26 research outputs found
Rural Dynamics and Forest Conservation in Northern Tunisia
This paper will first examine the causes of the ongoing forest crisis that was inherited from the French protectorate and that is associated with the agricultural and forest policies followed by the Tunisian government. Strict forest regulations have failed to contain increased population pressure on forest lands. This is mainly due to the crisis of traditional agriculture that has been undermined by large and modern production-driven exploitation of large basins, which is promoted by the agricultural policies of the state and supported by a powerful urban framework. Then, this article will show how, in recent decades, the multiplicity of original rural dynamics tends to give new clear-cut characteristics to the rural populations and their territories in the mountain forests. In particular, it focuses on issues like the reshaping of rural communities, diversification of peasantsâ income generation activities, and the dynamism of certain peasant economy. These sufficiently advanced changes are lightening the pressure of the population on the forest lands, and they especially modify Man-vegetation relationships, towards the reconciliation between the peasants and the forests. They therefore call for a re-thinking of forest policies to clearly integrate resident peasants into forest management and development
A new species for the spontaneous vascular flora of Tunisia: Rhus coriaria L.
This account describes the morphological characteristics, the auto-ecology and the economic and environmental values of Rhus coriaria, a specie which has been recently found in the northwestern side of Jebel GorrĂąa (Tunisian High
Tell
Joumine Marsh; National Park of Ichkeul, Tunisia: floristic diversity, vegetation mapping and dynamics (1925-2011)
The vegetation of Joumine Marsh (National Park of Ichkeul, Tunisia) has been
studied from 2005 to 2011 with the aims: (1) to characterize the present-day status of the marsh vegetation
based on plant inventories and phytosociological surveys, (2) to identify the influence of interannual hydrological
changes on the plant distribution, and (3) to reconstruct, on the basis of previous works, the vegetation
dynamics over the past 86 years (1925-2011). Results reveal the regression and sometimes the local extinction
of the plants of temporary freshwater habitats, and their replacement by halophilous, cultivation-tolerant,
footpath and grazing-tolerant species. Such changes express the artificialisation of the marsh. The mid-term
dynamics of Joumine Marsh (1925-2011) is characterized by four periods: (1) before the first hydrological
developments realized on the Joumine Wady in 1948, the marsh was dominated by the helophytic formation
of Bolboschoenus glaucus and Schoenoplectus litoralis; (2) between 1948 and the putting into service of the
Joumine Dam in 1982/83, the helophytic vegetation remained dominant; (3) between 1982-1983 and the summer
2002, because of an inappropriate management of the reservoir (without freshwater release), the salinity of
the marsh has considerably increased, triggering the decline of the hydrophilous vegetation and the expansion
of salt scrubs of Sarcocornia fruticosa; (4) finally, since autumn 2002, occasional releases of freshwater from
the Joumine reservoir and the realization of new hydrological developments on the Joumine ditch lead to the
inundation and washing of the marsh. These changes have induced the partial replacement of the salt scrubs by
renewed helophytic herbaceous formations. This study reveals the significance of the ratio âhydro-hygrophilous
plants/halophilous plantsâ as an indicator of the health of coastal wetlands. This ratio, as a simple tool for
helping the management, may be used at the scale of the entire system lake-marsh of IchkeulLa végétation du marais de Joumine (Parc National de l'Ichkeul, Tunisie) a été étudiée entre 2005 et 2011 dans les buts: (1) de caractériser l'état actuel de la végétation du marais sur la base d'inventaires floristiques et de
