DOI: 10.5061/dryad.tqjq2bw85
title: Spatial distribution and driving factors of microbial necromass carbon in coastal wetlands of China

description: Microbial necromass carbon (MNC) constitutes a vital component of soil
 carbon pools and is integral to the global soil carbon cycle. However, the
 mechanisms driving MNC accumulation in large-scale coastal wetlands,
 particularly across different habitat types (such as mangroves,
 saltmarshes, and mudflats), remain poorly understood. In this study, we
 conducted extensive sampling across 101 sites in China's coastal
 wetlands, covering a latitudinal gradient of over 2,500 km, to investigate
 variations in MNC and its drivers. Additionally, we integrated global data
 from farmland, forest, grassland, and coastal wetland habitats for a
 comparative analysis to explore the specificity of carbon storage
 mechanisms in coastal wetlands. Our results reveal significant differences
 in MNC content among the three coastal wetland habitats, with mangroves
 exhibiting the highest MNC levels and saltmarshes the lowest. We found
 that primary productivity, especially plant biomass, is the dominant
 driver of MNC accumulation in coastal wetlands, while climatic factors
 have an indirect effect. Furthermore, after accounting for the influence
 of plant biomass, we observed that edaphic properties also played an
 important role in driving MNC accumulation within mudflat and saltmarsh
 habitat. Compared to other habitats, i.e., grasslands, forests, and
 farmlands, coastal wetlands exhibited lower MNC levels (8.44 mg/g) and a
 reduced contribution to soil organic carbon (32.16%). In conclusion, these
 findings demonstrate that plant primary productivity significantly
 regulates MNC accumulation in coastal wetlands. Furthermore, coastal
 wetlands exhibit distinct characteristics in carbon storage compared to
 other ecosystems, underscoring the unique role of blue carbon ecosystems
 in the soil carbon cycle.
description: Soil samples were sampled from 101 sampling sites in Binhai,
 China. The hydrolysates of the collected soil samples were centrifuged,
 neutralized, and then centrifuged at 4000 rpm for 10 min. The supernatant
 was freeze-dried, purified with anhydrous methanol, derivatized with
 derivatization reagents, and extracted with dichloromethane. The organic
 phase containing the aminosugar derivative was dried with Nitrogen at 45°C
 and redissolved in a 1:1 solvent of hexane and ethyl acetate. We
 quantified the concentrations of GluN, mannosamine (ManN), galactosamine
 (GalN), and MurA using an Agilent 6890A gas chromatograph/mass
 spectrometer and a DB-5 capillary column (30 m × 0.25 mm × 0.25 μm) with
 myo-inositol as an internal standard.
description: # Spatial distribution and driving factors of microbial necromass carbon
 in coastal wetlands of China
 [https://doi.org/10.5061/dryad.tqjq2bw85](https://doi.org/10.5061/dryad.tqjq2bw85) ## Description of the data and file structure ### Files and variables #### File: Microbial\_necromass\_carbon\_dataset\_for\_coastal\_wetlands\_in\_china.xlsx Data table of microbial necromass carbon in coastal wetlands across China ##### Variables * "FNC": Fungal Necromass Carbon * "BNC": Bacterial Necromass Carbon * "MNC": Microbial Necromass Carbon #### File: Global\_literature\_synthesis\_data\_on\_Microbial\_necromass\_carbon\_and\_Microbial\_necromass\_carbon\_contribution\_to\_Soil\_Organic\_carbon.csv This dataset compiles results from a global literature synthesis on microbial necromass carbon (MNC) and its contribution to soil organic carbon (SOC). ##### Variables * "No": Number * “Citation”: Literature Citations * “Latitude“ & “Longitude”: The longitude and latitude of the Literature data * “Ecosystem”: Ecosystem Type * "Glucosamine": Glucosamine, a type of amino sugar * "Muramic acid": Muramic acid, a type of amino sugar * "Soil C": Soil Organic Carbon * "MNC":  Microbial Necromass Carbon * "MNC_SOC": Ratio of microbial necromass carbon to soil organic carbon ##### Note on Missing Information * Some bibliographic fields or metadata entries (e.g., longitude and latitude, glucosamine, muramic acid, soil organic carbon) may be missing. * In such cases, the value **"n/a"** is used to indicate that the data is **not available**.