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1

Reproductive histology of the saddled seabream Oblada melanura in the southern Mediterranean Sea (Tunisian coast)

Kalai Saoussen, Khoufi Widien, Meriem Sadok Ben

Oceanological and Hydrobiological Studies

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2024

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Vol. 53, No. 2

208--217

EN

The saddle seabream, Oblada melanura, is an important species in Mediterranean coastal fisheries. The artisanal gillnet fishery on Tunisia’s northern coast was sampled on a monthly basis between April 2015 and March 2016. The sex ratio varied by month throughout the year, with females dominating from November to December and equal sex ratios during the rest of the year. For both sexes, gonad maturity and gonadosomatic index (IG) indicated that spawning occurs from May to September. In terms of energy investment, fish feed throughout the year. During the spawning period (May to September), gonadal production (IG) appears to be supported by liver reserves (IH). These reserves came from external sources (i.e. food) in the period before spawning. During the spawning period, it was necessary for the fish to continue feeding in order to support their body development. Estimated lengths at 50% maturity were similar for females (L50 = 17.14 cm) and males (L50 = 17.01 cm).

2

Seasonal changes in the reproductive cycle and condition index of the surf clam Mactra stultorum (Mollusca: Bivalvia) in the Gulf of Gabes, Tunisia

Derbali Abdelkarim

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 3

264--272

EN

The reproductive biology of Mactra stultorum fromthe Gulf of Gabes was investigated monthly during a one-year period (2017). This study is the first study examiningits reproductive biology during one-year in the south of Tunisia. The overall samples presented a balanced sex ratio, with males dominating among smaller individuals (< 22mm) and females predominating in larger size classes (> 34 mm). The obtained total sex ratio (F:M) was equal to 1.03:1.The size at first maturity (SL 50%) was 20.43 and 22.10 mm for males and females, respectively. The seasonal variations assessed through macro- and microscopic characteristics in the gonads of both sexes indicated a clearly defined annual reproductive cycle with a principal spawning peak during summer and a resting period during December and January. The reproduction of M. stultorum was strongly influenced by fluctuations in the seawater temperature, as reflected through the temporal variation in the gonadal cycle, condition index (CI) and tissue weight rate (TiWR). If managed properly, M. stultorum is expected to meet thedomestic market demand through artisanal fishery. The adoption and implementation of rules, such as limiting the size of clams, is required to protect this new exploitable fishery resource.

3

The impact of logistics performance index on port infrastructure quality: comparative study Tunisia Morocco

Ben Haj Ahmed Rahid, Bouzir Aida, Benhadj Mbarek Mohamed Heidi, Benammou Saloua

Archives of Transport

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2023

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Vol. 67, iss. 3

71--89

EN

This scientific article examines the relationship between logistics performance indices and port infrastructure quality in Tunisia and Morocco. The quality of port infrastructure (QPI) is an important component of the competitiveness port. It represents a driving force for the economic dynamics. This quality of port infrastructure is a complex subject on which a great deal of research has emerged in the last decade. The logistics performance index (LPI) serves as a crucial indicator to assess the efficiency and effectiveness of a country's logistics system. Accordingly, this paper aims to develop a model for assessing the quality of port infrastructure. The objective is to evaluate the development of port infrastructure to improve the competitiveness of port systems in two North African countries according to nine competitiveness criteria. The analysis involves statistical techniques such as regression modeling to establish relationships. The partial least squares (PLS) regression method is adopted to obtain a reliable estimate, using nine explanatory variables :(performance indicators) (overall, the frequency with which shipments reach their recipient within the set deadlines, The efficiency of customs clearance process, ease of arranging competitively priced shipments, Lead time to import, Lead time to export, competence and quality of logistics services, Liner Shipping Connectivity Index, Container port traffic) and quality of the port infrastructure (QPI) as dependent variable. The results of the analysis highlight the influence of logistics performance indices on port infrastructure quality in Tunisia and Morocco. The results of the test the model using the partial least squares, confirm a significant influence of the identified factors on the quality of port infrastructure. It found show that it is vital to improve logistics performance, which contributes to improving the quality of port infrastructure and increasing maritime trade; which promotes economic growth. Based on the results concerning the importance of port infrastructures, the quality of the latter is empirically examined. Our results show that Morocco tends to improve the quality of its infrastructure in order to improve its competitiveness. The originality of this research work consists in using the PLS (the partial least squares) regression method, which is contrary to previous studies, which have used other econometric methods in the same study field.

