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应用Stanford&Smith间歇淋洗好气培养法,对安徽淮北地区砂姜黑土进行了170 d的矿化培养,研究温度、C/N比对玉米秸秆粉碎还田土壤氮素矿化过程的影响,并运用动力学模型(One-pool模型、Two-pool模型、Special模型)对试验结果进行了拟合。结果表明,各方程模型均达到显著或极显著水平。Two-pool模型(两部分一级反应式)和Special模型(带常数项的一级反应式)拟合程度均高于One-pool(一级反应式)模型,说明有机氮素库分为易矿化氮源和缓慢矿化氮源,能更切合实际地反映土壤氮素矿化特征。One-pool模型中,土壤氮素矿化势No值随温度的升高而增大,在同一温度条件下,加入作物秸秆量越大,即C/N比越高,No值越大。矿化速率Ko值和C/N比密切相关,在同一温度条件下,C/N比增大Ko值降低。Two-pool模型中可以看出,温度显著影响有机氮的矿化,较高温度条件下,易矿化氮源Na值比低温条件下高。
The Stanford & Smith intermittent leaching aerobic culture method was used to mineralize sago black soil in Huaibei area of Anhui Province for 170 days to study the effect of temperature and C / N ratio on soil nitrogen mineralization process of maize stalk returning to soil. The experimental results were fitted using the One-pool model, the Two-pool model, and the Special model. The results show that each equation model reached significant or very significant level. The two-pool model (two-part first-order reaction) and the Special model (first-order reaction with constant term) fit better than the One-pool model, indicating that the organic nitrogen pool is easily The mineralized nitrogen source and slowly mineralized nitrogen source can more accurately reflect the characteristics of soil nitrogen mineralization. In the One-pool model, the No value of soil nitrogen mineralization increased with the increase of temperature. Under the same temperature conditions, the greater the amount of crop straw added, the higher the C / N ratio, the greater the No value. Mineralization rate Ko value and C / N ratio are closely related to the same temperature conditions, C / N ratio increases Ko value decreases. In the Two-pool model, it can be seen that temperature significantly affects the mineralization of organic nitrogen. Under higher temperature conditions, the Na value of the easily mineralized nitrogen source is higher than that at low temperature.