Urban river wall habitat and vegetation: observations from the River Thames through central London

Abstract

Along heavily engineered urban rivers, river walls and embankments represent the most common habitat available to riparian vegetation. This paper presents the first study into river wall vegetation and the influence of wall surface materials on plant diversity. We were concerned with investigating the plant diversity of such wall habitats, assessing relationships between different wall surface materials and plant diversity, and determining whether river wall and embankment habitats along the River Thames through central London could support native riparian species alongside more typical urban wall flora. Fifteen sites along the River Thames through central London were surveyed to describe wall flora and establish relationships between plant diversity and wall materials. Walls were not species rich, but contained a mix of terrestrial and riparian species. Stone walls with surface fractures and heterogeneous wall surfaces were conducive to plant diversity at the local scale, while wall surface heterogeneity was also important at the landscape scale. Some stratification of vegetation was observed based on wall position relative to flow disturbance. The potential exists for walls to act as sites for habitat improvement and reconciliation ecology within urban rivers.

Inversion of plant dominance–diversity relationships along a latitudinal stress gradient

“…success. Our results supports the importance of plant facilitation as an organizing process in higher-stress environments (Callaway et al 2002, Kawai and Tokeshi 2007, Francis and Hoggart 2009, including communities with transformations in dominance hierarchies, species composition, and disturbance regimes (Bruno 2003, Bruno et al 2005. They also demonstrate how the factors that regulate the response of native plant diversity to invasion can change along stress gradients.…”

The Flora of Urban River Wallscapes

“…Recent studies have investigated more typical urban wall environments and have identified that flora tend to be found at low frequency of occurrence and with low abundance, primarily have ruderal or stress‐tolerating functional strategies, and that different species can associate with wall microhabitats, for example wall bases and wall tops (Gilbert, ; dos Reis et al , ; Lundholm and Marlin, ). These support the observations made by Segal () and more recently quantified by Francis and Hoggart () that wall material, including wall fractures, is important in maintaining certain floral assemblages and plant diversity.…”

Conservation and restoration of marine forests in the Mediterranean Sea and the potential role of Marine Protected Areas

“…Nevertheless restoration actions have been experimented within estuarine habitats [72][73][74][75], coastal urbanized areas [76][77][78], wetlands [79], coral reefs [80], seagrass and eelgrass beds [81,82]. Restoration of kelp and fucoid forests has also been explored in Asia, especially China, Japan and Korea and in North and South America [83][84][85][86][87][88][89][90].…”