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Analysis of seed shape in two subspecies of Capparis spinosa collected in Tunisia: Five populations of Subspecies Spinosa; five populations of Subspecies Rupestris. Morphological description of seeds is a required step for the analysis of biodiversity in natural populations and may give clues to understand adaptive strategies in evolution. The cardioid is the curve described by a point of one circumference rolling around another circumference of equal radius. Models based in the adjustment of seed shape with cardioid curves where described previously for Arabidopsis thaliana and the model legumes Lotus japonicus and Medicago truncatula. In this work the model is applied to the morphology of seeds in populations from two subspecies of Capparis spinosa grown in Tunisia. The adjustment of seed images to cardioid curves, followed by statistical analysis of similarity in the complete images as well as in each of four quadrants, allows an accurate description of seed shape. Results show differences in morphology between subspecies. Seeds from Capparis spinosa. subsp. rupestris present higher diversity in shape than seeds from populations of C. subsp. spinosa. This may indicate a primitive condition in the seeds of C. subsp. rupestris associated with non-specialization. The results are discussed in relation to ecological strategies of both subspecies in evolution.

Ta-MCM41 catalysts have been prepared by grafting of Ta(OEt)5 on MCM41, pre-calcined at three different temperatures (550, 650 and 750 °C). These solids have been modified with two chiral ligands: R-(+)-diethyl l-tartrate (DET) and R-(+)-diisopropyl l-tartrate (DIPT). The formation of the chiral tantalum species and their influence on the structure of MCM41 have been studied by several characterization techniques, such as XRD, FTIR, N2 adsorption isotherms and MAS NMR. The grafted tantalum species are always much less active than the homogeneous analogues in the oxidation of thioanisole (methyl phenyl sulfide) with either aqueous H2O2 or alkyl (tert-butyl, TBHP, or cumyl, CHP) hydroperoxides. The enantioselectivities obtained with the heterogeneous catalysts are also always lower than those obtained with the homogeneous ones under the same conditions, and the best results are obtained with the DIPT-modified solids, up to 25% ee. The calcination temperature of the support and the nature of the oxidant are also parameters that significantly affect the enantioselectivity. The recovered catalysts show an increase in the catalytic activity and a decrease in the enantioselectivity, in agreement with a loss of chiral tartrate, whereas the Si-O-Ta bond remains stable and recoverable.

The thermal decomposition of several metal organic precursors, used in the preparation of YBa2Cu3O7 x superconducting coated conductors (Cu acetate, Cu, Y and Ba trifluoroacetates and Ce propionate) is analyzed by means of several thermoanalytical techniques (TG/DTA, MS and DSC). In all cases, the metal organic precursors deposited as thin films decompose differently than powders from the same precursors. In thin films, decomposition is facilitated by the easier transport of reactive gas from the surrounding atmosphere and by the easier out-diffusion of volatile products. Consequently, films decompose at lower temperature and are more sensitive to the presence of any residual reactive gas in the furnace. Good thermal contact with the substrate is also shown to minimize overheating in films and avoid combustion processes that are otherwise often observed during the thermal decomposition of powders. Finally, the formation and stability of intermediate products towards the oxide formation, such as metal fluorides, differs in films because of the easier gas exchange. With respect to powders, these compounds are much less stable in films, where their decomposition temperature can be lowered by several hundreds of degrees Celsius. While in some cases the behaviour of films can be predicted by analyzing varying masses of precursor powders, this is not always the case. Therefore, thermal analysis carried out on films is recommended to avoid erroneous conclusions about materials preparation drawn from powders.

Salicylic acid (SA) promotes plant defense responses against toxic metal stresses. The present study addressed the hypothesis that 8-h SA pretreatment, would alter membrane lipids in a way that would protect against Cd toxicity. Flax seeds were pre-soaked for 8 h in SA (0, 250 and 1000 µM) and then subjected, at seedling stage, to cadmium (Cd) stress. At 100 µM CdCl2, significant decreases in the percentages of phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and monogalactosyldiacylglycerol (MGDG) and changes in their relative fatty acid composition were observed in Cd-treated roots in comparison with controls. However, in roots of 8-h SA pretreated plantlets, results showed that the amounts of PC and PE were significantly higher as compared to non-pretreated plantlets. Additionally, in both lipid classes, the proportion of linolenic acid (18:3) increased upon the pretreatment with SA. This resulted in a significant increase in the fatty acid unsaturation ratio of the root PC and PE classes. As the exogenous application of SA was found to be protective of flax lipid metabolism, the possible mechanisms of protection against Cd stress in flax roots were discussed.

