Landsat 8 and Sentinel 2 for mapping Borj Touil’ irrigated district land use/land cover and water requirements

Landsat 8 et Sentinel 2 pour la cartographie des occupations du sol et des besoins en eau du périmètre irrigué de Borj Touil 

BETTAIBI A.^1,2

ERGAIEG K.¹

LABIEDH C.³

ANANE M.²

¹ Ecosystems and Aquatic Resources Research Unit, National Agronomic Institute of Tunisia (INAT), 43 Avenue Charles Nicolle, Tunis 1082, University of Carthage, Tunisia

² Laboratory of Wastewater and Environment, Water Research and Technologies Center (CERTE) Ecopark Borj Cedria, Touristic road of Soliman, BP273, Soliman 8020, Tunisia 

³ Regional Commissariat for Agricultural Development of Ariana (CRDA), Tunisia

Abstract - From Mediterranean leadership to the current deceleration, the reuse of reclaimed water for irrigation in Tunisia still arouse as much excitement and interest. The main objective of this work is to assess the satellite image time series contribution to raise knowledge of operation and management system of irrigated public districts with reclaimed water. To do so, i) the Borj Touil’ irrigated district land use/land cover (LULC) of winter 2015/2016 and summer 2016 were mapped using Landsat 8 and Sentinel 2 satellites data, ii) the water requirements of the main crops of this area were mapped and estimated coupling remote sensing and CROPWAT model, and iii) the obtained information was compared to the available official statistics. The results are threefold: (i) the accuracy of summer LULC map obtained using decision tree followed by maximum likelihood classification is satisfactory, and (ii) irrigated agricultural intensification rates estimated by remote sensing are close to those provided by the official institutions, being respectively 11.5% and 12%. However, a notable discrepancy is observed for the cropped areas as well for the amount of irrigation water supplied and needed. In winter the water provided for irrigation is lower than needed while in summer is the other way around. (iii) Integrating remote sensing techniques with conventional methods offer an important added-value for improving statistics accuracy on districts irrigated with reclaimed water and to raise knowledge of their operation and management systems.

Keywords: reclaimed water reuse; irrigated district; land use/land cover; water requirements; remote sensing; Cropwat.

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Etude de la qualité bactériologique des laits en poudre destinés à la transformation en Tunisie.

W. OUESLATI¹

O. NASRAOUI¹ 

F. SOUISSI¹

¹Laboratory of Food Microbiology, National School of Veterinary Medicine of Sidi Thabet, University Manouba, Tunisia (LR14AGR03)

Abstract - Our study aims to assess the bacteriological quality of powdered milk intended for processing in Tunisia. This assessment allows verifying the compliance of these products with the regulatory criteria and their aptitude for technological transformation, particularly in the cheese industry. Our study shows that 20% (6/30) of the milk powder batches analyzed are of unsatisfactory bacteriological quality. The exceeding of the revealed limit values relates to technological and process hygiene criteria. Thus, corrective measures must be applied by manufacturers as stipulated by regulation n°2073/2005 amended by European commission regulation n°1441/2007 of December 05, 2007. These measures consist of controlling the effectiveness of heat treatment, preventing recontamination of finished products and improving production hygiene. The use of these powdered milks loaded with Clostridium tyrobutyricum spores is strongly discouraged in order to prevent the phenomenon of late swelling, especially in cooked pressed cheeses.

Keywords : Powdered milk, bacteriological quality, spore-forming bacteria, food safety criteria, process hygiene criteria, Clostridium tyrobutyricum, late swelling of cheeses.

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MNA JEDIDI NEJI¹

RYM BOUHLAL BEN HADJ ALOUANE¹

KAOUTHER BEN MAHMOUD²

NOURA JEMAI³

OLFAAYARI¹

AHMED JEMMALI³

¹Laboratory of Horticulture, National Institute of Agronomic Research of Tunisia. Rue Hedi Karray, 1004, El- Menzah, University of Carthage-Tunisia.

²Laboratory ofAgronomic Science and Technology, National Institute of Agronomic Research of Tunisia. Rue Hedi Karray, 1004, El- Menzah, University of Carthage- Tunisia.

