Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia

Temporal and spatial variations of greenhouse gas fluxes from a tidal mangrove wetland in Southeast China

“…Nitrate concentrations were also lower at all study sites (0.37-2.23 mg kg −1 ) as compared to swamps at North Sulawesi (1.54-13.68 mg kg −1 ; Chen et al 2014), Mai Po (0.31-5.29 mg kg −1 ; Chen et al 2012), and South East Queensland (1-25 mg kg −1 ; Allen et al 2007). Despite similarities in nitrate concentrations, the Pear River Estuary in China showed much higher N 2 O fluxes (1.48-251.6 g ha −1 day −1 ) than those reported in this study (Chen et al 2010).…”

“…However, higher CH 4 emissions have been reported in other mangroves, e.g., the fluxes reported for mangrove swamps at Guangdong, China (0.005 to 19.9 kg ha −1 day −1 ) and South East Queensland, Australia (0.001 to 4.18 kg ha −1 day −1 ) are similar to those recorded in the present study (Table 4). In North Sulawesi, Chen et al (2014) showed that despite low CH 4 emissions, sulfate reduction was unlikely to occur as little or no sulfate reduction occurs with a redox potential over −150 mV. Low sulfate reduction rates were also reported at the tropical Ao Nam Bor mangrove in Thailand (Kristensen et al 1994).…”

“…Biological N 2 O is mainly produced by microbial nitrification and denitrification. In mangrove swamps, denitrification is dominant due to the low redox potential in swamp sediments (Chen et al 2014). A study by Zhang et al (2011) revealed the significant impact of S. alterniflora invasion on ammonia oxidizing communities.…”

“…They are highly productive terrestrial ecosystems with high rates of carbon sequestration. While there have been a large number of studies investigating these ecosystems (Alongi et al 2005;Allen et al 2007;Chen et al 2010Chen et al , 2012Chen et al , 2014Dutta et al 2013;Leopold et al 2013Leopold et al , 2015, GHG emissions in this environment remain poorly understood. Mangrove-associated carbon sequestration is currently recognized as a means for ameliorating GHG emissions (Alongi 2014).…”

Effects of enclosure time on the community composition of methanotrophs in the soils of the Inner Mongolia grasslands

“…The major sources of methane include wetlands (Belger et al 2011), rivers (Sawakuchi et al 2014), swamps (Chen et al 2014), rice paddies (Bhatia et al 2011;Liu et al 2012b), and ruminant livestock (Moraes et al 2014). The major sinks of methane are photochemical oxidation by the hydroxyl radical (OH) in the atmosphere (Cicerone and Oremland 1988) and biological oxidation by the methanotrophs in the aerobic soil (Curry 2007).…”