4

Upper Albian, Cenomanian and Upper Turonian ammonite faunas from the Fahdène Formation of Central Tunisia and correlatives in northern Algeria

Kennedy William James

Acta Geologica Polonica

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2020

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Vol. 70, no. 2

147--272

EN

Over 130 species are documented from the Upper Albian, Cenomanian and Upper Turonian Fahdène Formation and correlatives in Central Tunisia and northern Algeria, based on material described by Henri Coquand (1852, 1854, 1862, 1880), Léon Pervinquière (1907, 1910), Georges Dubourdieu (1953), Jacques Sornay (1955), and new collections. The material consists predominantly of limonitic nuclei, together with adults of micromorphs. There is no continuous record, and a series of faunas are recognised that can be correlated with the zonation developed in Western Europe. These are the Upper Albian Ostlingoceras puzosianum fauna, Lower Cenomanian Neostlingoceras carcitanense and Mariella (Mariella) harchaensis faunas, the upper Lower to lower Middle Cenomanian Turrilites scheuchzerianus fauna, Middle Cenomanian Calycoceras (Newboldiceras) asiaticum fauna, Upper Cenomanian Eucalycoceras pentagonum fauna, and the Upper Turonian Subprionocyclus neptuni fauna. Two new micromorph genera are described, Coquandiceras of the Mantelliceratinae and Cryptoturrilites of the Turrilitinae. Most of the taxa present have a cosmopolitan distribution, with a minority of Boreal, North American and endemic taxa.

5

Predicting water erosion in arid lands using the GIS-based RUSLE model: A case study of Bedour catchment, central Tunisia

Bedoui Chokri

Journal of Water and Land Development

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2019

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no. 40

59--66

EN

This study was conducted with a view to quantifying soil erosion in arid lands of Tunisia. To do this, we have opted to use the RUSLE model based on geographic information systems. By collecting data on rainfall, soils, vegetation, slopes and conservation practices separately as a layer and determining the pixel values for each of these factors, a quantified assessment of erosion in the basin is obtained. The data superposition and computing, following the model equations and protocol, allowed us to know the spatialized water erosion values at the pixel level. For the whole catchment, the study showed values oscillating between 0 and 163 Mg·ha–1·year–1 with an average annual rate of 3 Mg·ha–1·year–1. With such a low R (rainfall erosivity) factor (between 21.43 and 21.88 MJ·mm·ha–1·h–1·year–1) itself related to low monthly and annual rainfall amounts, the region experiences locally very high annual erosion rates. Soil protection through conservation practices has saved the basin from even higher erosion. While plains cultivated and equipped with contour benches often suffer from low rates of erosion (less than 2 Mg·ha–1·year–1), unused slopes are neglected without protection, resulting in significantly high rates of erosion.

PL

Badania prowadzono, aby ilościowo ocenić erozję gleby na suchych obszarach Tunezji. W tym celu wykorzystano model RUSLE bazujący na systemie informacji geograficznej. Zbiór danych, ich nakładanie i obliczenia prowadzono zgodnie z równaniami i protokołem modelu umożliwiły poznanie erozji w przestrzeni na poziomie pikseli. Badania wykazały, że w całej zlewni nasilenie erozji zmieniało się od 0 do 163 Mg·ha–1·rok–1 ze średnią równą 3 Mg·ha–1·rok–1. Mimo małego współczynnika R (erozyjność opadu), mieszczącego się w granicach 21,43–21,88 MJ·mm·ha–1·h–1·rok–1, który odzwierciedla niewielkie miesięczne i roczne opady, badany region doświadcza lokalnie bardzo wysokiego tempa erozji. Ochrona gleby poprzez odpowiednie działania uratowała zlewnię przed jeszcze większą erozją. Podczas gdy równiny uprawiane z ziemnymi ławami biegnącymi wzdłuż poziomic ulegają mniejszej erozji (mniej niż 2 Mg·ha–1·rok–1), nieuprawiane stoki są pozbawione takiej ochrony, co skutkuje wysokim tempem erozji.

