Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, 221 Burwood Hwy, VIC 3125, Australia.
Mar Pollut Bull. 2021 Apr;165:112024. doi: 10.1016/j.marpolbul.2021.112024. Epub 2021 Feb 5.
Coastal ecosystems are under increasing pressure from land-derived eutrophication in most developed coastlines worldwide. Here, we tested for 277 days the effects of a nutrient pulse on blue carbon retention and cycling within an Australian temperate coastal system. After 56 days of exposure, saltmarsh and mangrove plots subject to a high-nutrient treatment (~20 g N m yr and ~2 g P m yr) had ~23% lower superficial soil carbon stocks. Mangrove plots also experienced a ~33% reduction in the microbe Amplicon Sequence Variant richness and a shift in community structure linked to elevated ammonium concentrations. Live plant cover, tea litter decomposition, and soil carbon fluxes (CO and CH) were not significantly affected by the pulse. Before the end of the experiment, soil carbon- and nitrogen-cycling had returned to control levels, highlighting the significant but short-lived impact that a nutrient pulse can have on the carbon sink capacity of coastal wetlands.
在世界上大多数发达的海岸线地区，沿海生态系统正承受着来自陆地的富营养化的日益增加的压力。在这里，我们测试了 277 天内营养物质脉冲对澳大利亚温带沿海系统内蓝碳保留和循环的影响。经过 56 天的暴露，接受高营养处理（20 g N m yr 和2 g P m yr）的盐沼和红树林样地的表层土壤碳储量降低了约 23%。红树林样地的微生物扩增子序列变异丰富度也降低了约 33%，这与铵浓度升高导致的群落结构变化有关。活植物覆盖、茶渣分解和土壤碳通量（CO 和 CH）未受到脉冲的显著影响。在实验结束前，土壤碳氮循环已恢复到对照水平，这突显了营养物质脉冲对沿海湿地碳汇能力的显著但短暂的影响。
