Effects Of Different Factors On Film Hole Irrigation With Brackish Water Nitrogen And Salt Transport

Based on summarizing and analyzing the domestic and film hole irrigation and micro irrigation with brackish water theory and technology research, technical route by indoor experiments and theoretical analysis of the combination, mainly studied the effects of soil, film hole diameter, brackish water solution and other factors on film hole irrigation, nitrogen, soil water salt transport characteristics. The main research results are as follows:1, to study soil factors free into the effects of water and nitrogen salt migration and distribution after the infiltration of film hole irrigation of brackish water. The soil factors include: the two factors of initial soil water content and soil bulk density.The initial soil moisture increased, at the same time the cumulative infiltration and wetting front transport distance larger; after infiltration, different initial water content of soil moisture and nitrate nitrogen content were increased with the distance from the film hole decreases gradually, in the same infiltration time, initial soil water content the greater the same location, soil moisture increased, the nitrogen content in the same position of soil nitrate decreased first and then increased; soil salt content of different initial moisture content decreased with the increase of the distance from the membrane pores and increase gradually, in the same infiltration time, along with the increase of initial soil water content, the same position the soil salt content decreases first and then increases.Soil bulk density is bigger, at the same time the cumulative infiltration and wetting front transport distance is small; after infiltration of different soil bulk density, soil moisture and nitrate nitrogen content decreased with the increase of distance from the membrane pores decreases at the same time, infiltration, soil bulk density is bigger, the same position the soil moisture and nitrate nitrogen content is smaller; different soil bulk density of the soil salt content decreased with the increase of the distance from the membrane pores gradually increased at the same time, infiltration, soil bulk density is bigger, the same position as the soil salt content is small.2, research on film hole diameter of film hole irrigation of brackish water free into the effects of water and nitrogen salt migration and distribution after the infiltration. Film hole diameter is large, at the same time the cumulative infiltration and wetting front transport distance larger; after infiltration of film hole diameter, different soil moisture and nitrate nitrogen content decreased with the increase of film hole distance decreases gradually, at the same time under film hole infiltration, the greater the diameter the same position, soil moisture and nitrate nitrogen content increased; soil salt content of different film hole diameter decreased with the increase of film hole in the distance gradually increased, at the same time under film hole infiltration, the greater the diameter, the same position of the soil salt content is small.3, studies the factors of brackish water solution free into the effects of water and nitrogen salt migration and distribution after the infiltration of film hole irrigation of brackish water. The brackish water solution factors include: sodium adsorption ratio, fertilizer solution concentration and the micro salty water salinity of three factors.Sodium adsorption ratio is larger, at the same time the cumulative infiltration and wetting front transport distance is small; after infiltration, different sodium adsorption ratio of soil moisture and nitrate nitrogen content decreased with the increase of distance from the membrane pores decreases at the same time, the infiltration, the greater the sodium adsorption ratio and the same position on the soil moisture and nitrate nitrogen content decreased first and then increased; different sodium adsorption ratio of the soil salt content decreased with the increase of the distance from the membrane pores and increase gradually, in the same infiltration time, sodium adsorption ratio is larger, the same position as the soil salt content decreases first and then increases.Fertilizer concentration is larger, at the same time the cumulative infiltration and wetting front transport distance is greater; after infiltration of fertilizer solution concentration, different soil moisture and nitrate nitrogen content were decreased with increasing distance from the film hole infiltration, at the same time, along with the increase of the fertilizer concentration large, the same position as the soil moisture content decreases first and then increases and then decreases, the nitrogen content in the same position on the soil nitrate increased; different fertilizer solution concentration of soil salt content decreased with the increase of the distance from the membrane pores and increase gradually, in the same infiltration time, along with the fertilizer solution concentration increased. At the same position of the soil salt content first decreased then increased small big.Brackish water salinity is greater, at the same time the cumulative infiltration and wetting front transport distance is greater; after infiltration, different micro salty water salinity of the soil moisture and nitrate nitrogen content were increased with the distance from the film hole irrigation decreases gradually, at the same time, the micro salty water salinity more, the same position on the soil moisture and nitrate nitrogen content of more big, different micro salty water salinity of the soil salt content decreased with the increase of the distance from the membrane pores and increase gradually, at the same time with the increase of infiltration, brackish water salinity, the same position as the soil salt content first the reduction of large increment after small increases again.The above research results for the development and utilization of brackish water through the film hole irrigation irrigation manner to provide a theoretical basis for the further development of irrigation on farmland, farmland irrigation, water-saving and efficient fertilization lay a scientific foundation.