水流條件對苦草及菖蒲磷累積輸運特性的影響

巫丹 凌虹 黃夏銀 周旭 黃畢原

摘 要：采用自主研發的淺水湖泊表面風應力擾動模擬裝置，選擇太湖常風速作為典型動態工況，選用苦草和菖蒲分別作為沉水植物和挺水植物的代表，研究在生長期內水生植物累積輸運磷素的特性對長時間水動力作用的響應過程。結果表明：在擾動風速為5m/s的動態水體中長期生長的苦草，其葉片受到水流脅迫，葉片對磷的吸收和富集受到抑制，植株營養的走向趨于根系儲磷；而動水環境促進了菖蒲的新陳代謝，其葉片對磷的吸收和富集、根部向葉片營養的輸送、根部自身的儲磷能力都得到了提高。

關鍵詞：苦草；菖蒲；水動力；磷

中圖分類號 X5 文獻標識碼 A 文章編號 1007-7731（2018）22-0024-06

Abstract：In this study，an especial equipment was developed to simulate the wind-induced current，Taihu lake was chosen as the research object，Vallisneria natans and Acorus calamus were planted respectively. For Vallisneria natans，based on the long-time hydrodynamic force with the typical velocity in Taihu Lake，the blade growth was restrained，the phosphorus enrichment of leaves were inhibited，the transportation of phosphorus tended to root storage.For Acorus calamus，the dynamic water environment promoted the metabolism，the assimilation and enrichment for phosphorus was promoted，the transportion of phosphorus from root to blade was strengthened，and the store of phosphorus in root was increased. The research results would be beneficial to reveal the environmental function of aquatic plants which provides the theoretical foundation for bio-control of lake eutrophication.

Key words：Vallisneria natans；Acorus calamus；Hydrodynamic；Phosphorus

水生植物是公認的改善水體環境和維持水體清潔的重要工具，其具有調節水體生態系統的物質循環速度，增加水體生物多樣性，抑制藻類過量生長，增強水體穩定性等特點，因而近年來利用水生植物治理污染和進行生態修復，已經得到了廣泛的重視和研究。

水生植物在生長發育及衰亡過程中，通過光合、呼吸、殘體分解等作用改變沉積物——水界面的理化環境進而影響沉積物和上覆水之間磷的遷移轉化。水生植物在生長過程中能通過根及莖葉的吸收，使得上覆水和沉積物中的磷濃度降低[1-3]；但是，處于衰亡的植物的殘體腐爛分解，又將上覆水和沉積物富集的磷釋放到水中，從而引起水質惡化，造成二次污染[4-5]。因此，水生植物的生長狀態決定了水生植物凈化水體的效果。……