四川地区白背飞虱虫源地分析及迁入路径

为明确四川稻区白背飞虱迁入种群虫源地分布及迁飞路径,运用HYSPLIT 4.8平台和Arc GIS对2012年四川17个站点5—7月白背飞虱灯诱高峰日进行了轨迹模拟、虫源地分析,并运用气象图形处理软件Grads对白背飞虱主要迁入高峰日的虫源地进行风场分析。结果表明:(1)早期5—6月迁入四川盆地的白背飞虱主要降落于川南和川东地区,川南早期虫源主要来自越南和老挝北部和云南南部、东部及东北部地区,川东主要集中在重庆南部、湖南西部以及湘鄂渝交界处,少量来自广西西北部地区,7月白背飞虱的迁飞因受到西南、偏南及东南气流的影响,其虫源广泛分布于云南、贵州、重庆、广西、湖南及湖北。(2)白背飞虱迁入四川盆地的路径主要有4支,第一支,白背飞虱随西南或偏南气流由云南经贵州西部迁入川南,或再经贵州东北部和重庆迁入川东;第二支,白背飞虱随偏南气流由广西经贵州中部迁入川南,或经贵州东北和重庆迁入川东;第三支,由湖南经重庆随东南或偏南气流迁入川东;第四支,由云南随偏南气流迁入川西。(3)由于特殊地形地势的影响,四川盆地白背飞虱的迁入始期和主要迁入期是由东南向西北发生发展;四川稻区白背飞虱主要迁入峰集中在7月份,早期5—6月高峰数较少,且集中在川南和川东地区,总体上迁入峰变化表现为由东南至西北依次减少,以上对四川稻区白背飞虱监测预警有重要意义。

Origins and migration pathways of white-backed planthopper Sogatella furcifera (Horváth) in Sichuan

We analyzed the distribution of the origins and migration pathways of white-backed planthoppers (WBPHs), Sogatella furcifera (Hemiptera; Insecta), in Sichuan, China. The WBPHs were collected daily from light traps at seventeen stations between May and July, 2012. The trajectories and distributions of the source areas during the peak days of WBPH migration were simulated and analyzed using HYSPLITY4.8 (Hybrid Single-Particle Lagrangian Integrated Trajectory) and ArcGIS. Additionally, the meteorological backgrounds of the WBPH immigration peak source areas were analyzed using Grads (Grid Analysis and Display System). During the early migratory stage (May-June), S. furcifera congregated in the southern and eastern areas of Sichuan. WBPHs from south Sichuan traveled to northern Vietnam and Laos, and to the southeast and northeast of Yunnan Meanwhile,WBPHs sourced from the eastern parts of Sichuan were found south of Chongqing, west of Hu'' nan, and at the border junction of Hu'' nan, Hubei, and Chongqing (which partly extends into southwestern Guangxi). In July, influenced by the southwesterly, southerly, and southeasterly winds, the WBPH sources were widely distributed in Yunnan, Guizhou, Chongqing, Guangxi, Hu'' nan, and Hubei. The main sources in early July were Yunnan, part of mid-western Guangxi, and west of Guizhou. In mid-July, the sources shifted to the northeast, namely, northeastern Yunnan to central Guizhou. Meanwhile, WBPHs originating from south Sichuan may have migrated to central and eastern Sichuan. In late July, WHPHs may have traveled from western to northern Sichuan. At other stations, the source distributions were more average. We also found four main migratory paths of WBPHs in Sichuan. The first path extends from west Guizhou to south Sichuan. Under southwest and southerly airflows, the path continues through northeast Guizhou, Chongqing, to east Sichuan. The second path extends from central Guizhou to south Sichuan, or (aided by a southerly wind) through northeast Guizhou, Chongqing to east Sichuan. The third path extends from Hunan, through Chongqing, and to east Sichuan. This path is helped by southeast and southerly air flows. The fourth path extends from Yunnan to west Sichuan under a southerly airflow. Because of the spatial topography, the WBPHs tended to migrate from southeast to northwest during the beginning and mid-period of the migration. The migration peaks varied at different stations and in different periods. The migration of WBPHs in Sichuan generally peaked in July, whereas the WBPH migrations in southern and eastern Sichuan peaked to a lesser extent in May and June. Overall, the major migration peaks were reduced from southeast to northwest. The accurate monitoring and prediction of WBPH in Sichuan is important.