Cool Island Effect of Farm Pond in Taoyuan City

With the rapid development of society, and the booming urban systems nowadays, original natural surface is being replaced by artificial surfacing gradually. The temperature is losing balance in urban areas, and temperature constantly rising end up with higher temperature in the city outskirts; which leads to Heat Island Effect in cities. Therefore, how to alleviate the problem of Heat Island Effect caused by urbanization is getting more important. More and more researches on the effect of Cool Island Effect appeared, but most of the studies for Cool Island Effect focus on green spaces, and those on the water are mostly ribbon of river; However, the study focused on planar of waters is relatively rare, so my study will focus on the waters of the planar for the object. With the swift development of Taiwan's economy, the Heat Island Effect not only happened in Taipei area, but also in the nearby city, Taoyuan. Therefore, Heat Island Effect problem should not be ignored. With the natural conditions and the background of demanding ancestors Taoyuan areas, ponds become the most representative of the landscape in Taoyuan City. Therefore, this study will focus on the planar of pond in Taoyuan City as the study objects of cool island effect. With the progress in information and technology of space, Satellite Telemetry has the advantages of high spectral, large range, simultaneous record and the rapid acquisition data. Therefore, this study will refer to the remote sensing images of 2002 and 2011 of the Landsat-7 ETM +, with the calculation of the surface temperature and ground station data, and then produce the surface temperature map of Taoyuan City; On the other hand, take the advantage of the land use classification, this research divided land of Taoyuan city in five categories which is ponds, water, woodland, agricultural land and building. The spatial overlay analysis is to explore the relationship of Cool Island Effect between ponds in Taoyuan against the surrounding environment, and the data in ponds Cool Island Effect as well. The results showed that Cool Island Effect would affect 300 meters from ponds, and the environment location and the area of ponds will affect its Cool Island Effect. Pond area to the temperature showes negative correlation. However, the area of influence of the Cool Island Effect has a threshold, once it exceeds the threshold, the impact will slow down. the best area is about 2-5 hectares, it varies in different locations. The Cold Island Effect for ponds to cool down in the range of 1 to 2.5℃. But with the different density of buildings would make different cool data. Therefore, this study will collect Cool Island Effect data from ponds to Cool Island Effect table, providing researches, space planning or design in the future.隨著社會經濟的進步，以及現今都市的蓬勃發展，原始之自然表面也逐漸被人工鋪面所取代，都市地區溫度失去平衡，溫度不斷地升高，導致都市溫度高於郊區，形成都市熱島效應，因此如何緩解都市化所帶來的熱島效應問題則越發重要，越來越多關於冷島效應之研究也逐漸出現，但是研究多針對綠地空間之冷島效應，且水體之冷島效應研究也多為帶狀之河川水域，面狀水域之研究則相對稀少，故本研究將針對面狀水體為對象。 台灣經濟快速的發展，不僅大台北地區熱島效應影響明顯，其鄰近之桃園市也面臨都市化問題，故其熱島效應問題也不可忽視，而桃園地區由於自然條件及先民需求等背景下，埤塘成為桃園市最具代表之景觀，因此本研究將針對桃園市埤塘之面狀水體為冷島效應之研究對象。 隨著空間資訊與技術的進步，衛星遙測具有高光譜、大範圍、同時間以及資料獲取快速等優點，故本研究將使用2002年以及2011年之Landsat-7 ETM+遙測影像，藉由地表溫度之計算以及地面監測站資料，製作桃園市之地表溫度圖；另一方面透過土地使用分類，將桃園市之土地使用分為埤塘、水體、林地、農地以及建地等五類，並利用地理資訊系統(GIS)之空間疊圖分析，探討桃園埤塘與周邊環境間冷島效應關係，以及埤塘冷島效應數據。 研究結果顯示埤塘之冷島效應距離最遠達300公尺，且埤塘所在區域環境以及埤塘面積將影響其冷島效應，埤塘面積對於埤塘本身溫度具負相關性，但是其面積對冷島效應之影響有閾值，一旦超過閾值則影響趨緩，面積約為2-5公頃，依其所在區域不同而異，而埤塘本身冷島效應降溫範圍為1至2.5oC，但是隨著周邊所在區域建築密度不同而有差異，故本研究將整理埤塘冷島效應數據為冷島效應降溫對照表，供後續研究及空間規劃設計使用。第一章 前言 1 第一節 研究動機與目的 1 第二節 研究流程 3 第二章 文獻回顧 4 第一節 都市發展及影響 4 一、都市發展 4 二、桃園埤塘 6 三、熱島效應 8 四、冷島效應 9 第二節 遙測與地表溫度之計算 11 一、溫度資料獲取方法 11 二、遙測技術應用於地溫計算 13 第三節 遙測與土地使用分類 21 一、均值最小距離法 21 二、平行六面體法 22 三、高斯最大相似法 22 第三章 研究方法 24 第一節 研究範圍 24 第二節 遙測影像處理 25 一、地表溫度 25 二、土地使用分類 32 第四章 研究成果 37 第一節 埤塘冷島效應之影響距離與因子 37 一、埤塘與周邊溫差 37 二、影響埤塘冷島效應因子 37 第二節 不同區域之埤塘冷島效應 46 一、埤塘所在區域 46 二、不同區域之埤塘面積與冷島效應關係 48 三、不同區域之埤塘冷島效應 73 第三節 結果討論 80 第五章 結論與建議 82 第一節 結論 82 第二節 建議 8