relevés phytosociologiques, (2) d'identifier l'influence des changements hydrologiques interannuels sur la répartition de la végétation, et (3) de reconstruire, sur la base de travaux antérieurs, la dynamique de la végétation sur 86 ans (1925-2011). Les résultats révÚlent la réduction, voire
la disparition, des espÚces inféodées aux milieux temporaires d'eau douce, et leur remplacement par des espÚces halophiles, adventices, rudérales et indicatrices de surpùturage. Ces changements dénotent l'artificialisation du marais. La dynamique à moyen terme de la végétation du marais de
Joumine (1925-2011) est caractérisée par quatre périodes: (1) avant les premiers aménagements hydrauliques réalisés sur l'oued Joumine en 1948, le marais était dominé par la scirpaie à Bolboschoenus glaucus et Schoenoplectus litoralis ; (2) entre 1948 et la mise en service du barrage de
Joumine en 1982/83, la scirpaie est restée dominante ; (3) entre 1982-83 et l'été 2002, sous l'effet d'une gestion inappropriée du barrage (sans lùcher d'eau douce), la salinité du marais a considérablement augmenté, provoquant le déclin de la végétation hydro-hygrophile et l'extension de la
sansouïre à Sarcocornia fruticosa ; (4) enfin, depuis l'automne 2002, des lùchers occasionnels d'eau douce à partir du barrage de Joumine et la réalisation de nouveaux aménagements sur le canal de Joumine ont conduit à l'inondation et au lessivage du marais. Ces changements ont entraßné le
déclin de la végétation halophile au profit de la régénération de la scirpaie. Cette étude met en évidence l'importance du rapport « végétation hydro-hygrophile/végétation halophile » en tant qu'indicateur de l'état de santé de marais littoraux. Ce rapport, qui apparaßt comme un outil simple
d'aide Ă la gestion, peut ĂȘtre exploitĂ© Ă l'Ă©chelle de l'ensemble du systĂšme lac-marais de l'Ichkeul
Rare, endemic and threatened vascular flora of Tunisian wetlands
Tunisian wetlands
harbour a large floristic richness, estimated at 407 species representing 228 genera and 75 families. This flora
comprises species strictly limited to wetlands, and species originating from surrounding lands. It is characterized
by a big proportion of rare and/or threatened taxa (~ 29 %). Kroumirie is the richest region, with 290
taxa among which 54 are considered as very rare, rare or infrequent, because of their limited distribution
area, generally located in frail or degraded ecosystems. The preservation of this exceptional biodiversity,
threatened on short term, implies the urgent development of scientific investigations and adapted protection
measuresLes zones humides de Tunisie présentent une grande richesse floristique, évaluée à 407 espÚces représentant 228 genres et 75 familles. Ces espÚces sont, soit strictement inféodées aux zones humides, soit transgressives des milieux
terrestres. Cette flore est caractĂ©risĂ©e par une forte proportion des taxons rares et/ou menacĂ©s (⌠29 %). La Kroumirie est la rĂ©gion la plus riche, avec 290 taxons dont 54 sont considĂ©rĂ©s comme trĂšs rares, rares ou peu rĂ©pandus, en raison de leur rĂ©partition rĂ©duite et gĂ©nĂ©ralement situĂ©e
au niveau d'écosystÚmes trÚs fragiles ou dégradés. La préservation de cette biodiversité exceptionnelle et menacée à court terme nécessite la mise en place urgente d'études scientifiques et de mesures de protection appropriées
Influence of grazing on structure, composition and dynamics of vegetation in Mediterranean temporary pools (northern Tunisia)
Three temporary pools of Sejenane region (northern Tunisia)
have been studied with the aims of characterizing their vegetation, and of specifying the impact of grazing
on their structure, composition and dynamics. Permanent transects of quadrats have been surveyed in spring
and summer during two (not-grazed pool) to three years (grazed pools). The vegetation of the three pools
is organized in three concentric belts related to the topographic gradient. The between-years dynamics is
strongly characterized by the alternation of distinct spring and summer vegetations. Grazing appears as the
