Monospecific Rhizophora spp. trees have been planted for several decades in the Philippines to offset heavy mangrove deforestation resulting mainly from aquaculture pond construction. The reforested mangrove studies are required for evaluating their ecological roles. We surveyed the forest structure, biomass, and net primary production (NPP) at an 18-year-old R. mucronata plantation site (PL) and a secondary natural mangrove site (NM) at Batan Bay Estuary, Philippines. The survey showed that PL had a>8,000 ha^－1 tree density, 351.6 Mg ha^－1 biomass, and 73.2 Mg ha^－1 year^－1 NPP, exceeding the values at NM (670 ha^－1 tree density, 130.7 Mg ha^－1 biomass, and 22.7 Mg ha^－1 year^－1 NPP). The low biomass quantity in NM was due to the residual effects of a typhoon in November 2013; however, the NPP showed a quick recovery which implies the disturbance-adapted characteristics of pioneer species such as Avicennia marina and Sonneratia alba. At PL, the biomass and NPP were large, though it has been known that monospecific Rhizophora spp. plantation has been vulnerable to the risk of stand destruction due to strong typhoons. We concluded that the A. marina and S. alba, which dominated as natural mangrove stand, are suitable for mangrove reforestation because it quick recovered even after the typhoon impacts.

Sustainable land use through rewetting is becoming increasingly important in drained peatlands. We assessed the recovery of productivity of smallholder paludiculture using sago palm (Metroxylon sagu) in a rewetted peatland on Tebing Tinggi Island, Riau Province, Indonesia, which had been drained and burned in 2014. Stand structure and productivity of sago palms in smallholder plantations were measured in December 2016, November 2017, and March 2020. The sago stands were divided into three stands structure groups (pre-harvest stands, mid- to post-harvest stands, and growing period stands) according to gaps in the harvesting cycle, which were distributed in a mosaic pattern. Only those sago palms that had reached their maximum size were harvested, and as a result the mosaic pattern varied over time (spatial variation). The estimated harvest trunk height after rewetting was 8.9±1.5 m (mean±SD), which was not significantly different from that before drainage (9.7±0.4 m). The average annual yield of sago was 26.8 trunks ha^－1, and there was large annual variation. Annual yield of paludiculture conducted after rewetting recovered to the same yield as that before drainage (26.0 trunks ha^－1). Such size distribution patterns and large fluctuations in yield are characteristic of semi-traditional smallholder sago cultivation. Despite fluctuations in annual yield, harvesting only suitable individuals allows sago palms to be supplied every year. The findings obtained in this study will contribute to national and regional efforts to initiate paludiculture using sago palms.