Reboisement méditerranéen avec des boues résiduaires urbaines. Essai de Carpiagne (1982-1987).

Dans l'hypothèse d'un traitement thermique des boues résiduaires urbaines produites par sa future station d'épuration, la ville de Marseille avait chargé le Cemagref de réaliser un reboisement expérimental avec le concours de la Société du Canal de Provence et l'aval de l'ONF. Objectifs poursuivis..

Can we use shelterwoods in Mediterranean pine forests to promote oak seedling development?

International audienceThe use of shelterwoods to favour the development of natural or underplanted seedlings is common in temperate forests but rare in the pine forests of the Mediterranean area. Our aim was to assess the use of shelterwoods in Aleppo pine (Pinus halepensis) woodlands in southern France to promote the survival and growth of two co-occurring oak species: the deciduous Quercus pubescens and the evergreen Quercus ilex. Twelve Aleppo pine stands were selected and differentially thinned to create a light shelterwood (G = 32 m2/ha, irradiance 13%), a medium shelterwood (G = 19 m2/ha, irradiance 33%) and a dense shelterwood (G = 10 m2/ha, irradiance 52%). A total of 1248 sowing points, half composed of Q. pubescens and half of Q. ilex, were then set up in these three conditions. Seedling survival and growth were monitored for three years and plant stress was assessed by measuring predawn leaf potential and photosynthetic performance through the Fv ∕Fm ratio. Soil moisture was also recorded at two depths during two growing seasons. Survival was high for both species in all three conditions due to three consecutive wet years. The lowest survival was recorded for Q. pubescens in the dense shelterwoods. Growth in diameter and height increased from the dense to the light shelterwoods. Shrubs developed more strongly in the light shelterwood, and increasing shrub cover enhanced height growth. Photosynthetic performance was lowest for Q. pubescens in dense shelterwoods and highest in light shelterwoods, whereas the reverse was true for Q. ilex. The lowest predawn potentials were recorded in the dense shelterwoods even though higher soil water content values were measured in this treatment during the summer drought. We show that light shelterwoods were more beneficial to growth than denser ones, indicating control by light availability during the three years of the study. However, as lower soil moisture and faster understorey development were also recorded in this condition, more extended observation is needed to determine whether this benefit persists in subsequent years

Rethinking Négritude: Aimé Césaire & Léopold Sédar Senghor and the Imagination of a Global Postcoloniality

This dissertation calls into question the critique that has depicted the Francophone literary movement known as Negritude as a sole vehicle of black essentialism. By looking at recently published anthologies, archival documents, and lesser-known texts from 1935 to 1966, I show that in addition to the discourse on a fixed ‘blackness’ engraved in the neologism ‘Negritude,’ there is another set of discourses that forces us to rethink the movement as a philosophy of becoming. In particular, this dissertation stages the year 1948, when Jean-Paul Sartre gave Negritude its fame with the publication of his influential essay “Black Orpheus,” as a pivot for the definition of the movement as well as its reception. Since 1948, most of the critical engagement with Negritude has happened either through a reading of Sartre’s essay or the limited corpus that was available at the time. I thus argue that, by reading a broader range of the poets of Negritude’s literary and cultural production, one gets a sense that their vindication of Blackness is not only an essentialized invocation of a romanticized past, it is also an imagined unity within an evolving postcoloniality. This dissertation covers three areas within which this constantly reimagined unity is staged, from the youthful local publications of Aimé Césaire and Léopold Sédar Senghor from 1935 to 1948, to their mature global interactions as statesmen in Dakar, Fort-de-France, Paris and Rome from 1948 to 1966. First, it looks at language and analyzes the relation of the poets to French. While the choice to adopt the idiom of the former colonizer has been criticized by merely every reader of Negritude, I show that they used French as a tool enabling violation, negotiating their relation to the metropole as well as other colonies. Second, it interrogates the often overlooked concept of métissage as common element for colonized subjects. With particular attention to problems of translation, I analyze how the poets used métissage as a political and ethical concept in order to reach to the African diaspora without referring to Europe as the unavoidable mediator. Third, it focuses on the First World Festival of Negro Arts held in Dakar in 1966 as instrument for political practice. By investigating extensive documentation on the Festival’s organization, especially the influential role and presence of the United States, I show that art was used as a political tool to stage postcolonial unity in an otherwise global and competitive diversity

The Implications of Case-based Learning (CBL) on Biochemistry Education: An Integrative Literature Review

The COVID-19 has significantly impacted the world as we know it, especially in higher education institutions. In response to COVID-19, most colleges and universities were forced to close their doors to students and switch to online learning over Zoom. Although most students are adjusted well to this new mode of education, other students, such as individuals pursuing degrees in the sciences, have difficulty adapting to the online mode of instruction. Case-based learning (CBL) is considered one of the best strategies in teaching a course like Biochemistry in a large classroom setting. Implementing CBL in biochemistry education may increase student engagement in the curriculum. Students will connect the material they learned in class to their daily lives, promoting critical thinking. The purpose of this review was to determine the effects of CBL in biochemistry education. This integrative review will focus on the various CBL study that implored in a biochemistry class setting. The review aimed to determine the implication of CBL in teaching biochemistry and assess students\u27 views regarding the CBL

Les forêts mélangées en région méditerranéenne : quels bénéfices et comment créer le mélange ? -

Les forêts mélangées sont devenues un enjeu majeur de la gestion forestière pour les nombreux avantages qu'on leur attribue. Plusieurs travaux montrent que la productivité des formations végétales mélangées est supérieure à celle des formations pures et cela semble être le cas pour les formations forestières. Les forêts mélangées sont moins sensibles aux attaques par les ravageurs en particulier pour les insectes. Elles semblent héberger une biodiversité plus forte mais les travaux ne sont encore que peu nombreux et partiels. Le mélange des essences permet d'obtenir une meilleure résilience face aux perturbations anthropiques en particulier l'incendie. Cependant cette résilience n'est pas systématique et c'est surtout l'adaptation des essences au feu qui est déterminante. En zone méditerranéenne le mélange pin-chêne est le plus fréquent. Des exemples de création de ce type de mélange sont présentés dans diverses situations : i) lors de la régénération des pinèdes avec introduction de semis de chênes, ii) lors de coupes d'éclaircie de différentes intensités et introduction de chênes, iii) à partir de plantation sur des zones ouvertes

Flore méditerranéenne et changement climatique : la course-poursuite est engagée -

Cet article décrit la « course-poursuite » engagée entre changement climatique et flore méditerranéenne. En effet, on observe déjà de sérieuses modifications de composition de la flore méditerranéenne. En outre, la compensation du déficit hydrique d'origine climatique par des conditions stationnelles favorables, qui jusqu'à présent permettait la survie d'espèces mésophiles, n'est plus suffisante. Les stratégies d'adaptation des plantes devraient permettre une résistance temporaire et partielle, mais même les scénarios climatiques les plus optimistes ne laisseront guère le temps à cette stratégie de se mettre en plac