大臺北地區食物物質流與生產空間分析

Abstract

受到都市擴張影響，造成都市內部農地變遷，因人口增長與社會經濟變化，大量初級產業用地紛紛轉變為住宅、文教、工商業等土地利用類型，但農業用地的減少，直接影響了都市糧食安全與環境負荷，因此糧食生產調適與自給安全等議題受到世界各國重視，而臺灣亦是如此。故本研究欲探討大臺北地區從日治時期1905年至2012年，稻米種植面積變化所造成之大臺北地區稻米供給數量改變情形，分別使用臺灣堡圖(歷史圖資)、美軍航照、Landsat-1衛星影像以及福衛二號衛星影像(航遙測影像)建置稻田空間分佈，獲得四時期稻田面積為44,417、33,438、19,399、520公頃，並搭配農委會農業統計年報調查資料探討研究區內稻米、蔬菜、豬肉此三項食物之生產情形，進一步分析三項食物之生產、消費空間情形，並結合大臺北地區不同時期食物物質流分析。城鄉發展不僅是都市規劃的主要問題，也是都市永續發展的一個核心議題，本研究透過糧食供給與消費的概念，量化不同都市間的互動關係，並且還原都市內部糧食需求與供應之差異。由於都市擴張導致糧食減產，嚴重降低了糧食供應能力，因而衍生都市糧食安全問題，並對外縣市造成相關環境負荷，如本研究結果顯示，每年大臺北地區之食物消費將為其他縣市帶來約15億公斤的碳排放量，而水足跡總量達24億立方公尺。

Urban sprawl can result the loss of food production in the urban area and then affect the food security of urban population. The purposes of this study are (1) to analyze the impact of urban sprawl on farmland conversion by using spatial data and (2) to find the food material flow system of Taipei Metropolitan. The 1905, 1947, 1972, and2012 years of rice field spatial data combined with material flow analysis (MFA) data in Taipei Metropolitan were used to find rice fields spatial change among these four periods. Finally, through the result of Taiwan rice field spatial distribution and the number of rice distribution between cities, the food providing areas (FPAs) and food consumption areas (FBAs) of Taipei metropolitan can be identified. The urban sprawl not only causes the food security problem of a city but also results in environmental loadings to other rural areas. Hence, food production and consumption system has become a central theme of sustainable city planning and management. This study shows that urban sprawl causes the loss of food production, the decrease of food security and the decline of sustainability of farming activities that result in disharmonious urban and rural relationships and threaten the sustainability of the city and other rural areas. The results of this study show the total food consumption of Taipei Metropolitan per year will result in 1.5 billion kilograms of carbon emissions and 2.4 billion cubic meters of water footprint from other food production counties in Taiwan.