農作物淹水警戒基準值之建立-以雲林西螺二崙短期葉菜為例

Abstract

短期菜類作物在夏季時為國內主要新鮮蔬菜來源，但也因為其組織柔軟，易受颱風豪雨損害。近年來全球受極端天氣影響，極端降雨不斷發生，以至於淹水災害的衝擊愈來愈大，而使颱風過後短期葉菜無法及時供應，故本研究將評估臺灣重要農業生產區─雲林地區短期葉菜之淹水災害警戒值。 本研究利用羅吉斯回歸分析(Logistic regression analysis)進行評估，將二維淹水模式重現重大淹水事件之淹水深度及淹水時間與天然災害救助資料建立短期葉菜淹水受害模式。並根據情境模擬分析，比較受害面積比率與情境雨量之關係，繪製短期葉菜受害機率地圖，推估適用於雲林二崙西螺短期葉菜之農作物淹水災害警戒值，用以做為減少損失風險規劃之依據。

In Taiwan, Leafy vegetables from short-lived herbaceous plants have high production in summer. However, the fragile leaves of these vegetables will suffer from Typhoon and heavy rainfall. Owing to the increase in extreme weather events in recent years, frequent flood disasters caused by heavy rainfall result in significant decrease in the production of leafy vegetables. Under such circumstance, we aim at developing an approach to study the impact of flooding on the production of leafy vegetables and also apply the proposed model to the agricultural areas in Yunlin, Taiwan. In addition to provided records of natural disaster financial assistance, inundation depth and time in several real flood events are computed based on a two-dimensional inundation model. The formulation among the inundation depth and time, records of natural disaster aid and decrease in production of leafy vegetables is therefore established by virtue of the logistic regression. Furthermore, risk maps of decrease in production of leafy vegetables at any rainfalls can be presented through the established formulation. Depending on the risk maps, a warning rainfall criteria is proposed to conduct a risk assessment of decrease in production of leafy vegetables in Yunlin in this study.