of 219 reviewed sites to understand the diachronic trends and spatial dynamics of attraction/proximity to significant elements of the la…
Spatial relations of heavy metals in arable and greenhouse soils of a Mediterranean environment region (Spain)
2013
This study characterises and compares Cr, Ni, Pb, Cu, Zn and Cd (HMs) contents and the main edaphic parameters in arable soils (AS) from western areas of the Andalusian Autonomous Community (SE Spain) with greenhouse soils (GS) from the province of Almería, one of the most productive agricultural systems in Europe. We explored 199 GS and 142 AS, representing local and regional scales of variation in this important Mediterranean area. The hazardousness of HMs was particularly relevant in GS where agricultural practices, which centre on maximising production, end up with products that finally enter the human food chain directly. Despite their similar edaphic characteristics, the main differen…
Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin
2020
Producción Científica
The crisis facing Tunisian drainage tunnels: identification, analysis and evaluation of water heritage in the Mediterranean region
2014
In regions with Mediterranean and steppe climates, the presence of surface water is sporadic, and a unique – but fragile and undervalued – element of water capture for irrigation and human supply is the ‘qanats’, ‘foggaras’, ‘mkoulas’ or water tunnels. The central objective of this project has been the full study of Tunisia's drainage tunnels. The inventory, analysis and heritage evaluation of Tunisia's ‘qanats’ have been possible through the application of a particular methodology during four annual sessions of fieldwork and analysis in the geographic information system (GIS) laboratory. The results have been: the creation of a spatial data and cartography infrastructure for the Tunisian ‘…
Bioclimatology and Vegetation Series in Sicily: A Geostatistical Approach
2015
Tackling the Sicilian woody vegetation as a case-study, this work aims to verify the correspondence between Rivas-Martínez's bioclimatic units and the main vegetation series in the Mediterranean region. Following this approach, one macrobioclimate and 25 bioclimatic type belts can be recognized in Sicily. By means of a geostatistical analysis based on WorldClim data sets, cartographic models of the distribution range of each single bioclimatic unit were obtained and combined with vegetation data, in order to develop a new regional spatial framework, integrating climatic and vegetation data. Fidelity of each vegetation unit to a given climatic range was then evaluated as percent distribution…
Monitoring temporal changes in the spatial patterns of a Mediterranean shrubland using Landsat TM images
2001
Summary The overall goal of this study is to understand the structure and function of a Mediterranean shrubland at landscape scale by means of satellite images and GIS. Specifically, to assess the sensitivity of several spatial statistics to characterise landscape pattern, measure fragmentation and quantify the change through time. We study the landscape structure of a Mediterranean shrubland located in the east part of Spain (Valencia) and the change in spatial patterns of different shrubs types from 1984 to 1994. To accomplish these objectives, we used 10 Landsat™ images from 1984 to 1994 (except 1988) to which a geometric correction and an atmospheric normalization was applied. In additi…
Sea surface temperature and torrential rains in the Valencia region: modelling the role of recharge areas
2015
Abstract. Heavy rain events are frequently recorded in the Western Mediterranean causing economic losses and even human casualties. The Western Mediterranean is a deep and almost closed sea surrounded by high mountain ranges and with little exchange of water with the Atlantic ocean. A main factor in the development of torrential rains is ocean-atmosphere exchanges of heat and moisture that can potentially destabilize air masses travelling over the sea. The study of air mass trajectories previous to the rain event permits the identification of sea areas that could probably contribute to the development or intensification of rainfall. From a previous Mediterranean sea surface temperature clim…
A map of autumn precipitation for the third millennium BP in the Eastern Iberian Peninsula from charcoal carbon isotopes
2009
Abstract Carbon isotope composition (δ13C) in tree-rings has become routinely used in palaeoclimatic research for the assessment of changes in plant water availability in seasonally dry climates. However, the distribution of long tree-ring records around the world is very limited. Alternatively, the original climate signal of wood δ13C is well preserved in fossil charcoal and, accordingly, charcoal δ13C can be used to quantify past changes in water availability (e.g. precipitation). We report a case study on spatial palaeoclimate reconstruction which aims to characterize the transition between Bronze and Iron Ages, the so-called Iron Age Cold Epoch (ca. 900–300 BCE), using charcoals of Quer…