Tillage system affects soil organic carbon storage and quality in Central Morocco

Stabilizing or improving soil organic carbon content is essential for sustainable crop production under changing climate conditions. Therefore, soil organic carbon research is gaining momentum in the Mediterranean basin. Our objective is to quantify effects of no tillage (NT) and conventional tillage (CT) on soil organic carbon stock (SOCs) in three soil types (Vertisol, Cambisol, and Luvisol) within Central Morocco. Chemical analyses were used to determine how tillage affected various humic substances. Our results showed that, after 5 years, surface horizon (0–30 cm) SOC stocks varied between tillage systems and with soil type. The SOCs was significantly higher in NT compared to CT (10% more in Vertisol and 8% more in Cambisol), but no significant difference was observed in the Luvisol. Average SOCs within the 0–30 cm depth was 29.35 and 27.36 Mg ha−1 under NT and CT, respectively. The highest SOCs (31.89 Mg ha−1) was found in Vertisols under NT. A comparison of humic substances showed that humic acids and humin were significantly higher under NT compared to CT, but fulvic acid concentrations were significantly lower. These studies confirm that NT does have beneficial effects on SOCs and quality in these soils

Prédiction du comportement viscoélastique de matériaux composites textiles par une approche d'homogénéisation

International audienceIl est possible d'utiliser des techniques d'homogénéisation analytiques et numériques afin d'évaluer le comportement effectif de matériaux composites textiles composés d'une matrice viscoélastique et de fibres élastiques. Les techniques analytiques permettent d'obtenir des estimations rapides du comportement effectif des composites, en remplaçant les fibres textiles par des inclusions ellipsoïdales, dont la solution théorique est connue. Dans cette étude, les modèles Mori‐Tanaka et auto‐cohérent sont utilisés pour prédire le comportement viscoélastique de composites. Afin de vérifier la validité des modèles, des modèles d'homogénéisation numériques basés sur des simulations par éléments finis ont été utilisés. L'architecture réelle des composites textiles a été reconstituée dans un modèle géométrique solide, qui a été par la suite maillé afin d'évaluer le comportement viscoélastique. La performance des modèles analytiques a été évaluée pour plusieurs fractions volumiques et contrastes, afin de déterminer les limites de la validité de l'approche analytique. Il a été observé que le modèle de Mori‐Tanaka présente les estimations les plus précises aux faibles contrastes et fractions volumiques. De plus, le modèle auto‐cohérent n'arrive pas à reproduire les tendances observées pour la partie transitoire du comportement viscoélastique

Estimation of rice evapotranspiration using a microlysimeter technique and comparison with FAO Penman-Monteith and Pan evaporation methods under Moroccan conditions

