地下滴灌系统灌水器堵塞特征识别及微胶囊化材料靶向控堵方法

Subsurface drip irrigation (SDI) technology is regarded as one of the most effective water-saving technologies along with the highest yields, this is mainly because it directly supplies the water and fertilizer to the crop root zone without unnecessary evaporation and leakage. However, the complicated micro-biological environmental characteristics in the crop root zone makes the emitters more likely to clog. The emitter clogging issue has become the key barrier to the large-scale promotion of SDI technology. This project focuses on solving the SDI emitter clogging issue and improving the operating benefit, and studies the emitter clogging characteristics of SDI system and quantifies their difference to the surface drip irrigation system. Figuring out the individually contributions of difference types of clogging (including physical, chemical, biological, negative pressure suction and root invasion) to the whole clogging process, as well as their coupled interactions with each other. Thus acquires the most critical type of clogging among them. Meanwhile, studying the dynamic variations of the key components of clogging substances inside emitters and their responses to the multiple influential factors. And then establishing a kinetic model for the clogging substances inside SDI emitters, under the circumstances of multiple clogging types and different influential factors. Then the microencapsulation materials, which is released slowly and effectively and targetly, is introduced to control SDI emitter clogging. Taking the crop invasion effect as example, which is easily to be triggered and then quickly increases clogging degree, the appropriate mode in controlling crop invasion is established using microencapsulation method. The results acquired in this project will strongly support the long-term and high-performance operation of SDI systems, and enhancing their large-scale promotions.

地下滴灌技术因其根区水肥定向供给、地表蒸发和深层渗漏低等特性被认为是最节水增产的高效节水灌溉方式之一，但复杂的作物根区微生境使得灌水器堵塞问题更突出，已成为制约地下滴灌技术规模化推广的关键阻碍。本项目以解决地下滴灌系统堵塞问题、提高系统运行效益为根本目的，系统研究了地下滴灌系统灌水器堵塞发生规律，量化了地下滴灌系统灌水器堵塞发生特征与地表滴灌系统的差异性，全面辨识物理、化学、生物、负压吸泥和根系入侵等五种类型堵塞对整体的贡献程度及耦合作用途径，筛选出其中最关键的诱因。同时研究灌水器内部特征组分动态变化特征及其对多因素的动态响应特征，建立多因素影响、多堵塞类型共存条件下的地下滴灌灌水器堵塞物质生长动力学模型。引入“有效缓释、靶向灭杀”特性的微胶囊化材料，以容易“触发”而导致灌水器堵塞迅速加深的根系入侵为探索对象，建立适宜地下滴灌系统灌水器的微胶囊化材料控堵方法。旨在为地下滴灌系统长期、高效运行及其规模化推广提供理论支撑。

地下滴灌被认为是最具节水增产潜力、规模化推广优势的高效节水灌溉技术，但地埋系统所处复杂的根区微环境导致灌水器堵塞问题严重，成为制约其应用推广的关键阻碍。本项目借助连续多年运行的糖料蔗地下滴灌系统研究了地下滴灌系统灌水器堵塞规律及年际变化特征，探究并定量表征了灌水器内部堵塞物质形成和生长过程，且发现堵塞严重的灌水器内部均发生根系入侵；并以此为研究重点，引入“有效缓释、靶向灭杀”特性的微胶囊材料改性方法，确定了氟乐灵微胶囊改良灌水器产品流程方法及氟乐灵缓释过程曲线，进而结合室内盆栽试验及温室种植试验系统探究了该技术对缓解灌水器堵塞、控制根系入侵、作物产量和品质、土壤酶活性和微生物群落等方法影响，初步确定了适宜的氟乐灵微胶囊有效施用浓度。研究成果已发表SCI论文2篇、2篇SCI论文审稿中（4篇均为JCR Q1），EI论文1篇；已授权PCT国际专利、国家发明专利各1项，公开国家发明专利1项。研究成果可为地下滴灌系统长期高效运行及防止堵塞发生的新方法提供理论支撑。