| Based on the meteorological data from527weather stations located in the nationalagricultural areas during1961-2010, together with the disease and pest data of the main cropsincluding wheat, maize and rice, as well as the powdery mildew and planthopper informationat province-scale, the key factors affecting epidemic disease and pests are selected to quantifythe effect of climate change on occurrence of disease and pests. Considering the occurrence ofpowdery mildew and planthopper at province-scale and its early and correspondingmeteorological factors, meteorological conditions’ level dynamic warning models of diseaseand pest occurrence would be developed in three typical regions. The main conclusions arelisted as follows:(1)In the past50years, the variations of meteorological factors are helpful to theexpansion of occurrence area and intensity of the diseases, the pests, and the disease and pests,respectively. For example, the occurrence area of the diseases, the pests, and the disease andpests would increase by156.11,60.96and96.64millionhm~2time, respectively, when theaverage temperature in the farmland areaincreases by1℃.Under proper temperature, warmingis beneficial to the occurrence of disease and pests, while high temperature is harmful. Thedecreases of less amount of rainfall and the rainfall days are beneficial to the occurrence ofdisease and pests, so do the large and heavy rainfall, while the effects of the days of large andheavy rainfall are not significant on the occurrence. Those situations including warm spring,hot summer, warm autumn and winter are beneficial to the expansion, oversummering,retention and overwintering of the occurrence of disease and pests.(2)In the past50years, the meteorological factors would result in the enhancement of theoccurrence of disease and pests for wheat, maize and rice. When the average temperatureduring the growing season of wheat increases by1℃, the occurrence area of wheat diseases,pests, and disease and pests would increase by28.54,15.35and13.19millionhm~2time,respectively.The occurrence area of maize diseases, pests, disease and pests would increase by17.37,4.96and12.41millionhm~2time respectively, when the sunshine hours decrease by100h.The occurrence area of rice diseases, pests, disease and pests would increase by174.61,57.78and116.82millionhm~2timerespectively, when the wind speed decreases by1m/s.(3)In the past30years, the meteorological factors would induce the occurrence of wheat powdery mildew,and the degree of the powdery mildew occurrence was different in differentprovinces. In general, the occurrence of wheat powdery mildew would tend to be enhanced inHenan, Hebei, Shandong, Jiangsu, Anhui and Gansu provinces, while it would be decreased inZhejiang, Fujian, Hunan and Guangxi provinces.(4)In the past30years, the meteorological factors would induce the occurrence of riceplanthopper, and the degree of rice plantthopper occurrence was difference at differentprovinces. Except of Heilongjiang province, the rice planthopper occurrence area increased inthe other provinces. In Jiangsu, Zhejiang and Hunan provinces, the occurrence area wasbeyond of2millionhm~2time, while it was between0and2millionhm~2timefor the otherprovinces.(5) Based on the factors selected by factor puffing method, meteorological conditions’level dynamic warning models of disease and pest occurrence would be developed in threetypical regions,including the meteorological conditions’ level dynamic warning models ofwheatpowderymildewoccurrence in Southwest Henan and Hebei provinces and riceplanthopper occurrence in Guilin. The predict accuracy of the three models are more than80%.These results will provide the scientific and technological support for the development of nearshort-term forecasting, and will improve the capacity of comprehensive prevention and thedecision-making service. |