Soluble lipase from Thermomyces lanuginosa (TLL) was dramatically hyper-activated by a cationic surfactant, cetyltrimethylammonium bromide (CTAB). The greatest hyperactivation (above 340-fold) was observed with 0.005% CTAB. In addition to that, very high hyperactivation was also observed with much higher concentrations of surfactant (100-fold in the presence of 0.3% CTAB). Without surfactant or with very low surfactant concentrations, TLL was not adsorbed to the cationic exchangers. However, in the presence of high concentrations of surfactant (0.3%), the lipase was completely and strongly adsorbed on sulfopropyl-sepharose. The adsorbed enzyme remained hyperactivated (80-fold more active than the soluble enzyme) after elimination of the excess of surfactant. Complete desorption of the hyperactivated TLL from the cationic exchanger is only achieved at 2 M NaCl. The same level of hyperactivation was observed for the hydrolysis of a large substrate: fish oil. The release of EPA (eicosapentaenoic acid) was 80-fold more rapid with hyperactivated TLL derivatives than with TLL very mildly immobilized on CNBr activated agarose. Hyperactivated derivatives were very stable at 25 °C and 37 °C. Full activity was preserved after 1 week.

Cesium sulfate arsenate tellurate (CsSAsTe) presents one reversible phase transition of the first-order type at 213/211 K on heating–cooling runs. Indeed, it crystallizes at T = 120 K in the monoclinic system P21/c and at T = 275 K, in the trigonal system R3c. These crystal structures are built from isolated (HAsO2_4 SO2_4) tetrahedra and (TeO6_6) octahedra, they form tunnels where Cs+ cations and some hydrogen atoms are placed. The cohesion of these structures is assured on the one hand by the interaction between Cs+ and the oxygen atoms and on the other hand, by the presence of hydrogen bonds.

The adsorption/immobilization of Rhizopus oryzae lipase (ROL) has permitted the development of several strategies to improve the properties of this industrial enzyme. The enzyme can be purified, immobilized, hyperactivated and stabilized, though its enantioselectivity could still be improved. A moderately hydrophobic support (e.g., phenyl-Toyopearl) allows the almost-quantitative immobilization of the enzyme via selective hydrophobic adsorption, while any contaminant proteins are not adsorbed. A further desorption of the adsorbed enzyme with surfactants (e.g., 0.5% sucrose laurate) allows the complete purification of the enzyme in only one step, with a 90% purification yield and an 8-fold purification factor. By using a more hydrophobic support, the ROL can be immobilized and hyperactivated. The enzyme is completely adsorbed on octyl-Sepharose and C18-Sepabeads. The pure enzyme (when adsorbed on these supports) becomes hyperactivated to approximately 250% of the activity of the soluble enzyme. In this study, two protocols for the covalent immobilization of ROL were developed: a one-point immobilization on CNBr-activated Sepharose and a multipoint covalent immobilization on highly activated glyoxyl-agarose supports. The multipoint attached enzyme decreased in activity to 50% of the activity of the soluble enzyme, but the derivatives were 300-fold more stable than the soluble enzyme. The hydrolysis of racemic 2-O-butyryl-2-phenylacetic acid was modulated by the different immobilized derivatives. In fact, the most active and selective preparation was demonstrated to be the C18-SB-ROL derivative (0.05 UI/mg and E = 22) when compared with the CNBr-ROL enzyme preparation (0.0073 UI/mg and E = 3.5).

A new compound from the tellurate family was synthesized under a slow evaporation conditions. A crystalline sample of Cs2(HAsO4)0.32(SO4)0.68·Te(OH)6 (CsAsSTe) was calorimetric and spectroscopically characterized. The infrared and Raman spectra of this new compound recorded at room temperature, in the frequency range 500–4,500 and 50–1,500 cm−1, respectively, confirm the presence and the independence of two types of anion HAs/SO4 and TeO6. The thermal analysis of the title compound shows one endothermal and intense peak at 512 K accompanied by a shoulder at 506 K. However, the conductivity evolution versus temperature showed the presence of the protonic super conduction phase transition. The conductivity relaxation parameters of some H+ and Cs+ conducting in the CsAsSTe material have been determined from an analysis of ac conductivity data measured in a wide temperature range. Transport properties in this compound appear due to H+ ions hopping mechanism.

