Method for water-saving cultivation of rice in saline-alkali soil

Abstract

The invention relates to a saline-alkali soil rice water-saving cultivation method, and belongs to the technical field of rice cultivation. Through soil improvement on the saline-alkali soil, effective planting of rice in the light and moderate saline-alkali soil, an underground irrigation mode and an overground irrigation mode, installation is easy and convenient, field operation is easy, irrigation can be conducted according to the root growth depth of the rice, and through accurate irrigation, the rice root zone is always kept in a light salt or salt-free environment. According to the natural rainfall condition, the rice is irrigated 8-10 times in the growth period, the irrigation amount is about 280-320 m < 3 > / 667 m < 2 >, water is saved by 50% or above compared with common flood irrigation, water and fertilizer integration can be achieved during topdressing, water and fertilizer are saved, the water and fertilizer efficiency is improved, and the utilization efficiency of water resources is improved and the rice yield is increased by controlling the irrigation time and depth. The device can be flexibly adjusted according to the water demand characteristics of rice in each growth period, and compared with traditional continuous irrigation, the rainfall utilization rate can be remarkably increased, the leakage amount can be reduced, and therefore waste of water resources is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of rice cultivation, in particular to a method for water-saving cultivation of rice in saline-alkali land. Background Art

[0002] There are large areas of saline-alkali land in northern my country, which are mainly used for cotton planting. However, the benefits of cotton have declined in recent years, and farmers need to "change cotton fields to rice". The traditional rice planting method is flooding cultivation, which consumes a lot of water. In the 1970s, a water-saving cultivation technology - rice film mulching cultivation technology - was introduced from Japan. In the 1990s, China's water resource problems became increasingly serious, and rice film mulching cultivation technology developed rapidly. At the end of the 20th century, film mulching cultivation technology formed a complete system for different low-yield, water-deficient, and high-cold rice fields in the south and north.

[0003] Chinese patent CN103798090A introduces a comprehensive rice planting method for saline-alkali land with film covering, which includes the following steps: applying base fertilizer to the field, transplanting rice seedlings to the field, and applying urea; irrigating the field 3-5 days before transplanting, and covering the rice with film before transplanting. The method is to first use large water to soak the field to wash the salt, and then cover the film and transplant the rice. Among them, large water soaking field washing salt requires a lot of water, which does not meet the needs of current water-saving cultivation. In addition, rice transplanting requires manual operation, which increases the labor intensity.

[0004] Chinese patent CN104969809A introduces a high-yield direct seeding technology for rice film covering. The basic method of this technology is to make a 165cm wide, 27cm wide and 17cm deep bed surface after washing salt with large water. When the bed surface does not sink, the film is covered manually. While covering the film, the film is inserted into the mud by hand for 3-5cm. After covering the film, a wooden planting device is used to punch holes, and sprouts are sown into the film holes manually, and covered with fine soil or humus soil. The difference between this technology and CN103798090A is that sowing sprouts and planting rice seedlings basically still requires large water washing salt; the amount of irrigation during the growing period will be greater, because the irrigation needs to submerge the bed surface. If only the bed ditch is irrigated, the bed surface will return salt. Summary of the invention

[0005] The present invention aims to solve the above technical problems and provides a method for water-saving cultivation of rice in saline-alkali land.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0007] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0008] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0009] S1. Soil improvement:

[0010] For medium to heavy saline-alkali land, soil improvement should be first carried out. Plants that absorb salt and alkali should be planted to reduce the salt content in the soil. After the plants grow up, they can be directly plowed as green manure. Unfermented organic fertilizer should be applied and turned into the soil to ferment. Microorganisms will produce organic acids during the reproduction process to convert salt, thereby reducing the salt and alkali content and obtaining converted land.

[0011] S2. Land preparation and fertilization:

[0012] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0013] S3, washing salt and making soil moisture:

[0014] Before direct seeding rice with film covering, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, saving water for soaking and salt washing. A combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the depth of the drip irrigation pipe is mostly 60-70cm underground, the spacing between the drip irrigation pipes is 40-50cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 5-10cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water penetrates into the soil through the sowing holes;

[0015] S4. Seeding:

[0016] Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation;

[0017] S5. Water-saving irrigation

[0018] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage.

