Revegetation of subtropical soil slopes: Groundcover performance and the implications of urban development and slope features on plant community

Abstract

Questions: Is revegetation of soil slopes with the currently used plant groundcovers effective in promoting dense vegetation and ecological values of landscapes? Does the degree of urban development influence the abundance of groundcovers? Is there any relationship between slope features and the plant community of soil slopes? Location: Hong Kong Special Administrative Region, China. Methods: We conducted a vegetation study focusing on groundcovers on 35 revegetated soil slopes in urban and suburban areas of Hong Kong and determined differences in plant cover, diversity and community composition among areas under various degrees of development. We also assessed slope features, including presence of erosion control mats, canopy openness, slopes angle, area, elevation and substrate properties, such as soil pH, electrical conductivity (EC) and nutrient status, to examine their relationships to the plant community composition. Results:Plant cover was generally about 30%, with ferns having the highest cover.The initially planted groundcover species were replaced by native graminoids and ferns, or an invasive climbing herb, Wedelia trilobata. Soil slopes covered by erosion control mats had significantly lower plant cover than those without. Contrasting plant community composition of groundcovers was found among areas with different degrees of urban development and between slopes with and without erosion control mats. Slope angle, canopy openness, sandy soil texture and soil EC were closely associated with the plant communities of soil slopes. Conclusions:The current planted groundcovers used for revegetating soil slopes led to unsatisfactory plant cover but allowed colonization of other native groundcovers.Planting strategy using more adaptable native groundcovers, but not invasive species, is a feasible approach to ecologically restore soil slopes. The degree of development and certain slope features influence the plant community and should be considered in the revegetation of soil slopes. K E Y W O R D Secological restoration, erosion control mat, habitat characteristics, hydroseeding, native species | 659

Insight into the Adaptability of Dominant Plant Indigofera amblyantha Craib for Ecological Restoration of Rock Slopes in Stone Coal Mine

“…The eco-restoration was a very effective measure to prevent AMD formation and to green the exposed mine surface [19][20][21]. However, due to lack of the conditions of water, nutrients, and soil layer for plant growth, and with the extreme microclimatic, edaphic conditions, and heavy metals pollution, it was difficult for eco-restoration of exposed rocky slope in the stone coal mine [21][22][23][24][25][26][27]. Cutting and sorting slopes, covering soil, and planting plants were the main methods at present [28][29][30].…”

Estimation of soil mobilization rates by a rainy period and intense tillage practices in vineyards—A case study in the Maule region (Chile)

“…Soil cover is also a determining factor of erosion due to its influence on infiltration (Bradford & Huang, 1994; Chau & Chu, 2018; García‐Díaz et al, 2017). Greater infiltration makes it difficult to generate surface runoff with enough erosive capacity.…”

Root Exudates of <i>Wedelia trilobata</i> Suppress Soil-Borne Pathogenic Fungi and Increase Its Invasion

“…(Asteraceae,), native to tropical America is a representative clonal creeping herb with strong stolons and entomophilous (bisexual) flowers [30,31]. It was first introduced in Hong Kong and in the 1970s in China [32,33]. It was also generally used as a ground cover in South China; however, due to its powerful capacity of expansion, W. trilobata often overgrows into thick ground cover, crowding out and preventing the regeneration of other plant species [34], resulting in the homogenization of the biota in all ecosystems [35].…”