I. Efficient use of rainwater resources Due to the constraints of conditions, the vast majority of people in the past have remained at a spontaneous stage in their use of rainwater, and rainwater resources have neither formed a scale nor produced economies of scale. On the one hand, it causes the waste of water resources. On the other hand, it has long been plagued by water shortages. With the increasing scarcity of water resources, water conflicts have intensified, and as a potential water resource available in arid and semi-arid regions, rainwater has attracted the interest of experts and scholars on water issues. It has conducted in-depth research and has obtained a number of meaningful achievements. The government attaches great importance to and supports the continuous development and utilization of its depth and breadth, making rainwater resources and sustainable development and utilization widely realized. 1. Construction of terraced fields, storage of rainwater, and development of rain-fed agriculture. Drought and semi-arid regions have complicated terrain, many ravines, thin soil layers, poor water retention and fertility retention, and runoff from rainfall quickly drains, scours the soil, and is prone to drought after rain. The output of crops is low and unstable. Therefore, engineering measures must be taken to build high-standard terraces. In order to better intercept rainwater, gully planting techniques are generally used. In this way, the effective soil water reserves can be increased, the ability to withstand droughts can be increased, and agricultural arable land measures, such as drought-resistant seed, organic fertilizer, and soil film cover, can not only increase agricultural output, but also prevent soil erosion and reduce mud. Sand hazards to rivers. 2.Using courtyards, yards, and roof surfaces to collect rain, develop garden economy, farmer's houses, front and rear sides of villages, and generally have laminated courtyards and yards. Most of the roofs are cement-lime soil and roof tiles. Rainwater created the conditions. According to local rainfall, rainfall intensity, and the size of the rainwater catchment area, water storage facilities (water cellars and water kilns) are built in the courtyard, on the side of the yard, or on the land, and rainwater is stored and stored during the flood season. In addition to solving people’s drinking water, You can also use the limited water resources to develop the courtyard economy. Such as planting, aquaculture and small-scale processing industry. Practice has proved that this is an effective way for mountainous people to get rid of poverty and become rich and affluent. At the same time, it has also improved the sanitation conditions in rural areas in the mountains, reduced disease, and improved health. 3. Utilizing sloping land and roads to collect rain and developing irrigation fields for field crops There are many sloping lands in the general area. There are tarmac roads or gravel roads in the countryside, and there are many soily field roads. These slopes and roads can be directly collected or modified. Collect rainwater. The general soil roads should be smoothed and rolled, and the lateral slope to the roadside drainage should be set. Some waste slopes should be compacted to the original soil, and the dry bulk density after compaction should not be less than 1.5t/m3. If the natural rainwater collection surface is insufficient, an artificial impervious impoundment project (water cellar or water kiln) can be built. The water cellar (dry well) is generally filled with water from 30 to 50 m3, and the water storage of the water kiln is generally 100-200 m3. The irrigation system can be used for irrigation of field crops (grain, melons, etc.), and the irrigation of critical water or life-saving water is generally adopted because of the limited amount of water. 4. Combine the comprehensive management of small watersheds, develop irrigation systems for agriculture and forestry in the hilly areas, and combine small watershed management with the organic integration of water and soil conservation and rainwater harvesting. Through integrated measures such as gathering, interception, introduction, storage, and irrigation, The use of rainwater resources within the basin to develop irrigation of field crops or woodlands not only protects the soil but also promotes the development of agroforestry in the mountainous areas. II. Appropriate water-saving irrigation technologies for rainwater use Due to the constraints of terrain, rainfall resources and economic conditions, it is not possible to use traditional surface irrigation methods and certain water-saving irrigation methods, and it is impossible to fully irrigate and only implement irrigation keys. Local irrigation of water or life-saving water maximizes the benefits of irrigation water. Now introduce several kinds: 1. Micro-irrigation technology Micro-irrigation (including drip irrigation, micro-sprinkler irrigation, Yongquan irrigation) as a result of water saving, high yield, high quality, adaptability, can make full use of small water sources and other characteristics, the most suitable for the use of rainwater . Since there is more than one cellar (kiln) as an irrigation system, the control area is small, and the layout and calculation of the design are relatively simple. Except for the planning and design of large-scale cellar groups, the calculation does not usually need to be