本計畫規劃研究陸氣水與能量循環中土地利用類型與乾旱之關係，擬利用長期觀測資料，探討土地利用如何改變能量分配，進而影響局部和全球氣候。規劃三年期計畫，基於本實驗室架設的自動化觀測站，補強現有設備，搭配中國「黑河流域生態－水文過程綜合遙感觀測聯合試驗」（HiWATER）提供遙測影像與固定觀測站成果，探討相異土地利用和氣候因素如何影響能量通量分配，並量化乾旱強度和範圍在不同土地利用之影響程度，以了解土地利用之改變，如何反饋並影響局部和全球氣候。本研究第一年期(2018/8-2019/7):將利用本實驗室長時間的觀測資料，比較不同氣候條件下，自然因素(氣候情況)和人為因素(土地利用)對能量分配的影響，並開發適用於研究地區之新的土地利用乾旱指標，來探討土地利用對包溫比(Bowen Ratio)的影響。第二年(2019/8-2020/7)將評估土地利用改變之後，對乾旱影響之效應。透過不同時期乾旱指標的對比，將能夠反應人為乾旱和自然乾旱所造成之加成效應。第三年(2020/8-2021/7)將配合黑河流域與嘉義地區遙測與地面站長期資料，分析探討不同時間和空間尺度下，土地利用改變對乾旱的影響，並考慮自然和人為因素，發展新的包溫比模式。透過全面性的分析，將對旱情減災、熱島效應調適及國土和水資源規劃具有潛在的效益。 ;In this project, we aim to study the relationship between land use/cover (LULC) and drought under the framework of land-atmosphere water and energy cycle. Long-term energy flux data will be utilized to answer a critical question how LULC affects energy partitioning and what impacts they are in regional and global climates. We propose a three-year project to investigate how heterogeneous LULC and climate factors alter energy partitioning, quantify duration and intensities of drought, and understand how LULC changes affect regional and global climates based on long-term data from our ASOS (Automated Surface Observing System) sites and HiWATER (Heihe Watershed Allied Telemetry Experimental Research) project. Hence, the first-year (2018/8-2019/7) plan is to analyze the data from our ASOS sites to understand the partitioning of surface energy in response to different climates and LULC changes and the associated signatures of Bowen ration, base of a newly-developing drought index. That is, a landuse-adapted drought index will be developed to study what impacts LULC would have on Bowen ratio. In the second year (2019/8-2020/7), we will evaluate LULC changes’ impacts on drought events through comparing new drought index before and after land use changes. Then, we can assess combined impacts from natural drought and anthropogenic drought. In the third year (2020/8-2021/7), under different spatial and temporal scales, we will evaluate these terrain change’s effects on drought occurrence, and develop a new Bowen ratio model based on climate and land cover factors. By these comprehensive analyses, it is expected to have significant benefits for drought disaster reduction, heat island effects, and national land and water resource plans.