6

Groundwater potentiality assessment in an arid zone using a statistical approach and multi-criteria evaluation, southwestern Tunisia

Msaddek Mohamed Haythem, Souissi Dhekra, Moumni Yahya, Chenini Ismail, Bouaziz Nacira, Dlala Mahmoud

Geological Quarterly

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2019

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Vol. 63, No. 1

3--15

EN

The aim of this paper is to assess the groundwater potentiality using statistical multi-criteria evaluation and AHP (analytic hierarchy process) as an additional method to the hydrogeological research in order to create a map that represents the groundwater potentiality. The extraction of this map is based on the study of multi-criteria input data, such as lineaments, land use, lithology, drainage, slope, soil, rainfall and geomorphology. Weights were assigned using the AHP method to all these multi-influencing factors according to their influence on groundwater potential. Sensitivity analysis was calculated to validate the AHP weights result. The presented methodology has been applied to the Bouhedma region in southwestern Tunisia, located in an arid climate. This technique revealed that very good, good, moderate and poor groundwater potential zones are spread over 382 km2 (26.9%), 437 km2 (30.7%), 552 km2 (38.8%) and 51 km2 (3.6%), respectively. Furthermore, the effect of each influencing factor on groundwater capacity was computed. The results provide significant information and found to be helpful in better planning and management of groundwater resources.

7

Facies and fauna proxies to reconstruct the MIS 5 and MIS 7 coastal environments in Eastern Tunisia

Chakroun A., Zaghbib-Turki D.

Geological Quarterly

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2017

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Vol. 61, No. 1

186--204

EN

This study is based on the analysis of the sedimentology and the fossil assemblages of the Pleistocene deposits in Eastern Tunisia. It aims to establish the different fauna assemblages in order to highlight their paleoenvironments and discuss the importance of the Persististrombus latus distribution especially in the MIS 5e deposits around the Mediterranean Basin. The stratigraphic succession has been divided into two main units. The lower unit is quartz-rich sediment. Its lower marine term revealed well preserved species (Bivalves, Gastropods, Echinoids and Scirripedia) dominated by Acanthocardia, Cerastoderma, Parvicardium, Arca, Donax, Glycymeris, Loripes, Tellina and Cerithium. This fauna is representative of a typical association/biocenosis which may be developed in a sheltered bay, where the hydrodynamism is regularly moderate to low and/or quickly post-mortem buried. The upper unit is carbonated. Its basal term is also rich marine fauna which contains the extant tropical West African species Persististrombus latus. The occurrence of Persististrombus latus in this unit compared to its presence in the whole Mediterranean basin in the Late Pleistocene leads to question its importance in the interpretation of the climate warming during the Late Pleistocene, and to suggest its Atlantic origin.

8

Drought intensity and spatial variability in Gabes Watershed, south-eastern Tunisia

Jemai S., Ellouze M., Agoubi B., Abida H.

Journal of Water and Land Development

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2016

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no. 31

63--72

EN

Chronological series of monthly and annual precipitation data recorded in Gabes Watershed, south-eastern Tunisia, were analyzed. The study is based on the standardized precipitation index (SPI) values, computed for 10 rainfall stations over the period 1987–2012, which corresponds to an observatory period of 25 hydrologic years (from September to August). The results obtained show a great variability in SPI values. The historical evolution of the SPI made it possible to define the periods of excess and deficit, corresponding to wet and dry periods respectively. The wet years were found to be 1989–1990, 1995–1996 and 2006–2007 while the dry years were 1987–1988, 1996–1997, 2000–2001, 2001–2002, 2007–2008, 2008–2009 and 2009–2010. This clearly shows alternating wet and dry periods, but with drought episodes taking prevalence over rainy fronts throughout the study period. Indeed, a high tendency towards a drop in precipitation and important sequences of drought were observed. Spatial variability of drought throughout Gabes Watershed was examined by geostatistical analysis of SPI, as drought and rainfall distribution vary with latitude, longitude, topography and proximity to the Mediterranean Sea. The results obtained showed that, compared to coastal and southern areas, drought was observed to be more important in the West and the North of Gabes Watershed. The SPI showed that moderate droughts are generally more frequent than severe or extreme droughts in most of the Watershed.

