基于DNDC玉米种植条件下土壤温室气体排放研究

Study on Soil Greenhouse Gas Emission Based on DNDC Corn Planting Condition

为了探究山西省太谷县玉米种植情况下整个年份土壤的排放规律,应用2016年太谷县气象、土壤和玉米种植数据,利用参数本地化后的DNDC模型模拟2016年玉米生长整年的排放。结果表明,土壤碳排放发生变化主要是在种植玉米后,尤其是在玉米收获后,土壤碳排放在一定时间内呈上升趋势,一年内土壤碳排放呈现平稳—上升—降低的趋势;土壤氮排放随着作物生长而发生变化,作物生长期的氮排放较非作物生长期提高94%,排放峰值出现在作物生长后期,10 d累积氮排放量最高达0.084 kg/hm2;环境排放与施肥量呈正相关,其中,标准施肥量(1 050 kg/hm2)下硝酸盐排放是高施肥量(2 100 kg/hm2)的35%,且施肥量越高,硝酸盐淋洗量越高。

To explore the soil discharge law of the whole year under the corn planting situation in Shanxi province Taigu county, this paper applies meteorological data, soil data and maize planting data of Taigu county in 2016, and uses the parameterized localized DNDC model to simulated annual emissions of maize growth in 2016. The research results show that the change of soil carbon emissions is mainly after the corn planting. Especially after corn harvest, soil carbon emissions show an upward trend in a certain period of time. Soil carbon emissions show a steady-raising-decreasing trend throughout the year. Soil nitrogen emission changes with crop growth, and nitrogen emissions during crop growth period are 94% higher than those during non-crop growth period. The peak of emission occurs in the late stage of crop growth, and 10 d cumulative nitrogen the highest emissions are 0.084 kg/hm^2. Environmental emissions are positively correlated with fertilization. Among them, nitrate emission under standard fertilization(1 050 kg/hm^2) is 35% of that under high fertilization(2 100 kg/hm^2), and the higher the amount of fertilizer applied, the higher the amount of nitrate leaching.