濁水溪揚塵潛在發生區位劃定之研究

Potential Areas of the Aeolian Dust Occurrence in the Zhuoshui River

林昭遠(Chao-Yuan Lin) ； 莊智瑋(Chin-Wei Chuang)

《中華水土保持學報》 40卷3期 (2009/09) Pp. 87-96

https://doi.org/10.29417/JCSWC.200909_40(3).0006

摘要

濁水溪旱季來臨時，下游河道因上游截水致河床裸露面積大增，在缺少粗粒徑的礫石敷蓋，細小顆粒易被東北季風吹襲，造成大氣中的懸浮微粒濃度過高，嚴重影響鄰近居民的生活品質。濁水溪河道流路每年暴雨後變動極大，加上旱季退水期間瓜農墾植區位之變化亦大，導致河川裸地揚塵潛在發生區位須年年更新製作。另由於光譜解析度不足，傳統影像處理技術不易由衛星影像中區別河床裸地與整地初期之農地。在經濟考量上，如何藉由衛星影像早期快速劃定河川裸地揚塵潛在發生區位，供河川管理機關儘早擬定揚塵抑制對策極爲重要。本研究以揚塵災害最爲嚴重之河段（自強大橋至西濱大橋），利用SPOT衛星影像進行揚塵潛在發生區位之劃定；顯示結合影像分類及邊緣萃取技術可經濟有效劃定濁水區揚塵潛在發生區位。

關鍵字

濁水溪 ； 揚塵 ； 邊緣萃取

並列摘要

In Zhuoshui River, areas of bare soils increase and lack of gravel's mulching protection on the surface of downstream riverbed due to interception of debris and/or water at the upstream segments, the smaller particle matter can then be easily eroded by the monsoon, and cause serious air pollution that significantly affects the living quality of the nearby residents at the dry season. Variations of flow paths in the river channels are frequently governed by the annual storms, and the spatial distribution of highland suitable for melons cultivated are also changed annually. Hence, locating the potential areas of the aeolian dust occurrence annually is quite necessary. Traditional technique of image process can not be employed to tell apart the bare soils and the initial phase of cultivated fields through satellite image due to limitation of spectrum resolution. How to delineate the potential areas of the aeolian dust occurrence economically for the reference of related government to frame the countermeasures of dust control is a vital issue. This study focused on the dust vulnerable segment (Bridge Ziqiang to Xibin) of the Zhuoshui River by using SPOT image and integrating the techniques of image process couples with edge extraction to delineate the potential areas of aeolian dust occurrence in the River.

並列關鍵字

Zhuoshui River ； Aeolian dust ； Edge extraction