濁水溪下游河段揚塵發生之影響因素

Factors Affecting Aeolian Dust Emission in the Down-stream of Zhuo-shui River

10.29417/JCSWC.201212_43(4).0005

林昭遠(Chao-Yuan Lin)；林政侑(Cheng-Yu Lin)

濁水溪 ； 河川揚塵 ； 預警系統 ； Zhuo-shui River ； aeolian dust emissions ； warning system

中華水土保持學報

43卷4期（2012 / 12 / 01）

323 - 331

繁體中文

濁水溪旱季時河道水位降低，河床裸地面積增加，適逢東北季風吹襲，因缺少植生及水覆蓋，細小砂粒易受風力揚起形成揚塵，對鄰近居民健康造成極大危害。如何篩選影響河川揚塵發生之因素，建置河川揚塵濃度推估模式，對揚塵危害區位預警系統雛型之研發極為重要。本研究以濁水溪下游河段為樣區，蒐集鄰近樣區之氣象資訊及衛星影像資料，分析氣象及土地利用等因素對河川揚塵發生之關係，建立河川揚塵濃度推估模式。結果顯示河川揚塵事件日之各氣象因素與PM10濃度在時序上，其峰值有遲滯現象，模式建置時須加以調整。整合氣象因素及土地利用所建置之日最大PM10濃度推估式，其判定係數可提升至0.77，已能有效反應崙背測站揚塵日最大PM10之濃度變化，所建置之模式可供河川揚塵預警系統研發之參考。

Bare lands in the Zhuo-shui River are increasing due to decreasing water levels in drought seasons. The smaller particles of the bare lands lacking vegetation cover and/or water could be easily suspended and became aeolian dust under the northeast monsoon. It would seriously affect the nearby residents' health. Screening for the affecting factors and establishing the evaluation model are important to develop the warning system for areas vulnerable to aeolian dust emission. The downstream section of the Zhuo-shui River was selected as the study area. Meteorological data and satellite images were collected to analyze the main factors causing the aeolian dust emission for establishing the PM10 estimation models. The results indicate the established models should be adjusted due to the time-lagging phenomenon of peak occurrence between meteorological factors and PM10 in time series plotting. The coefficient of determination reached 0.77 by combining meteorological factors and land use to evaluate the daily maximum PM10, and the model shows the variations in concentration of the daily maximum PM10 at Lunbei monitoring station. The model developed in this study could be used as a reference for the warning system of aeolian dust emissions.