毫米波扫描昆虫雷达空中昆虫监测的初步应用

Primary application of millimetric scanning radar to tracking high-flying insects in southern China

2007年6-10月，利用毫米波扫描昆虫雷达在广西兴安县植保站进行了空中昆虫的初步监测，结合地面灯和高空灯诱集，分析了地面和高空昆虫种群动态变化。结果表明：空中昆虫种群数量、种类季节性变化明显，6～9月夜间昆虫虫口密度相对较高，进入10月份夜间昆虫相对减少，雷达回波点密度和灯下诱集虫量有很高的一致性。夏季，19：00～22：00与05：30～07：00雷达回波密度各有一明显高峰期；秋季，只在20：00～21：00有一明显回波密度高峰期。昆虫飞行高度主要集中在2000m以下，大部分集中在500～1000m。姊妹灯诱捕表明，稻飞虱和稻纵卷叶螟为优势迁飞种类。昆虫飞行受气象条件影响较大。

Conventional 3-cm radars have been successfully used to observe the migratory flight of the larger insect species for many years, but the range within which these radars can detect individual small insects is limited to a few hundred meters. This paper outlines the primary application of an 8.0-mm wavelength scanning entomological radar to the study on the flight of insects in Guangxi in southern China. Using radars, searchlight traps, ground lighttraps and visual observations determined the nocturnal changes in aerial and ground density and composition of arthropods in flight over the sites under study. The results indicated that the insect density was relatively high from June to September, while the number of insects decreased. There is a high consistency between the density of target echoes and the quantities of insects trapped. In summer, there is a significant peak period of target echo density from 19：00 to 22：00 and from 05：30 to 07：00, respectively. In fall, however, there is a clear echo density peak only from 20：00 to 21：00. The flying altitude of insects mainly concentrated below the 2 000 m, with the majority concentrated in the 500-1 200 m. Light-trap catches indicated that the migrating insects in this season were mainly planthopper （Homoptera： Delphacidae） and rice leaf roller. At the same time, the weather conditions had a strong effect on insect density. This article mainly discussed about the capability of this system and described its primary application in the studies of insect migration in southern China.