Transport laws of soil water and heat in the maize field irrigated from the film hole

It is of importantly instructive meanings to study transport laws of soil water and heat for practical application of film hole irrigation technique. Dynamic variations of soil water content and temperature were analyzed in maize growing period through the field contrast trial of film hole irrigation and common bare soil surface irrigation method. The results showed that the transport laws of soil water and heat were identical on the whole, and with the increase of soil depth, soil water content increased, soil temperature decreased, the temperature difference between soil adjacent layers reduced, temperature peak value lagged, temperature diurnal amplitude diminished. The relationship between diurnal amplitude of soil temperature and soil depth could be fitted by the exponential function. Compared with two disposals, the film hole irrigation method favored to preserve soil moisture and to adjust soil temperature, the soil water content and temperature were higher markedly, and temperature amplitude collectively was less in the field irrigated from film hole than those in check plot. The differences of soil temperature and water content became small gradually between the two disposals along with the increase of soil depth. It was also approved in the trail that maize productive characteristics, yield and water use efficiency of irrigation water were more excellent in the field irrigated from film hole than the check plot. It is obviously proved that film hole irrigation benefits maize need on soil water and heat, which can accelerate growth and increase yield.