Study On The Difference Of Occurrence Regularity Of Eogystia Hippophaecolus Under Different Forest Conditions

According to the results of this experimental study and the long-term forestry practice,hippophae natural forest and hippophae artificial pure forest will suffer from erosion of Eogystia hippophaecolus.However,the natural forest of hippophae does not cause large-scale outbreaks of insects,but the artificial pests of hippophae artificial forest will be more serious,causing great damage to hippophae plants,which seriously affects the growth and development of hippophae.The occurrence of Eogystia hippophaecolus disasters and artificial pure forests will cause large-scale outbreaks and spreads.The causes of the disasters are formed in many ways,including the effects of natural environmental changes(such as less precipitation,dry climate,and poor site conditions).There are also physiological reasons(such as large age,weak tree)caused by changes in the growth rhythm of hippophae plants,as well as human factors(such as improper forest management and single species).This paper mainly studies the difference of hippophae tree,the difference of soil moisture content and the difference of environmental conditions,and analyzes the main factors affecting the difference and the difference of Eogystia hippophaecolus,under different forest management methods and site conditions.The following are the results of the study:There are significant differences in plant height,ground diameter and crown width of hippophae under different site conditions.The plant height,ground diameter and crown width of hippophae in river valley are larger than that of hippophae plant height,ground diameter and crown width.There are also significant differences in plant height,ground diameter and crown width between different forest management methods,namely natural mixed forest,natural pure forest and artificial pure forest.There were significant differences in the canopy closure degree of hippophae under different site conditions.The canopy closure degree of the river valley was greater than that of the slope.There were significant differences in the canopy density of the hippophae forest under different forest conditions,and the natural forest was closed.The plantation has a small degree of canopy closure,and the natural mixed forest is more closed than the natural pure forest.There is a significant difference between the soil water content of the valley and the soil water contentof the slope land,and the soil water content of the river valley is greater than the soil water content of the slope land;the soil water content of the hippophae natural forest and the hippophae plantation is significantly different,and the soil water content of the hippophae natural forest is higher.Large,plantation soil moisture content is small,and natural mixed forest and natural pure forest soil water content is also significantly different,natural pure forest soil water content is higher than natural mixed forest.There were significant differences in the rate of insects under different site conditions.The rate of insects in river valleys was less,and the rate of insects on slopes was larger.There were significant differences in the rates of different planting systems,and the rate of insects in natural forests was higher.Less,the rate of insects in plantations is higher;the number of adults in different site conditions is not significantly different,there are significant differences in the occurrence of different forest pests,and the incidence of natural forest pests is less than that of plantations.The main factors affecting the difference of Eogystia hippophaecolus are soil moisture content,altitude and canopy density.There is a negative correlation between the occurrence of insect damage and the canopy density of the forest,and a positive correlation with altitude,and soil.There is a positive correlation between water content.