Search results for " basin"
showing 10 items of 838 documents
5. Introduction — palaeoclimate reconstructions and dating
2007
Publisher Summary This chapter describes four interglacials preceding the Holocene—that is, during the time from about 100 to 450 kyr. The first knowledge on this time has been extracted almost 40 years ago from marine deep sea cores with a sampling resolution of several thousand of years. Deep ocean sediments can be easily dated, because δ18O stratigraphy can be applied all over the ocean basins and tuned directly to the ice volume/sea-level master curve of SPECMAP, which is based on the beat of the orbital insolation cyclicities. This dynamic climate evolution of the past interglacial must have been of high importance also for the evolution of mankind. Neanderthal hominids lived and hunte…
Tracking environmental changes in restored Mediterranean dune slacks.
2019
Restoration is an ecological tool that aims to recover the prior conditions and functioning of a degraded habitat. Three restoration projects targeted a dune slack system in the Eastern Iberian Peninsula and created a mosaic of ponds restored over three different periods: 1998, 2003 and 2007, the latter coinciding with the start of our study. Restoration works consisted of digging out the pond basin to its original morphometry. We monitored 12 restored ponds (six recent, three intermediate and three older ones) monthly, over four consecutive hydrological years (from 2007 until 2011) characterizing the most important limnological factors in order to disentangle the effects of man-made restor…
Suspect, non-target and target screening of emerging pollutants using data independent acquisition: Assessment of a Mediterranean River basin
2019
A single workflow based on three approaches (target, suspected and non-target screening) using liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) in data independent acquisition mode (DIA) was developed to assess the presence of emerging pollutants (EPs) in water and sediments from a Mediterranean River Basin. Identification of potential contaminants was based on mass accuracy, isotopic ratio pattern, theoretical fragmentation, and retention time using Waters UNIFI software. In the suspect screening against a library containing 2200 components, 68 contaminants were tentatively identified, 6 of which were confirmed and quantified with analytical standar…
Energy planning methodology of net-zero energy solar neighborhoods in the Mediterranean basin
2016
The article proposes a simplified methodology to optimize solar energy gains at district level in the Mediterranean area toward the achievement of the net-zero energy district target, to be applicable as well in similar hot climates. The approach includes a wide use of parametric analysis to explore the most impactful aspects of the design of solar net-zero energy districts: single unit shape, building mutual distances, road shape, building orientation, photovoltaics area availability to identify the optimal design solution. Thirty-two different district configurations are explored: results show that in the Mediterranean context, it is possible to reach the net-zero energy district target i…
Epiphytic bryophytes in harsh environments: theJuniperus thuriferaforests
2010
SUMMARY The forests of Juniperus thurifera are peculiar ecosystems that typically grow on mountains and highplateaux of the western Mediterranean basin with dry and continental climates. Some previous surveys suggested that these forests house a rather distinctive epiphytic bryophyte flora. Epiphytic bryophyte communities were systematically sampled in 19 representative juniper forests, for the first time spanning all the distribution area of this conifer. The flora consists of 44 species (32 acrocarpous mosses, 10 pleurocarpous mosses and 2 liverworts). Orthotrichum species are the most frequent and abundant in most of the sampled localities, including some uncommon taxa such as Orthotrich…
Geographical patterns of genetic variation in rosemary (Rosmarinus officinalis) in the Mediterranean basin
2013
Climate changes during the Quaternary had important effects on the evolution of European plant species. The distribution of genetic variability in rosemary, a strictly Mediterranean species of reputed Plio-Quaternary origin for which the diversification centre is hypothesized to be located in the western part of the Mediterranean basin, was investigated across the species range by using plastid microsatellites (plastid simple sequence repeat (cpSSR)) markers. Seven out of the 17 primer pairs screened were polymorphic, with up to four alleles, yielding a total of 17 size variants combined into ten haplotypes. A permutation test to investigate for geographical structure showed no significant …
Pressure-Knapping Blade Production in the North-Western Mediterranean Region During the Seventh Millennium cal B.C.
2012
A review of selected Mesolithic blade and trapeze complex series in the north-western Mediterranean reinforces the hypothesis of a common use of pressure techniques for bladelet production during the seventh millennium cal B.C. This paper deals with the specificity and variability of these techniques and the consistency of the blade production methods. Mesolithic pressure technique seems to have been quickly diffused within the western Mediterranean basin, earlier than the spread of Early Neolithic communities in the same area. It then proceeded from a regional development, distinct from the Mesopotamian and Anatolian cores.
Perfluoroalkyl substances in the Ebro and Guadalquivir river basins (Spain).
2015
Mediterranean rivers are characteristically irregular with changes in flow and located in high population density areas. This affects the concentration of pollutants in the aquatic environments. In this study, the occurrence and sources of 21 perfluoroalkyl substances (PFASs) were determined in water, sediment and biota of the Ebro and Guadalquivir river basins (Spain). In water samples, of 21 analytes screened, 11 were found in Ebro and 9 in Guadalquivir. In both basins, the most frequents were PFBA, PFPeA and PFOA. Maximum concentration was detected for PFBA, up to 251.3ngL-1 in Ebro and 742.9ngL-1 in Guadalquivir. Regarding the sediments, 8 PFASs were detected in the samples from Ebro an…
Phylogenetic analysis informed by geological history supports multiple, sequential invasions of the Mediterranean Basin by the angiosperm family Arac…
2008
Despite the remarkable species richness of the Mediterranean flora and its well-known geological history, few studies have investigated its temporal and spatial origins. Most importantly, the relative contribution of geological processes and long-distance dispersal to the composition of contemporary Mediterranean biotas remains largely unknown. We used phylogenetic analyses of sequences from six chloroplast DNA markers, Bayesian dating methods, and ancestral area reconstructions, in combination with paleogeographic, paleoclimatic, and ecological evidence, to elucidate the time frame and biogeographic events associated with the diversification of Araceae in the Mediterranean Basin. We focuse…
Recent trends of SST in the Western Mediterranean basins from AVHRR Pathfinder data (1985-2007)
2011
Climate change in the Mediterranean region cannot be understood without taking into account changes in the Mediterranean Sea, which is an important source of moisture and heat for the Mediterranean climate system. Many research papers have been published in the last two decades increasing our knowledge about long-term trends and inter-annual variability of temperature and salinity in the Western Mediterranean. Although recent changes have been better documented, there remain uncertainties because different results are obtained depending on the period of time analyzed or the geographic region selected. This paper analyses the regional, seasonal and decadal variability of sea surface temperat…