Can Benggang be regarded as gully erosion?

The most dominant fragmented erosional landform, usually termed as "Benggang" or "Collapsing gully", has been highlighted as a national concern in China due to its serious impacts on ecosystem and social services in tropical and subtropical regions. To facilitate the investigation and prevention of Benggang, a comparative study relating to Benggang and similar erosional landforms around the world has been made by reviewing the relevant research. According to its definition, threshold-dependent process, and geomorphological character, Benggang could be regarded as a large-scale gully. The formation and development of such gully are determined by thickness of the weathering mantle. Specifically, the subtropical-tropical climatic condition accelerates weathering process and provides erosion force, while the appropriate lithology and geomorphology determine the formation and distribution of the thick weathering mantle. In general, the driving forces and formation mechanisms of gullies with regional characteristics around the world are determined by the spatial variation of soil, lithologic and environmental conditions. In order to highlight soil erosion in southern China and promote the establishment of a global research network of gully erosion, it would be better to regard Benggang as a specific large-scale gully instead of a unique erosion type in a global perspective. Futhermorer, to tackle this urgent environmental problem, it is necessary to continue efforts for a better understanding of the erosion mechanisms and implementations of effective control of Benggang. This study would facilitate the investigation and preventation of Benggang, and benefit the promotion of ecosystem services and functions in southern China.