ABSTRACT
Asteraceae is the world's richest plant family and is found on all continents, in environments ranging from the coast to the highest mountains. The family shows all growth forms and, as in other angiosperm families, species richness is concentrated in tropical regions. South America has the highest diversity of Asteraceae in the world, yet taxonomic and distributional knowledge gaps remain. This study compiles an updated catalog of Asteraceae native to South America, based on national and regional checklists and ongoing large-scale flora projects. The resulting checklist includes a total of 6,940 species and 564 genera native to South America to date, which represent about a quarter of the family's global diversity. Countries already considered to be megadiverse show the greatest diversity, such as Brazil with 2,095 species, followed by Peru (1,588), Argentina (1,377), and Colombia (1,244), with this diversity mainly focused on the Brazilian Highlands and the Andes. Species endemism also peaks in Brazil, but Sørensen distances reveal the Chilean flora to be eminently different from the rest of the continent. Tribes better represented in the continent are Eupatorieae, Senecioneae and Astereae, also with a remarkably presence of entirely South American subfamilies representing earliest diverging lineages of the Asteraceae, such as Barnadesioideae, Wunderlichioideae, Famatinanthoideae, and Stifftioideae. It is estimated that the discovery and description curves have not yet stabilized, and the number of species is likely to increase by 5 to 10% in the coming years, posing major challenges to continental-scale conservation.
ABSTRACT
The COVID-19 pandemic has had a deep impact on the way we perceive our world. This study explores its effect on Urban Green Space (UGS) perception in Buenos Aires City (CABA), Argentina. We provide a detailed overview of the distribution of UGS in CABA, along with socio-economic analysis and visitors' profile and perception before and during the restrictive measures adopted by the national authorities to contain the COVID-19 outbreak (July to December of 2020). We conducted a series of surveys based on open and closed questions. Before the pandemic, surveys were carried out in situ in eight parks of six districts, randomly chosen. During the confinement, online surveys were conducted. According to our results, the mean UGS density in CABA is 6.09 m2 /person, but marked differences between districts exist, ranging from 0.02 m2 /person to 17.68 m2 /person. This uneven distribution causes differences in the quality of life of CABA inhabitants, perhaps more pronounced during reduced-mobility situations like COVID-19 confinement. Socio economic analysis were done linking multidimensional poverty, COVID-19 positive cases and urban mobility in CABA. Regarding UGS visitors, before the confinement, the majority of respondents were employees or students; during the confinement, employees and retirees predominated. When asked to choose important attributes to describe their perception about the UGS from a given list, respondents selected "calm," "green," and "sounds of nature," without differences before and during the confinement. However, when asked about the UGS role, the main answer was "a place to be with nature" before the confinement and "an important place in the city" during it. Understanding how society perceives the UGS, especially during crises, is essential to rethink the urban landscape and prepare our cities, towards biophilic cities and for a more sustainable future.
