栽培番茄的塿土和黄绵土水分和温度变化规律

用土柱试验,研究了栽培樱桃番茄(Lycopersicon esculentum var.cerasiforme Alef.)的塿土和黄绵土水分运移和温度变化规律,水分运移模型选用土壤中水分分布的动力学模型,土壤温度、空气温湿度变化选用正弦曲线模型。结果表明:塿土在各个不同深度的平均含水量均高于黄绵土,塿土的入渗速率高于黄绵土,同一深度塿土温度高于黄绵土,土壤温度随着深度的增加具有明显的滞后性;黄绵土中樱桃番茄的水分利用效率大于塿土,空气温湿度、土壤温度和土壤含水量相互影响。水分运移模型在土壤浅层处可以得到很好的拟合效果,在拟合方程的变量范围内,根据时间可以较准确的确定樱桃番茄盛果期土壤浅层含水量,对于进一步提高农业干旱防御能力、有效制定节水灌溉计划、提高水分利用效率提供了理论依据。

The periodicities of water content and temperature variation for tomatoes in the cumulic cinnamon soils and the loessial soils

In this paper we report the findings from experiments using soil columns to investigate changes in water content and temperature in cumulic cinnamon soils and loessial soils which were used to grow cherry tomatoes (Lycopersicon esculentum var. cerasiforme Alef.). A mathematical model for soil water distributions was used to simulate the vertical changes in soils water, and a sinusoid model was selected to analyse soil and air temperature as well as the changes in air humidity. The results show that the average soil water content and the infiltration rate in the cumulic cinnamon soils are higher than those in the loessial soils. The temperature in the cumulic cinnamon soils is higher than that in the loessial soils at the same depth. The soil temperature has obvious hysteresis as the depth increases. The water use efficiency of tomatoes in the loessial soils is higher than in the cumulic cinnamon soils. The air temperature, relative humidity, soil temperature and soil water content influence one another. The mathematical model in this study effectively simulates the water movement in the soil above 20 cm. Within the variable range of the variables in the mathematical equation, the water content in the small depths can be accurately determined using the elapsed time in the cherry tomatoes at the full fruit period, which provides a theoretical basis for improving the drought resistance, scheduling water-saving irrigation plans and improving water use efficiency.