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The study analysed the driving forces of the desertification processes and evaluated the results of a revegetation planning in an internal region of Morocco.

We evaluated the long-term outcome of oxcarbazepine (OXC) monotherapy in a population of patients switched over from carbamazepine (CBZ) monotherapy. Subjects of the study were recruited among patients who had successfully completed the PRIMO study, a recent multicentre Italian study that assessed the therapeutic equivalence of immediate (overnight) and more progressive switching from CBZ to OXC monotherapy in patients with partial seizures unsatisfactorily maintained on CBZ monotherapy due to poor tolerability or scant clinical efficacy. Treatment retention rate was chosen as a composite parameter for both efficacy and tolerance of OXC. Twelve months after having completed the PRIMO study, 91 of 105 patients (87%) were still taking OXC, 80 of them (76%) as monotherapy. Mean OXC dose was 1250+/-459 mg/day. Eighty-four out of 105 patients (80%) rated OXC tolerability as "good" or "very good". The mean ratio of the last dose of OXC to the last dose of CBZ increased from 1.54 (end of PRIMO study) to 1.69 (end of follow-up). The large majority of a population of patients who were successfully switched from CBZ monotherapy to OXC monotherapy maintained OXC treatment for at least a further 12 months. The 1.5 OXC/CBZ ratio appears to be close to the optimal for the switch from CBZ to OXC, at least in patients treated with CBZ monotherapy.

A multidisciplinary approach was followed to study the pedogenic and palaeoclimatic information preserved in a buried palaeosol belonging to a Late Quaternary succession located along the bay of Alghero (north-western Sardinia). The bay is dominated by a 5-km long sandy beach-ridge system backing an N-S oriented lagoon system (Calich). The succession studied is characterized by basal shallow marine deposits, followed by clayey lagoon sediments and colluvial strata and capped by a relatively thick aeolianite. The research was based on pedological and sedimentological analyses, supported by optically stimulated luminescence (OSL) dating and by an in-depth micro-morphological study. Three main climatic pulses were highlighted during the Eemian. A wet period, with intense carbonate leaching occurred at the very beginning of the Eemian interglacial followed by very dry climatic conditions. This dry phase was long and arid enough to allow the formation of a thick calcrete hardpan, a typical feature of semi-arid environments. The hardpan is dated at about 120 ka (kilo annum) and this dry event is tentatively associated with the late Eemian arid pulse (LEAP). The last phase of the Eemian recorded the restoration of a wetter climate. Finally, the succession indicated that even in a cooler environment, the central Mediterranean most probably maintained temperate conditions at least until the end of the MIS 5c (about 95 ka; early Würm). © 2014 British Society of Soil Science.

This contribution summarizes the main activities carried out in two Erasmus Intensive Programmes involving five Universities from France, Hungary, Greece, Italy, Portugal, and Spain for six years. In each year a group of 25 students and 6 teachers participate for 15 days in different interactive teaching activities related to soil conservation. Different issues were taught and discussed in international collaboration. The main outputs of this collaboration teaching were interactive exercises and two handbooks. info:eu-repo/semantics/publishedVersion

A multi-disciplinary approach was followed to investigate two thick palaeosol strata that alternate with wind-blown dominated deposits developed along the Alghero coast (North-west Sardinia, Italy). Optically stimulated luminescence ages reveal that both palaeosols were developed during cooler drier periods: the first one at around 70ka Marine Isotope Stage 4 and the latter around 50ka (Marine Isotope Stage 3). In contrast, the pedological features indicate that the palaeosols underwent heavy weathering processes under warm humid to sub-humid conditions, characteristic of the Sardinian climate during the last interglacial stage (Marine Isotope Stage 5e). To reconcile this apparent data discrepancy, a range of sedimentological and pedological analyses were conducted. These analyses reveal that the palaeosols possess a complex history, with accumulation and weathering occurring during Marine Isotope Stage 5e, and erosion, colluviation and final deposition taking place during the following cold stages. Thus, even if these reddish palaeosols were last formed during the glacial period, the sediments building up these strata probably record the climate of the last interglacial stage (Marine Isotope Stage 5e). Trace element and X-ray diffraction analyses, together with scanning electron microscope images, reveal the presence of Saharan dust in the parent material of the palaeosols. However, no evidence of any far-travelled African dust has been observed in the Marine Isotope Stage 4-3 aeolian deposits. It is possible to conclude that in the West Mediterranean islands, Saharan dust input, even if of modest magnitude, is preserved preferentially in soils accumulated and weathered during interglacial stages. © 2011 The Authors. Journal compilation © 2011 International Association of Sedimentologists.

