Consumptive Use of Water and Optimal Irrigation Scheduling in Greenhouse Culture

日本的温室栽培是为了在夏季雨量过多、冬季气温过低的情况下控制适宜的生长条件而发展起来的。温室栽培有很多优点。它可以种植许多种在露天地里难以种植的作物，也可以种植消费者需要的高质量作物。人工气候和土壤湿度控制使温室耗水条件复杂化。温室中使用的滴灌、雾灌和微喷等微灌系统使蒸散现象复杂化。为了解决这些困难，本研究提出了一种确定需水量的分析方法。首先，讨论了温室壁面的辐射平衡；其次，提出了作物结构模型，用于估算作物冠层各生长阶段的辐射环境。第三，建立了包括三维土壤水分流动和作物蒸腾作用在内的土壤-植物系统水流模型。这些模型可用于控制灌溉调度。

The greenhouse culture in Japan has developed for controlling suitable growing conditions in spite of excess rainfall in summer season and too much low temperature in winter season. The greenhouse culture has many advantages. It enable to grow many kind of crops, which are difficult to grow in the open field and it enable to grow high qualified crops which are required by consumers.Water consumption conditions in a greenhouse complicated by the artificial climate and soil moisture control. Micro irrigation system such as drip, mist and micro sprinkler used in greenhouses complicated the evapotranspiration phenomena. To cope with these difficulties, the present study proposes an analytical method for determining water demand. First, radiation balance at the greenhouse wall is discussed, Second, a crop architecture model is proposed to estimate the radiative environment at all growing stages of crop canopy. Third, a water flow model in soil-plant systems which includes three dimensional soil moisture flow and crop transpiration is proposed. These models are applied for controlling irrigation scheduling.