[0019] The shallow water irrigation stage is from the rice seeding to the greening stage, shallow water irrigation is carried out by ground irrigation, and salt is washed at the same time. The shallow water irrigation volume is 15-20m 3 / 667m 2 ;

[0020] The intermediate water irrigation stage is from the rice greening to the jointing stage. The intermediate water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The intermediate water irrigation volume is 20-25m 3 / 667m 2 ;

[0021] The deep water irrigation stage is from booting to flowering stage, and deep water irrigation is carried out by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The deep water irrigation volume is 25-35m 3 / 667m 2 , of which underground irrigation method has an irrigation volume of 15-20m 3 / 667m 2 , the irrigation volume of ground irrigation is 10-15m 3 / 667m 2 ;

[0022] The wet irrigation stage is from flowering to rice maturity, maintaining 81-85% of the maximum water holding capacity of the soil, using a dry-wet alternating method, using ground irrigation to carry out wet irrigation, controlling soil compaction and salt return, and the irrigation volume of the wet irrigation is 10-20m 3 / 667m 2 .

[0023] From the late stage of rice maturity to harvest, water control and field drying are carried out without irrigation.

[0024] S6. Field management.

[0025] Preferably, the plants in step S1 are one or more combinations of Suaeda salsa, Medicago truncatula, Suaeda salsa or Sesbania sesbania.

[0026] Preferably, the shallow water irrigation stage is from the rice seeding and germination to the greening stage, shallow water irrigation is carried out by ground irrigation, and salt is washed at the same time. The shallow water irrigation volume is 15-20m 3 / 667m 2 ;

[0027] Preferably, the intermediate water irrigation stage is from the rice greening to the jointing stage, and the intermediate water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The intermediate water irrigation volume is 20-25m 3 / 667m 2 ;

[0028] Preferably, the deep water irrigation stage is from booting to flowering stage, and deep water irrigation is carried out by combining ground and underground irrigation, firstly irrigating by underground irrigation, and then irrigating by ground irrigation to prevent salt return. The deep water irrigation volume is 25-35m 3 / 667m 2 , of which underground irrigation method has an irrigation volume of 15-20m 3 / 667m 2 , the irrigation volume of ground irrigation is 10-15m 3 / 667m2 ;

[0029] Preferably, the wet irrigation stage is from flowering to rice maturity, maintaining 81-85% of the maximum water holding capacity of the soil, using a dry-wet alternating method, using ground irrigation to carry out wet irrigation, and controlling soil compaction and salt return. The irrigation volume of the wet irrigation is 10-20m 3 / 667m 2 .

[0030] Preferably, the field management includes watering, weeding and fertilizing.

[0031] Preferably, the underground irrigation mode and the above-ground irrigation mode share a water source.

[0032] After adopting the above method, the present invention has the following advantages:

[0033] The present invention can effectively grow rice in mild to moderate saline-alkali land by improving the soil in saline-alkali land. The underground irrigation mode and the above-ground irrigation mode of the present invention are easy to install and easy to operate in the field. Water can be irrigated according to the root growth depth of the rice. Through precise irrigation, the root zone of the rice is always kept in a light salt or salt-free environment. The method of the present invention is a water-saving method for rice in saline-alkali land. According to the natural rainfall conditions, the rice is irrigated 8-10 times during the growth period, and the irrigation amount is about 280-320m 3 / 667m 2 Compared with ordinary flood irrigation, it saves more than 50% of water. It can realize water-fertilizer integration during topdressing, save water and fertilizer, and improve water-fertilizer efficiency. It can improve water resource utilization efficiency and increase rice yield by controlling irrigation time and depth. It can be flexibly adjusted according to the water demand characteristics of rice in each growth period, so as to achieve the purpose of saving water and increasing yield. Compared with traditional continuous irrigation, it can significantly improve rainfall utilization, reduce leakage, and thus reduce water resource waste.

[0034] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the full text and the following detailed description. DETAILED DESCRIPTION

[0036] Specific embodiments of the present invention will now be mentioned in detail. Although the present invention is described in conjunction with these specific embodiments, it should be appreciated that it is not intended to limit the present invention to these specific embodiments. On the contrary, these embodiments are intended to cover substitutions, changes or equivalent embodiments that may be included in the spirit and scope of the invention defined by the claims. In the following description, a large number of specific details are set forth in order to provide a comprehensive understanding of the present invention. The present invention can be implemented without some or all of these specific details. In other cases, in order not to make the present invention unnecessarily obscure, well-known process operations are not described in detail.

