蒸渗仪控制下烤烟土壤水分的时空动态研究

采用蒸渗仪试验,研究了不同水分处理下烤烟土壤水分时空动态变化。结果表明,全生育期0～20cm土层水分含量变化最为活跃,20～40cm土层次之,40～60cm土层较为稳定;建立了不同土层土壤含水量随时间变化的数学模型,以此来推测烤烟土壤水分随时间的变化动态;烤烟伸根、旺长、成熟期的计划湿润层深度分别以20～30cm,50～60cm,30～40cm较佳;各时期适宜土壤相对含水量水分处理组合以60%-80%-70%或60%-80%-60%优于其它组合。

Study on Temporal and Spatial Dynamics of Soil Moisture in Flue-cured Tobacco under Control of Lysimeter

The temporal and spatial dynamics of soil moisture of flue-cured tobacco were studied by lysimeter experiment. The results indicated that in the growing period of tobacco plant, changes of soil water contents within 0 to 20 cm depth layers was the most significant, but followed by layers within 20 to 40cm depth and it was the most stable within 40 to 60cm depth. In addition, mathematical models describing the changes of soil water contents with time within 0 to 20 cm, 20 to 40 cm, 40 to 60 cm depth were also proposed, with which the temporal dynamics of soil water in flue-cured tobacco could be predicted. Also, it was good that irrigation calculating wetness depth was 20 to 30 cm at the root extending stage, 50 to 60 cm at the vigorous growing stage and 30 to 40 cm at the maturing stage; and the optimum relative soil water combining was better than others when it was at 60%-80%-70% or 60%-80%-60%.