四川盆地水稻不同生育期干旱频率的空间分布特征

将四川盆地按地理地貌类型及水稻种植区划分为5个区域即盆南、盆中、盆西、盆周和盆东,基于区内102个县(市)气象台站1980-2014年的逐日气象资料及32个农业气象观测站的水稻生育期资料,利用干旱评估指标分析四川盆地水稻各生育期干旱发生频率的空间分布特征。结果表明:水稻移栽-分蘖期干旱频率在盆中及盆南部分区域高达90%以上;分蘖-拔节期及拔节-孕穗期干旱频率也相对较高,大部地区集中在50%~90%;水稻孕穗-抽穗期和抽穗-成熟期的干旱发生频率与其它生育期相比较低,孕穗-抽穗期干旱发生频率除盆西部分区域、盆中及盆东北局部在70%~84%以外,其余大部在50%左右;抽穗-成熟期干旱发生频率大部分在50%~70%。

Spatial Distribution of Rice Drought Frequency during Different Growth Periods in Sichuan Basin

Drought significantly influences rice growth and development and has caused great loss of rice production in the Sichuan basin. The basin was divided into five rice growing regions based on its landforms and cropping systems in this paper. Authors analyzed the spatial distribution characteristics of drought frequency for each growth period of rice in the basin in terms of drought assessment index, using historic daily weather data from 102 meteorological monitoring stations between 1980 and 2014 and the phonological data from 32 agro-meteorological observation stations. The results showed that drought frequency was over 90% during the transplanting and tillering stages in parts of the middle and southern basin. During the periods from tillering to jointing stage and from jointing to booting stage, the drought frequency varied between 50% and 90% over the majority area of the basin. The frequency occurred during the periods from booting to heading stage and from heading to mature stage was lower compared with that during the other stages. It was about 50% during the period from booting and heading stage over most of the basin, apart from parts of the western, central basin and northeastern basin where the frequency was around 70%-84%. And the frequency was about 50%-70% during the period from heading to mature over most of the basin.