From August 16 to 18, 2024, the 7th Grass Industry Conference and the 10th Alfalfa Development Conference were held in Jinchang, Gansu Province. Guided by the China Animal Agriculture Association and the National Grass Industry Science and Technology Innovation Alliance, the conference was co-hosted by the Grass Industry Branch of the China Animal Agriculture Association, Gansu Agricultural University, Lanzhou University, and the Bureau of Agriculture and Rural Affairs of Jinchang City, with the assistance of the Gansu Grass Industry Association and the Yongchang County Grass Industry Association. With the theme of "Intelligent, Efficient, Green, and Water-saving", this grand event gathered industry elites and sparks of wisdom, witnessed the vigorous vitality of green development, and opened a new chapter of industry innovation and cooperation.

As an optimal location for alfalfa cultivation, Jinchang City not only boasts abundant light and heat resources and fertile soil conditions but has also successfully achieved efficient and sustainable development of the alfalfa industry through a series of green agricultural measures. The experience and achievements of Jinchang have provided valuable references and insights for other regions.

Shang Zhenqing, Technical Director of Hebei Runnong Water-saving Technology Co., Ltd., was invited to attend the conference and delivered a special report titled Application and Discussion on Subsurface Drip Irrigation Technology in Alfalfa Fields. From his unique technical perspective and based on years of practical experience, he elaborated in detail on the current application status of subsurface drip irrigation technology in alfalfa fields for the conference.

Subsurface drip irrigation technology involves laying drip tapes below the soil surface, allowing water and fertilizers to be delivered directly to the root zone of crops. This precise irrigation method promotes root absorption and enhances crop growth. Combined with a series of supporting measures—including weed control, water conservation to prevent seepage, water efficiency improvement to mitigate salinization, and soil fertility preservation—it effectively improves crop quality and increases yields. By precisely controlling soil moisture, the technology helps prevent crop diseases, while also improving soil structure, regulating the microclimate in farmland, balancing groundwater levels, reducing water waste, protecting the ecological environment, and ultimately promoting the sustainable development of agriculture.

In 2016, Runnong Water-saving launched a demonstration project for alfalfa subsurface drip irrigation (focused on water conservation and efficiency enhancement) in Liuba Township, Yongchang County. After years of practice, the company successfully built a 7,000-mu (approximately 466.7 hectares) alfalfa demonstration project in Yongchang County, accumulating rich experience in this field. It also plans to promote this technology nationwide. Subsurface drip irrigation not only contributes to improving crop yield and quality but also has the potential to drive the green transformation of agriculture, protect the ecological environment, and advance sustainable agricultural development.

The soil in Yongchang County is mostly sandy clay, characterized by small particles and poor water permeability. Based on these soil properties, Runnong Water-saving selected low-flow, shallow-buried drip tapes. Since the drip tapes are laid below the soil surface, they are protected from mechanical compaction, do not interfere with farming operations, and help maintain the flatness of the farmland.

Drip irrigation laterals have a long service life and are less prone to mechanical damage. Free from the harmful effects of ultraviolet radiation, they avoid mechanical damage caused by recovery, laying, and transportation. Since the launch of the alfalfa demonstration project in 2016, some drip tapes have not been replaced and are still in use, with an average service life of over 7 years.

Subsurface drip irrigation technology can improve water use efficiency and conserve water resources. According to local water usage habits and statistics from the local water management station, the annual water consumption for alfalfa irrigation via flood irrigation is at least 700 cubic meters per mu. Based on theoretical calculations and the actual application data of our company, the annual water consumption for alfalfa irrigation using shallow-buried drip irrigation is 450 cubic meters per mu, saving 250 cubic meters per mu compared with flood irrigation.

The subsurface drip irrigation tubes are buried 10-15 centimeters below the soil surface. This depth enables alfalfa to develop deeper root systems, making irrigation and fertilization more effective and reducing fertilizer usage by 30-40%. Additionally, the surface soil remains loose, which is more conducive to crop respiration and root development, thereby achieving the goals of improving crop quality and increasing yields.

The successful holding of this conference has promoted exchanges and cooperation within the industry, and more importantly, injected new impetus into the green, efficient and sustainable development of water-saving irrigation and the alfalfa industry. We look forward to working hand in hand with our colleagues in the industry to create a brilliant future together.