The spatio-temporal distribution pattern of the rice leaf rollers was analyzed and the atmospheric circulation background in which the typical immigration process happened were studied.The model of FLEXPART-WRF was used to speculate the immigration path in order to illustrate the influence of atmospheric background on the path.The research results showed that (1) the bimodal type was the major type of the rice leaf rollers in 2008 and the most extensive serious immigration process was during the period from 15 to 18 July.(2) The representative station Huaiyin in Jiangsu Province was chosen to simulate the source by FLEXPART,and the immigration of the rice leaf rollers was from the middle of Jiangsu and the midwest of Anhui Province.(3) The synoptic situation including the distribution,movement and strength changes of weather system at 850 hPa isobaric surface played important transferring and controlling roles on the migration and landing of the rice leaf roller.The prevailing deflected-northward wind at 850 hPa isobaric surface was favorable for the northward migration of rice leaf roller.However,the prevailing deflected-southward wind at this height had no obvious influence on the southward migration.The zones with anticyclonic circulation in the wind field at 850 hPa isobaric surface were beneficial to the immigration and landing of the pest,and the cyclonic shear was beneficial to the emigrating of the pest.(4) The rainfall in the migrating paths of the rice leaf rollers played a critical role in the intensive landings of the pest.%在分析2008年我国稻纵卷叶螟时空发生规律特点的基础上,选取典型迁飞过程并对迁飞的大气背景进行分析,利用FLEXPART-WRF模式,对典型迁飞过程的路径进行逆推,以此明确大气背景对迁飞路径的影响.结果表明:(1)2008年稻纵卷叶螟发生峰型主要以双峰型为主,发生范围最广、程度最严重的北迁过程是7月15-18日过程.(2)通过FLEXPART计算逆推代表站,江苏淮阴的迁飞虫源来源于浙江中部至安徽中西部一线.(3)气压场上天气系统的分布、移动和强度变化对稻纵卷叶螟的迁飞和降落有重要作用;850 hPa风场上的盛行偏南风对稻纵卷叶螟的北迁有利;该高度上的反气旋环流对稻纵卷叶螟的迁入和降落十分有利;气旋性切变对稻纵卷叶螟的迁出有利.(4)稻纵卷叶螟迁飞路径上的降水对稻纵卷叶螟的降落有动力迫降作用.
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