Occurrence Prediction of Pine Wilt Disease Based on CA-Markov Model

Pine wilt disease (PWD) has become a devastating disease that impacts China's forest management. It is of great significance to accurately predict PWD on a geospatial scale to prevent its spread. Using the Cellular Automata (CA)-Markov model, this study predicts the occurrence area of PWD in Anhui Province in 2030 based on PWD-relevant factors, such as weather, terrain, population, and traffic. Using spatial autocorrelation analysis, direction analysis and other spatial analysis methods, we analyze the change trend of occurrence data of PWD in 2000, 2010, 2020 and 2030, reveal the propagation law of PWD disasters in Anhui Province, and warn for future prevention and control direction and measures. The results show the following: (1) the overall accuracy of the CA-Markov model for PWD disaster prediction is 93.19%, in which the grid number accuracy is 95.19%, and the Kappa coefficient is 0.65. (2) In recent 20 years and the next 10 years, the occurrence area of PWD in Anhui Province has a trend of first decreasing and then increasing. From 2000 to 2010, the occurrence area of disasters has a downward trend. From 2010 to 2020, the disaster area has increased rapidly, with an annual growth rate of 140%. In the next 10 years, the annual growth rate of disasters will slow down, and the occurrence area of PWD will reach 270,632 ha. (3) In 2000 and 2010, the spatial aggregation and directional distribution characteristics of the map spots of the PWD pine forest were significant. In 2020 and 2030, the spatial aggregation is still significant after the expansion of the susceptible area, but the directional distribution is no longer significant. (4) The PWD center in Anhui Province shows a significant trend of moving southward. From 2010 to 2020, the PWD center moved from Chuzhou to Anqing. (5) PWD mainly occurs in the north slope area below 700 m above sea level and below 20 degrees slope in Anhui Province. The prediction shows that the PWD disaster will break through the traditional suitable area in the next 10 years, and the distribution range will spread to high altitude, high slope, and sunny slope. The results of this study can provide scientific support for the prevention and control of PWD in the region and help the effective control of PWD in China.