Please use this identifier to cite or link to this item:
Distribution and Magnitude of Nitrogen and Phosphorus Limitation of Autotrophic Microplankton in the East China Sea---Multiple Detection Using Gene Expression, Phosphatase Activity, and Chlorophyll Fluorescence
|Contributors: ||NTOU:Institute of Marine Biology|
East China Sea;phytoplankton;nutrient limitation;marker genes;alkaline phosphatase;nutrient-induced fluorescence
|Issue Date: ||2011-06-28T07:02:07Z
|Abstract: ||摘要:東海是臺灣附近的陸棚海域，不但提供了豐富的漁業資源，而且是移除大氣中二氧化碳的場所。由於這兩個過程都和微型浮游植物 (指體型大於20 μm的單細胞藻類)息息相關，探討微型浮游植物生長如何受到氮或磷營養鹽的限制是瞭解東海食物鍊能量傳輸與生態系碳循環的必要資訊。有鑑於此，本計畫擬利用三年的時間，以多種相互獨立的技術，定義東海中氮與磷限制微型浮游植物生長的區域。這些技術包括營養鹽添加的培養實驗、氮磷缺乏之指標基因表現量的偵測、使用鹼性磷酸脢活性評估磷限制的強度、以及用誘發螢光判斷氮磷缺乏對光合作用之影響等等，這種以各種技術相互支援的策略應能以更確定的方式顯示出微型浮游植物的生理狀態。本計畫不僅將新的觀念和技術帶入海洋生態與漁業的領域，而且在東海面臨氣候暖化與三峽大壩截流之雙重衝擊下更顯得刻不容緩。|
Abstract:The goal of this research project is to investigate how the growth of autotrophic microplankton (body sizes > 20 µm) is controlled by nitrogen and phosphorus in the East China Sea. Based on this information, a better understanding of energy transfer along the food chain and carbon cycling within the ecosystem can be achieved. Since there is no prefect method in detecting nutrient stress in phytoplankton, several independent methods were used in parallel to define nitrogen-stressed and phosphorus-stressed regions for microphytoplankton in the East China Sea. These methods included nutrient enrichment incubations, the expression of marker genes related to nitrogen- and phosphorus-stress, alkaline phosphatase activity measurement for the determination of phosphorus limitation, and nutrient-induced fluorescence analysis to determine the influence of nutrient limitation on photosynthesis. During the first year of this project, an oceanographic cruise was conducted to the East China Sea. Alkaline phosphatase activity and nutrient-induced fluorescence were measured for microphytoplankton, and a combined analysis revealed that phosphorus stress of microphytoplankton mainly occurred in 2 areas. One located in the northern East China Sea beyond the Changjiang river plume, and the other located in the southern East China Sea near the entrance of Taiwan Strait. The formation of these phosphorus-stressed regions can be explained by hydrographic dynamics. In addition, the sequence diversity of a nitrogen stress indicator gene, Nrt2, was examined in the East China Sea. This result will be helpful to the design of polymerase chain reaction primers in the future. The relationship between nitrogen stress and Nrt2 expression was also studies, and a research paper based on this result was published in an academic journal. In the following year, the same strategy will continuously be employed to evaluate the physiological status of micro- phytoplankton, and the relationship between physiological status and environmental changes will be examined.
|Appears in Collections:||[海洋生物研究所] 研究計畫|
Files in This Item:
There are no files associated with this item.
All items in NTOUR are protected by copyright, with all rights reserved.