Cyanobacterial crust in Hong Kong and comments on future research

Abstract

The existence of cyanobacterial crust in Hong Kong under both experimental and natural conditions was noted. Thirty0three cyanobacterial species were identified from the soil surface at the site of an erosion experiment. Eleven species were unicellular and 22 filamentous. Fourteen were non-heterocystous and 8 heterocystous cyanobacterial species. None of the species were obligate terrestrial species. Species abundance was measured for one year, and clear seasonal and aseasonal groups of species were established. Macro-environmental data were reported, including soil characteristics, rainfall, rainfall variability and pH, both soil and surface runoff. While the crusts appeared to be fairly stable, except at typhoon intensities, further work is needed to establish degrees of temporal and spatial variation. Non-crust forming cyanobacteria grew on the soil surface under grass and fern. We discuss the future research outlining the potential uses of cyanobacteria in substrate remediation both as an aid to aggregate stability on cut slopes and as a means of accelerating natural plant succession on cut and cement plastered slopes.