Dans des villes toujours plus grandes et plus denses, les espaces à caractère de nature fournissent des services écosystémiques, permettent de conserver la biodiversité et sont des lieux de rencontre entre humains et non-humains. Il est donc essentiel que les décideurs, concepteurs et gestionnaires de la ville puissent rapidement caractériser la biodiversité abritée dans ces espaces afin de concilier ans les projets de développement et les modes de gestion, attentes de la population et enjeux environnementaux. Ici, nous visons à identifier les facteurs déterminant les cortèges d’espèces observés dans les 10 parcs de la ville d’Aix-en-Provence (caractéristiques des parcs, modes de gestion, types de contexte urbain), et ce pour deux taxons aux exigences écologiques différentes : l’avifaune et la chirofaune. Nous avons contacté 39 espèces d’oiseaux. Les communautés aviaires s’homogénéisent de la périphérie vers le centre-ville. On trouve les communautés les plus riches dans les parcs plus grands, présentant une plus grande diversité en habitat et entourés de plus de verdure. Nous avons capté plus de 53 000 passages de chauves-souris, ce qui représente une activité plutôt forte pour des parcs urbains méditerranéens. Il existe une très forte hétérogénéité d’activité entre parcs, qui n’est pas expliquée par les caractéristiques des parcs. Le parc présentant le plus fort taux d’activité est un parc de taille moyenne enchâssé dans de la ville dense. Nos résultats confirment que la question de la biodiversité en ville doit être posée en considérant plusieurs échelles spatiales et plusieurs taxons. La diversité des habitats et la couverture de la végétation dans et autour du parc sont une dimension critique pour l’aménagement et la gestion de la ville.

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Historical texts and archaeological studies attest to the maritime and trade importance of the Persian Gulf since the Sassanid Empires. Nonetheless, there is a paucity of data regarding ancient navigation and the reasons for a shift in m aritim e trade from the western (e.g. Shatt-al-Arab) to eastern (Siraf) Persian Gulf by the Abbasid dynasty. For som e scholars, Siraf was occupied between 360 and 977 CE, after which tim e an earthquake en-trained the dem ise of the city. However, it is unclear when Siraf was founded and how natural navigation conditions changed for ocean-going vessels in harbours of the NW Persian Gulf. To address this knowledge gap, we here present new geoarchaeological data from Siraf. Two anthropogenic facies were detected in drilled cores. They suggest that Siraf dates back to 2 BC-317 CE. After a hiatus, a second occupation phase began during the reign of Shapur II. Relative Sea-Level (RSL) fluctuations, climate change and Persian Gulf bathymetry all affected the possible nautical accessibility of this ancient Persian harbour. A fall in RSL, leading to a shortening of navigable water columns and amplified summertime Shamal wind from 550 CE onwards possibly led to a loss in the im portance of Shatt-al-Arab and other ports in the western Persian Gulf. It appears to have m ade Siraf the best alternative for seafarers. According to the wind regimes, the best time for arrival and departure from Siraf was August and October, respectively. RSL rise and increasing coastal erosion during the winter-tim e Shamal winds led to the degradation of harbour potentialities and was possibly at the origin of econom ic decline and poorly adapted harbour works at Siraf during a 150-year period between 850 and 1000 CE.

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Mediterranean island biodiversity is threatened by invasive plants, especially by Carpobrotus species. Invasive plant control is a major management tool for the restoration of invaded areas, but the effect of Carpobrotus removal on arthropods is poorly understood. In this study, we evaluate how spider assemblages are influenced by Carpobrotus removal on a Mediterranean island. A Carpobrotus patch was manually uprooted, followed by litter removal between November 2011 and February 2012. A nearby site with native matorral vegetation and no management was also studied. Spider communities were sampled using pitfall traps two years before removal (2010–2011), and then every two years after, between 2013 and 2019. Vegetation at the Carpobrotus site changed from a dense mat of Carpobrotus to a diverse halophilous grassland with some chamaephytes, while it remained stable in the matorral. Spider species richness increased significantly after removal and significant changes in assemblage composition were observed between pre- and post-removal years with a high turnover rate, while spider assemblages remained relatively stable in the matorral. Litter-dwelling spiders with trap strategies like Oecobius navus were the most reduced by Carpobrotus removal, while foliage-dwelling spiders which forage on plants like Xysticus benefited the most, likely due to vegetation opening and diversification of microhabitats. The increase in bare ground cover favoured Aelurillus v-insignatus, Nomisia celerima and Zodarion elegans, which are characterized by an affinity for dry sunny environments. Invasive Carpobrotus removal induced a rapid change (7 years) in spider assemblages as well as an enrichment in taxonomic and functional diversities.

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