Research Of Climatic Resources, Suitability And Potential Productivity For Winter Wheat In Huang-Huang-Hai Region Under A1B Climate Scenario From RegCM3

Based on winter wheat growth period data of 91 agricultural meteorological stations in Huang-Huai-Hai winter wheat region in 1991-2013 and daily meteorological data of 100 weather stations in the corresponding years, grid accumulated temperature index was used to divide growth period, combining with daily meteorological data of 100 weathers stations in Huang-Huai-Hai winter wheat region in 1971-2000 and daily 0.25x0.25 degree gridded meteorological data under A1B climate scenario(1951-2100)extracted from the regional climate model RegCM3 by the National Climate Center, variation characteristics of mainly climatic factors in Huang-Huai-Hai winter wheat region under climate change, the effects of climate change on agroclimatic resources in winter wheat growth period, climatic suitability and climatic potential productivity were analyzed. The aim was to supply theoretical basis for dealing with climate change, reasonable utilization of agricultural resources and adjusting agricultural structure. The main results were as follows:(1) In 1951-2100, the annual temperature and the accumulated temperature of 0℃ all showed increasing trends obviously from time and higher in the south than the north from space. It was present a gradually decreasing trend in 1951-1980, more obvious after 1981; Inter-annual fluctuation of precipitation was larger, generally present a fluctuating trend of decrease-increase-decrease-increase from time, increasing from northern to southern from space and increasing more obviously in the north. The optimum sowing date showed a gradually delayed trend from northwest to southeast in space and also from time. The growth season length of winter wheat showed a gradually extended trend from south to north from space and gradually shortened from time. The precipitation in winter wheat growth season decreased from southwest to northeast from space but not obviously from time. Reference crop evapotranspiration in winter wheat growth period decreased after increased from south to north from space and gradually decreased trend from time. The radiation in winter wheat growth period showed a gradually increasing trend from south to north and gradually decreasing from time.(2)In future climate warming, the temperature suitability of winter wheat in the whole growth period in Huang-Huai-Hai winter wheat region showed a gradually increasing trend in north, as time went by thermal condition was more beneficial to winter wheat growth in the north, however its was decreasing after increasing in the south; the temperature suitability of winter wheat in each period maintained between 0.65-0.85, the coefficient of variation was gradually decreasing, global warming still had a positive effect on temperature suitability in Huang-Huai-Hai winter wheat region. The precipitation suitability of winter wheat in the whole growth period in Huang-Huai-Hai winter wheat region was higher in the west and south and lower in central and northeast from space, decreased after increased from time, which was basically consistent with precipitation in winter wheat growth period; but the inter-annual fluctuation was larger, water resource was still the main factor which restricted the stable yield of winter wheat in Huang-Huai-Hai winter wheat region. The sunshine suitability of winter wheat in the whole growth period showed a gradually decreasing trend from northeast to southwest and increasing after decreasing then decreasing from time. Sunshine suitability was high; its coefficient of variation showed a decreasing trend from time, fluctuating decreasing sunshine suitability might bring negative effects on climatic suitability. The climatic suitability of winter wheat in the whole growth period generally showed a distribution characteristic of higher in southeast and north and lower in southwest and center, the decadal coefficient of variation fluctuated from time, except a slightly increase in 1981-2010.(3)The winter wheat climatic potential productivity in Huang-Huai-Hai winter wheat region showed a fluctuant decrease trend from the inter-annual variation, and the trend gradually stabilized; the winter wheat climatic potential productivity varied between 6277～7044 kg·hm-2, except the rise of 21.94 kg·hm-2·10a-1 in 2011-2040, presented a downward trend during other periods in Huang-Huai-Hai winter wheat region; winter wheat climatic potential productivity was lower in the north and higher in the surround from space, smooth before gradually reduce from time, the coefficient of variation showed a gradually increase trend from the south to the north from space, firstly increases and then decreases in northern and firstly decreases and then increases in southern from time. The match of water, light and temperature should be paid more attention during the growth period in the practical production process.