重庆市水稻病虫害的时间分布规律与重灾年份预测研究

Study on temporal distribution and trend prediction of rice plant diseases and insect pests in Chongqing Municipality

水稻是重庆市的第一大粮食作物,频发的水稻病虫害始终是制约重庆水稻种植业可持续发展的障碍因素。利用重庆市1950-2013年的水稻病虫害发生面积、水稻实际损失和水稻播种面积资料,采用数理统计分析方法、小波分析法和灰色灾变预测模型分析了水稻病虫害的时间分布规律和演变趋势。分析表明:在研究时段内,重庆市水稻病虫害总体呈增长态势,尤其是20世纪80年代初之后,呈现发生范围广和损失增大的趋势,这表明水稻整体的抗灾能力的不稳定性。水稻病虫害发生率和受损率具有特别显著的同步性特点,表明水稻病虫害致灾能力强;小波分析显示重庆市水稻病虫害受损率异常指数存在着准8年和23年的振荡周期,水稻病虫害发生率异常指数存在着准14年和23年的振荡周期;水稻病虫害灰色灾变预测结果表明,2014-2033年将出现4个重灾年份,可能出现在2015-2016、2018-2023、2025-2026和2028-2031年期间。这将为重庆市水稻病虫害的防灾减灾提供参考。

Rice is the first major food crops in Chongqing Municipality. Rice planting industry sustainable develop- ment in Chongqing Municipality is always restricted by frequent rice plant diseases and insect pests. Based on the rice plant diseases and insect pests occurrence area, actual rice loss and rice planting area in Chongqing Municipal- ity during 1950 -2013, the time temporal distribution and the evolution tend of rice plant diseases and insect pest disasters was analyzed by using the mathematical statistical analysis method, wavelet analysis method, and the gray system prediction model. It can be seen from the analysis that, rice plant diseases and insect pest disasters in- creased in the research period. Great disaster, influenced area and losses increased evidently after the early 1980. This indicated that, the resistance capacity of rice was not stable. The damage rate of rice plant diseases and insect pest disasters was synchronous with the incidence rate of rice plant diseases and insect pest disasters. It showed that, rice plant diseases and insect pest disasters could easily cause disaster once it happens. Wavelet analysisshowed that, the oscillation periods of rice plant diseases and the damage rate anomaly index of insect pests in Chongqing Municipality were quasi 8 and 23 years, and the oscillation periods of rice plant diseases and incidence rate anomaly index of insect pests in Chongqing Municipality were quasi 14 and 23 years. A grey system prediction model was established according to the changes of anomalous indices. Grey modeling results showed that, there would be four periods of great rice diseases and insect pest disasters from 2014 to 2033, which would be during 2015 -2016,2018 -2023,2025 -2026 and 2028 -2031 respectively. This study would provide a reference for dis- aster prevention and mitigation of rice plant diseases and insect pests in Chongqing Municipality.