Exploring new water-saving models for agricultural irrigation

Exploring new models for agricultural water-saving irrigation can contribute to the research and reform of agricultural water conservancy irrigation and water-saving measures. It can also contribute to the improvement and perfection of the agricultural water-saving technology system and water-saving management technology system, the integrated development and utilization of water resources, and the improvement of irrigation water use efficiency, increased agricultural production and value, and increased income for farmers. This article combines the practice of agricultural production management to analyze and study agricultural water conservancy irrigation models. It also proposes a new model for agricultural irrigation water saving to promote sustainable agricultural development, addressing the problems of water saving in agricultural water conservancy irrigation.

With increasingly scarce and precious water resources, the scientific use of water, rational irrigation, and better adoption of new water-saving technologies and equipment are important issues in agricultural water conservancy irrigation. A sound and complete water-saving agricultural technology system can fully utilize agricultural water resources and comprehensively improve the utilization rate and efficiency of irrigation water. Therefore, the water-saving agricultural technology system and water-saving management technology system are technical measures that can achieve high-yield and high-efficiency crops. The scientific and rational application of a comprehensive technical system composed of various water-saving technologies from aspects such as water resources, engineering, agriculture, and management can not only rapidly improve the overall utilization rate of agricultural water resources but also significantly increase crop yields per unit area and total area, improve comprehensive benefits, and comprehensively promote the sustainable and stable development of the agricultural economy.

1 Agricultural water-saving technology system and management system

Water resources rational development and utilization technology system. The rational development and utilization of agricultural water resources requires various engineering measures, such as technologies for the rational development and utilization of surface water and groundwater, well testing and transformation technologies, and multi-water source integrated utilization technologies. Irrigation engineering water-saving technology system. Irrigation engineering water-saving technology is the key content of the water-saving agricultural technology system, with very significant effects. It mainly includes low-pressure pipeline irrigation technology, sprinkler irrigation technology, micro-irrigation technology, channel anti-seepage technology, membrane irrigation technology, and improved ditch irrigation technology. The agricultural water-saving technology system mainly includes water-retention and soil-moisture conservation tillage technology, cultivation techniques to improve crop drought resistance with appropriate rainfall, straw or film mulching soil-moisture conservation technology, chemical agent drought resistance and soil-moisture conservation and water-retaining agent application technology, quota irrigation, and water-saving and drought-resistant crop breeding technology. The water-saving management technology system is to establish and improve various water management organizations, formulate engineering management and operation management systems, and achieve planned water use, optimized water distribution, and reasonable water fee collection.

1.1 Water-saving characteristics of channel anti-seepage technology

Canals are the main water conveyance method for farmland irrigation in China, and canal anti-seepage is a major technical measure for the development of water-saving irrigation in China. According to the anti-seepage materials, it can be divided into soil compaction, three-mix soil surface protection, brick lining, concrete lining, plastic film anti-seepage, and asphalt surface anti-seepage. Channel anti-seepage technology can reduce water seepage loss during the canal water conveyance process, improve the water utilization coefficient of the canal system, improve the safety guarantee rate of canal water conveyance, improve the anti-scouring capacity of the canal, and increase the water conveyance capacity.

1.2 Classification and characteristics of sprinkler irrigation technology

Sprinkler irrigation, also known as spray irrigation, uses specialized equipment such as power machinery, water pumps, and pipelines, and the natural drop of water to deliver water to the irrigation area. It sprays water into the air through sprinklers, scattering it into fine droplets for uniform distribution and irrigation. The sprinkler irrigation system includes water source projects, power machinery, water pumps, various pipelines, sprinklers, and control equipment. Sprinkler irrigation systems are divided into fixed, semi-fixed, and mobile types. In a fixed sprinkler irrigation system, all components are fixed, or all components except the sprinkler are fixed. In a semi-fixed sprinkler irrigation system, the sprinkler and the branch pipe with the sprinkler can move on the ground, while the other parts are fixed, and the pipe section is connected to the water valve. In a mobile sprinkler irrigation system, except for the pond, well, and channel water sources, the power machinery, water pump, pipeline, and sprinkler are all mobile.

2 Six major problems existing in agricultural water conservancy irrigation

1. Insufficient promotion of new technologies and equipment for water-saving irrigation. High-efficiency water-saving irrigation technologies such as sprinkler and drip irrigation are only limited to cash crops and need to be comprehensively promoted on a large scale and large area.

2. There are great shortcomings in the irrigation area and water-saving irrigation project mechanisms. There are many problems such as unclear property rights, unclear management responsibilities, unclear separation of government, administration, and enterprises, lack of supervision and incentive mechanisms, extensive management, and inflexible scheduling.

