Urban green spaces as tardigrade biodiversity hotspots in Salta city (Argentina)

ANDREA X, GONZÁLEZ REYES; GRABOSKY, A; SANDRA RODRIGUEZ ARTIGAS; BALLARDINI F; FERNANDEZ D.; OSTERTAG, B; MEIER MF; ROCHA, ALEJANDRA MARIANA; CORRONCA JA

Simposio; 15th International Symposium on Tardigrada; 2022

Background: In urban landscapes, fragmentation is widely regarded as a major threat tobiodiversity, as it significantly alters landscape structure and decreases landscape connectivity.As a result, fragmentation restricts the dispersal of many species as well as the formation ofstrongly structured metacommunities. In Salta, Argentina, we tested the hypothesis that urbangreen spaces function like tardigrade biodiversity hotspots.Methods: A total of 36 samples were collected. Green Areas (GA) and three neighbouringurban habitats were sampled: high (H), medium (M), and low (L) vehicular traffic. Specimenswere handled following the normal research protocols. PAST, PC-Ord, iNEXT, SPADE, and Rwere used to analyse the data.Results: Were collected 2380 specimens, representing 14 species/morphospecies. Green Areaswas 1.20, 1.63, and 1.67 times more diverse than the L, H, and M communities, respectively.The GA community was more equitable, with a wider range of guilds. However, three speciesdominated the urban communities: Macrobiotus sp. nov, Milnesium quiranae, and Viridiscusrufoviridis. The partition of beta diversity revealed a species turnover gradient from GA to M.GA and L communities had the highest turnover (68%), whereas the difference in assemblagecomposition between GA and H was attributed to both components: species turnover (48%)and nesting (52%). The DCA analysis revealed a nested pattern between tardigrade assemblagesin disturbed habitats and urban green spaces, with the first axis explaining 69.3% of the totalvariation observed and the second axis being despicable (8%). The Mantel test revealed thatgeographical distance between sites might explain some of the variations in assemblagesimilarity (R = 0.3406, p = 0.0262). As a result, urban sites closer to green spaces share morespecies than those farther away.Conclusions: We found that green spaces in Salta city have a higher diversity of tardigrades,but urban communities have a propensity to establish a general nested pattern and a loss ofspecies, resulting in biotic homogeneity in urban areas. Despite this, urban green spaces canact as biodiversity hotspots by supplying species to the urban areas nearby