基于Penman模型的蔬菜大棚土壤水分平衡研究

Research on Soil Moisture Balance of Vegetable Greenhouse Based on Penman Model

为达到土壤水分平衡状态,获得蔬菜大棚中作物生长的最佳土壤墒情,则需要建立起有效的模型.本研究以Penman模型为基础,对参数进行简化,提出了改进的温室大棚土壤水分平衡模型,降低了计算复杂度,提高了模型的计算效率.通过采集温室蔬菜大棚的实时气象数据,包括土壤温湿度、大气温湿度、通风风速、土壤热通量,使得数据更加准确,提高了计算的精度.实验采集蔬菜大棚作物处于发育期内的数据进行验证,模型计算获得的数据与实测值相比误差非常小.结果表明,该模型完全可以作为蔬菜大棚滴灌控制的一种可靠依据,具有较高的实际应用价值.

It is necessary to establish an effective model to achieve soil moisture balance so as to get the op-timal soil moisture for crops which grow in vegetable greenhouse. Therefore, we simplify the parameters based on Penman model and then propose our improved soil moisture balance model in greenhouse, which reduces the computational complexity, as well as improves the efficiency of calculation. The accuracy of da-ta and computation is greatly improved because we collect the meteorological data in real time, including soil temperature and humidity, greenhouse temperature and humidity, ventilation velocity, and soil heat flux. The experiments are carried out by the use of the data of crops from vegetable greenhouse in their de-velopmental phase. The comparison data between the measured values and calculated data from our model are collected. The experimental results show that deviation ratio is very small. Thus, our model is reliable with high practical value for drip irrigation system in vegetable greenhouses.