Analysis of the farmer's behaviors and the risk of exposure to the vector of Zoonotic cutaneous leishmaniasis in Tunisia

The research shows that behaviour of farmers in relation to irrigation is imposed by the nature of the agricultural activity, by the hydraulic system, and by the method of irrigation. A mathematical model is used to calculate risk of exposure to Zoonotic Cutaneous Leishmaniasis (ZCL). Farmers in the El Hichria (Tunisia) irrigated perimeter (IP) use water distributed by surface canals. In the Ouled Mhamed IP, underground pressurized water pipes bring water to irrigation terminals. The farmers are exposed to the risk of contact with the Phlebotomus papatasi, a vector of ZCL, of 0.25 on a scale of 1, associated with irrigation

Olive growing in arid area: further challenges from climate change

In Tunisia, agriculture is vulnerable to climate change with harmful impacts subsequent warming and drying trends. In these regions, olive industry plays a key role at regional and national level. Therefore, the identification of adapted olive tree genotypes has become an urgent need to develop sustainable agriculture in arid lands. This study aimed to evaluate the impact of climatic variation on the olive growing systems in arid and sub-arid areas of Tunisia. The phenological behavior of Chemlali and Zalmati, main olive cultivars wide spreading in central and southern Tunisia, respectively, were considered to evaluate their capacity to adapt to contrasting climatic conditions. Over the 2005-2019 period, olive cultivars presented variable flowering dates related to local climatic conditions. Zalmati cultivar bloom in Zarzis seems to be earlier than Chemlali cultivar in Sfax region with average flowering dates of DOY-92 (April-3) and DOY-106 (April-17), respectively. A tendency for advancing the growing season was observed with warmer winters, which leads to disruption of pollination, high risk of insect attack, and consequently harmful effects on the production and product quality. This investigation serves as a basis for making recommendations taking into account the production areas as well as for addressing projected climate change

Climate change and viability of fruit tree orchards in arid area

The Mediterranean region is facing temperature increases due to climate change. More warm conditions across the fruit and nut growing regions are expected to have a great and negative impact in Tunisian arid regions. Chilling trends among the agricultural production areas and their incidence on flowering and fruiting of typical fruit species were investigated. The results showed important declines in winter chill accumulation over the main arid production areas. This lack of chill jeopardizing the flowering and fruiting of fruit species. However, fruit species and cultivars within each fruit species expressed different flowering and fruiting behaviors to warm climate depending on their chilling and heat requirements. Consequently, thermal requirements are a key factor for sustainable fruit trees’ orchards and to select suitable cultivation area. Adoption of appropriate genetic resources could be used to mitigate the harmful effect of global warming in arid regions

Impact of Deficit Irrigation Strategies Using Saline Water on Soil and Peach Tree Yield in an Arid Region of Tunisia

Sustainable fruit orchard development in arid areas is severely affected by the scarcity of fresh water. To mitigate the lack of fresh water, the use of low-quality water for irrigation is becoming a common practice in several margin areas. However, salinity is considered one of the most important environmental constraints limiting the successful crop production. Therefore, the effects of deficit irrigation strategies using saline water (3.1 dS m−1) on soil water content, soil salinity, and yield of commercial peach orchard were investigated. Three irrigation treatments were considered: a Control, full irrigated (FI); and partial root-zone drying (PRD50); and deficit irrigation (DI) strategies irrigated at 50% ETc. These levels of water supply allowed for contrasting watering conditions with clear distinction between irrigation treatments. The differential pattern in soil moisture was accompanied by that of soil salinity with an increase in all FI treatments (16–25%). The results indicated that soil salinity increased with increasing water supply and evaporative demand during the growing season from January (3.2 dS m−1) to August (6.6 dS m−1). Deficit irrigation strategies (DI, PRD50) induced more soil salinity along the row emitter compared to the Control due to insufficient leaching fractions. By the end of the growing season, the soil salinity under long-term saline drip irrigation remained stable (5.3–5.7 dS m−1). An efficient leaching action seemed to be guaranteed by rainfall and facilitated by sandy soil texture, as well as the high evaporative demand and the important salt quantity supplied, which maintain the deficit irrigation strategies as valuable tools for water saving and improving water productivity. The significant water saving of 50% of water requirements induced a fruit yield loss of 20%. For this reason, DI and PRD50 could be reasonable irrigation management tools for saving water and controlling soil salinity in arid areas and on deep sandy soil.The study was supported by Research Agreement Program of Dry Land and Oasis Cropping Laboratory at Arid Regions Institute funded by the Ministry of Higher Education and Scientific Research Tunisia.info:eu-repo/semantics/publishedVersio

Recherche dans des catalogues de composants électroniques virtuels

Cette thèse est portée sur l'échange de composants électroniques virtuels qui sont des blocs pré qualifiés échangés pour la conception de systèmes complexes et la modélisation de ces composants spécifiés à différents niveaux d'abstraction (comportemental, RTL, logique et topologique). Ces principes de modélisation ont amené à la définition de catalogue WEB contenant des données caractéristiques de ces composants virtuels et fondés sur l'étiquetage à base de langage XML (Extented Markup Language) ainsi qu'à la définition et la réalisation d'un générateur de catalogue WEB en langage Java dont l'originalité est dans sa flexibilité et ses capacités d'évolution au cours de son exploitation. Les recherches se sont ensuite portées de façon pointue sur les techniques de recherches associées à ce type de catalogue. Il a contribué de façon significative à la recherche sur attributs XML, à la recherche par fragments de mots, et à la recherche par intervalles sur des données paramétriques.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Responses of olive trees (cv. Chemlali) after five years of experiment to potassium mineral nutrition under rainfed condition

