Species Diversity, Color Quantification, And Light Adaptation of Plants with Red or Purple Abaxial Leaves in Urban Green Spaces of Shenzhen

Abstract

To clarify the species composition, color attributes, and application characteristics of plants with red/purple abaxial leaves in urban green spaces, park green spaces, campus green spaces, and residential green spaces in Shenzhen were surveyed. The NCS-1950 color chart was used to quantify the abaxial leaf color of the recorded plants, and photosynthetically active radiation (PAR) and soil plant analysis development (SPAD) values were measured. A total of 41 species (including infraspecific taxa) with red/purple abaxial leaves were recorded, belonging to 12 families. Among them, Marantaceae had 11 species, Begoniaceae 14 species, Commelinaceae 4 species, Araceae 2 species, Acanthaceae 2 species and Asteraceae 2 species; the remaining species belonged to Euphorbiaceae, Zingiberaceae, Saxifragaceae, Lamiaceae, Musaceae, and Gesneriaceae. Abaxial NCS hues were mainly concentrated in the R–R50B interval, dominated by red and red-purple series, with an obvious gap in the blue-purple series. The largest numbers of plots were recorded for Excoecaria cochinchinensis, Tradescantia spathacea, and Marantaceae species. Begoniaceae was the most species-rich family but was concentrated under park canopies. Excoecaria cochinchinensis was the most sensitive to light environment changes and can serve as a candidate indicator species; Marantaceae and Begoniaceae had strong shade tolerance and are suitable for low-light environment configurations.