打鳥埤人工濕地CO_2通量推估及四季變化趨勢

To Evaluate CO_2 Flux and Its Seasonal Tendency on Daniaopi Constructed Wetland

藍詠耀(Yung-Yao Lan) ； 張詠翔(Yung-Hsiang Chang) ； 莊秉潔(Ben-Jei Tsuang) ； 林煜棋(Yu-Chi Lin) ； 陳思為(Sih-Wei Chen) ； 陳勇達(Yung-Da Chen) ； 王奕智(Yi-Chih Wang) ； 杜佳穎(Chia-Ying Tu)

《濕地學刊》 1卷1期 (2012/01) Pp. 21-31

https://doi.org/10.30124/JW.201201.0003

摘要

濕地是生物生產力最旺盛的生態系統，濕地中的水生及陸生植物進行光合作用並吸收大氣二氧化碳形成有機碳積蓄於濕地中，因此濕地與森林一樣都為地球碳物質循環的重要儲存場所。本研究利用渦流協變系統（Eddy Covariance Method, EC）直接量測人工濕地的溫室效應氣體濃度、水氣及CO_2通量和能量通量等。由結果顯示2008年打鳥埤濕地完成第一年整個碳通量呈現釋放現象，通量為0.762 kg C m^(-2) yr^(-1)，CO_2濃度為392.15 ppm；2009年濕地趨於穩定狀態呈現吸收之現象，通量為-0.023 kg C m^(-2) yr^(-1)，CO_2 濃度為414.18 ppm；2010上半年維持吸收現象，預估通量可達-0.537 kg C m^(-2) yr^(-1)，CO_2 濃度為413.68 ppm。配合國科會濕地碳通量與蓄存總計劃及其他子計畫生態系統的調查及氮磷生地化循環之研究，2008到2010年共進行了七次打鳥埤濕地的碳觀測，實驗的主要目的在於瞭解人工濕地在不同時期和不同處理單元之下，CO_2（碳）通量的吸收或釋放現象，從分析結果，（1）春季時，第一密植區與第二密植區呈現吸收的現象，第一密植區略大於第二密植區；（2）夏季時，第一密植區、第二密植區與生態池均呈現吸收之現象，第一密植區大於第二密植區與生態池，而沉澱池為強烈釋放之情形；（3）秋季時，開放水域呈現釋放的現象；（4）冬季時，沉澱池均為排放之現象，而第二密植區與生態池為微弱吸收現象。整體而言，除了沉澱池為釋放現象外，整個濕地環境多呈吸收之現象。以各處理單元來討論，沉澱池白天仍為微弱吸收現象，而晚上呈現劇烈釋放情形，推測有多種有機生物作用，使得沉澱池為碳放源；而第一密植區為最強的碳吸收源，較第二密植區與生態池強，其原因需探討各池中植物生長及澡類微生物之生態系來做判斷；第二密植區也為碳吸收源，其以各季節之影響較小，而第一密植區與第二密植區為打鳥埤濕地各處理單元中主要的碳吸收源。

關鍵字

CO_2通量 ； 打鳥埤濕地 ； 吸收或釋放 ； 人工濕地

並列摘要

Wetlands are highly productive ecosystems. The photosynthesis by aquatic and terrestrial plant in wetland will absorb CO_2 form atmospheric to form an organic carbon savings in the wetlands. Wetlands and forests play an important role on cycling of earth's carbon and they are also the important carbon storage space. The literature shows that constructed wetlands can be saved per year per square meter of carbon quality 1.5~2.2 kg. According this result, the constructed wetland in this study CO2 saved per square meter per year of 9.5 to 15.1 kg. This study carried out seven times wetland observation between 2008 and 2010, the main purpose of the experiment is to understand the constructed wetland at different season and under different processing units, CO_2 flux will be absorbed or released. The data shows the difference tendency among four seasons. In spring, there are sinking on fully vegetated surface area I and II. In summer, there are both sinks over the fully vegetated surface area and ecological pond; but in autumn, the open-water surface is the source. In winter, the preliminary treatment pond is a source, but fully vegetated surface area II and ecological pond are weak sinks. These results lead us to the conclusion that beside preliminary treatment pond, most of the areas are the sink over Daniaopi wetland. On daytime, it is weak sink on the area of preliminary treatment pond, but it becomes strong source on nighttime. One of the results of strong source is the respiration of active organic compounds. In the contrary, the photosynthesis leads to sink on fully vegetated surface area I and II. All of the areas, the vegetated surface area II is the minimum fluctuation during seasonal variation.

並列關鍵字

CO_2 flux ； Daniaopi wetland ； source or sink ； constructed wetland