Our success in producing an active epidermal growth factor receptor (EGFR) tyrosine kinase in Escherichia coli encouraged us to express the full-length receptor in the same host. Despite its large size, we were successful at producing the full-length EGFR protein fused to glutathione S-transferase (GST) that was detected by Western blot analysis. Moreover, we obtained a majoritarian truncated GST-EGFR form detectable by gel electrophoresis and Western blot. This truncated protein was purified and confirmed by MALDI-TOF/TOF analysis to belong to the N-terminal extracellular region of the EGFR fused to GST. Northern blot analysis showed two transcripts suggesting the occurrence of a transcriptional arrest.

PESTOLIVE (Contribution of olive history for the management of soil-borne parasites in the Mediterranean Basin) is a project funded by ARIMNet, an ERANET action supported by the 7th European Framework Programme and by non-European Mediterranean countries. PESTOLIVE (www1.montpellier.inra.fr/CBGP/pestolive) aims at producing knowledge and tools for a new and efficient management of plant-parasitic nematodes (PPN) and plant-pathogenic fungi (PPF) in olive (Olea europaea L.) cropping systems and nurseries, while reducing the use of pesticides. Because of the anthropic continuum from Olea post-glacial refuges to oleasters (domestication) and then to olive-trees (breeding and cropping), the fragmentation of the PPN and PPF communities and of their natural enemies could explain the scattered diversity of the control techniques (especially resistance rootstocks, biocontrol, cropping strategies) developed and applied all around the Mediterranean Basin. The novelty of PESTOLIVE is based on i) the analysis and the management of the parasite diversity (ecology of communities) instead of controlling emblematic species (population approach) and ii) the involvement of knowledge about the historical co-adaptation of soil-borne parasite and natural enemies communities to olive-tree domestication (origins and past assemblages) and breeding that follows the history of O. europaea around the Mediterranean Basin.

The aim of this study is to investigate the impacts of exogenous salicylic acid (SA) pretreatments on hydrogen peroxide (H2O2) accumulation, protein oxidation, and H2O2-scavenging enzymes in leaves of Cd-treated flax seedlings. Cdenhanced H2O2 levels were related to increased activities of guaiacol peroxidase (POX, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11), and were independent of changes in catalase (CAT, EC 1.11.1.6) and superoxide dismutase (SOD, EC 1.15.1.1) activities. In control flax seedlings, exogenous SA pretreatments inhibited the activity of CAT, resulted in an enhanced production of H2O2 suggesting that SA requires H2O2 to initiate an oxidative stress. However, although leaves of Cd-free flax seedlings pretreated with SA accumulated in vivo H2O2 by 1.2-fold compared with leaves of Cd-only exposed ones; the damage to growth and proteins after the exposure to Cd was significantly less, indicating that SA can regulate the Cd-induced oxidative stress. Moreover, the Cd-treated seedlings primed with SA exhibited a higher level of total antioxidant capacities and increased activities of H2O2-detoxifying enzymes.

Bm86 midgut protein has been used in order to control ticks of the Hyalomma genus. Previous studies demonstrated the inefficacity of this antigen in the control of Hyalomma scupense, whereas recombinant Hd86 antigen, the Bm86 ortholog in H. scupense produced in Pichia pastoris, was protective against larval H. scupense tick stage infestations but ineffective in the control of the adult stage. One possible explanation for this result is the variation in Hd86 expression levels between these two developmental stages. To test this hypothesis, Hd86 mRNA levels were characterized in H. scupense developmental stages. The expression profile of Hd86 demonstrated a significant variation between tick life stages and showed a significant reduction in the number of transcripts during feeding and, particularly after molting to adults. The most interesting result was noted after molting of engorged nymphs in unfed adults where the expression levels decreased significantly by 12.78 (10.77–17.39) (p < 0.001) and 9.25 (5.77–15.72)-fold (p < 0.001) in unfed males and unfed females, respectively. Comparing unfed nymphs to unfed adult ticks, the Hd86 expression levels decreased by 13.82 (5.39–24.45) (p = 0.035) and 9.93 (2.87–22.08)-fold (p = 0.038) in males and females respectively. Lower Hd86 mRNA levels in adult ticks should result in lower protein levels and thus less antibody–antigen interactions necessary for vaccine efficacy in ticks fed on vaccinated animals. Thus, the observed differences in Hd86 expression profile between immature and adult stages might explain, in part, the discrepancy of the Hd86 vaccine efficacy against these two life stages of H. scupense.

