Abstract：
To elucidate the spatial-temporal impact of invasive saltmarsh plant Spartina anglica on the biogeochemical processes in coastal wetlands, we investigated the rates and partitioning of organic carbon (Corg) mineralization in three representative benthic habitats: (1) vegetated sediments inhabited by invasive S. anglica (SA); vegetated sediments by indigenous Suaeda japonica; and (3) unvegetated mud flats. Microbial metabolic rates were greatly stimulated at the SA site during the active growing seasons of Spartina, indicating that a substantial amount of organic substrates was supplied from the high below-ground biomass of Spartina. At the SA site, sulfate reduction dominated the Corg mineralization pathways during the plant growing season, whereas iron reduction dominated during the non-growing season. Overall, due to its greater biomass and longer growing season than native Suaeda, the expansion of invasive Spartina is likely to greatly alter the Corg-Fe-S cycles and carbon storage capacity in the coastal wetlands.
摘要：
为了阐明入侵的盐沼植物Spartinaanglica对沿海湿地生物地球化学过程的时空影响，我们调查了三个代表性底栖生境中有机碳（Corg）矿化的速率和分配：（1）由入侵的S.anglica（SA）居住的植被沉积物；土著碱蓬的植被沉积物；（3）无植被的泥滩。在Spartina活跃的生长季节，SA部位的微生物代谢率受到了极大的刺激，这表明大量的有机底物是由Spartina的高地下生物量提供的。在SA现场，硫酸盐还原在植物生长季节主导了Corg矿化途径，而铁还原在非生长季节占主导地位。总的来说,由于其生物量更大，生长季节比原生基地基地长，侵入性天草的扩张可能会极大地改变沿海湿地的Corg-Fe-S循环和碳储存能力。
