Gross Irrigation Demand April Schedule: Demand Irrigation At 0.5 Paw

This data set contains the GROSS IRRIGATION DEMAND Schedule: Demand Irrigation at 0.5 PAW in South Africa. Gross irrigation demand is the gross irrigation water that needs to be abstracted from a source of water (e.g. dam) to satisfy the irrigated crop`s water requirement. In demand irrigation, conveyance losses of 10% were assumed, while wind/spray drift losses were set at 12% (assuming overhead irrigation), with crop interception losses at 1.5 mm per irrigation application. The soil profile was depleted to 50% of plant available water (PAW), i.e. by 45 mm (50% of 234 - 144 mm) before irrigation was applied to refill the soil profile to its drained upper limit (DUL).

本数据集涵盖南非地区植物有效含水量（Plant Available Water，PAW）降至0.5时的总灌溉需水量（Gross Irrigation Demand）时间表。总灌溉需水量指需从水源（如水库）抽取的总灌溉水量，用于满足灌溉作物的需水要求。本次需求灌溉场景中，设定输水损失率为10%，风/喷溅漂移损失率为12%（假设采用地上喷灌方式），单次灌溉的作物截留损失为1.5毫米。灌溉实施前，土壤剖面的植物有效含水量被消耗至50%，即耗水量为45毫米（234毫米与144毫米差值的50%），随后通过灌溉将土壤剖面补水至其田间持水量（Drained Upper Limit，DUL）。