main control of the composition and structure of hydrophytic plant communities. It prevents the colonization
by competitive, perturbation-sensitive species, and favours the persistence of annual, light-demanding
dwarf plants. In order to protect the biodiversity of these rare habitats in Tunisia, it is necessary to maintain,
through an adapted management of grazing, a landscape mosaic of grazed and not-grazed zonesTrois mares temporaires de la région de Sejenane (Tunisie septentrionale) ont été étudiées
afin de caractĂ©riser leur vĂ©gĂ©tation et de prĂ©ciser lâinfluence du pĂąturage sur sa structure, sa composition et
sa dynamique intra- et interannuelle. Des transects de quadrats permanents ont été suivis au printemps et en
été durant deux (mare non pùturée) à trois ans (mares pùturées). Le cortÚge floristique des mares étudiées est
organisé en trois ceintures concentriques liées au gradient topographique. La dynamique intra-annuelle de la
vĂ©gĂ©tation est nettement marquĂ©e par lâalternance de cortĂšges printaniers et estivaux distincts. Le pĂąturage
apparaßt comme le principal facteur contrÎlant la composition et la structure des communautés végétales
hydrophytiques. Il limite le développement des espÚces compétitives sensibles aux perturbations et favorise
le maintien dâune flore de petite taille, thĂ©rophytique et hĂ©liophile. Afin de prĂ©server la biodiversitĂ© de
ces habitats rares en Tunisie, il apparaßt nécessaire de maintenir, par une gestion adaptée du pùturage, une
mosaïque paysagÚre de zones non pùturées et pùturée
Dynamiques rurales et conservation forestiĂšre dans le Nord de la Tunisie
This paper will first examine the causes of the ongoing forest crisis that was inherited from the French protectorate and that is associated with the agricultural and forest policies followed by the Tunisian government. Strict forest regulations have failed to contain increased population pressure on forest lands. This is mainly due to the crisis of traditional agriculture that has been undermined by large and modern production-driven exploitation of large basins, which is promoted by the agricultural policies of the state and supported by a powerful urban framework. Then, this article will show how, in recent decades, the multiplicity of original rural dynamics tends to give new clear-cut characteristics to the rural populations and their territories in the mountain forests. In particular, it focuses on issues like the reshaping of rural communities, diversification of peasantsâ income generation activities, and the dynamism of certain peasant economy. These sufficiently advanced changes are lightening the pressure of the population on the forest lands, and they especially modify Man-vegetation relationships, towards the reconciliation between the peasants and the forests. They therefore call for a re-thinking of forest policies to clearly integrate resident peasants into forest management and development
Une nouvelle espÚce pour la flore vasculaire spontanée de la Tunisie : Rhus coriaria L
Summary. â A new species for the spontaneous vascular flora of Tunisia : Rhus coriaria L.â This account describes the morphological characteristics, the auto-ecology and the economic and environmental values of Rhus coriaria, a specie which has been recently found in the northwestern side of Jebel GorrĂąa (Tunisian High Tell).Abaza Khaled, Gammar Amor Mokhtar, Ghrabi Gammar Zeineb. Une nouvelle espĂšce pour la flore vasculaire spontanĂ©e de la Tunisie : Rhus coriaria L. In: Revue d'Ăcologie (La Terre et La Vie), tome 65, n°2, 2010. pp. 179-184
Distribution and infraspecific morpho-ecological variability of Ambrosina bassii (Araceae) an endemic of western-central Mediterranean
International audienc
Le marais de Joumine, Parc National de lâIchkeul, Tunisie : diversitĂ© floristique, cartographie et dynamique de la vĂ©gĂ©tation (1925-2011)
Joumine Marsh ; National Park of Ichkeul, Tunisia : floristic diversity, vegetation mapping and dynamics (1925-2011).
