Characteristics and Spatial Influencing Factors of Natural Regeneration within Aquaculture ponds in a Mangrove Forest

Regeneration is an important component of community succession and understanding regeneration dynamics is essential for forest protection and recovery management. Mangroves are distributed along coastlines and this unique habitat has resulted in very different regeneration process. This study took Dongzhaigang mangrove forest in Hainan, China as the study area, considered the 10 years regeneration process in 8 abandoned aquaculture ponds, and the spatial factors that influence the regeneration process are analyzed. The objectives were to: a) investigate the natural dynamics of the mangrove regeneration process in abandoned ponds, b) determine the main spatial factors affecting the natural regeneration process. The results showed that the number of species and individuals showed a tendency to initially rise and then decline, with the maximum occurring at 6–8 years. The results of a diversity index showed an initial rise, with stabilization then occurring over a 8 year period. Aegiceras corniculatum and Sonneratia apetala were typical pioneer mangrove species in the study area, while Bruguiera sexangula and Kandelia obovata were representative species of late regeneration period. Spatial factors, including pond area and shape, relative elevation, distance to a tidal creek and surrounding trees area played important roles in the regeneration of mangrove in ponds. Finally, the study considered the current situation regarding mangrove restoration in China and suggested that natural regeneration of mangroves is a good management option.