This study is the first ethnobotanical survey focusing on the herbal medicines traditionally used by the nomadic community of the Algerian steppe, identifying new medicinal plants and uses from one of the most characteristic indigenous populations in Algeria. Moreover, the study contributes to the understanding of transmission of medicinal plant knowledge in the Mediterranean basin. This work aims to document the phytotherapeutical knowledge and practice of the nomadic community of the Algerian steppe, and compare it with neighbouring sedentary populations and Mediterranean historical texts. Through this, the study strives to evaluate processes of transmission of knowledge among this population, for whom written sources have been largely unavailable. Ethnobotanical surveys were carried out during two years (2015-2017). In total, 73 informants from nomadic populations were interviewed in several steppe regions including areas in the administrative departments of Tiaret, Saida, Naama, Djelfa and M'sila. Structured interviews about medicinal plant knowledge were combined with guided tours with the informants. Prior informed consent was always obtained. The surveys allowed for the collection of sociodemographic data and traditional knowledge about medicinal plants and their uses. Informant Consensus Factor (FIC) was calculated to evaluate agreement among informants. Results were compared to existing literature to evaluate similarities between this nomadic medicinal flora, that of neighbouring communities and historical texts and identify new plant citations and uses. Among Algerian nomadic communities, herbal remedies are used mostly by women and elders, who are often illiterate. We identified 97 taxa of medicinal plants belonging to 42 botanical families, importantly Lamiaceae, Asteraceae and Apiaceae, like in neighbouring communities. The most common plant parts and method of preparation are also shared with neighbouring populations. New uses are described for 25 known medicinal taxa, and nine species with undocumented medicinal uses in recent literature have been reported. However, some of these have been reported in Mediterranean materia medica. In total, 60% of the medicinal plant diversity used by Algerian nomads are well-known plants of the Mediterranean ethnopharmacological heritage. This study highlights the importance of traditional medicine for Algerian nomad communities. This indigenous population has specific knowledge about plants from their steppe environment, but also shares a pool of knowledge with sedentary Algerian populations and Mediterranean people as a whole. Our research shows that a common North African and Mediterranean ethnobotanical heritage exists.

Résumé Cette recherche est une approche ethnobotanique descriptive et analytique, qui a pour objectif l’analyse floristique (biologie et chorologie), phytothérapeutique (usages et maladies traitées) et taxonomique (identification et description botanique) de l’inventaire des plantes médicinales du massif de Guezoul situé à l’extrémité nord de la ville de Tiaret. Les relevés phytoécologiques que nous avons réalisés récemment dans la région nous ont servi de base de données pour cet inventaire. La sélection des espèces aux fins médicinales ainsi que les indications thérapeutiques ont été effectuées à l’aide d’une enquête ethnobotanique réalisée essentiellement auprès de la population locale, ainsi que des quelques herboristes et guérisseurs de la région. Nous avons aussi utilisé différents documents bibliographiques à titre comparatif. Cela nous a permis de distinguer 66 espèces que nous qualifions de plantes médicinales. Parmi ces espèces, 60 sont indiquées dans notre enquête, les autres espèces ne sont citées que dans la littérature et semblent méconnues dans la région. Ces plantes, essentiellement méditerranéennes, relèvent de près de 39 familles botaniques différentes dominées par les Orchidaceae et les Lamiaceae aromatiques riches en huiles essentielles. Elles sont surtout employées dans les traitements de l’appareil digestif, les pathologies internes (diabète, foie, etc.) et de l’appareil urinaire. Aussi, nous relevons dans cette étude quelques précisions taxonomiques sur certaines plantes médicinales, en affinant l’identification botanique avec quatre sous-espèces identifiées. Enfin, nous proposons trois nouveaux taxons pour la flore médicinale en Algérie qui sont: Thymus munbyanus Boiss. & Reut. subsp. munbyanus, Allium roseum L. subsp. roseum et Evernia prunastri (L.) Ach.

A floristic, ethnobotanical and natural habitat study was carried out in the wetlands of the Macta marshes in northwest Algeria. The specimens obtained made it possible to identify 89 taxa of plants belonging to 32 botanical families dominated by the Amaranthaceae and Asteraceae. Analysis of the chorology of the plants has shown dominance of the Mediterranean element, but only 3 endemic taxa are recognized. Five of the taxa are considered rare and 4 are protected in Algeria; 5 have an IUCN status of minor consideration and Spergularia doumerguei P. Monnier has the status of vulnerable. Analysis of local plant communities has shown the existence of 6 plant groups within 3 types of natural habitats that have been mapped. The ethnobotanical study carried out on 100 inhabitants of the study area made it possible to recognize 73 useful plants of which 69 are used for medicinal purposes.

Ethnoveterinary medicine is vastly under-documented, especially in North Africa, where livestock care is increasingly medicalised. Despite evidence of the interdependence of ethnoveterinary practices and ethnomedicine for human care, the overlap between these two systems and the possible drivers of similarity are rarely addressed in ethnopharmacological literature. Here, we present the first quantitative comparison of remedies used to treat human and animal health among a pastoral society. This study aims to document the plants and other materials used in ethnoveterinary medicine among nomadic herders in the Algerian steppe. We calculate the overlap with remedies used for human health and evaluate some of the possible drivers of similarities between the two interlinked medical systems. The field study was conducted in spring 2018 with 201 local knowledge holders in five provinces in the central part of the Algerian steppe. Forty-six camps and ten weekly animal markets were visited. After obtaining prior informed consent, data was collected through structured interviews. Anonymous sociodemographic information was collected along with veterinary use data. Plant specimens were acquired, identified and deposited in the Botanical Laboratory Herbarium of the University of Tiaret. Ethnobotanical information was structured in use reports and therapeutic applications organised into 13 simple categories. Plants used in ethnoveterinary medicine were compared to those used in human health care using a Chi square test, and ethnoveterinary use was predicted using a generalised linear model with use for human care and plant family as predictive variables. Logistic regressions were also used to test if any specific medicinal application predicts shared use in human and veterinary medicine. Sixty-six plant species from 32 botanical families and ten non-vegetable remedies were documented. Plants from the Lamiaceae, Asteraceae, Fabaceae and Apiaceae families were most commonly used. The plants most often cited by interviewees are all harvested from the wild (Echinops spinosissimus Turra, Atriplex halimus L., Artemisia campestris L., Juniperus phoenicea L. and Peganum harmala L.). Leaves are the most commonly used plant part and decoction is the most common preparation method. There are important similarities between remedies used to treat humans and other animals: two thirds of the remedies used in ethnoveterinary medicine are also used in human health care, and these represent half of the human health treatments. Use for human health and plant family both predict the use of a medicinal plant in veterinary medicine, but no correlation is found regarding specific therapeutic applications. Traditional veterinary knowledge is still key to sheep and goat herders in the Algerian steppe, but a knowledge transmission gap seems to exist between older and younger generations, and ethnoveterinary practices may disappear in the near future. Treatments for human and animal care overlap to a large extent, and a causal relationship possibly exists for, at least, some of them. However, overall a smaller number of remedies are used to treat animals than humans and for less therapeutic applications. This difference in the diversity of therapeutic applications and remedies should be the object of future research.