PL

Analizowano serie miesięcznych i rocznych opadów notowane w zlewni Gabes w południowo-wschodniej Tunezji. W badaniach wykorzystano wartości standaryzowanego wskaźnika opadu (SPI) obliczonego dla 10 stacji opadowych w latach 1987–2012, co odpowiada okresowi obserwacji równemu 25 latom hydrologicznym (od września do sierpnia). Uzyskane wyniki dowodzą znacznej zmienności wartości SPI. Zmienność w czasie umożliwiła zdefiniowanie okresów nadmiaru i deficytu opadów, które odpowiadają okresom mokrym i suchym. Mokrymi okresami okazały się lata 1989–1990, 1995–1996 i 2006–2007, podczas gdy susze przypadały na lata 1987–1988, 1996–1997, 2000–2001, 2001–2002, 2007–2008, 2008–2009 i 2009–2010. Wskazuje to jasno na naprzemienność okresów mokrych i suchych z przewagą tych ostatnich w czasie objętym badaniami. Rzeczywiście obserwowano tendencję do zmniejszania opadów i do występowania sekwencji okresów suszy. Przestrzenną zmienność suszy w zlewni Gabes badano za pomocą geostatystycznej analizy SPI, ponieważ rozmieszczenie susz i opadów zmienia się wraz z szerokością i długością geograficzną i zależy od topografii oraz odległości od Morza Śródziemnego. Uzyskane wyniki świadczą, że susze były intensywniejsze na zachód i północ od zlewni Gabes niż na obszarach przybrzeżnych i południowych. Wskaźnik SPI dowodzi, że umiarkowane susze są częstsze niż susze intensywne i ekstremalne w większej części zlewni.

9

The lower and middle Berriasian in Central Tunisia: Integrated ammonite and calpionellid biostratigraphy of the Sidi Kralif Formation

Maalaoui K., Zargouni F.

Acta Geologica Polonica

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2016

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Vol. 66, no. 1

43--58

EN

The lower and middle Berriasian sedimentary succession of the Sidi Kralif Formation has been a subject of biostratigraphic study in two key sections in Central Tunisia. Our contribution is an attempt to better define the basal Berriasian interval, between the Berriasella jacobi Zone and the Subthurmannia occitanica Zone. Zonal schemes are established using ammonites and calpionellids, and these permit correlation with other regions of Mediterranean Tethys and beyond. The use of biomarkers afforded by microfossil groups has allowed characterization and direct correlation with four widely accepted calpionellid sub-zones, namely Calpionella alpina, Remaniella, Calpionella elliptica and Tintinopsella longa. The two ammonite zones of Berriasella jacobi and of Subthurmannia occitanica are recognised on the basis of their index species. The parallel ammonite and calpionellid zonations are useful as a tool for correlation and calibration in time and space, thus allowing a better definition of a J/K boundary. The presence of four Berriasian calpionellid bioevents is recognised: (1) the ‘explosion’ of Calpionella alpina, (2) the first occurrence of Remaniella, (3) the first occurrence of Calpionella elliptica and (4) the first occurrence of Tintinopsella longa. The last is here documented as coeval with the presence of Subthurmannia occitanica, which marks the lower/middle Berriasian boundary.

10

Dinoflagellate cysts, palynofacies and organic geochemistry of the Cretaceous-Palaeogene (K–Pg) boundary transition at the Ellès section, northeastern Tunisia

M’Hamdi A., Slimani H., Ismail-Lattrache K. B., Ali W. B.