[0037] When used in conjunction with "including," "methods comprising," or similar language in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0038] The present invention is further described in detail below in conjunction with the full text.

[0039] In conjunction with the full text, a method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0040] S1. Soil improvement:

[0041] For medium to heavy saline-alkali land, soil improvement should be first carried out. Plants that absorb salt and alkali should be planted to reduce the salt content in the soil. After the plants grow up, they can be directly plowed as green manure. Unfermented organic fertilizer should be applied and turned into the soil to ferment. Microorganisms will produce organic acids during the reproduction process to convert salt, thereby reducing the salt and alkali content and obtaining converted land.

[0042] S2. Land preparation and fertilization:

[0043] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0044] S3, washing salt and making soil moisture:

[0045] Before direct seeding rice with film covering, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, saving water for soaking and salt washing. A combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the depth of the drip irrigation pipe is mostly 60-70cm underground, the spacing between the drip irrigation pipes is 40-50cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 5-10cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water penetrates into the soil through the sowing holes;

[0046] S4. Seeding:

[0047] Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation;

[0048] S5. Water-saving irrigation

[0049] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage.

[0050] The shallow water irrigation stage is from the rice seeding to the greening stage, shallow water irrigation is carried out by ground irrigation, and salt is washed at the same time. The shallow water irrigation volume is 15-20m 3 / 667m 2 ;

[0051] The intermediate water irrigation stage is from the rice greening to the jointing stage. The intermediate water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The intermediate water irrigation volume is 20-25m 3 / 667m 2 ;

[0052] The deep water irrigation stage is from booting to flowering stage, and deep water irrigation is carried out by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The deep water irrigation volume is 25-35m 3 / 667m 2 , of which underground irrigation method has an irrigation volume of 15-20m 3 / 667m 2 , the irrigation volume of ground irrigation is 10-15m 3 / 667m 2 ;

[0053] The wet irrigation stage is from flowering to rice maturity, maintaining 81-85% of the maximum water holding capacity of the soil, using a dry-wet alternating method, using ground irrigation to carry out wet irrigation, controlling soil compaction and salt return, and the irrigation volume of the wet irrigation is 10-20m 3 / 667m 2 .

[0054] From the late stage of rice maturity to harvest, water control and field drying are carried out without irrigation.

[0055] S6. Field management.

[0056] Preferably, the plants in step S1 are one or more combinations of Suaeda salsa, Medicago truncatula, Suaeda salsa or Sesbania sesbania.

[0057] Preferably, the field management includes watering, weeding and fertilizing.

[0058] Preferably, the underground irrigation mode and the above-ground irrigation mode share a water source.

[0059] The wet irrigation stage adopts a dry-wet alternation method, and the water is cut off at night, so that the last water does not see the previous water. Wet irrigation can promote the timely transformation of rice from vegetative growth to reproductive growth. In reproductive growth, the straight area index is high, the functional leaves are many, the tillers are many at a time, and the root-crown ratio is large. In the milky stage, shallow wet irrigation increases the starch and cellulose content of the plants, and increases the carbon-nitrogen ratio, creating conditions for high yield.

[0060] The field management includes irrigation, weeding and fertilization. It makes the factors of water, fertilizer, air, heat and so on to be reasonably adjusted, thus improving the soil fertility.

[0061] The daily temperature variation of paddy field soil temperature is large. The temperature difference of moist irrigation is 6.4-7.3, while that of water layer flooding irrigation is only 5-6. The temperature difference between day and night: moist irrigation is 4.2-4.6, while that of flooding irrigation is 3.8-4.0. The daily temperature variation of soil temperature is large. The temperature difference between day and night from heading to milk maturity in the late growth period is 2.6-3.1 for moist irrigation and 1.6-1.7 for flooding irrigation. Shallow wet irrigation is conducive to photosynthesis when the temperature is high, and the large temperature difference between day and night is conducive to the accumulation of dry matter. Shallow wet irrigation has good light, while flooding has insufficient light.

[0062] Disease control can be achieved by applying the drug Water Diver to control Spirogyra, which can effectively control the occurrence of diseases such as Spirogyra and reduce the impact of diseases on rice growth.

[0063] The underground irrigation mode and the above-ground irrigation mode share a water source.

