| The shortage of water resources and the spatial and temporal uneven distribution of rainfall is an important problem in agricultural production in arid areas in northern China,furrow planting for rainfall harvesting system could improve soil water status, promote crop growth, improve yield and water use efficiency. This experiment was conducted to study the dynamic change of soil water temperature and winter wheat yield in winter wheat field under the flat planting（CK） and ridge and furrow planting for rainfall harvesting system（FM）, and the DNDC model was used to analyze and validate the DNDC model, and sensitivity analysis. Finally combining with the production simulation in Longxian,Qishan,Meixian in Guanzhong area, from the perspectives of yield potential to analyze the predominance of the ridge and furrow planting for rainfall harvesting system, as to provide theoretical basis for the Guanzhong region winter wheat high and stable yield.1. Soil moisture under FM treatment was significantly higher than that under CK treatment at the early stage of growing season. The results of soil temperature in 2013-2015 showed that soil temperature difference was not significant whether in 5cm or 10 cm layer. Furrow planting for rainfall harvesting system increases yield by improving soil hydrothermal condition. At jointing stage, booting stage and mature period, the dry matter under FM treatment were significantly higher than that under CK treatment. The average yield of winter wheat under FM treatment increased by 30.67%.2. Simulation results show that the simulated value and observation value were highly correlated in two processing under FM and CK treatment. The sensitivity analysis results showed, for CK, sensitivity of crop yield to the parameters from small to large was temperature, soil texture, nitrogen application amount and precipitation, However, for FM, sensitivity of crop yield to the parameters from small to large was temperature, nitrogen application amount, soil texture and precipitation, the sensitivity index of rainfall decreased from 2.19 to 1.40. The sensitivity of crop yields to precipitation was reduced. Meanwhile, FM treatment reduced the sensitivity of the crop yield to nitrogen fertilizer, it showed that the coupling effect of water and fertilizer improved nitrogen use efficiency under FM treatment.3. Using DNDC model to simulate the TPP in six sites except Heyang, Sanyuan, and compare to high-yield demonstration. The simulation value and the observation value were basicly consistent. The average production under CK treatment in eight sites in 2005-2014 was 3710-5106kg·hm-2, and the average production under FM treatment was 5954-7154kg·hm-2, the yield variation coefficients under CK and FM treatments in 2005-2014 were 0.21-0.31 and 0.11-0.18, respectively. This showed that under rain fed conditions, the production of winter wheat under flat planting was low, and yield fluctuation was large, it was difficult to obtain high and stable yield, under ridge and furrow planting for rainfall harvesting system, the yield increased at the same time, the fluctuations of annual yield was smaller.Average moisture requirement rate under CK treatment was 0.42-0.56 and average moisture requirement rate under FM treatment was 0.68-0.79 in eight sites in 2005-2014, The variation coefficients of moisture requirement rate under CK and FM treatments were 0.18-0.29 and 0.09-0.17. Due to the difference between annual precipitation, the yield increased by 1.6%-156% under ridge and furrow planting for rainfall harvesting system. Yield-increasing effect in Less rainfall year was higher than that in more rainfall year. |
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