The two-spotted spider mite, Tetranychus urticae Koch, is a worldwide pest that feeds on a large variety of plant families. Because its resistance to acaricides is spreading rapidly, the development of new biological control tactics for population management is crucial. Plant extracts, such as garlic extract (Allium sativum Linn.), may represent viable alternatives, because they are currently considered to be minimum-risk pesticides. Although garlic is known for its acaricidal properties, the extract concentration that provides the most efficient control has not yet been precisely determined. In this study, we conducted a series of laboratory experiments to determine the susceptibility of adult females to different concentrations of garlic extract. Fresh garlic cloves were steam-distilled and sprayed using a Potter spray tower. Mortality and fecundity were measured upon treatment with garlic extract concentrations ranging from 0.46 to 14.4 mg/l. Female mortality increased with concentration, with LD50 and LD90 values of 7.49 and 13.5 mg/l, respectively. Reduced fecundity was previously observed at concentrations of 0.36 and 0.74 mg/l. The chemical composition of the Allium sativum distillate was characterized by reversed-phase high-performance liquid chromatography coupled with photodiode array detection, GC/MS and Fast GC-FID against an authentic standard (Standard, Bioextract).Vinyl dithiin, diallyl disulphide, diallyl trisulphide and methyl allyl trisulphide were identified based on their mass spectra. Sesquiterpenoids were identified by their retention index.

Uncertainty in hydrological model prediction stems from different sources such as parameter uncertainty, errors of input data, model structure uncertainty, lack of knowledge about the physical characteristics of the watershed and uncertainty in discharge data used to calibrate the model. Portioning and quantifying all these uncertainty sources that affect models and predictions is a difficult and challenging task due to the possible correlation of model parameters, to the propagation and correlation of the errors, to the model complexity, etc. Parameter uncertainty is usually considered as the main source of the model prediction uncertainty while discharge data uncertainty is rarely taken into account when calibrating the model. In this work a new calibration technique of the SWAT model is developed to account explicitly for the uncertainty in discharge data caused by uncertainty in the rating curve. For a given discharge value, a probability distribution function of true discharge was estimated from the constructed uncertain rating curves. This method was applied in three automatic calibration techniques SUFI2, GLUE and ParaSol to calibrate the SWAT model in two Mediterranean watersheds (Vène and Pallas). The uncertainty prediction confidence interval (95PPU) of each of the applied techniques was more successful at bracketing the measured data when uncertainty in the rating curve is accounted for. Discharge uncertainty contributed to total model uncertainty by 8 to 27 % (with an average value of 13 %) for the Vène watershed and by 3 to 20% (with an average value of 9 %) which shows that uncertainty in discharge measurement is not a negligible uncertainty source and has to be considered in hydrological modeling for more accurate model prediction that can be used in decision making for developing sustainable water resource management strategies.

Wastewaters produced by industry and municipalities contain numerous synthetic compounds in varying concentrations. Micro pollutants can be defined as inorganic and organic substances present at low concentrations (pg/L to ng/L) in the environment having adverse consequences for living organisms at these low concentrations. To date, an effective and sustainable global strategy against this insidious contamination of aquatic environments barely exists. Source controls and technical systems, such as wastewater treatment plants, function only as partial barriers or not at all. In this presentation, we present an efficient strain of white rot fungi producing high amounts laccase capable of transforming the tested micro pollutants (bisphenol A, nonylphenols and triclosan). The enzymes are successfully immobilized on mesoporous silica particles to form a biocatalyst. Successful and promising tests were realized with this biocatalyst in various reactors designed for the micro pollutants abatement process., info:eu-repo/semantics/nonPublished

