頁籤選單縮合
題 名 | 利用相加性季節變動模式之德基水庫優養化時間數列分析=Application of Decomposition Method for Assessing Trophic Status in Te-Chi Reservoir |
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作 者 | 陳鴻烈; 梁家柱; 鄭慧玲; 王久泰; | 書刊名 | 水土保持學報 |
卷 期 | 31:3 1999.09[民88.09] |
頁 次 | 頁139-144 |
分類號 | 443.96 |
關鍵詞 | 相加性季節變動模式; 德基水庫; 優養化; 時間數列; Additive decomposition method; Te-chi reservoir; Trophic status index; Time series; |
語 文 | 中文(Chinese) |
中文摘要 | 本研究將以德基水庫中總磷資料計算優養指數TSI(Trophic Status Index),並利用相加性分解方法進行德基水庫水質優養化時間數列分析,用以瞭解水庫水質之優養化變化情形。一般時間數列的分析是分解現象的趨勢與時間變動。通常影響時間數列的成份包括:(T)長期趨勢,(S)季節變動,(C)循環變動,及(I)不規則變動。 統計學家在概念上作出不同的預測模式,其中比較通用的模式之一有相加性季節變動模式(additive decomposition method):Y=T+S+C+I。我們從結果分析得知:(1) 德基水庫 TSI 指標呈規律變化,其高峰期由四月到十月,為期七個月。(2)長期趨勢隨時間增加而變化,其關係為T=50.978+0.0728t。(3)循環變動週期會從二、三年後減少至一年或一年半。上述模式能夠有效地顯示優養化的變化,而德基水庫水質優養化的情形有日益嚴重的趨勢。 |
英文摘要 | The objective of this study is to apply the additive decomposition method as well as TSI (Trophic Status Index) to develop a practical procedure for time series analysis of an eutrophication conditions in reservoirs to exhibit trend and seasonal effects. The basic idea behind this model is to determine the trophic variation including trend (T), seasonal (S), cyclical (C), and irregular (I) changes. The results indicate that (1) TSI has regular change with a long high peak for seven months from April to October annually, (2) the long-term trend (T) increases with time (t) as following relationship: T=50.978+0.0728t, and (3) circular change period decreases from two or three years to about one year. The methodology is feasible to present the eutrophication change numerically. |
本系統中英文摘要資訊取自各篇刊載內容。