Insect Species Diversity And Main Pests Occurrence Of Platycladus Orientalis In Huangdi Mausoleum

Hangdi Mausoleum is the tomb location of Chinese nation's cultural ancestor,Platycladus orientalis is the main tree species in this land,which has formed the largest and most complete preservation ancient forest after thousands of years.In this study,the community composition and diversity of insect groups of Platycladus orientalis forest in Hangdi Mausoleum,especially litter-layer insects,were analyzed for the first time.At the same time,the occurrence range,the occurrence degree and the occurrence regularity of the main pests in ancient Platycladus orientalis forest were investigated and analyzed,and the pest comprehensive control measures were put forward.The research results have important guiding significance for the pests scientific control and ancient trees protection.The main research results are as follows:1.Studies on insect species diversity show: 14 families 40 kinds of tree trunks insects were captured,which is less quantity and insect diversity is extremely low.The main collection is litter-layer insect which belongs to 7 orders 29 families.In these specimens,Coleoptera(accounting for 59.65%)and Hymenoptera(accounting for 26.1%)were the most abundant groups.Carabidae(accounting for 33.75%),Formicidae(accounting for 25.98%)and Scarabaeidae(accounting for 14.88%)were dominant groups.Insect diversity level is closely related to the factors such as vegetation coverage,slope aspect and management meatures,etc.2.Through census and sample survey,the main pests of Pltaycladus orientalis forest in Huangdi mausoleum were identified.Poecilocoris lewisi Distant,Cinara tujafilina(Del Guercio)and Semanotus bifasciatus(Motschulsky)occurr seriously and widely.Parocneria furva Leech,Phloeosinus aubei(Perris)harm ligth and population density is small.3.The occurrence regularity of main pests were clarified by means of the forest investigation,indoor rearing,trap and sticky insect board.Poecilocoris lewisi Distant occurs 1 generation in one year and with 5 instars nymphy overwintering,climbing out of the winter site in second year April.They harm twigs leaves of Platycladus orientalis and cause black spots until the tree dead.Semanotus bifasciatus(Motschulsky)also occurs 1 generation in one year and with adults overwintering inside the tree trunk,climbing out of the winter site in second year March.They drill weak or dying trees by larva and cause trees conducting tissue damage until dry death.Cinara tujafilina(Del Guercio)occurs more than 15 generations in one year and they suck plant juices.4.Taking comprehensive measures to prevent and control pests of Platycladus orientalis forest.Chemical measures are used where the pests occur in small piece of area.The traps and biological control measures are used to control Semanotus bifasciatus(Motschulsky).Frequency trembler grid lamps are used to monitor and lure moth pests.The Poecilocoris lewisi Distant is controlled by sticky insect glue,crude oil and artificial capture method.