Evaluating The Impact Of Procneria Orienta Chao's Injury On Cupressus Funebris Forest's Health

Parocneria Orienta Chao is the most primary leaf pest in the Sichuan Cupressus funebris' shelterbelt. Recently, it might disserve 430,000 hm² annually, which badly threaten the constructed production of shelterbelt on Middle and Upper Reaches of the Yangtze River. The researches on the index of prevention and cure were merely in the last century 80's just on volume.First, In order to study on the connection of the quantity of Cupressus funebris' leaves and diameter at breast height, the sample was chose to pick off leaves. It was manifested that the quantity of leaves increasing followed the diameter at breast height. The connection extrend to exponential regression, M=ae^Bd. Through the data processing, the equation is M=2323.7261 e^0.124455D. The impact of different picking intensity on Cupressus funebris' diameter at breast height (D), height (H), volume (V) have been mensurated. It was indicated that the bigger picking intensity, the less volume growth, the more height increasing. When the intensity of picking off leaves was respectively 90%,60%,30%,0%, the hardly any difference in each diameter at breast height, but the distinct difference in each volume have been analyzed by Duncan statistic analysis. The result analyzed by DPS statistic software was that, the relation of losing leaves intensity (X) and volume growth (Y) was a parabola. The equation was Y=0.007018-0.000726X-0.005216X². The equation of losing leaves intensity (X) and volume losing (Y') was Y'=0.000726X＋0.005216X².Second, the research in runoff manifested that the corresponding equations could be founded with intensity picking off leaves as independent variable and the quantity of bedload as a cause variable. The conic model is Y=ax²ï¼‹bx＋c. However, according to crown interception, the equation Y=a＋be^cx could be founded about different intensity picking off leaves as independent and crown interception as a cause variable.Third, the result of social investigation in experiment plot and surrounding Cupressus funebris forest indicated that the appraise index about that Parocneria Orienta impact the health of Cupressus funebris on the sight value.Ultimately, the each appraise index about that Parocneria Orienta impact the health of Cupressus funebris could result from expert judgement. The index I equal to 37.6976%. I means the biggest limit of Cupressus funebris to the damage of Parocneria Orienta. It also meas the control index of Parocneria Orienta is 37.6976%. On the basis of model about the quantity of Cupressus funebris' leaves, it could obtain that the each control index was 441, 565, 725, 930 insects per tree of average diameter at breast height at 8cm, 10cm, 12cm, 14cm.