台风莫兰蒂对褐飞虱迁飞的影响

通过对2010年10号台风莫兰蒂(Meranti)进行流场分析和过程分析,阐明了此次台风对浙江稻区9月上中旬褐飞虱Nilaparvata Lugens(Stl)的迁飞造成的影响。结果表明:(1)台风过境前,其外围前方的强东南气流及高空下沉气流为褐飞虱提供了运载工具和降落条件,虫源基本来自浙江东南部和迁入区附近区域;(2)台风过境时,由于天气恶劣,部分站点上灯虫量很小,但金华和遂昌处于台风眼范围内,天气较好,风速较小,为之前随大风和降雨迁入的大量虫群提供上灯的机会,造成上灯高峰,虫源地主要来自浙江省南部;(3)台风过境后,受台风后部西南风和降雨影响,福建中北部和南部有褐飞虱随降雨迁入浙江稻区,但虫量较小。(4)根据浙江为东部临海的地理位置和台风的气旋式辐合流场的特点,从本研究结果看,莫兰蒂台风的影响仅为中小尺度范围。

The influence of typhoon Meranti(1010) on migration of Nilaparvata lugens

The influence of typhoon Meranti on the migration of the brown planthopper（BPH） Nilaparvata Lugens（Stl） was analyzed in September 2010.The following results were obtained：（1） Before the advent of the typhoon,the upper air was affected by a strong southeast wind and downdraft which favored the migration and settlement of BPH from the periphery of the typhoon.The source region of the immigrants was southeastern Zhejiang and nearby areas.（2） There were few light trap catches of BPH on the day of the typhoon at most stations except for Jinhua and Suichang.This might be because these stations were in the eye of the typhoon and consequently experienced fine weather with light breezes and a downward airflow.The source region of the immigrants to these sites might be the nearby southern part of Zhejiang Province.（3） After the passage of the typhoon,areas at the rear of the typhoon experienced prevailing southwest wind and rainfall which may have resulted in a small light trap capture peaks of immigrants from the north-central and southern parts of Fujian Province.（4） These results suggest that the geographical position of Zhejiang on the east coast,combined with the cyclonic convergence field,create conditions for the medium and small scale migration of rice planthoppers from this region.