Biodiversity conservation in cities: Defining habitat analogs for plant species of conservation interest

Abstract

28Urban plant habitats have become primary drivers of species interactions. They consist of managed 29 vegetation and spontaneous assemblages of native, naturalized, ornamental garden escapes, and invasive 30 species. Our objective was to define urban habitat analogs for a plant species of conservation interest, 31 Matthiola crassifolia, which has persisted in varying abundance in the Mediterranean city of Beirut. 33We adopted a stepwise method that integrates two vegetation assessments, floristics, and physiognomy. We 34 placed seventy-eight quadrats (1m x 1m) in 12 study sites following a deliberate biased method to capture 35 habitat diversity. In every quadrat, we performed taxonomic identification and recorded life form of each 36 species. We pooled species that shared the same life form into categories and estimated area cover for each 37 of these life forms. We performed TWINSPAN analysis on floristic data to identify species positively 38 associated with M. crassifolia, and on life forms, to determine plant assemblages that promote optimal M. 39 crassifolia representation. We then combined findings from both analyses to generate a description of urban 40 habitat analogs suitable for M. crassifolia. 41 42 The results revealed that urban habitat analogs favorable to M. crassifolia include green spaces dominated 43 by palms, low-lying succulents, or by shrubs with scale-like leaves. On the other hand, spaces dominated by 44 turf grass, canopy trees, or vegetation that produces significant litter were not favorable to M. crassifolia's 45 persistence. Based on these findings, we generated a plant palette of native and non-native species to design 46 urban habitat analogs favorable to the persistence of M. crassifolia. 48Synthesis and applications. The application of this method can inform planting designs that yield suitable 49 habitats for plants of conservation interest. It can also guide landscape management plans that seek to create 50 or modify green spaces to optimize growing conditions for species of conservation interest. Depending on 3 51 sites, and based on the information generated by the stepwise method, designers and managers may decide 52 to exclude life forms of native or non-native species that do not support the growth of a species of 53 conservation interest, or they may create an artificial habitat that is conducive to its persistence. 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 72 73 Ornamental, native, naturalized, garden escapes, and invasive plant species, grow in managed, partially 74 managed or unmanaged artificial urban habitats. Native plant species of conservation interest can adapt to 75 such disturbed urban conditions depending on their ruderal behaviors [1]. However, their persistence is 76unlikely as their fate depends on how these artificial habitats are conceived, designed, and managed. This 77 becomes critical when the geographic distribution of a species lies within the boundaries of the city. Urban 78 biodiversity strategies have proposed to transform a...