Articolo numero ITR/P1-10

The Tokamak á Configuration Variable, TCV, is equipped with a moveable ECE receiving antenna, identical to the 6 second harmonic (X2) ECH/ECCD launchers, which can track the plasma at any position within the vacuum vessel in real time. In contrast to this poloidal plane viewing, the receiver can be rotated to obtain an oblique view. In this configuration, measurements of the asymmetry of the electron distribution function, EDF, are performed during co/counter ECCD sweeps at constant input power. Direct evidence of the driven current is provided by the ratio of radiation temperatures from co and counter views of identical plasmas. The results are simulated by the NOTEC/TCV radiation-transfer code in which current profile broadening can be included to reproduce the measurements. Studies of core broadband temperature uctuations, induced by plasma turbulence, are performed with a high-resolution X2 correlation ECE diagnostic. ECE correlation is measured by two frequency-tunable YIG filters that can be placed between r/a = 0 - 0.9 using both their wide tuning range, and plasma geometry changes from shot to shot. Evidence of broadband (20{150 kHz) uctuations with peak frequencies ranging from 20 kHz up to 90 KHz at r/a = 0.3 - 0.8 in Ohmic sawtooth-free discharges was obtained. The amplitude of the temperature uctuations decreases with increasing density and thus, increasing collisionality, which is in qualitative agreement with predictions from quasi-linear gyrokinetic calculations performed with the gyrokinetic code GS2. The mixing length heat diffusivity calculated from GS2 decreases with increasing collisionality, as does that obtained from a power balance analysis. The real frequency of the broadband turbulence stays positive over the range of collisionalities explored, indicating dominant TEM turbulence.

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Nel presente lavoro è stata testata una metodologia sperimentale per lo studio dei processi erosivi conseguenti alle pratiche agronomiche utilizzate per la gestione dei pascoli. La ricerca è stata condotta in un'area della Sardegna centro orientale, in territorio di Irgoli (Nuoro). Al fine di stimare i flussi di suolo lungo un versante è stata adottata una procedura basata sulla misura delle variazioni altitudinali della superficie del suolo lungo coppie di transetti. È stata inoltre effettuata un'analisi dell'erosività delle precipitazioni.

In Sardinia (Italy) agropastoral activities constitute an important factor of pressure on fragile soil resources. The Mediterranean type climate, characterised by irregular and intense rainfall, coupled with mountain and hill landscapes dominated by shallow soils, makes the region vulnerable to soil erosion and desertification. These processes are particularly accelerated by agropastoral activities, especially in some areas where social and economic drivers induce the farmers to clear natural vegetation cover or to intensify cropping or forage production and grazing on steep slopes. In these cases, severe soil loss (due to both water and tillage erosion) and degradation occur. The present work is the result of a long lasting research, focused on understanding and assessment of soil degradation, by adopting an interdisciplinary approach. The impacts of land use on soil properties were studied in an area located in the centraleastern part of the Island, irrationally ploughed and overgrazed. Sampling sites were selected in relation to land cover, land suitability and land use change patterns, in order to assess situations characterised by different degrees of pressure (intensity and time) and to compare degraded and pristine soils. Different kinds of soil degradation indicators were tested: physical (soil granulometry, soil density and resistance to surface penetration), chemical (routine set), biological (QBS, a soil quality index based on micro-invertebrate fauna), micromorphological (microporosity, quantified from thin sections through image processing software). The results show that during the last 15/20 years land use markedly influenced soil properties in most of the surveyed sites. In particular, apart from the heavy soil loss observed, soil organic carbon, soil density and porosity were significantly affected, showing the unsustainability of current agropastoral activities. The work also contributed to build up a set of methods and indicators to monitor soil degradation in comparable Mediterranean rural contexts.