3. Farmers lack awareness and enthusiasm for water-saving irrigation. Farmers in areas with abundant water resources lack motivation and enthusiasm for water-saving irrigation due to concerns about economic losses.

4. Shortage of funds for water-saving irrigation restricts development. Due to the shortage of funds, existing irrigation projects lack maintenance funds, are seriously aging, and have been neglected for many years. The irrigated area has been declining year by year, and irrigation efficiency has continued to decrease. The supporting funds for the construction of new water-saving irrigation projects have not been in place, resulting in the inability to achieve the corresponding development scale.

5. Water-saving irrigation lacks flexibility based on local conditions. In the process of promoting advanced water-saving technologies in some places, scientific planning cannot be formulated based on local conditions, there is no feasibility study, and the targeting is poor, so that water-saving projects cannot function normally.

6. The quality of water-saving irrigation equipment is poor. The quality of water-saving irrigation equipment varies, and the standardization and serialization of equipment are poor, and maintenance services are inadequate. Many engineering equipment has serious quality problems, and maintenance is not timely, resulting in a short service life of the project, a high failure rate, and to a certain extent, affecting the promotion of water-saving irrigation technology.

3 Four measures for agricultural development of water-saving irrigation

3.1 Formulate a complete water-saving system based on sustainable development

At present, agricultural water-saving methods cannot completely improve the water shortage situation. In order to ensure a good harvest in drought conditions and increase grain production, people are constantly drilling more and deeper wells, while using the water saved by water-saving irrigation to continuously expand the irrigated area. This is not strictly resource-type water saving. Therefore, we must stand at the height of sustainable development and consider agricultural water saving from a more macroscopic perspective. Agricultural water saving is both an engineering and technical problem and a social and economic problem. It involves agricultural planting structure adjustment, rural household contract responsibility system management methods, industrial structure adjustment, grain production benefits, and the vital interests of farmers. To solve these problems, multiple departments must closely cooperate and coordinate, comprehensively consider various factors restricting the development of agricultural water saving, and formulate a complete and practical water-saving agricultural technology system based on local conditions.

3.2 Fully implement rational planning to achieve efficient water-saving promotion

Surface water utilization in irrigated areas includes in-area water storage and external water diversion systems. Analysis can yield the available water resources process over many years. The groundwater aquifer in the irrigated area can be considered a regulating reservoir. Its replenishment includes rainfall replenishment, seepage replenishment from canals and drainage ditches, lateral replenishment from external groundwater, inter-layer replenishment from internal groundwater, and artificial recharge; its consumption includes evaporation, outflow, and exploitation. The two water sources can be jointly dispatched, and equilibrium analysis can be performed using the regional equilibrium method or the unsteady groundwater flow method; under certain exploitation layout conditions, to determine a reasonable exploitation intensity, or under a certain exploitation intensity, to determine the amount of surface water replenishment to groundwater and the corresponding replenishment area, or to determine the regional exploitation layout according to the replenishment method and exploitation intensity. In alluvial plains or the middle and lower reaches of rivers, where the groundwater level is high and the reliability of external water sources is low, well irrigation should naturally be developed to supplement canals with wells; if groundwater is severely over-exploited, water use should be reduced or upstream water diversion should be uniformly controlled, local water storage projects should be built, and river water sources should be used for water diversion, storage, or groundwater recharge. Even within an irrigated area, the dynamic laws of surface water and groundwater are different, or upstream combines wells and canals, with canals being the main source, and downstream combines wells and canals, with wells being the main source.

3.3 Increase Policy Support and Establish the Importance of Water Conservation

Currently, investment in agricultural water-saving projects mainly relies on collective funding, farmer fundraising, and national subsidies. The initial investment in projects is large, and national subsidies are scarce, with most funds needing to be raised by farmers themselves. However, the public is not yet wealthy enough to contribute more money to agricultural water-saving projects. Therefore, governments at all levels should include agricultural water conservation work on their important agendas, forming a system to continuously increase support in terms of policies and funds, ultimately establishing the importance of agricultural water conservation, and creating a social atmosphere of caring for, cherishing, and protecting water.

3.4 Improve the Efficiency of Medium- and Low-Yield Fields and Expand the Area of Water-Saving Irrigation

Appropriate water-saving irrigation technologies should be selected, and development plans should be formulated based on local conditions. Avoid impulsive decisions and blindly introducing unsuitable "Sample Projects" for local promotion. The transformation of medium- and low-yield fields is a key focus of future agriculture. We need to improve the efficiency of medium- and low-yield fields and expand the area of water-saving irrigation. For saline-alkali land, we should improve water flushing of salt, water suppression of alkali, and soil improvement, and research and formulate suitable flushing quotas and water-saving technical measures.