Soil Temperature and Physical Properties of Soil, Depend on the Different Methods of Irrigation at the Field

Studies were made on the relation between the physical properties of soil and soil temperature in different methods of irrigation at the field.The results are summarized as follows:1) Increasing the amount of irrigation water, as indicated in Fig. 1, causes the increase of water content, and on the contrary, the decrease of air content. On the other side, soil content keeps rising up to the saturation, then gradually falls down to a certain value. In this way it was determined that the difference of soil properties above mentioned consequently controlled respectively specific heat, thermal capacity, and thermal conductivity.2) It should be emphasized as represented in Table 1 that the more soil content and percolation increase, the more thermal diffusivity and conductivity enlarge.3) In regard with temperatures of surface and interior of soil, it was observed, as shown in Fig. 2, Fig. 3 and Table 3, that variation of soil temperature on the surface was very intimately with thermal capacity, and that the variation in the interior was influenced by thermal diffusivity.