The dietary fibers (DF) of 10 date varieties from Tunisian oases have been investigated. Further knowledge on the content, composition, and technological applications of those fibers could support their genetic variability and promote the socioeconomical development of growing areas. The composition, water- and oil-holding capacities, solubility, and antiradical activity have been determined. The DF content ranged from 4.7% (Matteta, Rochdi) to >7% (Deglé Nour, Garen Gaze, Smeti). Composition varied significantly among cultivars, and the results evidenced that uronic acids and lignin determine to a great extent the organoleptic quality of dates. Many of the varieties that have been studied (Garen Gaze, Matteta, Kenta, Rochdi, Mermella, Korkobbi, Eguwa) were selected because of great interest from technological and functional points of view. Among their physicochemical characteristics, these samples presented water- and oil-holding capacities of higher than 17 and 4 mL/g fiber, respectively, which make them suitable for use as additives in fiber-enriched foods. Also, DF of Garen Gaze, Smeti, Mermella, and Eguwa had a high antiradical capacity (>230 Trolox equiv/kg fiber). It was concluded that some of these varieties could be grown as potential sources of DF, which could be included in the formulation of fiber- and antioxidant-enriched foods. © 2012 American Chemical Society.

The genus Hyalomma includes the most frequent tick species infesting livestock in North Africa, one of these species, Hyalomma scupense (syn. H. detritum) is particularly important due to its role in the transmission of tropical theileriosis to cattle (Theileria annulata infection). We have cloned and characterized the orthologs of the Bm86 gene from H. scupense strains collected over Tunisia in 2006 and 2009. The recombinant protein rHd86 was expressed in Pichia pastoris for vaccination purpose using a transcript from the 2006 strain. The rHd86 was then purified from the yeast culture supernatant by a filtration and a size exclusion process. It was recognized by specific anti-Bm86 antisera. An important extent of inter-specific diversity ranging from 35 to 40% was recorded between Hd86 and Bm86/Bm95 proteins whilst a very limited level of intra-specific diversity (1.7%) occurred between the Hd86 vaccine candidate protein and its homologues from H. scupense strains collected in 2009. These results emphasise the need for assessing the efficacy against H. scupense and others important cattle Hyalomma species in Tunisia of our Hd86 vaccine candidate alongside with a Bm86 vaccine.

The Rhipicephalus microplus recombinant Bm86-based tick vaccines have shown their efficacy for the control of several Hyalomma cattle ticks genera, namely H. dromedarii and H. anatolicum. However, H. scupense species, the most important tick in North Africa has never been studied. Vaccination trials using either a recombinant Bm86-based vaccine or a recombinant Hd86-based vaccine (the Bm86 ortholog in H. scupense) were conducted in cattle against immature and adult H. scupense ticks and adult H. excavatum ticks. The results showed a 59.19% reduction in the number of scupense nymphs engorging on Hd86 vaccinated cattle. However, cattle vaccination with Bm86 or Hd86 did not have an effect on H. scupense or H. excavatum adult ticks infestations. These results showed that Hd86 vaccines are selectively effective against H. scupense immature instars and emphasize on an integrated anti-tick vaccine control in North Africa.

The ixodid ticks from the Hyalomma genus are important pests of livestock, having major medical and veterinary significance in Northern Africa. Beside their direct pathogenic effects, these species are vectors of important diseases of livestock and in some instances of zoonoses. Anti-tick vaccines developed in Australia and Cuba based on the concealed antigen Bm86 have variable efficacy against H. anatolicum and H. dromedarii. This variation in vaccine efficacy could be explained by the variability in protein sequence between the recombinant Bm86 vaccine and Bm86 orthologs expressed in different Hyalomma species. Bm86 orthologs from three Hyalomma tick species were amplified in two overlapping fragments and sequenced. The rate of identity of the amino acid sequence of Hm86, He86 and Hdr86, the orthologs of Bm86, respectively, in H. marginatum marginatum, H. excavatum and H. dromedarii, with the Bm86 proteins from Rhipicephalus microplus (Australia, Argentina and Mozambique) ranged between 60 and 66%. The obtained amino-acid sequences of Hmm86, He86 and Hdr86 were compared with the Hd86-A1 sequence from H. scupense used as an experimental vaccine. The results showed an identity of 91, 88 and 87% for Hmm86, He86 and Hdr86, respectively. A specific program has been used to predict B cells epitopes sites. The comparison of antigenic sites between Hd86-A1 and Hm86/Hdr86/He86 revealed a diversity affecting 4, 8 and 12 antigenic peptides out of a total of 28 antigenic peptides, respectively. When the Bm86 orthologs amplification protocol adopted in this study was applied to H. excavatum, two alleles named He86p2a1 and He86p2a2 were detected in this species. This is the first time that two different alleles of Bm86 gene are recorded in the same tick specimen. He86p2a1 and He86p2a2 showed an amino acid identity of 92%. When He86p2a1 and He86p2a2 were compared to the corresponding sequence of Hd86-A1 protein, an identity of 86.4 and 91.0% was recorded, respectively. When comp

