引言水是决定作物产量的关键因素。只有确保水的供应及有效利用,才谈得上充分发挥其它因素(高产品种、肥料、植保等)对作物生产潜力的影响。在灌溉稻作中,水分完全来自灌溉或来自雨水和灌溉的结合。在雨季,当雨水不足时,补充灌溉是重要的;而在旱季,当雨水很少或几 Introduction Water is a key determinant of crop yield. Only by ensuring the availability and efficient use of water can we fully exploit the impact of other factors (high-yielding varieties, fertilizers, plant protection, etc.) on crop production potential. In irrigated rice crop, the moisture comes entirely from irrigation or from a combination of rainwater and irrigation. In the rainy season, supplemental irrigation is important when there is insufficient rain; in the dry season, when there is little or no rain