Seasonal dynamics, typhoons and the regulation of lake metabolism in a subtropical humic lake

Autor: Fang-Pang Lin, Jeng-Wei Tsai, Hsiu-Mei Chou, Bing-Shih Lin, Timothy K. Kratz, Peter Arzberger, Chih-Yu Chiu, Jiunn-Tzong Wu, Paul C. Hanson, William Y. B. Chang
Rok vydání: 2008
Předmět:
Zdroj: Freshwater Biology. 53:1929-1941
ISSN: 1365-2427
0046-5070
Popis: SUMMARY 1. We used high-frequency in situ dissolved oxygen measurements to investigate the seasonal variability and factors regulating metabolism in a subtropical alpine lake in Taiwan between May 2004 and October 2005, specifically exploring how the typhoon season (from June or July to October) affects lake metabolism. 2. Gross primary production (GPP) and ecosystem respiration (R) both peaked in early summer and mid-autumn but dropped during the typhoon season and winter. Yuan-Yang Lake is a net heterotrophic ecosystem (annual mean net ecosystem production )39.6 lmole O2 m )3 ). 3. Compared to the summer peaks, seasonal averages of GPP and R decreased by approximately 50% and 25%, respectively, during the typhoon season. Ecosystem respiration was more resistant to external disturbances than GPP and showed strong daily variation during typhoon seasons. 4. Changes in the quality and quantity of dissolved organic carbon controlled the temporal dynamics and metabolic regulation. External disturbances (typhoons) caused increased allochthony, increasing DOC and water colour and influencing lake metabolism. 5. Seasonal winter mixing and typhoon-induced water mixing in summer and autumn play a key role in determining the extent to which the lake is a seasonal carbon sink or source to the atmosphere.
Databáze: OpenAIRE
Externí odkaz: