The Habitat and Diversity of Spontaneous Plants in Industrial Wasteland in the Fourth Ring Road of Chengdu

: [Objective] In cities, there is a category of plants given little attention, the so-called spontaneous plants. Although being “indigenous urban inhabitants”, such plants are often seen as targets for removal due to their rough and messy appearance, strong breeding and settlement capabilities, and competitive advantage over cultivated plants. However, in the current context of ecological sustainability, people are gradually realizing that large-scale homogenized landscapes are not the optimal solution for the healthy development of urban ecosystems. It is necessary to explore other beneficial solutions, and spontaneous plants, the inconspicuous “urban weeds”, may be the “key” to such new solutions. Urban industrial wasteland is one of the important habitats for spontaneous plants. Revealing the species composition and diversity characteristics of spontaneous plants in such special habitats may guide the construction of low-maintenance plantscape. [Methods] This research focuses on the central urban area within the Fourth Ring Road (Chengdu Ring Expressway) in Chengdu City, Sichuan Province. The area is divided into the four parts of southeast, northeast, northwest, and southwest parts, based on the lines connecting the four entrances and exits of the Chengdu Ring Expressway to Tianfu Square. Through stratified random sampling, the research determines the potential for reusing wasteland as green space based on land use planning, surrounding water systems, and people’s usage needs. Subsequently, the research selects from within the Fourth Ring Road 10 typical industrial wastelands, including the lands for both light and heavy industries, based on their distribution, size, and industrial type. In total, 584 quadrats are recorded, and the habitat types of spontaneous plants are categorized into four major types: abandoned habitat, semi-hard habitat, wetland habitat, and building habitat. Furthermore, 14 micro-habitat types including spontaneous grassland, spontaneous shrub grassland, and spontaneous underwood are classified