The 12th “Iter Mediterraneum” in Tunisia, 24 March – 4 April 2014

The organization and logistics of the 12th OPTIMA Iter in Tunisia from 24 March to 4 April 2014 by OPTIMA and ATUTAX is here reported. The material used and the workflow are illustrated as reference for the organization of future similar collaborative botanical excursions

Composición del aceite de la semilla del pistacho (Pistacia vera): efectos de la situación geográfica y de la variedad

This study was aimed at characterizing four Tunisian pistachio cultivations (Pistacia vera) from the Mateur (North), Nabeul (North-East), Kairouan (Middle) and Sfax (Middle- East) regions and two varieties, Mateur and Ohadi, considering fatty acid composition and main lipid class contents (polar lipids, diacylglycerols, triacylglycerols and free fatty acids) in ripe seeds. Lipid classes were separated using thin layer chromatography, and fatty acid methyl esters (FAMEs) were analyzed by gas chromatography. Oleic acid (C18:1 Δ9) was the major fatty acid for all samples; those of the Mateur region (the northern region) differed significantly with the lowest content in C18:1 (54.2 % of total fatty acids) and the highest in C18:2 (24.1 %). The total amount of fatty acids (TFA) in the seeds of Ohadi variety was significantly lower than that of the Mateur variety from the Sfax region. Triacylglycerols were most abundant in pistachio seeds from Nabeul (98.5% of total glycerolipids).Este estudio tiene como objetivo caracterizar cuatro cultivos de pistacho (Pistacia vera) de Túnez, de las regiones de Mateur (Norte), Nabeul (Nordeste), Kairouan (Centro) y Sfax (Centro-Este) y dos variedades, Mateur and Ohadi, considerando la composición en ácidos grasos y de lípidos mayoritarios (lípidos polares, diglicéridos, triglicéridos y ácidos grasos libres) de semillas maduras. Los lípidos se separaron mediante cromatografía en capa fina, y los ésteres metílicos de los ácidos grasos (FAMEs) se analizaron por cromatografía de gases. El ácido oleico (C18:1 Δ9) fue el mayoritario en todas las muestras; las de la región de Mateur (Norte) fueron significativamente distintas, presentando el contenido más bajo de C18:1 (54.2 % del total de ácidos grasos) y más alto de C18:2 (24.1 %). La cantidad total de ácidos grasos (TFA) en las semillas de la variedad Ohadi fue significativamente más bajo que el de la variedad Mateur de la región de Sfax. Los triglicéridos fueron el componente más importante en la semillas de pistacho de Nabeul (98.5% del total de glicerolípidos)

From insufficient rainfall to livelihoods: understanding the cascade of drought impacts and policy implications

A cascade of drought impacts refers to a series of interconnected events that trigger a chain reaction of effects, extending beyond water scarcity to influence agricultural production, socioeconomic conditions, and the environment. This paper explores the role of society in mitigating drought impacts, particularly through policy responses. Conducting a case study in Ceará State, Northeast Brazil, we used a globally rare dataset of continuous drought monitoring encompassing 3.5 years (February 2019 to October 2022), complemented by interviews with smallholder farmers and agricultural extension technicians. Additionally, we analyzed policy documents related to public policies implemented at the local level. Using a classification of drought impacts as our analytical framework, our findings indicate that social, environmental, and economic impacts of drought are less frequently reported, suggesting that development policies are mitigating cascading effects on livelihoods. Most reported impacts are associated with hydrological drought, revealing the unintended consequences of investments aimed at increasing water supply. We emphasize the significant contribution of public policies in mitigating the cascading effects of drought, which go beyond increasing water availability and focus on strengthening the local economy.</p

Review article: Drought as a continuum – memory effects in interlinked hydrological, ecological, and social systems

Droughts are often long-lasting phenomena, without a distinct start or end and with impacts cascading across sectors and systems, creating long-term legacies. Nevertheless, our current perceptions and management of droughts and their impacts are often event-based, which can limit the effective assessment of drought risks and reduction of drought impacts. Here, we advocate for changing this perspective and viewing drought as a hydrological–ecological–social continuum. We take a systems theory perspective and focus on how “memory” causes feedback and interactions between parts of the interconnected systems at different timescales. We first discuss the characteristics of the drought continuum with a focus on the hydrological, ecological, and social systems separately, and then we study the system of systems. Our analysis is based on a review of the literature and a study of five cases: Chile, the Colorado River basin in the USA, northeast Brazil, Kenya, and the Rhine River basin in northwest Europe. We find that the memories of past dry and wet periods, carried by both bio-physical (e.g. groundwater, vegetation) and social systems (e.g. people, governance), influence how future drought risk manifests. We identify four archetypes of drought dynamics: impact and recovery, slow resilience building, gradual collapse, and high resilience–big shock. The interactions between the hydrological, ecological, and social systems result in systems shifting between these types, which plays out differently in the five case studies. We call for more research on drought preconditions and recovery in different systems, on dynamics cascading between systems and triggering system changes, and on dynamic vulnerability and maladaptation. Additionally, we advocate for more continuous monitoring of drought hazards and impacts, modelling tools that better incorporate memories and adaptation responses, and management strategies that increase societal and institutional memory. This will help us to better deal with the complex hydrological–ecological–social drought continuum and identify effective pathways to adaptation and mitigation.</p

Studies on the antioxidant activity of the essential oil and extract of Tunisian Tetraclinis articulata (Vahl) Mast. (Cupressaceae)

This study analyses the chemical composition and in vitro antioxidant activity of both the essential oil and the 80% aqueous acetone extract of Tetraclinis articulata leaves. The GC-MS analysis of the essential oil identified 66 components that comprise 93.5% of the oil. The major constituents of the oil are: bornyl acetate (31.4%), α-pinène (24.5%) and camphor (20.3%). Antioxidant activities of the samples were determined using four different test systems, namely DPPH, β-carotene/linoleic acid, reducing power and metal chelating activity assay. Test results from the DPPH system showed the strongest radical scavenging activity was exhibited by the 80% aqueous acetone extract (IC(50) = 5.5 µg mL(-1)), which was two times higher than the positive control (BHT). The amount of the total phenolics, flavonoids and condensed tannins was very high in the 80% aqueous acetone extracts. The correlation between the antioxidant activity potential and total phenolic level of the extract was noted

Antioxidant activity of Tunisian Geranium robertianum L. (Geraniaceae)

The present investigation focuses on the methanolic extract obtained from Geranium robertianum L. (Geraniaceae) (Herb Robert), a herbal plant used in traditional medicine for the treatment of human and animal diseases. The antioxidant capacities of the extract were evaluated using 1,1-diphenyl-2- picrylhydrazyl radical, β-carotene/linoleic acid and reducing power and metal chelating activity assays. The amount of total phenolic content, flavonoids and condensed tannins was very high, and the correlation between the antioxidant activity potential and total phenolic level of the extract was pointed out