[0064] Specifically, the rice mechanical film-covering and direct seeding integrated machine is an existing technology, which can complete the work of soil plowing, film covering, and sowing in one operation. There are two types of rice mechanical film-covering and direct seeding integrated machines. One is to cover the film first and then sow the seeds on the film; the other is to sow the seeds first, then cover the film and spread the soil, so that the seeds can break the film and come out of the soil by themselves.

[0065] Embodiment 1:

[0066] In the specific implementation of the present invention, the underground irrigation mode also includes a pressure regulator for controlling the dripper working pressure within a suitable range (usually 1-3 kg); an air valve, which is installed at the high point of each solenoid valve control area to prevent soil impurities from entering the dripper due to siphoning when the system is closed and causing blockage. A flushing valve is installed at the end of the solenoid valve controller area to regularly flush the drip irrigation system to prevent blockage. The flushing valve can be a manual or automatic control valve. The solenoid valve is used to divide the drip irrigation system into different areas and realize automatic opening and closing. The controller is used to set the irrigation program and automatically open or close the solenoid valve to realize the automatic operation of the irrigation system. In conjunction with the irrigation meteorological station or other related sensors, the irrigation system can be more intelligently controlled. A filter is used to clean impurities in the irrigation water source to prevent blockage. Each solenoid valve controller area must be installed with a mesh or laminated filter of more than 150 meshes. If the water source is not tap water, in addition to installing a mesh or laminated filter in each solenoid valve controller area, a corresponding head filtration system needs to be configured at the head of the system. A fertilizer applicator can be rotated to apply fertilizer or chlorine through the irrigation system. Pump: If the water pressure of the irrigation system cannot meet the irrigation requirements, you may need to add a pump. Check valve: A check valve should be installed at the head of the system to prevent irrigation water from flowing back and causing water pollution or damaging pumps and other equipment.

[0067] The construction steps of drip irrigation are as follows:

[0068] 1) Install the water intake point and main pipe. The buried depth of the main pipe can be determined according to the actual local conditions.

[0069] 2) Install stop valves, solenoid valves, filters and pressure regulators, etc.

[0070] 3) Install branch pipes (water inlet pipe and drain pipe). During the installation process, block the interfaces to prevent impurities from entering.

[0071] 4) Install the drip irrigation pipe. During the installation process, block the interface to prevent impurities from entering.

[0072] 5) Install the air valve.

[0073] 6) After thoroughly flushing the branch pipe, connect the drip irrigation pipe to it.

[0074] 7) Install the flush valve and then thoroughly flush the system again.

[0075] 8) Distribution test: After installation, turn on the system and observe the water output from the dripper and the uniformity of water distribution.

[0076] 9) Trench backfilling: After the test is completed, the branch pipes and drip irrigation pipes are backfilled.

[0077] Embodiment 2:

[0078] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0079] S1. Soil improvement:

[0080] For medium to heavy saline-alkali land, soil improvement should be first carried out. The salt content in the soil can be reduced by planting salt-absorbing Suaeda salsa. After the land grows up, it can be directly plowed as green manure. Unfermented organic fertilizer should be applied and turned into the soil to ferment. Microorganisms can produce organic acids during the reproduction process to convert salt, thereby reducing salinity and obtaining converted land.

[0081] S2. Land preparation and fertilization:

[0082] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0083] S3, washing salt and making soil moisture:

[0084] Before direct seeding of rice covered with film, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 70cm underground, the spacing between the drip irrigation pipes is 50cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 10cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water infiltrates into the soil through the sowing holes;

[0085] S4. Seeding:

[0086] Choose a rice mechanical film-covering and direct-seeding machine, which first covers the film and then sows the seeds on the film. It can complete rotary tillage, fertilization, sowing, film covering, soil covering and pressing in one operation.

[0087] S5. Water-saving irrigation

[0088] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage;

[0089] S6. Field management,

[0090] From the late stage of rice maturity to harvest, water control and field sunning are carried out without irrigation;

[0091] Shallow water irrigation is carried out from the rice seeding to the greening stage. Shallow water irrigation is carried out by ground irrigation. The salt is washed off at the same time. The shallow water irrigation volume is 20m 3 / 667m 2 ;

[0092] The stage of medium water irrigation is from the greening stage to the jointing stage of rice. The medium water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The irrigation volume of the medium water is 25m 3 / 667m 2 ;

[0093] Deep water irrigation is carried out during the booting to flowering period by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The amount of deep water irrigation is 35m 3 / 667m 2 , of which underground irrigation method irrigates 20m 3 / 667m 2 , the irrigation volume of ground irrigation is 15m 3 / 667m 2 ;

[0094] During the wet irrigation stage, from flowering to rice maturity, the soil moisture is maintained at 85% of its maximum water holding capacity. Alternating dry and wet methods are used to carry out wet irrigation using ground irrigation to control soil compaction and salt return. The irrigation volume of the wet irrigation is 20m 3 / 667m 2 .

