MOLECULAR STRUCTURE OF DISSOLVED ORGANIC MATTER IN MANGROVE SOILS
Keywords:
Dissolved organic carbon, FT-ICR-MS, Molecular composition, Mangrove, Blue carbonAbstract
Mangrove ecosystems act a significant role in climate change adaptation and mitigation strategies. Large quantities of carbon are captured and sequestered in mangrove soils. Dissolved organic matter (DOM) in soils is known as the reactive carbon pool. It is a mixture of heterogeneous organics, involved in biochemical cycles. The molecular composition of DOM encapsulates the key information of carbon transformation and persistence in soils. However, there is still an unknown about the molecular compositions of DOM in mangrove soils. Here, we deciphered molecular constituents of DOM in mangrove soils from China by using the state-of-the-art tool, Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Our study is the first to quantify and qualify soil DOM at molecular levels in mangrove wetlands. We found that DOM molecules in mangrove soils are combined with elements of C, H, O, N, S, and Cl. Soil DOM fates are revealed to be connected to multiple sources coupled with complex reactions in mangrove wetlands. We establish a comprehensive analytical framework of molecular diversity helpful to be extended to apply in other blue carbon ecosystems and provide novel insights into the DOM pool in mangrove wetlands.References
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