《环境昆虫学报》

【目的】为探究大气准双周振荡对华南白背飞虱Sogatella furcifera迁入过程的影响，揭示在迁入不同阶段（峰期-谷期）低频大气环流场的特征及其影响机理。【方法】本研究基于2011-2016年华南20个站白背飞虱灯诱数据，对3-5月迁入虫量作Morlet小波分析，提取其低频振荡周期；通过相关分析挑选出与迁入量显著相关的低频大气环流要素场；最后利用位相合成法，分析大气低频振荡对白背飞虱迁入过程各个阶段的影响，总结特殊位相时低频大气环流场的多年平均气候态特征。【结果】结果显示，华南稻区白背飞虱迁入虫量存在10~20 d的主要低频振荡周期，与大气准双周低频振荡的周期相吻合；影响白背飞虱迁入虫量低频变化的关键大气环流背景包括低频风场和低频位势高度场；当西太平洋与日本海上的气旋环流发展增强以及南海及孟加拉湾上的反气旋式环流减弱时，虫源地至华南稻区的盛行风向由西南风转变为东北风，这种环流形势的转变对白背飞虱的迁入形成阻滞；然而，低频高度场正异常形势和副热带高压的北抬增强对其迁入十分有利。【结论】因此，大气准双周振荡通过风场及位势高度场的配置与演变，从动力层面影响华南前期迁入虫量。可利用大气环流准双周信号（如纬向风是否处于活跃位相）为白背飞虱迁入的中期预测预报提供有效的预测指标。

英文摘要:

【Aim】This study aims to investigate the influence of quasi-biweekly oscillations on the immigration of the white-backed planthopper (Sogatella furcifera) into southern China, with a focus on the characteristic low-frequency atmospheric circulation fields and their mechanisms during different immigration phases (population peak and trough periods).【Methods】Light-trap data from 20 stations across South China (2011-2016) were analyzed. The Morlet wavelet analysis was employed to extract the dominant low-frequency oscillation period of the immigration population during March-May. Key low-frequency atmospheric circulation elements significantly associated with immigration volume were then identified through correlation analysis, and their phase-dependent influences were examined using phase composite analysis, and the climatological characteristics of low-frequency circulation fields during specific phases were summarized.【Results】The analysis revealed a dominant low-frequency oscillation period of 10~20 days in the immigration volume of white-backed planthopper in South China, consistent with the period of atmospheric quasi-biweekly oscillations. The low-frequency wind and geopotential height fields were identified as the primary circulation backgrounds influencing immigration. A regime shift from southwesterly to northeasterly winds-driven by the strengthening of cyclonic circulation over the western Pacific/Sea of Japan and the weakening of anticyclonic circulation over the South China Sea/Bay of Bengal-was found to suppress immigration from source areas to South China. In contrast, positive low-frequency height anomalies and a northward shift of the subtropical high facilitated immigration.【Conclusion】Therefore, atmospheric quasi-biweekly oscillations dynamically modulate immigration through the configuration and evolution of wind and geopotential height fields, indicating that quasi-biweekly signals, such as the activity phase of zonal wind, can support medium-term forecasting of white-backed planthopper immigration.

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