[0095] Embodiment three:

[0096] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0097] S1. Soil improvement:

[0098] For medium to heavy saline-alkali land, soil improvement should be carried out first. The salt content in the soil can be reduced by planting alfalfa that absorbs salt and alkali. After it grows, it can be directly plowed into the soil as green manure, and unfermented organic fertilizer should be applied and turned into the soil to ferment. The microorganisms will produce organic acids during the reproduction process, converting the salt content, thereby reducing the salt and alkali content and obtaining converted land.

[0099] S2. Land preparation and fertilization:

[0100] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0101] S3, washing salt and making soil moisture:

[0102] Before direct seeding rice with film covering, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 60cm underground, the spacing between the drip irrigation pipes is 40cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 5cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water infiltrates into the soil through the sowing holes;

[0103] S4. Seeding:

[0104] Choose a rice mechanical film-covering and direct-seeding machine, which first sows the seeds, then covers the film and spreads the soil, allowing the seeds to break through the film and emerge from the soil by themselves. It can complete rotary tillage, fertilization, sowing, film covering, soil covering and pressing in one operation;

[0105] S5. Water-saving irrigation

[0106] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage;

[0107] S6. Field management,

[0108] From the late stage of rice maturity to harvest, water control and field sunning are carried out without irrigation;

[0109] Shallow water irrigation is carried out from the rice seeding to the greening stage. Shallow water irrigation is carried out by ground irrigation. The salt is washed off at the same time. The shallow water irrigation volume is 15m 3 / 667m 2 ;

[0110] The stage of medium water irrigation is from the greening stage to the jointing stage of rice. The medium water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The irrigation volume of the medium water is 20m 3 / 667m 2 ;

[0111] Deep water irrigation is carried out during the booting to flowering period by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The amount of deep water irrigation is 25m 3 / 667m 2 , of which underground irrigation method irrigates 15m 3 / 667m 2 , the irrigation volume of ground irrigation is 10m 3 / 667m 2 ;

[0112] During the wet irrigation stage, from flowering to rice maturity, the soil moisture is maintained at 81% of its maximum water holding capacity. Alternating dry and wet methods are used to carry out wet irrigation using ground irrigation to control soil compaction and salt return. The irrigation volume of the wet irrigation is 10m 3 / 667m 2 .

[0113] Embodiment 4:

[0114] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0115] S1. Soil improvement:

[0116] For medium to heavy saline-alkali land, soil improvement should be carried out first. The salt content in the soil can be reduced by planting alkali-absorbing sedge. After the land grows, it can be directly plowed as green manure. Unfermented organic fertilizer should be applied and turned into the soil to ferment. Microorganisms can produce organic acids during the reproduction process to convert salt, thereby reducing salinity and obtaining converted land.

[0117] S2. Land preparation and fertilization:

[0118] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0119] S3, washing salt and making soil moisture:

[0120] Before direct seeding of rice covered with film, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 65cm underground, the spacing between the drip irrigation pipes is 45cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 8cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water infiltrates into the soil through the sowing holes;

[0121] S4. Seeding:

[0122] Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation;

[0123] S5. Water-saving irrigation

[0124] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage;

[0125] S6. Field management,

[0126] From the late stage of rice maturity to harvest, water control and field sunning are carried out without irrigation;

[0127] Shallow water irrigation is carried out from rice seeding to greening stage, using ground irrigation to carry out shallow water irrigation, and the salt is washed away at the same time. The shallow water irrigation volume is 18m 3 / 667m 2 ;

[0128] The stage of medium water irrigation is from the greening stage to the jointing stage of rice. The medium water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The irrigation volume of the medium water is 23m 3 / 667m 2 ;

[0129] Deep water irrigation is carried out during the booting to flowering period by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The amount of deep water irrigation is 28m 3 / 667m 2 , of which underground irrigation method irrigates 16m 3 / 667m 2 , the irrigation volume of ground irrigation is 12m 3 / 667m 2 ;

[0130] During the wet irrigation stage, from flowering to rice maturity, the soil moisture is maintained at 81-85% of its maximum water holding capacity. Alternating dry and wet methods are used to carry out wet irrigation using ground irrigation to control soil compaction and salt return. The irrigation volume of the wet irrigation is 15m 3 / 667m 2 .