A comparison among different advanced extraction techniques such as microwave-assisted extraction (MAE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE), together with traditional solid-liquid extraction, was performed to test their efficiency towards the extraction of phenolic compounds from leaves of six Tunisian olive varieties. Extractions were carried out at the best selected conditions for each technique; the obtained extracts were chemically characterized using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS 2). As expected, higher extraction yields were obtained for PLE while phenolic profiles were mainly influenced by the solvent used as optimum in the different extraction methods. A larger number of phenolic compounds, mostly of a polar character, were found in the extracts obtained by using MAE. Best extraction yields do not correlate with highest cytotoxic activity against breast cancer cells, indicating that cytotoxicity is highly dependent on the presence of certain compounds in the extracts, although not exclusively on a single compound. Therefore, a multifactorial behavior is proposed for the anticancer activity of olive leaf compounds. © 2012 Elsevier Ltd.

In the present work, a simple and rapid method for the extraction of phenolic compounds from olive leaves, using microwave-assisted extraction (MAE) technique, has been developed. The experimental variables that affect the MAE process, such as the solvent type and composition, microwave temperature, and extraction time, were optimized using a univariate method. The obtained extracts were analyzed by using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS 2) to prove the MAE extraction efficiency. The optimal MAE conditions were methanol:water (80:20, v/v) as extracting solvent, at a temperature equal to 80 °C for 6 min. Under these conditions, several phenolic compounds could be characterized by HPLC-ESI-MS/MS 2. As compared to the conventional method, MAE can be used as an alternative extraction method for the characterization of phenolic compounds from olive leaves due to its efficiency and speed. © 2011 American Chemical Society.

The essential oil of Deverra scoparia Coss. & Durieu was investigated for its acaricidal activity against the worldwide pest twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). The essential oil was analyzed by fast gas chromatography (GC) and GC-mass spectrometry. The activities of its individual and blended constituents were determined. Our study showed that female mortality increased with increasing D. scoparia oil concentrations, with LD50 and LD90 values at 1.79 and 3.2 mg liter1, respectively. A reduction in fecundity had already been observed for concentrations of 0.064, 0.08, and 0.26 mg liter1 D. scoparia essential oil. Ten major components,comprising 98.52% of the total weight, were identiÞed; -pinene was the most abundant constituent (31.95%) followed by sabinene (17.24%) and 3-carene (16.85%). The 10 major constituents of D.scoparia oil were individually tested against T. urticae females. The most potent toxicity was found with -pinene, 3-carene, and terpinen-4-ol. The presence of all constituents together in the artiÞcial mixture caused a signiÞcant decrease in the number of eggs laid by females, at 0.26mgliter1 (11 eggs),compared with the control (50 eggs). The toxicity of blends of selected constituents indicated that the presence of all constituents was necessary to reproduce the toxicity level of the natural oil.

Physically based watershed models are increasingly being used to support decisions about alternative management strategies in the areas of land use change, climate change, water allocation, and pollution control. Therefore, the ability of these hydrological models to reproduce the physical process of the watershed must be carefully evaluated, as well as the uncertainty in modeling predictions. We evaluate in this study the capability of the SWAT (Soil and Water Assessment Tools, Arnold et al., 2000) model in reproducing the hydrology of two small Mediterranean watersheds through sensitivity, calibration and uncertainty analysis. The objective is to compare different calibration techniques for assessing model performance and modeling uncertainty.

Recent excavations at Althiburos, northern Tunisia, have shown the existence of permanent pre-roman occupations in the central area of the urban settlement. Significantly, the site has been found to contain one of the most complete Numidian sequences, spanning from the Early Numidian (at least from the 10th–9th century BC) to its final stage. Research at the site addresses questions related to the identification of settlement patterns at this time. The combined study of phytoliths and spherulites recovered from well defined archeological contexts at the site have provided new data for identifying husbandry activities carried out by the ancient Numidian populations. The results show that there is abundant evidence for both cooking and processing cereals, primarily from common or bread wheat (Triticum aestivum). Also significantly, was the abundance of faecal spherulites in certain areas of the site, indicative of dung accumulation. The correlation between large amounts of spherulites and rich phytolith sediments in specific contexts, suggested that grasses were brought to the site or consumed offsite and deposited onsite as livestock dung or dung-products. The identification of dung accumulations in the site raises questions about the diversity of economic practices developed by Protohistoric communities in northern Africa. Future research questions regarding such dung rich layers will also be examined.

