都市農業によるレジリエンスの形成 : 東京を事例とした災害時における食料安全供給のための蔬菜・栄養の自給率算定

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 横張 真, 東京大学准教授 梅崎 昌裕, 東京大学特任准教授 松田 浩敬, 東京大学特任准教授 関山 牧子, 東京大学講師 寺田 徹University of Tokyo(東京大学

Resilience with Mixed Agricultural and Urban Land Uses in Tokyo, Japan

Urban agriculture can enhance the resilience of neighborhoods by providing fresh food in times of natural disasters; however, there is little empirical evidence to support this. Therefore, this study proposes a methodology to identify patterns of agricultural production in urban areas by quantifying self-sufficiency rates in vegetable weight and key nutrients. A spatial grid cell analysis using a geographic information system (GIS) identifies the current and potential self-sufficiency of each land use pattern in Tokyo. In a total of 1479 grid cells, the dominant land use and locations of 49,263 agricultural plots led to the categorization of six distinguishable land use patterns. The results showed that Tokyo has a fruit and vegetable self-sufficiency of 4.27% and a potential of 11.73%. The nutritional self-sufficiency of selected nutrients was the highest in vitamin K (6.54%), followed by vitamin C (3.84%) and vitamin A (1.92%). Peri-urban areas showed the highest resilience in relation to aggregated risks and population density because of the mixture in agricultural and urban land uses

Post-Disaster Food and Nutrition from Urban Agriculture: A Self-Sufficiency Analysis of Nerima Ward, Tokyo

Background: Post-earthquake studies from around the world have reported that survivors relying on emergency food for prolonged periods of time experienced several dietary related health problems. The present study aimed to quantify the potential nutrient production of urban agricultural vegetables and the resulting nutritional self-sufficiency throughout the year for mitigating post-disaster situations. Methods: We estimated the vegetable production of urban agriculture throughout the year. Two methods were developed to capture the production from professional and hobby farms: Method I utilized secondary governmental data on agricultural production from professional farms, and Method II was based on a supplementary spatial analysis to estimate the production from hobby farms. Next, the weight of produced vegetables [t] was converted into nutrients [kg]. Furthermore, the self-sufficiency by nutrient and time of year was estimated by incorporating the reference consumption of vegetables [kg], recommended dietary allowance of nutrients per capita [mg], and population statistics. The research was conducted in Nerima, the second most populous ward of Tokyo’s 23 special wards. Self-sufficiency rates were calculated with the registered residents. Results: The estimated total vegetable production of 5660 tons was equivalent to a weight-based self-sufficiency rate of 6.18%. The average nutritional self-sufficiencies of Methods I and II were 2.48% and 0.38%, respectively, resulting in an aggregated average of 2.86%. Fluctuations throughout the year were observed according to the harvest seasons of the available crops. Vitamin K (6.15%) had the highest self-sufficiency of selected nutrients, while calcium had the lowest (0.96%). Conclusions: This study suggests that depending on the time of year, urban agriculture has the potential to contribute nutrients to diets during post-disaster situations as disaster preparedness food. Emergency responses should be targeted according to the time of year the disaster takes place to meet nutrient requirements in periods of low self-sufficiency and prevent gastrointestinal symptoms and cardiovascular diseases among survivors