³ Laboratory of Plant Protection, National Institute of Agronomic Research of Tunisia. Rue HediKarray, 1004, El- Menzah, University of Carthage -Tunisia.

Abstract - Opuntia ficus-indica, known as prickly pear, is the most important plant species in the Cactaceae family. It is known as a multipurpose use plant with great worldwide interest because of his ecological and socioeconomic virtues such as the combat against erosion and desertification. In prickly pear multiplication by somatic embryogenesis was very important as a first step to induce mutation from suspected fertilized ovules. In this study, our interest has been oriented to identify the origin of somatic embryogenesis initiation. For this purpose, morphological study linked to anatomical investigation, made in the early stages of induction revealed that the tissue involved in this callogenesis was none other than the cambial section of vascular bundle of the funicular tissue.

Keywords: Opuntia ficus indica; Somatic embryogenesis; Ovular Tissue; Anatomical studies.

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Effet du mode de conduite (Bergerie vs. Pâturage), de la nature de l’espèce fourragère et de la complémentation sur la production laitière des brebis de race Sicilo-sarde 

Y. YAGOUBI¹

S. SMETI¹

N. ATTI¹

¹University of Carthage, National Institute of Agronomic Research of Tunisia (INRAT), Animal and Forage Productions Laboratory, rue Hédi Karray, 2080 Ariana, Tunisia.

Abstract - The aim of this work is to study the milk production and quality of sheep raised on feedlot or grazing on pasture on cultivated ryegrass and barley and according to the nature of the supplementation. For that, 76 Sicilo-Sarde ewes were divided into 6 homogeneous groups according to parity, litter size and milk production at half weaning of the lambs. Two groups raised on feedlot were fed with 3 kg of oat silage and 500 g of vetch-oat hay and 500 g of concentrate C1 (standard concentrate) for BC1 and C2 (FP10 concentrate) for BC2. Two groups O1 and O2 graized on green barley where one group did not receive any supplementation (OC0) and the other one (OC3) received 300 g of C3 concentrate (Soybean meal FP10). The last two groups RC1 and RC3 graized the ryegrass while receiving 300 g of C1 for RC1 and C3 for RC3. The biomass production averaged 3.5 and 2 tonnes of dry matter (DM)/ha for barley and ryegrass, respectively. The milk production of ewes was significantly higher on pasture of both forage species than that of ewes in sheepfold. The nature of forage species did not affect milk production even in the absence of supplementation for OC0 group. The daily milk production was 359, 338, 599, 647, 592 and 476 ml, respectively for BC1, BC2, OC0, OC3, RC1, RC3. The milk produced in the sheepfold was significantly richer in fat and in protein than that produced in barley and ryegrass (P<0.05).

Keywords: Sicilo-Sarde ewes; milk production; sheepfold; pasture; supplementation; milk quality

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ASMA AISSA¹

IMEN CHAKROUN¹

ROUA REJEB¹

MADIHA HAJ AYED¹

¹Institut Supérieur Agronomique de Chott-Mariem, Sousse – Université de Sousse- Tunisie

Abstract - The present study aims to evaluate the effect of the substitution of carob pods to barley, on apparent nutrient digestibility of rabbit feeds. A total number of 30 male rabbits of 7 weeks of age and with a live body weight of 1116 ± 118 g were randomly allotted to 3homogeneous groups (10 rabbits/group, 1 rabbit/cage). Each group received one of the experimental diets Control, Carob 10 and Carob 20, containing 0, 10 and 20% of carob pods, respectively. The assay was conducted, according to the European reference method reported by Perez et al. (1995). Digestibility of dry matter (DMD), organic matter (OMD), crude protein (CPD), crude fiber (CFD), neutral detergent fiber (NDFD), acid detergent fiber, (ADFD) and hemicelluloses (HCD) were determined. The results showed that carob pods reduced diet digestibility in rabbits. This effect can be attributed mainly to its relatively high lignocellulosic content. Indeed, if the incorporation rate reached20 %, the Acid Detergent Fiber and Acid Detergent Lignin content would increase, respectively, to 23 and 14 % DM.

Keywords: Carob, Rabbits, apparent digestibility

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