The vegetation of Joumine Marsh (National Park of Ichkeul, Tunisia) has been studied from 2005 to 2011 with the aims : (1) to characterize the present-day status of the marsh vegetation based on plant inventories and phytosociological surveys, (2) to identify the influence of interannual hydrological changes on the plant distribution, and (3) to reconstruct, on the basis of previous works, the vegetation dynamics over the past 86 years (1925-2011). Results reveal the regression and sometimes the local extinction of the plants of temporary freshwater habitats, and their replacement by halophilous, cultivation-tolerant, footpath and grazing-tolerant species. Such changes express the artificialisation of the marsh. The mid-term dynamics of Joumine Marsh (1925-2011) is characterized by four periods : (1) before the first hydrological developments realized on the Joumine Wady in 1948, the marsh was dominated by the helophytic formation of Bolboschoenus glaucus and Schoenoplectus litoralis ; (2) between 1948 and the putting into service of the Joumine Dam in 1982/ 83, the helophytic vegetation remained dominant ; (3) between 1982-1983 and the summer 2002, because of an inappropriate management of the reservoir (without freshwater release), the salinity of the marsh has considerably increased, triggering the decline of the hydrophilous vegetation and the expansion of salt scrubs of Sarcocornia fruticosa ; (4) finally, since autumn 2002, occasional releases of freshwater from the Joumine reservoir and the realization of new hydrological developments on the Joumine ditch lead to the inundation and washing of the marsh. These changes have induced the partial replacement of the salt scrubs by
renewed helophytic herbaceous formations. This study reveals the significance of the ratio âhydro-hygrophilous plants/halophilous plantsâ as an indicator of the health of coastal wetlands. This ratio, as a simple tool for helping the management, may be used at the scale of the entire system lake-marsh of Ichkeul.La vĂ©gĂ©tation du marais de Joumine (Parc National de lâIchkeul, Tunisie) a Ă©tĂ© Ă©tudiĂ©e entre 2005 et 2011 dans les buts : (1) de caractĂ©riser lâĂ©tat actuel de la vĂ©gĂ©tation du marais sur la base dâinventaires floristiques et de relevĂ©s phytosociologiques, (2) dâidentifier lâinfluence des changements hydrologiques interannuels sur la rĂ©partition de la vĂ©gĂ©tation, et (3) de reconstruire, sur la base de travaux antĂ©rieurs, la dynamique de la vĂ©gĂ©tation sur 86 ans (1925-2011). Les rĂ©sultats rĂ©vĂšlent la rĂ©duction, voire la disparition, des espĂšces infĂ©odĂ©es aux milieux temporaires dâeau douce, et leur remplacement par des espĂšces halophiles, adventices, rudĂ©rales et indicatrices de surpĂąturage. Ces changements dĂ©notent lâartificialisation du marais. La dynamique Ă moyen terme de la vĂ©gĂ©tation du marais de Joumine (1925-2011) est caractĂ©risĂ©e par quatre pĂ©riodes : (1) avant les premiers amĂ©nagements hydrauliques rĂ©alisĂ©s sur lâoued Joumine en 1948, le marais Ă©tait dominĂ© par la scirpaie Ă Bolboschoenus glaucus et Schoenoplectus litoralis ; (2) entre 1948 et la mise en service du barrage de Joumine en 1982/ 83, la scirpaie est restĂ©e dominante ; (3) entre 1982-83 et lâĂ©tĂ© 2002, sous lâeffet dâune gestion inappropriĂ©e du barrage (sans lĂącher dâeau douce), la salinitĂ© du marais a considĂ©rablement augmentĂ©, provoquant le dĂ©clin de la vĂ©gĂ©tation hydro-hygrophile et lâextension de la sansouĂŻre Ă Sarcocornia fruticosa ; (4) enfin, depuis lâautomne 2002, des lĂąchers occasionnels dâeau douce Ă partir du barrage de Joumine et la rĂ©alisation de nouveaux amĂ©nagements sur le canal de Joumine ont conduit Ă lâinondation et au lessivage du marais. Ces changements ont entraĂźnĂ© le dĂ©clin de la vĂ©gĂ©tation halophile au profit de la rĂ©gĂ©nĂ©ration de la scirpaie. Cette Ă©tude met en Ă©vidence lâimportance du rapport «vĂ©gĂ©tation hydro-hygrophile/ vĂ©gĂ©tation halophile » en tant quâindicateur de lâĂ©tat de santĂ© de marais littoraux. Ce rapport, qui apparaĂźt comme un outil simple dâaide Ă la gestion, peut ĂȘtre exploitĂ© Ă lâĂ©chelle de lâensemble du systĂšme lac-marais de lâIchkeul.Ouali Mounira, Daoud-Bouattour Amina, Etteieb Selma, Gammar Amor Mokhtar, Ben Saad-Limam Samia, Ghrabi Gammar Zeineb. Le marais de Joumine, Parc National de lâIchkeul, Tunisie : diversitĂ© floristique, cartographie et dynamique de la vĂ©gĂ©tation (1925-2011). In: Revue d'Ăcologie (La Terre et La Vie), tome 69, n°1, 2014. pp. 3-23