| 摘要: |
| 互花米草作为黄河三角洲外来入侵物种，2010年开始爆发式蔓延，2020年面积最大时可超6000公顷，对潮间带生物多样性造成了严重影响。自2020年起，黄河三角洲自然保护区开始大规模的互花米草整治与盐地碱蓬生态修复工作。互花米草具有较强的消浪、缓流、促淤、固滩能力，短期内、大范围的植被去除，可能导致波流和沉积动力环境的突变。基于现场观测数据和考虑植被作用的浪、流、沙耦合数值模型，研究分析了互花米草整治和盐地碱蓬修复对黄河三角洲湿地动力过程的影响，重点关注风暴作用下黄河三角洲潮滩湿地的防灾减灾能力和沉积效应变化。研究结果表明，互花米草可有效抵御极端风暴潮，最大风暴潮位衰减率可达15 cm/km。互花米草整治将导致湿地防灾减灾能力显著下降，堤前风暴潮峰值可抬升10-30 cm，同时潮间带的泥沙捕集能力大幅下降。受限于植被密度、高度，盐地碱蓬完全修复后湿地衰减风暴潮、捕集泥沙的能力显著低于原互花米草湿地。研究建议，互花米草整治工程应考虑短期内植被去除导致的近岸风暴潮抬升、侵蚀加剧等潜在风险。 |
| 关键词: 黄河三角洲 盐沼 互花米草 湿地整治 风暴潮 |
| DOI：10.11693/hyhz20230400087 |
| 分类号: |
| 基金项目:国家重点基础研究发展计划（2022YFC3204301-4）”长江黄河等重点流域水资源与水环境综合治理“；国家自然科学基金项目（52071305）“极端风暴潮及其在滨海湿地中的衰减机制研究” |
附件 |
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| Effects of Spartina Alterniflora Removal on Storm Surge Attenuation and Sediment Trapping in the Intertidal Zone of the Yellow River Delta |
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gaoxiang1, wangkemeng1, Wu Guoxiang2, liangbingchen3,1, zhangshuyan4
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1.College of Engineering, Ocean University of China, Qingdao, Shandong;2.Ocean University of China;3.Key Laboratory of Ocean Engineering of Shandong Province, Ocean University of China, Qingdao;4.Yellow River Mouth Management Station of Shandong Yellow River Delta National Nature Reserve, Dongying
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| Abstract: |
| Invasive species Spartina alterniflora have dramatically spread in the Yellow River Delta since 2010. The maximum area of Spartina alterniflora reached 6000 hectares in 2020, exerting a great negative effect on the intertidal biodiversity. Comprehensive regulations have been conducted in the Yellow River Delta National Nature Reserve including Spartina alterniflora removal and Suaeda salsa restoration since 2020. The large-scale vegetation removal within a short time caused significant changes in the hydrodynamics and morphodynamics of the intertidal wetlands. In this study, this effect was studied based on field measurements and a process-based model coupling hydrodynamic and morphodynamic processes, specifically on the storm surge attenuation and sediment trapping capacity. We show that maximum storm surge attenuation rate exceeded 15 cm/km when Spartina alterniflora was present, and maximum water level would increase by 10-30 cm after vegetation removal. Additionally, Spartina alterniflora are pivotal to marsh sedimentation and the regulations will decelerate the sediment trapping efficiency in the intertidal flat. Limited by stem density and height, local Suaeda salsa are less effective in attenuating storm surges and trapping fine sediments compared to the Spartina alterniflora. This study provides evidence that rapid vegetation removal may put the intertidal zone to risks of extreme water levels and may stimulate serve erosions. We appeal that integrated assessment and proper restoration strategies should be conducted for wetlands regulations. |
| Key words: Yellow River Delta salt marsh Spartina alterniflora wetland restoration storm surge |