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Study on Water Use Efficiency of Summer Maize Based on Crop Growth Simulation Model in North China

Author: XingKaiZuo
Tutor: JingYuanShu；MaYuPing
School: Nanjing University of Information Engineering
Course: Applied Meteorology
Keywords: Crop growth simulation models Water use efficiency Space-time transformation
CLC: S513
Type: Master's thesis
Year: 2011
Downloads: 123
Quote: 0
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Abstract

Summer corn is one of the main crops of the North China region, have important significance on the national corn production. North China during the summer maize growing, although every rainy season, but precipitation variability, and thus the different time scales of drought still frequently occur. Combined with irrigated area expanded and intensified conflicts between industrial and agricultural water, agricultural water shortage problems have become increasingly prominent. To this end, we need to clarify the crop growth and yield formation and the relationship between the consumption of water resources. Water use efficiency is an important parameter to study the relationship between crops and water, is an important way to coordinate high-yield and water consumption in contradiction. The foreign crop growth models WOFOST the adaptation, and to try to improve moisture stress on summer corn dry matter allocation process model, discussed description corn water use efficiency using WOFOST model approach, and base carried out in North China summer maize water use efficiency simulation study, the analysis of the spatial and temporal variation of the water use efficiency. The main conclusions are: (1) the use of the measured data, default values, and trial and error to determine the value of the growth parameters of WOFOST model; distribution characteristics according to representatives of the North China site development parameters space, combined with the topography, and in the light of our corn the climatic zoning Results determine developmental the partitions and value of the parameter. Partition and values ??of the soil parameters are determined based on the soil type map. The simulation test show that the the basic WOFOST model to reflect the process of growth and development of the North China summer corn farmland soil moisture dynamic localized and regional application of the model WOFOST. (2) the use of the field trial data initially established a sub-mode of water stress distribution of dry matter. The simulation test found, to join the sub-mode to the spike weight WOFOST to simulate the effect of a slight improvement, but no significant improvement biomass and soil moisture dynamic simulation, further studies are needed. Total assimilation rate, transpiration rate, and water stress under production conditions (3) the use of the model to simulate the WOFOST potential CO2 storage organ dry weight, total dry weight of the ground, transpiration and evaporation leaves, groups and different levels of yield defined water use efficiency. (4) summer maize in North China GASS water use efficiency WUE1 with the development process slightly decreasing trend, but generally small changes: the relating to TAGPw ??WUE2 WUE3 basic trend line gradually increased in the early stage of corn development , before and after silking maximum, and then gradually decreases; a WSO related WUE4 WUE5 trend is also basically the same, and maintained at a higher level in the 1.3 to 1.8 In the DVS. Water use efficiency of the region-wide average decadal change is small, only slightly higher than in the 1980s, and decadal variability of water use efficiency in different regions of North China is even more obvious. The study showed that corn water use efficiency is primarily related to net primary productivity, LAI is decided with the developmental changes in the main factors of water use efficiency. (5) North China summer maize water use efficiency is presented in space on the form of the distribution of the Matter. Summer maize water use efficiency is the most obvious difference between north and south in the 1960s, In 1970s southern North China improved to some extent, in the north of Beijing and Henan provinces in the northern region continued to improve in the 1980s, the North Central Region decreased since the 1990s. The efficiency of water use in the space on the form of the distribution is mainly affected by the ground affect total dry weight.

Study on Water Use Efficiency of Summer Maize Based on Crop Growth Simulation Model in North China

Abstract

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