亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

In view of the obvious differences in root depth, irrigation time and irrigation amount between crops and fruit trees in agroforestry, it is difficult to take into account the irrigation problems of deep roots of fruit trees and shallow roots of interplanting crops by traditional single irrigation method. In order to achieve efficient irrigation of deep and shallow roots, a complementary device of micro-sprinkler irrigation and ceramic infiltration irrigation based on water pressure control was developed. On the basis of the overall structure design of the device, the optimal configuration of the three core components: ceramic subsurface irrigation pressure converter, micro-sprinkler pressure converter and telescopic device was focused. The hardness (70HA) and thickness (1.5mm) of the elastic diaphragm in the ceramic subsurface irrigation pressure converter were optimized through the full test of two factors and six levels. Under this condition, the working pressure range of underground irrigation can be 0.015~0.055MPa, and the flow rate was 10L/h. Based on the structure design of the micro sprinkler pressure converter, the spring stiffness coefficient was 1500N/m, which can ensure that the micro nozzle did not spray water under low pressure (less than 0.066MPa). The critical elongation pressure of the telescopic device was 0.066MPa, which was consistent with the test results: when the water pressure reached 0.066MPa, the telescopic pipe began to extend. When it was 0.15MPa, the telescopic pipe rose to the highest point, and the micro nozzle started to work stably. On the basis of the above, the physical model of the micro-sprinkler irrigation and ceramic infiltration irrigation complementary device was made, and the performance test was carried out according to the national standards, and the model was applied in the greenhouse, the results showed that the device with 0.066MPa water pressure as the boundary, the deep roots of fruit trees were irrigated by low-pressure ceramic infiltration irrigation, and shallow roots were irrigated by high-pressure micro sprinkler irrigation. The complementary irrigation function was good, and the measured soil moisture content met the design expectations. The research result can provide an effective solution for efficient irrigation of deep and shallow roots in agroforestry.