Annales Societatis Geologorum Poloniae

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2014

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Vol. 84, No. 3

185--212

EN

A palynofacies study carried out across the Cretaceous–Palaeogene (K–Pg) boundary in the El Haria Formation at Ellès, northeastern Tunisia, revealed the presence of organic matter dominated by marine palynomorphs, mainly dinoflagellate cyst assemblages. Continental palynomorphs (sporomorphs) and amorphous organic matter (AOM) are also present in all samples. The total organic carbon (TOC) content is generally less than 0.7 wt.%. The Rock-Eval S1 parameters vary from 0.01 to 0.3 mgHC/g rock. The Rock-Eval S2 parameters vary from 0.15 to 0.57 mgHC/g rock. The hydrogen index (HI) and oxygen index (OI) values range from 61 to 214 mgHC/g TOC and 149 to 638 mgHC/g TOC, respectively. The Tmax values range from 420 to 440°C. The TOC, Rock-Eval pyrolysis and palynofacies analyses indicate that the El Haria Formation is characterized by immature organic matter type II and III and a low thermal alteration index (TAI). Also, the authors present in this paper the biostratigraphic, palaeoenvironmentl and palaeobiogeographic framework for the dinoflagellate cyst assemblages below and above the Cretaceous–Palaeogene boundary in the Ellès section.

11

In situ study of adult Artemia salina morphometry and its relationship to the physicochemical water parameters in the saltwork of Sahline (Tunisia)

Ben Naceur H., Ben Rejeb Jenhani A., Romdhane M.S.

Oceanological and Hydrobiological Studies

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2011

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Vol. 40, No.4

44-51

EN

The morphometric characteristics of the adult natural population of the brine shrimp Artemia salina from the saltwork of Sahline were surveyed in order to establish the relationship between morphometry and environmental water parameters. The field work was performed monthly from October 2005 to June 2006. During this period, the variation in water temperature, salinity, pH, and concentrations of dissolved oxygen and nutrients (orthophosphate, nitrite, nitrate and ammonium) were monitored. Adult Artemia samples (male and female) were randomly collected and stored in plastic containers and transferred to the laboratory for morphometric characterisation. Results show that adult specimens appear in the saltwork of Sahline from December through June. The population sampled in June had significantly lower values in all morphometric characters when compared to the other samples. Concerning male specimens, correlation analysis of the morphometric parameters and environmental conditions indicate that the strongest correlations were between temperature and total length (rxy = -0.656), salinity and total length (rxy = -0.558), and between pH and width of head (rxy = 0.559). For female specimens, the strongest correlations were between total length and salinity (rxy = -0.610), total length and temperature (rxy = -0.537) and between total length and pH (rxy = 0.583). No correlations were observed between dissolved oxygen concentrations or ammonium levels and any morphometric parameters. The principal component analysis (PCA) revealed that diameter of compound eyes, width of second abdominal segment and width of third abdominal segment, for male specimens, and total length, abdominal length and width of the ovisac, for female specimens, are the morphometric parameters that show the greatest variation between samples.

12

Rock type-based characterization and petrophysical analysis of the Silurian Acacus sandstones, Ghadames basin, Tunisia

Axtmann T. C., Baldwin D., Peveraro R., Vessell R.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2009

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T. 35, z. 2/1

541-547

PL

Przedmiotem badań były sylurskie piaskowce Acacus o zróżnicowanych własnościach petrofizycznych, wynikających ze zmiennych warunków sedymentacji. Zmienne zailenie oraz wysoko zmineralizowana woda złożowa spowodowały zaniżenie oporności piaskowców. Dodatkowo, obecność minerałów bogatych w żelazo spowodowała, że standardowa interpretacja profilowań geofizyki otworowej w celu wyznaczenia porowatości była nieefektywna. Wykonano podział piaskowców na 5 typów litologiczno-strukturalnych, oparty na cechach rozpoznanych w wyniku badań laboratoryjnych na próbkach piaskowców. Porowatość i przepuszczalność dla wydzielonych typów piaskowców okazały się znacznie lepiej skorelowane w porównaniu do całej grupy danych. Podział zastosowano podczas interpretacji profilowań geofizyki otworowej.

13

5. Międzynarodowe Sympozjum Projektu IGCP 506 Marine and non-marine Jurassic: global correlation and major geological events Hammamet, Tunezja, 28–31.03.2008

Głowniak E., Grabowski J., Pieńkowski G.

Przegląd Geologiczny

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2008

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Vol. 56, nr 11

967-972

14

The use of trace elements and fossil fluids for the mining prospection in diapir zone (North Tunisia)

Charef A.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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nr 396

29-30