LAUSR

Abstract The fast growing exotic Sonneratia apetala had been widely used to restore the mangroves in China. Planted mangroves play important roles in enhancing carbon sequestration and nutrient storage. The contents and pools of soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) of simultaneously planted exotic S. apetala and native mixing mangrove (Avicennia marina, accompanied by Aegiceras corniculatum and Kandelia obovata) were quantified to evaluate the ecological restoration effects. Comparing with unvegetated mudflat, the colonization of mangrove can increase the SOC content within 60 cm and total nitrogen contents within 40 cm. No significant differences existed between S. apetala and native mangrove communities for the SOC, TN and TP contents. The restoration of mangrove forests enhanced the soil carbon stock relative to mudflat but significant differences existed only between native mangrove and mudflat. The TN and TP pools were not impacted by the plantation of mangroves. Therefore, plantation of S. apetala less than two decades did not show any advantages on the stocks of organic carbon and nutrients. The mixing native mangrove community should be recommended to enlarge the area of mangrove and enhance the carbon stock capability in the future.