Pattern of Urban Flora in Intra-City Railway Habitats (Alexandria, Egypt): A Conservation Perspective

Intra-city railway areas are deemed large greenspaces and are believed to be key in enhancing the diversity and dynamics of urban flora. In the current study, the floristic composition and diversity along intra-city railway and tram tracks in Alexandria were surveyed. The floristic composition of the plant communities in relation to environmental factors, ecological indicators, and level of human impact was analyzed using multivariate analysis (two-way indicator species analysis (TWINSPAN) for classification and detrended correspondence analysis (DECORANA) for ordination. The multivariate ordination techniques (CCA) revealed differences in the environmental factors and climatic factors influencing the floristic composition of the railway and tram track habitats. Tram tracks suffered higher human impact while maintaining higher vitality and cover compared to train tracks. Species recorded were mainly therophytes, followed by phanerophytes and hemicryptophytes dominated by native species; however, invasive species’ contribution was higher compared to surrounding regions. The number of invasive species was greater in railway areas compared to tram track areas (19 and 15, respectively). The occurrence of two endemic species (Sinapis allionii and Sonchus macrocarpus) with limited national distribution highlights the importance of these habitats as valuable refuge areas for rare and endangered species worthy of conservation action.

Studies of urban flora in Russia: current state and prospects

An overview of Russian literature sources of urban flora studies. The authors analyze the history of urban floral research in Russia and provide definitions of terms – urban flora, native, indigenous, apophytic, alien, synanthropic species. The overview provides a description of methods and approaches used in different studies of urban flora. Special attention is paid to the analysis of the biological diversity of native and alien plants and the features of their spatial distribution in urban habitats. The authors raise problems of protection of biodiversity in cities and show the role of urban protected natural areas. The conclusion of the work outlines the prospects for further study of urban flora. The authors highlight an importance and necessity of creation of a unified database of vascular plants in the urbanized territories of Russia. Further usage of the database will allow to conduct a comparative analysis of the species composition of urban flora and to identify the degree of their homogenization and originality.

Avispas (Insecta: Hymenoptera) asociadas a árboles urbanos de la ciudad de Bogotá, Colombia

Urban trees are a source of food resources, habitat and refuge for the biodiversity that occurs in cities. However, the taxonomic identity and status of each plant species as native and / or exotic of in an ecosystem influences its interactions with biodiversity. Wasps are one of the main insects present in terrestrial ecosystems, including urban ecosystems, as components of their biodiversity, playing an important role as biocontrol agents (predators and parasitoids) of populations of other insects associated with urban flora or as phytophagous. Seeking to deepen into the knowledge of the diversity of wasps in the city of Bogotá and their ecological interactions, in this study the diversity of wasps associated with three native and three exotic species frequently in urban parks of the city was evaluated. In total, 22 wasp families and 227 morphospecies were identified. The families Bethylidae, Chalcididae and Crabronidae are recorded for the first time in Bogotá. On the other part, the families Eulophidae, Ichneumonidae and Braconidae were the ones that contributed with the most richness and abundance in this study. Regarding their association with the evaluated plant species, a greater diversity of morphospecies associated with native tree species was found, however, there is an effect of the taxonomic identity and the factor park on the results that are discussed. It highlighting the importance of conserving the native urban flora in green spaces of Bogota’s city, in order to maintain and preserve the diversity of wasps principally with parasitoid and predator habits and thus enhance their role as natural biocontrol agents of insects that affect the health of urban trees, at the same time that ecological processes and functionality of this urban ecosystem would be stimulated.

Research analysis on urban flora and vegetation in Southeast Europe

In the last two decades, the number of research articles with a focus on urban ecosystems in Europe has increased significantly. However, explored cities are very unevenly distributed, and most of the studies are focused on Central Europe. The aim of this analysis was to provide a realistic insight into the results of previous research on urban flora and vegetation in Southeast Europe. The analysis covers a total of 149 articles, which are classified according to the topic and concept of research. The rates of exploration of urban flora and vegetation vary considerably across the countries of Southeast Europe. The floristic approach was the most common in most of the countries. Although some countries of Southeast Europe have a significant number of floristic studies (e.g. Serbia and Croatia with more than 20 of each country), their urban flora is still insufficiently explored compared to other European regions. Also, the use of different methodologies makes it impossible to compare results in an adequate way and draw relevant conclusions. Unlike the studies in most of Europe, with a broader spatial framework and uniform methodology, in Southeast Europe they usually referred to individual cities, specific habitats or certain parts of the cities. Hence, including Southeast Europe in large-scale studies would be beneficial.