The Research Of Carbon Dioxide Emission And It's Changing Rule Under Different Fertilization In Spring-Corn Farmland

This thesis studied the soil CO₂ emission changed with corn growth in different influence facts and different fertilizer management in corn farmland and indoor experiment. The main results of experiment are as follow:1. The measure of soil CO₂ emission in different corn growth phrase shown that soil CO₂ emission is related with corn growth phrase, it is because the change of foots and microbes in different growth phrase. It can be revealed through the farmland experiment. The amount of soil CO₂ emission changed with the corn growth phrase. The farmland emits the highest amount CO₂ when the corn growth is in the best growth phrase.2. The fertilization influenced the amount of soil CO₂ obviously. The growth of the amount of CO₂ emission followed the growth of organic fertilizer and nitrogen fertilizer. It is because of the grow condition of corn roots and soil microbe activation. The organic fertilizer also increased the amount of carbon leading to emit more CO₂ gas. The indoor experiment show the when the rate of C/N is about 15, the CO₂ emission gets it's highest amount.3. The amount of CO₂ emission is related with temperature, when the temperature changed in corn growth Course, the amount of CO2 emission changed with it. 21st in July, the temperature is the highest, at the same time, the amount of CO₂ emission in a day is the highest too, the same result is gotten in indoor experiment. The temperature is a main influence fact and the amount of CO₂ emission is direct rate to temperature. The soil humidity isn't direct related to the amount of CO2 emission except the soil too dry or wet.4. The size of soil particle is tightly related to soil CO2 emission, when the diameter is between 0.15mm- 1mm, the amount of soil CO₂ emission is decreased with the diameter diminishing, the soil of the least size emitted the least amount CO2, it's because little hole hold up the gas emission and reduce the speed of breaking down of organic material. But when the diameter of soil particle is big excessively, the amount of CO2 decrease too, it's because of the low amount of organic material in big size soil particle and the low continuance of CO₂ emission.5. The experiment through analyzing the changing regulation of corn yield, organic material and nitrogen amount in different fertilizer management, shown that the corn yield increased obviously and the organic material, total nitrogen and available nitrogen increasea little in condition of fertilization while they decrease in condition of no fertilization, that's mean that fertilization is a effective measure to keep the fertility of land.