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利用相关性分析和主成分分析的方法,分析了冰核细菌溃疡病发生特点与环境条件的之间的关系,选出了影响杨树病害发生的主要影响因子。同时综合分析病害流行的主因和诱因,提出东北地区杨树冰核细菌溃疡病危险等级划分标准,并将东北地区分为重发区、常发区、偶发区和安全区4个不同等级冰核细菌溃疡病发生区。6种模型曲线的非线性回归分析表明,冰核细菌溃疡病流行的时间动态以理查德生长模型为最优生长模型。运用逐步回归分析方法,建立了多元线性的中期预报方程,可以预测第二年的病情指数。根据病情指数随时间增长的趋势,选用灰色方法建立GM(1,1)数学模型,可做出中长期预报。
By using the method of correlation analysis and principal component analysis, the relationship between the characteristics of ice-seed bacterial ulcer disease and environmental conditions was analyzed, and the main influencing factors that affected the occurrence of poplar disease were selected. At the same time, the main causes and inducing factors of epidemic of diseases were comprehensively analyzed, and the classification criteria of poplar ice nucleation ulcer disease risk in northeastern China were put forward. The northeast area was divided into 4 different grades of ice nucleus bacterial ulcer of recurrent area, frequent area, sporadic area and safe area Disease area. The non-linear regression analysis of the six model curves showed that the temporal dynamics of the development of ICE can be best modeled on the Richard growth model. By using stepwise regression analysis method, a multivariate linear medium-term forecasting equation is established, which can predict the disease index in the second year. According to the trend of the disease index increasing with time, the GM (1,1) mathematical model is selected by gray method to make mid-long term forecast.