Mechanism And Application Research Of The Emitters Clogging Control Method By Micro-nano Bubbles Of Drip Irrigation Systems With Biogas Slurry

Objective:Biogas slurry is rich in nutrients and is a natural organic fertilizer,which is often used in farmland irrigation.Drip irrigation is considered as the most reliable way to irrigate marginal water such as biogas slurry,which can prevent the deep leakage of pollutants and improve the utilization efficiency of water and fertilizer.However,the composition of biogas slurry is complex,which contains a lot of microorganisms,salt ions and solid suspended solids,which can easily cause emitter clogging and affect the normal work of drip irrigation system.Traditional chlorination treatment can control the clogging of emitter,but this method increases the input of users,ignores the needs of users for crop yield increase,and has a certain negative impact on the environment.Therefore,it is urgent to find a clean and efficient method for controlling the clogging of emitter in biogas slurry drip irrigation system.Some studies have shown that micro-nano bubble water can inhibit biofilm pollution,it also can improve the yield and quality of crops,so micro-nano bubble is expected to become a method to control the emitters clogging under biogas slurry drip irrigation systems,improving crop yield and water saving method.However,at present,there are no reports on the research of controlling the blockage of emitter with micro-nano bubble water and the application of drip irrigation with biogas slurry-micro-nano bubble water in agricultural production.Methods:Based on this,two experiments were carried out.Experiment 1 studies the blocking mechanism of oxygen micro-nano bubble water?O₂-MNBW?controlling the emitter clogging of biogas slurry drip irrigation system.Three concentrations of O₂-MNBW(O_1:0,O_1:1 and O_1:1)were set,and 3 types of emitter?E₁,E₂ and E₃?were set.At the same time,experiment 2 was carried out to study the effects of micro-nano bubble water from different air sources on the growth and yield of crops.Six concentrations of O₂-MNBW(O_1:0,O_1:1,O_1:2,O_1:4,O_1:8,O_1:16),N_1:0,N _1:4,and N _1:16 concentrations of nitrogen micro-nano bubble water?N₂-MNBW?,He_1:0,He_1:4,He _1:16 helium micro-nano bubble water?He-MNBW?of 3 concentrations was used to study the effects of micro-nano bubble water on watermelon yield and water use efficiency?WUE?in facilities.Through these experiments to explore the mechanism emitters clogging control method by micro-nano bubbles of drip irrigation systems with biogas slurry,study the influence of different air sources on the watermelon in facilities,and establish the technology and application model of the emitters clogging control method by micro-nano bubbles of drip irrigation systems,improving of crop yield and WUE.Results:?1?O₂-MNBW can control the jam of the emitter in the biogas slurry drip irrigation system.Compared with CK(O_0:1),the dry weight and EPS quality of plug in the irrigator under O_1:0 treatment decreased by 31.0%⁴9.0%,29.0%⁵3.0%respectively,and Dra and CU increased by 15.0%⁴5.0%,24.0%⁴7.0%.Compared to the O_1:1 treatment,the O_1:0 treatment was the most effective in controlling the blockage,Dra and CU improving by 30.0%,23.0%?2?Compared with CK,MNBW treatment with different air sources increased the yield of watermelons in facilities by 3.73%³3.88%,but the improvement effect was affected by the air source type and concentration.The effect of increasing production and saving water of O₂-MNBW at different concentrations was better than that of N₂-MNBW and He-MNBW.Compared with CK,the yield of watermelon under O₂-MNBW treatment increased by7.81%³3.88%,and WUE increased by 7.81%³3.90%.?3?Compared with CK,the yield and WUE of watermelons in facilities were all increased with different concentrations of O₂-MNBW treatment,and showed an increasing trend with the increase of concentration.The yield of o1:0 treatment was the best.Compared with other concentrations of O₂-MNBW treatment,the yield was increased by 0.51%²2.90%,and the yield of WUE was increased by 0.52%²2.89%,respectively.Conclusion:considering the influence of factors such as emitter clogging,crop yield and WUE,the concentration of 1:0 O₂-MNBW is recommended as the optimal mode for controlling emitter clogging and agricultural production application in biogas slurry drip irrigation system.