The objective of the paper was to assess spatial uncertainty of a soil erodibility factor (K) model resul from the uncertainties in the input parameters (texture and organic matter). The 500 km2 study area was located in central-east Sardinia (Italy) and 152 samples were collected according to pedological horizons. A MonteCarlo analysis was performed incorporating spatial cross-correlation info through joint turning bands simulation was incorporated. A linear coregionalization model was fitted to all direct and cross-variograms of the input variables, which included 3 different structures: a nugget effect, a spherical structure with a shorter range (3500 m) and a spherical structure with a longer range (10000 m). The K factor was then estimated for each set of 500 joint realizations of the input variables, and the ensemble of the model outputs was used to infer the soil erodibility probability distribution function. This approach permits delineation of areas characterised by greater uncertainty, to improve supplementary sampling strategies and K value predictions.

The ITER ECW system consists of up to 24, 170 GHz gyrotrons, 1 to 2 MW each, connected to one launcher situated in one equatorial port (EL) and four launchers in the upper ports (UL), for a nominal injected power of 20MW. The two launchers systems, designed to inject mm-waves at various locations in the plasma, have different current drive characteristics: beams launched from the EL, having toroidal steering, give broad jCD profiles and higher total driven current, good for central deposition and current profile control, while the UL, where the beams are steered in the poloidal direction, gives narrow jCD profiles, good control of MHD activity such as NTM and sawteeth. Up to the end of 2005 the main goal of the physics analysis has been to evaluate the performance of the UL both in terms of the required steering range and of the figure of merit for Neoclassical Tearing Modes (NTMs) stabilization (?NTM=JCD/Jbs), for (2,1) and (3,2) modes for three reference ITER scenarios and for two launcher designs, the Front Steering (FS) and the Remote Steering (RS). Since the FS offers appreciable reserve in ?NTM, a new variant of the UL has been designed that improves the capabilities of the system with respect to sawteeth stabilization, by adopting different deposition ranges for upper and lower mirrors while still maintaining acceptable ?NTM over the full range. A possible synergy between the UL and EL has been pointed out, with the ultimate goal of providing an enhanced physics program in ITER. In this work it is shown that, by adding to present design of the EL the possibility to drive counter-current in addition to the existing co-current capability as well as modifying the poloidal tilt angle for the top and bottom steering mirrors, the flexibility of the system is increased and heating and current drive may be decoupled, increasing the capability for the control of the discharge and enhancing the operational domain. The possibility to avoid sawteeth by raising the q profile above q=1 in a variant of Scenario 2 and the large flexibility in controlling q0 in the advanced Scenario 4 are shown. For the UL, the performance for NTM and sawteeth control by injecting the R.F. beams from a lower location are compared with that achieved with the present port location, both at nominal and at reduced magnetic field. *) This work has been carried out under EFDA Technology Task TW6-TPHE-ECHULA

Using a new LFS receiving antenna in the oblique ECE configuration, we measure the emission during central co-ECCD and counter-ECCD discharges. The asymmetry of the electron distribution function (EDF) resulting from ECCD is put into evidence by performing 4 successive discharges measuring quasi-X mode and quasi-O mode in 2 separate discharges; then, repeating these measurements while viewing in the opposite toroidal direction. The plasma configuration and EC injection are identical in the 4 cases. The ratios of the X-mode signals are compared to simulations of the ECE by the NOTECTCV code and are found to be generally consistent with emission from a small, drifting, suprathermal, electron population carrying the ECCD current of the order calculated by the TORAY-GA code.

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The purpose of the ITER electron cyclotron resonance heating (ECRH) upper port launcher is to stabilize the neoclassical tearing mode (NTM) by driving currents (co-ECCD) locally inside either the q=3/2 or 2 island1. A narrow current deposition profile along with a wide steering range is required to deposit current inside all islands forming at relevant flux surfaces over the wide spectra of possible ITER plasma equilibria. The ITER launcher reference design uses a front steering (FS) mirror that provides optimum focusing for NTM stabilisation and the possibility for a wide steering range. A two-mirror system (focusing and steering) decouples the steering and focusing functions of the launcher for enhanced performance2 over that of a remote steering concept. The steering mechanism uses a frictionless system3, flexure pivots replace traditional bearings and a gas pneumatic actuator replaces mechanical feeds. Two FS launcher designs are under consideration: an NTM launcher providing access over the region in which the NTMs are expected to occur (0.64