This paper reviews field measurements of evapotranspiration from paddy rice fields (ET) in an experimental station in the Gharb region of Morocco, during the summer seasons in 1995 and 1996. The results showed that the seasonal average water consumption of rice was 6.7 mm $\cdot$ day$^{-1}$ with a maximum value of 8.3 mm $\cdot$ day$^{-1}$ during the panicle enlargement stage (R2). The average daily ET for 1996 was compared with US Class `A' open pan evaporation (Ep) and with reference evapotranspiration (ET$_0$) calculated using a validated FAO Penman-Monteith equation. Both methods gave good estimates of ET with a correlation coefficient of 0.78 ($P < 0.001$, slope = 1.06) with Ep and 0.79 with ET$_0$ ($P < 0.001$, slope = 1.3). The derived mean crop coefficients were 1.06 and 1.3, respectively, for the average of the two years. The cumulated ET over the growing season was nearly equal to the cumulated Ep, and greater by about 20% of cumulated ET$_0$. This superiority might be attributed to an advective energy transferred from areas surrounding the rice zone activated by wind speed.Calcul de l'évapotranspiration du riz sous les conditions marocaines : recherche d'une relation simple entre l'évapotranspiration calculée expérimentalement et l'évapotranspiration de référence estimée à partir de l'équation FAO Penman-Montheith et l'évaporation bac. Cet article traite de l'évapotranspiration du riz (ET) mesurée expérimentalement au niveau du champ dans la région rizicole au nord-ouest du Maroc durant la période estivale de 1995 et 1996. Les résultats obtenus ont été comparés à ceux de l'évaporation à partir d'un bac ouvert class `A' (Ep) et avec l'évapotranspiration de référence calculée à partir de l'équation FAO Penman-Monteith (ET$_0$) calibrée sous les conditions marocaines. Les résultats obtenus ont été comparés à l'ET$_0$ et à l'Ep. Des coefficients culturaux ont été alors établis. Les résultats obtenus ont montré que la moyenne saisonnière des besoins en eau du riz était de 6,7 mm $\cdot$ jour$^{-1}$ avec un maximum atteint de 8,3 mm $\cdot$ j$^{-1}$ durant la deuxième décade du grossissement de la panicule avant l'épiaison. L'ET saisonnière en 1996 a montré une corrélation très hautement significative avec les deux modèles, de 0,78 ($P < 0,001$, pente = 1,06) avec Ep et 0,79 avec ET$_0$ ($P < 0,001$, pente = 1,3). les coefficients culturaux moyens des deux années, étaient respectivement de 1,06 (Kcp = ET $\cdot$ Ep$^{-1}$) et 1,3 (KC$_0$ = ET $\cdot$ ET$_0$$^{-1}$). L'ET cumulée durant la saison de croissance égalise avec l'Ep cumulée et dépasse l'ET$_0$ cumulée de 20 %. Cette supériorité pourrait provenir d'une énergie advective transmise des zones sèches, entourant la zone rizicole, activée par le déplacement des vents

Searching for sex- and gender-sensitive tuberculosis research in public health: finding a needle in a haystack

Bilkis Vissandjee,1 Assia Mourid,2 Christina A Greenaway,3 Wendy E Short,4 Jodi A Proctor5 1Faculty of Nursing, Public Health Research Institute, Universit&eacute; de Montr&eacute;al, Montr&eacute;al, Montr&eacute;al, QC, Canada; 2Allied Health Library, Universit&eacute; de Montr&eacute;al, Montr&eacute;al, QC, Canada; 3Department of Medicine, McGill University, Division of Infectious Diseases, Jewish General Hospital, Montr&eacute;al, QC, Canada; 4Faculty of Humanities and Social Sciences, School of Social Sciences, University of Queensland, St Lucia, QLD, Australia; 5School of Social Work, McGill University, Montr&eacute;al, QC, Canada Abstract: Despite broadening consideration of sex- and gender-based issues in health research, when seeking information on how sex and gender contribute to disease contexts for specific health or public health topics, a lack of consistent or systematic use of terminology in health literature means that it remains difficult to identify research with a sex or gender focus. These inconsistencies are driven, in part, by the complexity and terminological inflexibility of the indexing systems for gender- and sex-related terms in public health databases. Compounding the issue are authors&rsquo; diverse vocabularies, and in some cases lack of accuracy in defining and using fundamental sex&ndash;gender terms in writing, and when establishing keyword lists and search criteria. Considering the specific case of the tuberculosis (TB) prevention and management literature, an analysis of sex and gender sensitivity in three health databases was performed. While there is an expanding literature exploring the roles of both sex and gender in the trajectory and lived experience of TB, we demonstrate the potential to miss relevant research when attempting to retrieve literature using only the search criteria currently available. We, therefore, argue that for good clinical practice to be achieved; there is a need for both public health researchers and users to be better educated in appropriate usage of the terminology associated with sex and gender. In addition, public health database indexers ought to accept the task of developing and implementing adequate definitions of sex and gender terms so as to facilitate access to sex- and gender-related research. These twin advances will allow clinicians to more readily recognize and access knowledge pertaining to systems of redress that respond to gendered risks that compound existing health inequalities in disease management and control, particularly when dealing with already complex diseases. Given the methodological and linguistic challenges presented by the multidimensional and highly contextual nature of definitions of sex and gender, it will be important that this review task be undertaken using a multidisciplinary approach. Keywords: sex, gender, tuberculosis, literature search, indexing, databases, terminological accuracy, keywords searc