Study On Occurrence And Trend Of Forest Fire In Beijing Area

Based on the historical and meteorological data of forest fires during the fire prevention period in Beijing in 2007-2016,this study used SPSS,ArcGIS and R project statistical analysis software to study the temporal and spatial distribution of forest fires in the region and explored forest fires.The relationship between meteorological factors and the occurrence of forest fires in Beijing is established,which provides an important reference for forecasting and forecasting forest fires.The main findings are as follows:(1)Analysis of the temporal and spatial distribution of forest fires during the period of fire protection in Beijing in 2007-2016 shows that forest fires in Beijing are mainly caused by human factors,especially charcoal burning and tobacco smoking in the wild.On the time scale,2007 was the most frequent occurrence of forest fires,and the number of forest fires fluctuate year by year.The 2-4 months of each year are the peak period of forest fire,and the timing of the day of forest fire changes obviously.Most of them occur from about 10 a.m.to about 20 p.m.,especially at 14-15 p.m.most.(2)On the spatial scale,the forest fire high-incidence areas are mainly distributed in areas below 400 meters above sea level,and rarely occur in areas above 1200 meters.The number of forest fires in Beijing has increased from west to east,and from north to south in latitudes.The rate of forest fire control has decreased first and then increased from southwest to northeast.(3)Analyzing the correlation between meteorological factors and forest fire occurrence,we can see that the occurrence of forest fire has a significant correlation with monthly average relative humidity,monthly average wind speed,and monthly sunshine hours,and a single linear model is used to determine the number of forest fire occurrences and significant related meteorological factors.Fitting,the results show that the model has good applicability in the case of small changes in the number of forest fire occurrences.(4)Using NB model and ZINB model to fit the relationship between forest fire occurrence and monthly average temperature,monthly precipitation,monthly average relative humidity,monthly average wind speed,and monthly sunshine hours,and the fitting results are better..The two models were tested and the results showed that the prediction results of ZINB model are more in line with the actual forest fire occurrence in Beijing.The monthly mean temperature,monthly mean relative humidity,and monthly average wind speed are important meteorological factors affecting the occurrence of forest fire in Beijing.(5)Take Yanqing District and Miyun District as an example,predict the number of forest fires through the ZINB model,and obtain the forest fire occurrence index and gradation zoning in the region.The results show that the maximum predicted values of the two districts all appeared in April,and the fire risk index in both Yanqing and Miyun districts remained high.These two districts were high fire risk grades throughout the fire protection period,especially in the 2-4 months.The fire risk index shows an increasing trend.