湖南省季节性干旱对双季稻生长及产量影响的模拟研究

湖南省季节性干旱是水稻生产的主要灾害之一。在对水稻模型ORYZA2000校准验证基础上，模拟分析了1960—2007年不同水分管理方式(持续灌溉、间歇灌溉和雨养)下双季稻生育期间季节性干旱特点及其对水稻生长与产量的影响。结果表明，(1) 在间歇灌溉和雨养条件下，双季稻自幼穗分化前逐渐表现出稻田土壤季节性干旱特征，随着生育进程干旱不断加重，在雨养条件下，干旱特征随发育进程愈加明显；晚稻比早稻易受季节性干旱影响，生长后期较前期加重；双季稻开花期前后出现的干旱胁迫对生物量、产量影响最大；土壤干旱与作物干旱特征表现不同。(2) 早稻与晚稻在平水年型及干旱年型下均表现出干旱现象；在干旱年型下，早稻自穗分化至成熟期干旱都较为严重，且强度与持续时间要大于平水年型；晚稻干旱的频率和强度都大于早稻，尤其是从穗分化到成熟阶段。(3) 季节性干旱可造成不同程度的产量损失，间歇灌溉方式能够获得较高的产量，雨养水稻产量最低；雨养条件下晚稻产量普遍低于早稻产量。研究结果可为减轻季节性干旱的影响和合理水稻管理措施提供科学依据。

A Simulated Study on the Effects of Seasonal Drought on Growth and Yield of Double Cropping Rice in Hunan Province

Seasonal drought is one of the most serious disasters in rice production in Hunan Province of China.On the basis of calibration and validation of rice model ORYZA2000,the characteristics of seasonal drought and its effect on growth and yield of double cropping rice under three types of water management with continued flooding (CF),alternative wet and dry (AWD),and rainfed (RF) conditions were simulated and analyzed with history weather data from 1960 to 2007.The results were as follows,(1) The soil seasonal...