Effects Of Warming And Different Types Of Soil On Wheat Yield And Quality

In order to reveal the response of wheat growing in different soil types to elevated temperature,a spatial transplant experiment was conducted at the Agrometeorological Experimental Station of Nanjing University of Information Science and Technology.The Free Air Temperature Increased(FATI)was used to mimic elevated temperature during whole wheat growing season.The studied soils were sampled from Phaeozem,Burozem,Aeolian sand soil,Loess,Yellow brown soil,Purple soil,Sierozem,Vertisol,Saline-alkali soil,Fluvo-aquic soil,Krasnozem and Latosol zone.After harvest,the relevant indicators such as wheat yield and quality,mineral elements,soil enzyme activity and soil basic nutrients are measured.Based on the above indicators,the following conclusions are drawn.1)Compared to the ambient temperature treatment,the elevated temperature treatment significantly reduced the concentrations of soil water,available phosphorus and available potassium by 19.11%,9.82% and 5.35%,respectively.There was no obvious effect on soil available nitrogen.Elevated temperature significantly increased the activities of soil Invertase and Urease by 26.36% and 13.96%,but significantly reduced the activities of soil Phosphatase and Catalase by 8.57% and 9.07%.The correlation results showed that the activities of Urease,Phosphatase and Catalase were significantly positively correlated with p H;Invertase and Phosphatase were significantly positively correlated with soil available nitrogen;Urease,Catalase and available potassium were significantly positively correlated.2)Elevated temperature significantly increased wheat plant height,ground dry weight and yield by 11.41%,28.28% and 22.91%.The maximal impact of elevated temperature on wheat plant height occurred in yellow brown soil with an increase of 14.46%;the manimal impact occurred on saline soil with an increase of 9.11%.This might be due to the different adaptability of wheat grown in different types of soils to elevated temperature,resulting in obvious variance in the above-ground dry weight and yield of wheat.Under increased temperature condition,the ground dry weight and yield of wheat grown on Aeolian sand soil,Loess,Yellow brown soil,Sierozem,Krasnozem and Purple soil increased significantly,but the above-ground dry weight and yield of wheat grown on Phaeozem were inhibited.The correlation analysis showed that the changes in the number of effective spikes,grains per spike and 1000-grain weight were the main factors for changes in wheat yield in response to elevated temperature.3)Elevated temperature significantly increased the N and P content of wheat grains by20.75% and 3.97%,but significantly reduced the K content of wheat grains by 15.99%.Elevated temperature significantly increased the N,P,and K content of wheat straw by14.79%,69.33% and 11.41%,respectively.Elevated temperature can significantly change the absorption of trace mineral elements in wheat grains.Elevated temperature significantly enhanced the absorption of trace mineral elements Zn,Fe,Mn and Ca by wheat grains,and the increase rates were 39.69%,21.87%,44.51% and 14.75%,respectively.4)According to principal component analysis,21 indicators for evaluating wheat yield,quality and soil fertility can be condensed into 6 principal components.The results of the comprehensive evaluation showed that the comprehensive evaluation value(D value)of the treatment of Phaeozem at elevated temperature was the largest,which was 0.750,indicating that the black soil has a great potentiality for improving wheat yield,quality and soil fertility under increased temperature conditions.Through the cluster analysis of the D value,the comprehensive quality of wheat grown on different treatments and different soil types can be divided into four categories.The study of D worth shows that temperature increase has a greater effect on the overall quality of wheat grown on Fluvo-aquic soil,but has a poor effect on the overall quality of wheat grown on Latosol.