The Impact of Sea Embankment Reclamation on Greenhouse Gas GHG Fluxes and Stocks in Invasive Spartina alterniflora and Native Phragmites australis Wetland Marshes of East China
The Impact of Sea Embankment Reclamation on Greenhouse Gas GHG Fluxes and Stocks in Invasive Spartina alterniflora and Native Phragmites australis Wetland Marshes of East China
复制标题
围海围垦对华东入侵互花米草和原生芦苇湿地沼泽温室气体温室气体通量和存量的影响
DOI：
10.3390/su132212740
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发表时间：
2021
期刊：
影响因子：
3.9
通讯作者：
Daolin Du
中科院分区：
文献类型：
--
作者：
Jian Li;Zhanrui Leng;Yueming Wu;Guangqian Ren;Guirong Wu;Yongcan Jiang;Taitiya Kenneth Yuguda;Daolin Du
在过去的几十年里，为了限制中国东部沿海湿地的外来C4多年生植物互花米草的扩张，堤坝海堤的引入增加了一倍多。以往的研究主要集中在海堤围垦对盐沼土壤有机碳（C）和氮（N）储量的影响，而没有研究试图评估海堤围垦对盐沼温室气体（GHG）通量的影响。在这里，我们研究了海堤围垦对温室气体存量和通量的入侵互花米草和原生芦苇占主导地位的盐沼在中国江苏省东台湿地的影响。海堤围垦使土壤总有机C和总有机N分别降低了54.0%和73.2%，降低了两种植物沼泽的植物生物量、土壤水分和土壤盐分。在互花米草和芦苇沼泽中，CO2排放量分别增加了38.2%和13.5%，CH 4排放量分别减少了34.5%和37.1%。沿海堤防墙也显着增加了48.9%的芦苇盐沼和减少排放量的17.2%，互花米草沼泽N2 O排放。甲烷CH 4和二氧化碳CO2的通量在恢复和未恢复的部分是相似的，而一氧化二氮N2 O的通量有很大的不同，由于增加硝酸盐作为一个结果N-负载。我们的研究结果表明，海堤围垦显着改变沿海沼泽潜力，特别是在本地芦苇盐沼封存C和N。因此，海堤围垦基本上削弱了本地和入侵盐沼的C和N汇，潜在地耗尽中国沿海湿地的C和N汇。利益相关者和政策制定者可以利用这一科学证据，在海堤填海和沿海湿地入侵植物扩张之间取得平衡。
The introduction of embankment seawalls to limit the expansion of the exotic C4 perennial grass Spartina alteniflora Loisel in eastern China’s coastal wetlands has more than doubled in the past decades. Previous research focused on the impact of sea embankment reclamation on the soil organic carbon (C) and nitrogen (N) stocks in salt marshes, whereas no study attempted to assess the impact of sea embankment reclamation on greenhouse gas (GHG) fluxes in such marshes. Here we examined the impact of sea embankment reclamation on GHG stocks and fluxes of an invasive Spartina alterniflora and native Phragmites australis dominated salt marsh in the Dongtai wetlands of China’s Jiangsu province. Sea embankment reclamation significantly decreased soil total organic C by 54.0% and total organic N by 73.2%, decreasing plant biomass, soil moisture, and soil salinity in both plants’ marsh. It increased CO2 emissions by 38.2% and 13.5%, and reduced CH4 emissions by 34.5% and 37.1%, respectively, in the Spartina alterniflora and Phragmites australis marshes. The coastal embankment wall also significantly increased N2O emission by 48.9% in the Phragmites australis salt marsh and reduced emissions by 17.2% in the Spartina alterniflora marsh. The fluxes of methane CH4 and carbon dioxide CO2 were similar in both restored and unrestored sections, whereas the.fluxes of nitrous oxide N2O were substantially different owing to increased nitrate as a result of N-loading. Our findings show that sea embankment reclamation significantly alters coastal marsh potential to sequester C and N, particularly in native Phragmites australis salt marshes. As a result,.sea embankment reclamation essentially weakens native and invasive saltmarshes’ C and N sinks, potentially depleting C and N sinks in coastal China’s wetlands. Stakeholders and policymakers can utilize this scientific evidence to strike a balance between seawall reclamation and invasive plant.expansion in coastal wetlands.