Study On The Water And Nutrient Distribution Pattern In Soil Under Drip Fertigation

Drip fertigation technology has been accepted by many scientists for its merits of economy water and fertilization and can be controlled easily. It has been widely applied by some places overseas countries and our country. But the study of water and fertilizer distribution pattern in soil under the condition of drip fertigation is very restricted. The experiment was conducted to investigate the influence of dripping end flow and fertigation volume on the distribution pattern of water and fertilizer in soil, and to analyze the change rules of water NH₄⁺ -N,NO₃^- -N,available phosphate and available potassium in different deep soil layers under the condition of field. And draw thereinafter main conclusions.1,As the radius distances and soil layer depth increased, water content of soil will be lessened, and the rate of level reducer decreased as the soil depth increased. When dripping end flow increased, surface pond radius around drop increased, the moving distance in level of water increased, but the in leakage depth of water in vertical decreased; As irrigation volume increased, moving distances in horizontal and in leakage depths in vertical of water increased, and the change distance in horizontal is more obvious.2,NH₄⁺ -N moving belongs to"convection- adsorption control in step"style, Dripping end flow influenced NH₄⁺ -N moving and distribution obviously in soil. As dripping end flow increased, NH₄⁺ -N moving distance increased in level in soil , NH₄⁺ -N average density increased in level of 15cm and 0～2.5 cm in vertical. As fertigation volume increased, NH₄⁺ -N moving distance in soil increased not only in level but also in vertical, NH₄⁺ -N average density increased in the scope of 25cm in level and 0～25cm in vertical.3,NO₃^- -N moving belongs to"convection control"style. As the level distance increased, NO₃^- -N density decreased, as the soil layer depth increased, NO₃^- -N density increased firstly, and then reduced later, cumulate NO₃^- -N emerged round soil wetness peak in vertical. Dripping end flow increased, NO₃^- -N moving distance in horizontal in soil increased, NO₃^- -N density increased in level of 25 cm and 0～25 cm in vertical in soil. fertigation volume increased, NO₃^- -N average density increased in the scope of 15cm in level and 0～15cm in vertical. NO₃^- -N density decreased in the scope of 30 cm in level and 20～30 cm in vertical.4,Under the condition of drip fertigation, available phosphate and available kalium distribution in soil belong to"convection ruling, convection- adsorption control in step"style, as the soil layer depth increased, available phosphate and available kalium density decreased,...