摘要
本文引入模糊集论中基于模糊等价关系的模糊聚类的分析方法,将发病数量(病害强度)、空间和时间动态的相互关系联系起来,作为统一体,研究了杨树灰斑病(Coryneum populinum Bres)的流行动态,以平均病情指数((?))、聚集度指标((?)/M)和病叶率(p)作为群体动态的特征量度,将对病害流行系统的考察化成对若干亚系统(若干阶段)来研究,使复杂的系统得以简化。同时对该病短期预报、中期预报进行了研究,建立了短期和中期预报方程。
A new method for studying the epidemic dynamics of forest tree disease by means of Fuzzy theory.was mentioned in this paper,Connecting the interrelations between the disease intensity and dynamics of space and time as an integrated research object, the authors studied the epidemic dynamics of grey spot of Populus simonii×nigra. (Cory……) The average disease index, the index of the patchiness (M/M) and the percentage of the infected leaves were caused as the characteristic measures of community dynamics. Dividing the epidemic system of the disease into sereral subsystems to make it simpler.
At the same time the prediction of the disease has been studied and the short and mid-period model equations were established as following:
The short-period one is Y = 2. 9777 + 1. 0730X_1 + 0. 0073X_8 -0. 3843X_4
The mid-period one is Y = 5. 3457 +0.7483X_1 +0.0029X_8+ 1.1523X_4
The above two prediction equations were available through examining the disease indices in practical survey.
出处
《林业科学》
EI
CAS
CSCD
北大核心
1990年第5期419-426,共8页
Scientia Silvae Sinicae
关键词
小黑杨
灰斑病
模糊聚类
流行
杨树
Grey spot of populus simonii×nigra
Epidemic dynamics
Fuzzy clustering
Prediction