complicated. (1) Choose the appropriate micro-irrigation form. According to the pit (kiln) area terrain, soil quality, crops, etc., select the appropriate irrigation method. For vegetable gardens (including plastic greenhouses and solar greenhouses), drip irrigation is suitable. For orchards, drip irrigation, micro-spray irrigation, and Yongquan irrigation are suitable. Wherever there is a large amount of evaporation, micro sprinkler irrigation should not be used. For garden-planted flowers, edible fungi, etc., microspray irrigation can be considered. For food, cotton, melon crops, drip irrigation is suitable. (2) Select the type of micro-irrigation. To save investment, where conditions permit, first consider the self-pressing method. When there is no self-pressure condition, consider using an artificial hand pump or a micro-pump to pump water according to the economic and power conditions. According to the control area, the type of crop is fixed or mobile type. Orchards, flowers, edible fungi, melons, etc., due to wide spacing or irrigation frequency, and high economic efficiency, generally adopt fixed type. For large grain crops, cotton and other dense crops or some small-scale courtyard farming, mobile is used. There are currently two mobile modes, namely a micro-irrigation system, two cellars, control of about 0.27m2 (4 acres) of land, the first hand-driven pump for power, or a set of micro-irrigation systems, four cellars, control of about 0.53 Hm2 (8 acres), the first mini-electric pump for power. When moving, a capillary tube can be moved several times laterally, and one set of capillary tubes can be moved to another place. For the electric pump system, in order to keep the pump, a set of capillary tubes can be used. When a group is filled, the standby group of irrigation water is opened first, and then a set of capillary water that has been stopped for irrigation is released and then moved to another place. Where the irrigation is to be carried out, such movement is repeated until the area controlled by a pit (kiln) is filled, and then the entire micro-irrigation system is moved to another cellar (kiln) for further irrigation. 2. Anti-drought and siting water technologies In northern arid and semi-arid regions, due to low rainfall and poor soil moisture during the sowing of crops, they often cause late emergence or lack of seedlings, or even failure to emerge, seriously affecting agricultural production. In order to ensure full seedlings and strong seedlings, a method known as sitting water is used. The operating procedures are planing (or trenching), water injection, spot seeding, fertilization, covering and repression. This method can be timely sowing, improve the quality of sowing, to achieve the purpose of Miao Qi Miao Zhuang, the emergence rate of more than 95%, and can improve drought resistance, improve fertilizer efficiency and promote early yield increase. According to the Ningxia test, corn can increase production by about 16%. 3. Plastic film collecting hole irrigation technology This technology is carried out on the basis of anti-drought and sitting water seeds. Its operation procedure is cover film; releasing air; putting seedlings out of the film; expanding the seeding pit into a pot-shaped concentrator with a diameter of 30 cm. Cave; closed the seeding pit with sand; collect the water on the mulching film at other locations through the low-gravity catching effect of the pot-shaped collector hole to achieve the purpose of collecting the flow of the hole. 4. Injecting irrigation technology A method of using a special sprinkler to directly inject water (or water and fertilizer solution) into the root zone soil. At present, Ningxia is borrowing a LYJ top-loading gun and installing it on agricultural sprayers. It will inject water into the root zone of the crop through nozzles depending on the air pressure of the sprayer. Its characteristics are as follows: First, irrigation, topdressing, and root zone application can be completed in one operation; secondly, it is suitable for critical water irrigation of fruit trees, melons, corn, and other rare crops in arid regions; and third, quantitative irrigation can be performed according to the growing conditions of the crops. Less irrigation, shallow irrigation, vigorous irrigation, deep irrigation. Irrigation quota is only 2-3m3/0.067hm2, and each plant (site) is injected with 0.5-1.Okg water. 5. Canister Percolation Technology The emitters for percolation of earthen jars are made by firing unglazed rough clay with micropores (also with 1mm holes drilled at a certain distance from the tank wall). Manual irrigation is required during irrigation. The tank is filled with water, and the water seeps through the micropores around the tank. With the help of the soil capillary, the water seeps into the root zone of the crop. Tiles buried deep 30-40cm, the bottom is not punched, the tank wall thickness 4-6cm, the upper mouth capped, cover the center to leave a 1Omm round hole, for the exhaust and water injection into the tank. The seepage radius can vary from 30 to 40cm depending on the soil. The manufacturing process of the crock is simple, and it can be obtained locally, and the construction cost is cheap. Suitable for crops with wide row spacing, if trees, melons and corn are used for drought protection seedlings or key water use, the earthen jars shall be buried immediately after sowing. The fruit trees shall be buried at 2/3 of the crown radius.