108

2,950 千元

水環境建設-水與發展

2019/09/20

2020/05/31

林志麟

水保處

林治宇

社團法人水環境再生協會

水質保護

水質管理指標、卡爾森營養狀態指數、優養化

Water quality management index, Carlson trophic state index, Eutrophication

康世芳；游勝傑；王雅玢

陳余育

02-27772675#

linchen82028304@gmail.com

我國民生水庫集水區容易受降雨逕流或入庫溪水攜帶泥砂或懸浮固體物進入庫區而降低水庫水之透明度，造成卡爾森營養狀態指數(CTSI)值容易被高估，無法真實判斷水庫水質營養狀態。因此，本計畫重新檢視我國現行「卡爾森營養狀態指數(CTSI)」是否適用於我國的水庫水質管理，透過優養化潛勢高之水庫水質調查及藻華成因分析，建立本土性水庫水質營養狀態評估指標，以供水庫水質管理單位施政參考。 翡翠、石門、明德、鯉魚潭、仁義潭及澄清湖等六座代表性水庫水質調查結果顯示，總磷(TP)是國內多數重要民生水庫藻類生長之主要限制因子，且總磷成份以顆粒磷為主，降低總磷(TP)/總氮(TN)比可抑制藍綠藻滋生。另一方面，野外型藻類及葉綠素濃度分析儀(bbe-Moldaenke, FluoroProbeIII, Germany)應用於我國水庫水質現地評估，可藉由量測葉綠素a濃度及水溫掌握水庫不同深度水層之藻類生長狀態及熱分層現象，並可即時分析水庫優勢藻相對百分比，適合作為水庫水質優養化預警監測技術。此外，水庫水質大數據分析結果顯示，卡爾森營養狀態指數(CTSI)用於評估國內多數民生水庫水質營養狀態之適用性低，我國應自訂水庫水質管理指標。經歷年民生水庫水質大數據分析結果顯示，葉綠素a比CTSI更適合作為國內水庫水質營養狀態評估指標，指標修訂建議以原CTSI對應之TSI閾值推算各營養狀態葉綠素a濃度閾值(優養:Chl-a>7.2 µg/L;普養: 2.6≦Chl-a ≦7.2 µg/L;貧養: Chl-a<2.6 µg/L)。同時，保留現行CTSI，以利長期趨勢比較，指標呈現時分別註明新、舊指標之意涵，使民眾了解新指標之角色及功用。

水質管理指標、卡爾森營養狀態指數、優養化

指標計畫期末報告(定稿).pdf

13MB

公眾參與研訂我國水庫水質管理指標計畫定稿本

2020/9/1 上午 12:00:00

　　In Taiwan, a large amount of silts and sands or suspended solids in streams are frequently brought into reservoirs during intensive rain falls to reduce the transparency of reservoir water, which results in overestated Carlson trophic state index (CTSI) value. At such a condition, it is anticiptated that CTSI is failed to accurately evaluate trophic state of reservoir water. Therefore, this study aims to review the suitability of CTSI to reservoir water quality management. The characterization of water quality for reservoirs in high eutrophication potential and the evaluation of alge blooming were carried out simoltenously to formulate a local trophic state index for reservoir management divisions. 　　The results of water quality analysis for six candidates (i.e., Feitsui, Shimen, Mingde, Liyutan, Renyitan and Chengqing Lake reservoirs) showed that total phosphorus (TP) is the limiting factor of algae growth for most of reservoirs. TP is mostly composed of particulate phosphorus instead of dissolved phosphorus, and it is found that lowering the TP/TN (total phosphorus/total nitrogen) ratio has potential to supress blue-green algae growth. On the other hand, the on-site fluorescent probe can be used to chlorophyll a (Chl-a) and water temperature at different water level, which is helpful to determine algae growth state and thermo stratification in reservoirs and their relative percentage of algae species. It is anticipitated that on-site fluorescent probe is effectively used as a early warning technique in water quality management for eutrophicated reservoirs. In addition, the results of big data analysis on water quality of reservoirs showed that CTSI has low suitability to evaluate trophic state of most drinking water reservoirs. The results of big data investigation into water quality database showed that it is necessary to formulate local trophic state index for Taiwan reservoirs for which Chl-a is the most suitable index instead of CTSI. It is suggested that chlorophyll a threshold at different trophic state is determined by the inverse computation of its TSI threshold (i.e., eutrophic: Chl-a>7.2 µg/L, mesotrophic: 2.6≦Chl-a ≦7.2 µg/L, oligotrophic: Chl-a<2.6 µg/L ). Meanwhile, the current CTSI is still used for the long term comparision in results between new and old trophic state index. The meanings of new and old trophic state index should be noted when they are announced to let populace understand their role and effectiveness.

Water quality management index, Carlson trophic state index, Eutrophication