新疆盐渍化土壤氮肥氨挥发损失特征初步研究

在室温下应用“静态吸收法”,研究不同盐渍化程度的盐化土壤和碱化土壤上氮肥氨挥发损失特征。结果表明:(1)除碱土外碱化土壤上氮肥氨挥发量随时间延长呈现下降趋势,在盐化土壤上氨挥发量随时间呈现先上升后下降趋势。(2)供试9个典型盐渍化土壤样品上氮肥氨挥发量(Y)与时间(t)关系均符合Y=at2 bt c动力学方程,相关性呈极显著水平。(3)氨挥发总量(Y)、氨挥发速率(Yi)与土壤含盐量(x)呈极显著正相关;氨挥发持续时间随着盐渍化程度的增加而延长。(4)氨挥发总量、挥发速率与盐渍土pH相关性未达到显著水平;盐渍土上pH值对氨挥发的影响需要进一步研究。以上结果表明,盐渍化耕作土壤上氮肥氨挥发的控制要依据盐渍化类型的不同而制定相应的措施。

Preliminary study on the characteristics of ammonia volatilization from salinized soils in Xinjiang

A static absorbing method was used to study characteristics of ammonia (NH3-N) volatilization from alkali and saline soils of various salinization degree in room temperature. The results showed that the amount of NH3-N volatilized decreased with prolonged time in all alkalinized soils except alkaline soil, whereas in saline soil, the quantity of ammonia volatilization with time increased initially and then decreased with time. For the nine typical salinized soils, the relationship between the quantity of ammonia volatilization (Y) and the time(t) could be well described by the equation (Y=at2 bt c, r=0.84-0.99, P<0.01). The total amount and rate of ammonia volatilization (Y) were each positively correlated with the salt content in the soils. The time of ammonia volatilization was prolonged with increasing salinization degree of the soils. There was no significant relationship between the total amount and rate of ammonia volatilization and pH of the salinized soils. The effects of pH of salinized soils on ammonia volatilization merit further study. Therefore, the way of suppress the ammonia volatility lose was different with different salinization type.