The use of olive mill wastewater (OMW) by agricultural spreading constitutes an alternative among the solutions proposed. The experiment was carried out in Sidi Bou Ali (Tunisia), with three treatments, T0, T1 (25 m3/ha) and T2 (50 m3/ha) during four months. By means the physical capillary model for porous media, pF curves were established and the effects of OMW on the soil physical characteristics were studied. It was concluded that the OMW, for the two applied doses, induced a decrease in water retention for all tensions. An increase in saturated state hydraulic conductivity was obtained in a more pronounced manner in the case of topsoil for all dates. These results confirm the migration process of OMW from the topsoil to the underlying horizon. Such soil modifications are already required in order to establish a mulch on the soil surface so as to reduce the evaporation water losses., L'applicazione agricola di acque reflue dei frantoi oleari (ARO) è un'alternativa tra le opzioni per migliorarla. L'esperimento è stato effettuato a Sidi Bou Ali (Tunisia), con tre trattamenti, T0, T1 (25 m3/ha) e T2 (50 m3/ha) per quattro mesi. Attraverso il modello fisico capillare del mezzo poroso, le curve pF sono state stabilite e gli effetti delle ARO sulle caratteristiche fisiche del suolo sono stati studiati. Si è concluso che le ARO hanno indotto una riduzione della la ritenzione idrica per tutte le tensioni più marcate. Un aumento di conduttività idraulica satura è stato ottenuto in modo più pronunciato nel caso dello strato superficiale per tutte le concentrazioni. Questi risultati confermano il processo di migrazione di ARO dal topsoil all'orizzonte sottostante. Tali modifiche del suolo sono già tenute al fine di stabilire un pacciame sulla superficie del suolo per ridurre le perdite di evaporazione dell'acqua.

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IIIe Congrès International: Association Internationale pour la Formation, la Recherche et l'Intervention Sociale (AIFRIS), info:eu-repo/semantics/nonPublished

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Colloque organisé par l’Université de Tunis en partenariat avec l’Université d’Anvers, info:eu-repo/semantics/nonPublished

In this chapter we analyze natural resource use and the challenges for conservation in cork oak woodlands, in the context of the developing economy of Tunisia. For this purpose, cork oak woodland area includes associated shrubland (hereafter woodland). Our analysis focus only on total income supplied by cork oak woodland activities, although we refer also to livestock rearing and crop activities, which are the other two activities in agroforestry.

The lack of natural regeneration and the depletion of cork oak trees have stressed the interest in cork oak forests conservation in Cádiz (Spain) and Ain Snoussi (Tunisia). The mature cork oak forests face the aging of their cork oaks. However, this has not encouraged landowners to renewing the Cadiz and the Ain Snoussi cork oak forest by natural regeneration. Two management scenarios have been simulated, under the first one, the cork oak would naturally regenerate at infinite horizon, whilst by the second one, no regeneration treatments are presumed which lead the cork oak trees to age until they eventually disappear and cork oak forest is replaced by an un-wooded shrubland. The objective of this paper is to compare the economic results of sustainable natural regeneration and unsustainable management of the Cadiz and Ain Snoussi cork oak forests. For this purpose, a cost-benefit analysis was conducted indicating expenditures and revenues of the whole production life cycles of cork oak forests under the two management scenarios. A group of physical and economic indicators that arrive at a steady state cork oak forest management are also measured. The market results show that sustainable cork tree management in Ain Snoussi has a higher discounted total income and a lower capital income at infinite horizon using a real discount rate equal or higher than 2 %, compared to the current cork oak depletion scenario. Whilst, in Cadiz cork oak forest renewing leads to important capital losses under current cork prices and government aids, using real market discounting rates equal or higher than 4%. In Ain Snoussi the total income distribution, under steady state conditions, shows that sustainable management is more profitable for the landowner (Tunisian State), and less advantageous for families self-employed workers. In Cadiz mature cork oak forest that would have ongoing natural regeneration of its cork oaks offers competitive capital incomes if compared with an un-wooded s

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