Wang Lin, Xie Yangyang, Wang Weiqi, Li Yuan, Hou Ning, Yin Rongbin, Song Zhaoliang, Sardans Jordi, Ge Maoquan, Liao Yiyang, Lai Derrick Y F, Peñuelas Josep
Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, 350117, China; Institute of Geography, Fujian Normal University, Fuzhou, 350117, China.
Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, 350117, China; Institute of Geography, Fujian Normal University, Fuzhou, 350117, China.
Environ Res. 2025 Oct 1;282:122053. doi: 10.1016/j.envres.2025.122053. Epub 2025 Jun 3.
Estuarine wetlands, particularly salt marshes and mangroves, play a critical role as blue carbon ecosystems, yet their mechanisms of carbon sequestration and emission remain poorly understood. Vegetation type significantly influences soil microbial communities and CO dynamics, but comparative studies across wetland types are limited. This study investigates the Minjiang River Estuary wetland to quantify vegetation-driven differences in soil CO emissions and carbon-sequestering functional microbiomes among Phragmites australis (salt marsh), Cyperus malaccensis (salt marsh), and Kandelia obovata (mangrove) wetlands. We conducted a one-year field monitoring campaign, measuring soil physicochemical properties (temperature, pH, electrical conductivity, water content), CO emissions, and microbial communities (cbbL gene sequencing). Temperature sensitivity (Q) of CO emissions was calculated, and microbial networks were analyzed using co-occurrence patterns and random forest modeling. Mangrove (K. obovata) soils exhibited higher pH, moisture, and salinity but 71.5 % lower CO emissions than P. australis wetlands (p < 0.05). Microbial drivers differed by vegetation: Sulfuritortus and Alkalispirillum predicted emissions in salt marshes, while Thioalkalivibrio and Thiobacillus dominated in mangroves (p < 0.05). Specifically, the temperature sensitivity of soil respiration (Q) was significantly higher in mangrove wetlands than in salt marsh wetlands (2.18 vs. 1.28-1.95), indicating greater climate vulnerability. Network analysis revealed mangrove microbiomes were more stable and interconnected, correlating with suppressed emissions. These findings reveal that mangroves demonstrate superior carbon sequestration potential, attributed to distinct microbial consortia and soil properties, thus supporting their prioritization in blue carbon strategies. Crucially, however, their temperature-sensitive CO emissions also highlight a significant vulnerability under warming conditions. This dual insight advances the mechanistic understanding of wetland carbon-climate feedbacks and informs the development of more effective nature-based climate solutions.
河口湿地，尤其是盐沼和红树林，作为蓝碳生态系统发挥着关键作用，但其碳固存和排放机制仍知之甚少。植被类型显著影响土壤微生物群落和二氧化碳动态，但不同湿地类型之间的比较研究有限。本研究调查了闽江河口湿地，以量化芦苇（盐沼）、咸水草（盐沼）和秋茄（红树林）湿地中植被驱动的土壤二氧化碳排放差异以及固碳功能微生物群落。我们开展了为期一年的实地监测活动，测量土壤理化性质（温度、pH值、电导率、含水量）、二氧化碳排放和微生物群落（cbbL基因测序）。计算了二氧化碳排放的温度敏感性（Q），并使用共现模式和随机森林模型分析了微生物网络。红树林（秋茄）土壤的pH值、湿度和盐度较高，但二氧化碳排放量比芦苇湿地低71.5%（p < 0.05）。微生物驱动因素因植被而异：硫杆菌属和嗜碱螺菌属预测盐沼中的排放，而硫代碱弧菌属和硫杆菌属在红树林中占主导地位（p < 0.05）。具体而言，红树林湿地土壤呼吸的温度敏感性（Q）显著高于盐沼湿地（2.18对1.28 - 1.95），表明其对气候的脆弱性更大。网络分析表明，红树林微生物群落更稳定且相互关联，与排放受到抑制相关。这些发现表明，红树林具有卓越的碳固存潜力，这归因于独特的微生物群落和土壤性质，从而支持其在蓝碳战略中的优先地位。然而，至关重要的是，它们对温度敏感的二氧化碳排放也凸显了在气候变暖条件下的重大脆弱性。这一双重见解推进了对湿地碳 - 气候反馈机制的理解，并为制定更有效的基于自然的气候解决方案提供了依据。