[0131] Embodiment five:

[0132] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0133] S1. Soil improvement:

[0134] For medium to heavy saline-alkali land, soil improvement should be carried out first. The salt content in the soil can be reduced by planting alfalfa that absorbs salt and alkali. After it grows, it can be directly plowed into the soil as green manure, and unfermented organic fertilizer should be applied and turned into the soil to ferment. The microorganisms will produce organic acids during the reproduction process, converting the salt content, thereby reducing the salt and alkali content and obtaining converted land.

[0135] S2. Land preparation and fertilization:

[0136] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0137] S3, washing salt and making soil moisture:

[0138] Before direct seeding rice with film covering, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 68cm underground, the spacing between the drip irrigation pipes is 48cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 8cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the water seeps into the soil through the sowing holes;

[0139] S4. Seeding:

[0140] Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation;

[0141] S5. Water-saving irrigation

[0142] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage;

[0143] S6. Field management,

[0144] From the late stage of rice maturity to harvest, water control and field sunning are carried out without irrigation;

[0145] The shallow water irrigation stage is from the rice seeding to the greening stage. Shallow water irrigation is carried out by ground irrigation. The salt is washed off at the same time. The shallow water irrigation volume is 19m 3 / 667m 2 ;

[0146] The stage of medium water irrigation is from the greening stage to the jointing stage of rice. The medium water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The irrigation volume of the medium water is 25m 3 / 667m 2 ;

[0147] Deep water irrigation is carried out during the booting to flowering period by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The amount of deep water irrigation is 32m 3 / 667m 2 , of which underground irrigation irrigation volume is 17m 3 / 667m 2 , the irrigation volume of ground irrigation is 14m 3 / 667m 2 ;

[0148] During the wet irrigation stage, from flowering to rice maturity, the soil moisture is maintained at 81-85% of its maximum water holding capacity. Alternating dry and wet methods are used to carry out wet irrigation using ground irrigation to control soil compaction and salt return. The irrigation volume of the wet irrigation is 18m 3 / 667m 2 .

[0149] Embodiment six:

[0150] A method for water-saving cultivation of rice in saline-alkali land comprises the following steps:

[0151] S1. Soil improvement:

[0152] For medium to heavy saline-alkali land, soil improvement is first carried out. The salt content in the soil is reduced by planting sesbania, which absorbs salt and alkali. After it grows up, it can be directly plowed into the soil as green manure, and unfermented organic fertilizer is applied. It is turned into the soil and allowed to ferment. The microorganisms produce organic acids during the reproduction process, converting salt, thereby reducing salinity and obtaining converted land.

[0153] S2. Land preparation and fertilization:

[0154] Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall;

[0155] S3, washing salt and making soil moisture:

[0156] Before direct seeding of rice covered with film, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 70cm underground, the spacing between the drip irrigation pipes is 50cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 5cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the water seeps into the soil through the sowing holes;

[0157] S4. Seeding:

[0158] Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation;

[0159] S5. Water-saving irrigation

[0160] The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage;

[0161] S6. Field management,

[0162] From the late stage of rice maturity to harvest, water control and field sunning are carried out without irrigation;

[0163] Shallow water irrigation is carried out from the rice seeding to the greening stage. Shallow water irrigation is carried out by ground irrigation. The salt is washed off at the same time. The shallow water irrigation volume is 15m 3 / 667m 2 ;

[0164] The stage of medium water irrigation is from the greening stage to the jointing stage of rice. The medium water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The irrigation volume of the medium water is 20m 3 / 667m 2 ;

[0165] Deep water irrigation is carried out during the booting to flowering period by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The amount of deep water irrigation is 35m 3 / 667m 2 , of which underground irrigation method irrigates 20m 3 / 667m 2 , the irrigation volume of ground irrigation is 15m 3 / 667m 2 ;

[0166] During the wet irrigation stage, from flowering to rice maturity, the soil moisture is maintained at 81-85% of its maximum water holding capacity. Alternating dry and wet methods are used to carry out wet irrigation using ground irrigation to control soil compaction and salt return. The irrigation volume of the wet irrigation is 10m 3 / 667m 2 .