Neoclassical tearing modes (NTMs) are magnetic islands which increase locally the radial transport and therefore degrade the plasma performance. They are self-sustained by the bootstrap current perturbed by the enhanced radial transport. The confinement degradation is proportional to the island width and to the position of the resonant surface. The q=2 NTMs are much more detrimental to the confinement than the 3/2 modes due to their larger radii. NTMs are metastable in typical scenarios with ?N>1 and in the region where the safety factor is increasing with radius. This is due to the fact that the local pressure gradient is sufficient to self-sustain an existing magnetic island. The main questions for burning plasmas are whether there is a trigger mechanism which will destabilize NTMs, and what is the best strategy to control/avoid the modes. The latter has to take into account the main aim which is to maximize the Q factor, but also the controllability of the scenario. In this paper we present different aspects of the above questions, in particular the role of partial stabilization of NTMs, the possibility to control NTMs at small size with little electron cyclotron heating (ECH) power and the differences between controlling NTMs at the resonant surface or controlling the main trigger source, that is the sawteeth.

Sardinia (Italy) is an island representative of Mediterranean rural areas, where agropastoralism is the main economic activity, with more than 80% of the total area used for agriculture. Intense agropastoral activities, particularly tillages and other activities realised with heavy machinery, are causing severe soil erosion and compromising agricultural productivity. Soil physical and chemical properties have been altered by erosion, such as the fertile topsoil has been lost and soil productivity has been reduced by erosion processes. The study area is located in central-eastern Sardinia. The climate is dry sub-humid, with a mean annual temperature of about 17 °C and mean annual precipitation ranging from 500 to 700 mm, with an autumn maximum, a season which also is characterised by storms and high rainfall intensities. The objective of this work is to assess the impacts of land use on soil characteristics in an agropastoral area. Sampling sites were selected in relation to land use suitability and land use history and with particular reference to the intensity and frequency of agronomical practices such as tillages and mechanical shrub removal. Soil profiles were described in 14 plots; furthermore, a total of 42 soil samples (3 sampling point in each plot) were collected. Physical and chemical soil properties were analysed. The results were treated statistically. The results show differences in physical and chemical properties of soils in relation to land use. The land use influences markedly all physical and chemical soil properties analysed in this study and caused severe soil degradation in most of the situations analysed.

The purpose of the ITER electron cyclotron resonance heating (ECRH) upper port launcher is to stabilize the neoclassical tearing mode (NTM) by driving currents (co-ECCD) locally inside either the q=3/2 or 2 island1. A narrow current deposition profile along with a wide steering range is required to deposit current inside all islands forming at relevant flux surfaces over the wide spectra of possible ITER plasma equilibria. The ITER launcher reference design uses a front steering (FS) mirror that provides optimum focusing for NTM stabilisation and the possibility for a wide steering range. A two-mirror system (focusing and steering) decouples the steering and focusing functions of the launcher for enhanced performance2 over that of a remote steering concept. The steering mechanism uses a frictionless system3, flexure pivots replace traditional bearings and a gas pneumatic actuator replaces mechanical feeds. Two FS launcher designs are under consideration: an NTM launcher providing access over the region in which the NTMs are expected to occur (0.64

In Sardinia, a Mediterranean island, desertification is mainly related to the shift from traditional to more intensive agricultural systems. The over-exploitation of existing pastures and the creation of new pastures on unsuitable land induces an increase of the degradation of natural and environmental resources. The impact of such agropastoral production systems on the environment is analysed by considering a specific case study in Sardinia. The aim of the present work is to present the experimental activities carried out in order to characterize the soil erosion processes due to this kind of land use. A simplified experimental methodology was set up to study the dynamics of the channelled erosion process (rill erosion) by monitoring temporal evolution of soil roughness along the slope. The experimental plot is located on a steep slope in a hilly area of Central Eastern Sardinia, where intense agropastoral activities, particularly tillages, realised with heavy machinery, are causing severe soil erosion and compromising agricultural productivity. The adopted procedure is based on the recording of altitudinal variations of soil surface along two couples of transects parallel to the contour lines. Measurement were carried out from October 2001 to December 2004. Meteorological parameters were recorded by a meteorological station located near the plots; rainfall erosivity and kinetic energy were calculated. Statistical and fractal techniques were used to quantify surface roughness. The total soil loss was also estimated, by referring to the temporal variation of the average value of the surface level along each transect.

