Study On The Present Situation Of Natural Hazards And The Types Of Main Insects In Pinus Tabulaeformis In Luliang Mountain Area, Shanxi Province

The aim of the study is to analysis the damage ratio of seed by four different forest structures and four different slope-exposure. we use five index[population density(CK)、damage ratio of cone(QG)、 damage ratio of seed (ZZ)、yield damage of seed (CL)and standing crop(XC)] to evaluate the damage ratio of seed. QG、ZZ、CL and CT was to the lowest index among the broad-coniferous forest, however CK、QG and XL were the highest in shrub-mixed forest; CK、QG、ZZ and XC was the biggest in sunny slope, but in the secondary shade slope,the CK、QG and ZZ was the lowest.there were discrepancy between the forest structure and the slope.The main insect pests of seed and cone of main insect pests are Pyralididae、Noctuidae、Scolytidae and Curculionoidea respectively at the base of situations of damage. The change of the number of Pinus bungeana forest is the biggest in the four main insect pests in the structure of Pinus bungeana forest; The difference of numbers of Pyralididae is obvious at the scale of shade density, Noctuidae is more obvious, but Scolytidae and Curculionoidea is not obvious. the effect of the slope of the site in the Pinus bungeana nature forest is not obvious in the numbers of individuals, reside of Curculionoidea. The study is to protect management seed and cone of the Pinus bungeana nature forest and provide information about succession of the Pinus bungeana nature forest.