[0167] Comparative Example:

[0168] The cultivation method of Example 2 is adopted, but the difference is that no hose micro-spraying equipment is provided, and ordinary flooding irrigation technology is adopted. Example 1 is a method for deploying the present invention, and the differences between Examples 2 to 6 are different parameters and specific water consumption.

[0169] Table 1 Water consumption, yield and cost of rice production

[0170]

[0171] It can be seen from Table 1 that the rice planting method of the present invention can effectively reduce the amount of water used per mu and save nearly 70% of water.

[0172] The present invention and its embodiments are described above, and such description is not restrictive. What is shown in the full text is only one of the embodiments of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A method for water-saving cultivation of rice in saline-alkali land, characterized in that: The following steps are involved: S1. Soil improvement: For medium to heavy saline-alkali land, soil improvement should be first carried out. Plants that absorb salt and alkali should be planted to reduce the salt content in the soil. After the plants grow up, they can be directly plowed as green manure. Unfermented organic fertilizer should be applied and turned into the soil to ferment. Microorganisms will produce organic acids during the reproduction process to convert salt, thereby reducing the salt and alkali content and obtaining converted land. S2. Land preparation and fertilization: Deeply plow, level and dig drainage ditches or drainage channels for the land converted in step S1 or the saline-alkali land with a moderate or lower degree to increase soil permeability and promote the flow and drainage of water; at the same time, build water dikes around the fields to intercept and effectively utilize natural rainfall; S3, washing salt and making soil moisture: Before direct seeding of rice covered with film, the traditional large-scale field soaking and salt washing is not carried out. Instead, irrigation and salt washing are carried out simultaneously after sowing, and a combination of underground irrigation and ground irrigation is established. The underground irrigation mode is that the buried depth of the drip irrigation pipe is mostly 60-70cm underground, the spacing between the drip irrigation pipes is 40-50cm, the drip irrigation head is connected to the drip irrigation pipe, and the drip irrigation head is 5-10cm away from the ground; the ground irrigation mode is to establish an above-ground hose, the hose irrigates water on the film, and the irrigation water infiltrates into the soil through the sowing holes; S4. Seeding: Choose a rice mechanical film-covering and direct-seeding machine that can complete rotary tillage, fertilization, sowing, film covering, soil covering, and compaction in one operation; S5. Water-saving irrigation The water-saving irrigation mode includes shallow water irrigation stage, medium water irrigation stage, deep water irrigation stage and moist irrigation stage; S6. Field management, From the late stage of rice maturity to harvest, water control and field drying are carried out without irrigation.

2. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The shallow water irrigation stage is from the rice seeding to the greening stage, shallow water irrigation is carried out by ground irrigation, and salt is washed at the same time. The shallow water irrigation volume is 15-20m 3 / 667m 2 .

3. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The intermediate water irrigation stage is from the rice greening to the jointing stage. The intermediate water irrigation is carried out by underground irrigation. Underground irrigation reduces ground evaporation and improves irrigation efficiency. The intermediate water irrigation volume is 20-25m 3 / 667m 2 .

4. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The deep water irrigation stage is from booting to flowering stage, and deep water irrigation is carried out by combining ground and underground irrigation. First, underground irrigation is carried out, and then ground irrigation is carried out to prevent salt return. The deep water irrigation volume is 25-35m 3 / 667m 2 , of which underground irrigation method has an irrigation volume of 15-20m 3 / 667m 2 , the irrigation volume of ground irrigation is 10-15m 3 / 667m 2 .

5. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The wet irrigation stage is from flowering to rice maturity, maintaining 81-85% of the maximum water holding capacity of the soil, using a dry-wet alternating method, using ground irrigation to carry out wet irrigation, controlling soil compaction and salt return, and the irrigation volume of the wet irrigation is 10-20m 3 / 667m 2 .

6. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The plants in step S1 are one or more combinations of Suaeda salsa, alfalfa, Suaeda salsa or Sesbania sesbania.

7. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The field management includes watering, weeding and fertilizing.

8. The method for water-saving cultivation of rice in saline-alkali land according to claim 1, characterized in that: The underground irrigation mode and the above-ground irrigation mode share a water source.

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