作者：Gao, GF; Li, PF; Shen, ZJ; Qin, YY; Zhang, XM; Ghoto, K; Zhu, XY; Zheng, HL

影响因子：4.12

刊物名称：SCIENTIFIC REPORTS

出版年份：2018

卷：8 页码：1-10

Mangroves are critical in global carbon budget while vulnerable to exotic plant invasion. Spartina alternifora, one of typical salt marsh plant grows forcefully along the coast of China, has invaded the native mangrove habitats in Zhangjiang Estuary. However, the efects of S. alternifora invasion on soil carbon gases (CH4 and CO2) emission from mangroves are not fully understood. Accordingly, we conducted a feld experiment to investigate the soil CH4 and CO2 emission during growing seasons in 2016 and 2017 at four adjacent wetlands, namely bare mudfat (Mud), Kandelia obovata (KO), Avicennia marina (AM) and S. alternifora (SA). Potential methane production (PMP), potential methane oxidation (PMO), functional microbial abundance and soil biogeochemical properties were measured simultaneously. Our results indicate that S. alternifora invasion could dramatically increase soil CH4 emissions mainly due to the enhancement in PMP which facilitated by soil EC, MBC, TOC and mcrA gene abundance. Additionally, S. alternifora invasion decreases soil CO2 emission. Both heterotrophic microbial respiration (16S rRNA) and methane oxidation (pmoA and ANME-pmoA) are responsible for CO2 emission reduction. Furthermore, S. alternifora invasion greatly increases GWP by stimulating CH4 emissions. Thus, comparing with mangroves, invasive S. alternifora signifcantly (p<0 .001) increases ch4 emission while reduces co2 emission.

Figure 5. Permutation (number: 9999) test for redundancy analysis (RDA) under reduced model of carbon gases emission, PMP, PMO and functional microbial abundance with enviromental biogeochemical properties. TOC: total organic carbon; EC: electrical conductivity; MBC: microbial biomass carbon; PMO: potential methane oxidation; PMP: potential methane production. Lines in black indicate carbon gases emission. PMO and PMP were presented as green color. Functional microbial abundance was marked as italic and red lines. Soil biogeochemical properties were showed in blue lines with arrows.