Optimal potassium nutrition is essential to maximize olive tree production. In Tunisia, olive trees are mainly conducted under rainfed conditions and subjected to water and nutrient deficits. An experiment was established in semi arid region to study the response of olive tree to potassium mineral nutrition using potassium sulphate in reference to Control. Potassium was supplied by foliar spray and soil spreading at two levels. Foliar treatments were 50 and 100% of tree requirement. For soil spreading, 100% and 200% of the tree needs were applied. After five of experiment, yield was significantly higher for 100% foliar spray than the control. Leaf mineral analysis revealed a significant increase of K foliar content in response to K supply. Foliar nutrition at 100% of tree needs improved the cumulative yield and olive quality. An increase of average fruit weight, pit ratio was observed for foliar spray treatment. However, oil quality seems to be unaffected with insignificant differences of poly phenols content and fatty acid composition

Responses of olive trees (cv. Chemlali) after five years of experiment to potassium mineral nutrition under rainfed condition

Optimal potassium nutrition is essential to maximize olive tree production. In Tunisia, olive trees are mainly conducted under rainfed conditions and subjected to water and nutrient deficits. An experiment was established in semi arid region to study the response of olive tree to potassium mineral nutrition using potassium sulphate in reference to Control. Potassium was supplied by foliar spray and soil spreading at two levels. Foliar treatments were 50 and 100% of tree requirement. For soil spreading, 100% and 200% of the tree needs were applied. After five of experiment, yield was significantly higher for 100% foliar spray than the control. Leaf mineral analysis revealed a significant increase of K foliar content in response to K supply. Foliar nutrition at 100% of tree needs improved the cumulative yield and olive quality. An increase of average fruit weight, pit ratio was observed for foliar spray treatment. However, oil quality seems to be unaffected with insignificant differences of poly phenols content and fatty acid composition

A core IoT ontology for automation support in edge computing

International audienceAbstract Service providers provision more and more Internet-of-Things (IoT) services in the cloud for dynamicity and cost-effectiveness purposes. This is made possible thanks to the introduction of edge computing that brings additional computing and resources for analytics close to the data sources and thus enables meeting the low latency requirement. Edge nodes should support (i) the heterogeneity of IoT devices (e.g., sensor, actuator) and (ii) characteristics (e.g., mobility, location awareness). IoT is already integrated to the hybrid cloud/edge environment. However, the ecosystem lacks of automation due to the previously mentioned characteristics. Indeed, edge nodes are often manually selected during deployment time, and most of the regular quality-of-service (QoS) management procedures remain difficult to implement. This paper introduces a comprehensive semantic model called EdgeOnto. It encompasses all concepts related to IoT applied in the context of edge computing. The ultimate goal of EdgeOnto is to automate the several steps that make up the IoT services lifecycle in hybrid cloud/edge environment. On the one hand, semantics enable an automatic discovery of the relevant edge nodes that are suitable to host and execute IoT services considering their requirements. On the other hand, it allows supporting the specific QoS procedures that are related to such setting (e.g., low latency, mobility, jitter). The core ontology was designed with the Protégé open-source tool. A smart strawberry farming use case was implemented and evaluated for illustration purposes. The results validate the accuracy and the precision of the designed semantic matchmaker

Phenological and Biochemical Characteristics of Almond Cultivars in Arid Climate of Central Tunisia

Water scarcity is the main limiting factor for fruit trees in arid regions of Tunisia. In this area, almond is widespread, but severe conditions are a key issue for nuts production and kernel quality. In this study, phenological features and kernel quality of local and foreign almond cultivars irrigated with low water quality were investigated. Local cultivars presented an early flowering and seemed to be more appropriate to regional conditions and water salinity. All almond cultivars performed respectable kernel nutritional quality. In conclusion, local cultivars showed better adaptation with early bloom and higher fruit quality under warm conditions

Morphological investigation of genetic diversity of pistachio (Pistacia vera) germplasm in arid land of Tunisia

Background and aims – Pistachio (Pistacia vera L.) is an interesting crop for arid areas, well adapted to marginal lands and to drought conditions. Traditional production areas of Tunisia harbour an interesting diversity of pistachio germplasm. In order to identify and describe this diversity, a field study was conducted in the traditional pistachio production areas of El-Guetar and Sfax in 2004 and 2005. Material and Methods – A total of 256 female and male pistachio specimens were prospected and compared to the main commercial cultivar 'Mateur'. Flowering, tree habit, nut and seed characteristics were determined for 64 pistachio female land races from the El-Guetar oasis and 25 female land races from Sfax. Key results – Differences were observed among all the land races. Flowering and ripening time were particularly variable. Significant variation of nut weight from 0.48 to 1.03g was also observed. Some land races presented nut weight as much as 10% higher than 'Mateur' i.e.Fourati1 and Fourati10 from the region of Sfax and MTSG10, AMHA5 and EPE3 from the El-Guetar oasis. Blank production and split nuts ratio ranged respectively from 2 to 60% and from 14 to 95%. Furthermore, 20 land races had a blank production below 10% while 14 local land races had the split nuts ratio superior to 81% recorded for 'Mateur'. The phenotypic data were evaluated using cluster analysis. Parameters related to leaf and nut size and fruit quality had high discriminating values. Different groups of land races were identified with similar flowering periods, nut and seed characters for each cluster. Conclusion – The evaluation of germplasm in Tunisia revealed promising land races. Additional biochemical and molecular studies will provide the necessary complementary information that could result in potentially valuable land race selection