苦草對鹽度脅迫的生理生態響應及其應用

王在易

摘 要：拉尼娜-厄爾尼諾現象交替出現、超強臺風等極端天氣事件屢屢發生，導致我國華南沿海地區受到海水倒灌的嚴重侵襲，鹽度脅迫已成為影響華南河口區沉水植物生長發育及繁殖的主要因素。該文以華南地區最常見的沉水植被“先鋒物種”苦草（Vallisneria natans）為實驗材料，研究其對不同鹽度脅迫的光合生理響應，并通過模擬試驗觀察其表觀生長狀況變化，以期為河口區沉水植被重建與生態修復提供參考。

關鍵詞：苦草；生態生理特性；鹽度脅迫；生態修復

中圖分類號 Q945 文獻標識碼 A 文章編號 1007-7731（2018）21-0021-04

Ecophysiology Responsesof Vallisneria natans to Salinity Stress And Its Application

Wang Zaiyi

（School of Life Sciences and Technology of Jinan University，Guangzhou 510632，China）

Abstract：The alternation of La Nina and El Nino phenomenon，frequent occurrence of extreme weather events such as super typhoons，often seriouslycause alt-water encroachmentinvadethe coastal waters in Southern China，and lead the stress of salinity to become the main factor that affects the estuarine submersed plants'growth，development and reproduction.In this dissertation，the pioneerplant Vallisneria natans in the reconstruction of submerged vegetation were used as experimental materials，to study ecophysiology response of it to differentsalinity stress，andobserve the change of its apparent growth through simulation tests.It might be expected to provides the reference to the submerged vegetation's restoration and ecological restoration in the estuary areas.

Key words：Vallisneria natans；Ecophysiological characteristics；Stress of salinity；Ecological restoration

近年來，超強臺風、海嘯等極端天氣事件頻發，造成我國華南沿海經常性地受到嚴重的海水倒灌，從而引發海岸侵蝕、河口濕地萎縮、沉水植物衰退及生物資源退化等，已經對相關地區的經濟社會和生態環境構成了嚴峻的威脅與挑戰[1]。一方面，海水倒灌使得受影響的沿海地區土壤腐蝕退化和淡水鹽堿化等問題[2]進一步加劇，并引發了咸潮現象，給受侵擾地區的農業、養殖業帶來了困擾，并將大量海洋垃圾卷向海岸、河口、濕地和養殖基塘，造成環境超載、污染嚴重、農業減產、水產品病害盛行等問題，嚴重影響了當地居民的生產生活。另一方面，海水倒灌加劇了河口生態環境的多變性，特別是其直接將等鹽線推向內陸河流，影響范圍向內陸達20km左右[3]，內陸河流鹽分濃度驟升，導致原生沉水植物和浮游植物衰退，引發水生植物群落優勢種群的波動。……