| Under the influence of global climate change,the shortage of water resources and climate warming are serious problems that China is facing.Studies have confirmed that the environmental stress under the background of climate change is increasing the instability of China’s agriculture.The growing time of winter wheat is long,and the climate and environment are different during the growing period,especially the temperature and water during the filling period.Because of the wide range of winter wheat production and planting in China,it is very important to carry out the research on climate change in its later growth period.WOFOST model has strong mechanism and practicability,and is widely used in the research and application of winter wheat growth and development in different regions.It is of great significance in yield evaluation and decision-making of agricultural measures.Based on the historical meteorological data,soil data and winter wheat growth period data of three typical meteorological stations: Xuzhou,Huai’an and Changzhou,the WOFOST crop growth model was used to simulate and analyze the effects of warming and drought on winter wheat yield,aboveground dry matter weight and dry matter distribution in Jiangsu Province,The details are as follows:(1)Before applying WOFOST model to the actual research in Jiangsu Province,the sensitivity analysis of parameters was carried out,and the crop and soil parameters of each site were determined by adjusting parameters,so as to realize the localized use of the model.In this study,the initial variable perturbation method was used to analyze the sensitivity of the parameters,and the parameters were adjusted and verified according to the sensitivity and range of the parameters,combined with the actual situation of Winter Wheat in Jiangsu Province.Finally,the relative root mean square error of winter wheat yield simulation of the three stations is controlled within 10%,which meets the simulation accuracy requirements,and the model can be used for subsequent simulation.(2)In order to simulate drought and warming stress,the precipitation and temperature anomaly index of three stations in 10 years(2008-2017)were calculated,and the relative deviation of winter wheat yield in 10 years was combined.The normal and non drought years were selected as the base year: Xuzhou in 2014,Huai’an in 2010,Changzhou in 2009.(3)The WOFOST model was driven by the actual meteorological conditions of the base year in Jiangsu Province,and the yield index of the base year was obtained;From the beginning of grain filling period,the treatments of daily warming(1 ℃,2 ℃,3 ℃),drought(mild,moderate,severe)and their combined stress were carried out for 30 days,and the total above ground production(TAGP)and total dry weight of stored organizations(TWSO)were simulated,By analyzing the yield reduction rate and dry matter distribution(the ratio of TWSO and TAGP)of relative standard yield under different treatments,the effect of increasing temperature and drought on yield formation of winter wheat was discussed.(4)The simulation results showed that both single stress and combined stress could reduce the yield of Winter Wheat in Jiangsu Province to a certain extent,and all kinds of stress could inhibit the distribution of dry matter in grains and reduce the accumulation of dry matter in aboveground parts of winter wheat.On the whole,the indexes under combined stress were more affected than those under single stress.The increase of temperature had the greatest impact on the yield reduction in southern Jiangsu,and the dry matter accumulation in the aerial part of Southern Jiangsu was most seriously hindered,and the impact on the dry matter accumulation in the aerial part increased from north to south;The yield of Winter Wheat in the middle part of Jiangsu Province was most seriously affected by drought,and the influence degree of dry matter weight of aboveground part and dry matter distribution of grain decreased from south to north.Under the combined stress,the yield reduction rate of winter wheat increased with the increase of the total stress degree,and the aboveground dry matter weight decreased with the increase of the stress degree.Under the combined stress of warming and drought,the yield reduction rate of Winter Wheat in the middle of Jiangsu Province was on the high side.Under other combined stresses,the yield reduction rate gradually decreased from the south to the north of Jiangsu Province.Meanwhile,the total aboveground dry matter weight gradually increased from the south to the North,and the grain dry matter distribution was lower in the South than in the north than in the middle of Jiangsu Province. |
PDF Full Text Request