In Sardinia, a Mediterranean island, desertification is mainly related to the shift from traditional to more intensive agricultural systems. The over-exploitation of existing pastures and the creation of new pastures on unsuitable land induces an increase of the degradation of natural and environmental resources. The impact of such agropastoral production systems on the environment is analysed by considering a specific case study in Sardinia. The aim of the present work is to present the experimental activities carried out in order to characterize the soil erosion processes due to this kind of land use. A simplified experimental methodology was set up to study the dynamics of the channelled erosion process (rill erosion) by monitoring temporal evolution of soil roughness along the slope. The experimental plot is located on a steep slope in a hilly area of Central Eastern Sardinia, where intense agropastoral activities, particularly tillages, realised with heavy machinery, are causing severe soil erosion and compromising agricultural productivity. The adopted procedure is based on the recording of altitudinal variations of soil surface along two couples of transects parallel to the contour lines. Measurement were carried out from October 2001 to December 2004. Meteorological parameters were recorded by a meteorological station located near the plots; rainfall erosivity and kinetic energy were calculated. Statistical and fractal techniques were used to quantify surface roughness. The total soil loss was also estimated, by referring to the temporal variation of the average value of the surface level along each transect.

According to the United Nations Convention to Combat Desertification soil erosion is one of the main causes of desertification in the northern Mediterranean. Recently the role of channel erosion in sediment delivery has become better understood by experimental research. The aim of the present work is to set up a simplified experimental methodology to study the relations between gully erosion, land types, and land use. The experimental area (about 720 ha) is located in a hilly region threatened by desertification in central eastern Sardinia, Italy, and is characterised by uneven morphology with steep slopes, where agropastoral activities, particularly tillage with heavy machinery and overgrazing,are causing severe soil erosion and compromising agricultural productivity. Previous studies carried out in the same area highlighted the need to quantify and monitor soil erosion to be able to give management guidelines to decision makers and to farmers. In this study, carried out in May 2003, an inventory of gullies of the area was made through an integrated use of aerial photographs and field surveys. The degree of activity and morphological features of gullies were assessed in the field using simple criteria. The approach applied included the measurement of the position and shape of gully heads and their width and depth at specific points. Relations were studied among distribution, frequency, and morphological characteristics of gullies and geomorphological features and land use.

Soil degradation is referred to as the reduction of the biological or economical productivity of the soils, due to processes including erosion, change of physical or chemical state (acidification, compaction, salinization) and loss of nutrient or organic matter. Although climatic factors often contribute to cause it, soil degradation is generally related to human activities as deforestation, agricultural intensification and urban expansion. This is the case for the Mediterranean regions of Europe, where erosion processes are particularly severe. Assessment and mapping of erosion risk can be a useful tool for mitigating these phenomena. That can be done by individuating specifical indicators and defining an operative methodology for appropriately weighting and combining them. We have developed a new approach based on multivariate geostatistics and GIS that allows taking into consideration in a flexible way a potentially unlimited number of indicators. This method transforms measured data values into a binary value according to specific criteria. The criteria, developed independently for each indicator, are critical values or ranges of values representing the condition in which the single indicators determine a significant degree of risk. These criteria have to be calibrated locally. Each soil indicator is then mapped as the probability that an area is subjected to the risk of erosion. To interpolate these information, we have utilised an approach based on non parametric geostatistics called indicator kriging. We have then applied factor kriging to define two synthetic weighted indexes summarising the effects of several variables on soil erosion. We present here an example of application to a study area in Sardinia (Italy), which is considered representative of Mediterranean zones at high erosion risk. We selected six variables affecting soil erosion: arable soil depth, organic matter, slope, a texture index, drainage class and land use. We produced maps of both individual soil indicators and synthetic indexes. This procedure allows the identification of both the areas at high erosion risk and the single indicator parameters that cause risk in those zones, thus allowing specific management plans or land use policies to be developed.