A method for intercropping halophytes and forage crops in saline-alkali land

Abstract

This invention relates to a method for intercropping halophytes and forage crops in saline-alkali land. This method selects moderately to severely saline-alkali cultivated land or newly reclaimed saline-alkali wasteland in arid inland areas. Based on the principle of planting suitable crops for suitable sites, it constructs an intercropping pattern of halophytes + salt-tolerant forage crops by screening halophytes and salt-tolerant forage crops, achieving high-yield planting and improvement of the original soil in moderately to severely saline-alkali land. The method described in this invention has significant guiding value for improving the quality and efficiency of moderately to severely saline-alkali cultivated land and for the improvement and utilization of newly reclaimed saline-alkali wasteland.

Description

Technical Field

[0001] This invention discloses a method for intercropping halophytes and forage crops in saline-alkali land, specifically a method for intercropping halophytes and salt-tolerant forage crops in moderately to severely low-yield saline-alkali land. Background Technology

[0002] Xinjiang has about one-third of the country's saline-alkali land area, and nearly 40% of its existing arable land suffers from salinization, which is an important reason for the large number of low- and medium-yield fields.

[0003] Halophytes can utilize methods such as fleshy organ formation, ion compartmentalization, and osmotic regulation to remove sodium that has entered their bodies. ＋ Dilute to a non-harmful concentration to allow it to grow normally in high soil salinity. True halophytes of the Chenopodiaceae family accumulate 30-45% ash by dry weight, commonly known as salt-eating plants. Removing the absorbed soil salts by cutting the above-ground parts of these plants can reduce the salinity of saline soil. Studies have shown that planting halophytes such as Suaeda salsa, Salicornia glutinosa, Scutellaria barbata, and Suaeda salsa on saline-alkali land can remove a large amount of salt from the soil annually. Continuous planting for 2-3 years can significantly desalinate the land, bringing it to arable conditions.

[0004] Intercropping halophytes with salt-tolerant forage crops is beneficial because halophytes require salt for growth and have well-developed root systems. With the salt-dissipating and salt-suppressing effects of drip irrigation, the salt in the topsoil can be leached and desalinated, creating a micro-saline soil environment around the drip irrigation strip. This provides conditions for the growth of salt-tolerant forage crops such as sorghum or Sudan grass, thereby increasing yield and efficiency in moderately to severely saline-alkali land.

[0005] For the original planting and improvement of moderately to severely saline-alkali arable land, we will select economical halophytes and salt-tolerant crops for intercropping and relay cropping, establish a new model for the comprehensive utilization of saline-alkali land, and shift from crops adapted to saline-alkali land to the selection and breeding of salt-tolerant plants adapted to saline-alkali land, thereby tapping the potential for the development and utilization of saline-alkali land. Summary of the Invention

[0006] The purpose of this invention is to provide a method for intercropping halophytes and forage crops in saline-alkali land. This method selects moderately to severely saline-alkali cultivated land or newly reclaimed saline-alkali wasteland in arid inland areas, and based on the principle of planting the right crop for the right place, intercrops halophytes with salt-tolerant forage crops to achieve in-situ planting and improved quality and efficiency of forage crops in moderately to severely saline-alkali low-yield fields. This method constructs a new model for the comprehensive utilization of moderately to severely saline-alkali land. The method described in this invention has significant guiding value for improving the quality and efficiency of moderately to severely saline-alkali cultivated land and for the improvement and utilization of newly reclaimed saline-alkali wasteland.

[0007] The method for intercropping halophytes and forage crops in saline-alkali land according to the present invention is carried out according to the following steps:

[0008] Site selection:

[0009] a. Select a flat plot of moderately to severely saline-alkali land with a soil salt content of 8.0-15.0 g / kg in the 0-20 cm soil layer;

[0010] Crop selection:

[0011] b. Select halophytes such as Suaeda salsa or Suaeda salsa, and select salt-tolerant sorghum or Sudan grass as crops.

[0012] Pre-broadcast preparation:

[0013] c. Before sowing, plow and harrow the flat plot selected in step a to a depth of 25-30cm. Before sowing, mix the seeds of the halophyte Suaeda salsa or Suaeda salsa selected in step b with peat moss and fine sand in a volume ratio of 1:2:2 for later use.

[0014] sowing:

[0015] d. Sow in two phases. In early to mid-April, use drip irrigation with one pipe per furrow to plant halophytes. On the land leveled in step c, make shallow furrows with a spacing of 1.0-1.2 m, a depth of 10-15 cm and a width of 30-40 cm. Place the drip irrigation tape at the bottom of the furrow. Sow the mixed halophyte seeds (Suaeda salsa or Suaeda salsa) from the seed box directly on both sides of the drip irrigation tape in the furrow.

[0016] e. 18-20 days after sowing the seeds of the halophyte Suaeda salsa or Suaeda salsa in step d, when the seedlings are about 10-15cm tall, intercrop the seeds of forage crops such as sorghum or Sudan grass at a spacing of 8-10cm between the plants in the halophyte rows on both sides of the drip irrigation tape, 12-15cm away from the drip irrigation tape.

[0017] Irrigation Management:

[0018] f. For halophytes such as Suaeda salsa or Suaeda salsa, drip irrigation should begin immediately after sowing. The irrigation amount should be such that the soil moisture peak crosses the edge of the furrow, ensuring the soil within the furrow remains moist. Drip irrigation should be performed once daily. After the halophytes emerge 4-5 days after sowing, drip irrigation should be performed every 3-5 days, with the amount of water each time ensuring that the lateral soil moisture peaks of adjacent drip irrigation strips are roughly in contact. For forage crops such as sorghum or Sudan grass, drip irrigation should begin immediately after sowing to allow the seedlings to emerge. Thereafter, drip irrigation should be performed every 8-10 days, with each irrigation volume being 225-300 ml. 3 / ha, the selected forage crops such as sorghum and Sudan grass are resistant to cutting. After each harvest of the above-ground parts, timely irrigation should be carried out to promote their regrowth.

[0019] Harvesting and fertilization management:

[0020] g. After sowing salt-tolerant forage grass Sudan grass or sorghum in step e, apply 90-120 kg / ha of compound fertilizer with water to the farmland. During the jointing stage of Sudan grass or sorghum, apply 120-150 kg / ha of urea with water to the farmland.

[0021] h. When the stubble is 10-15cm long during the booting stage of Suaeda salsa or Suaeda salsa, perform the first cut. Five days after cutting, apply 90-120 kg / ha of compound fertilizer with irrigation water. After the plants enter the jointing stage, apply 120-150 kg / ha of urea with irrigation water to the farmland. When the booting stage of Suaeda salsa or Suaeda salsa begins, leave a stubble of 10-15cm and cut the plants. Repeat step h for subsequent cutting and fertilization management. Detailed Implementation Example 1

[0022] Planting experiment in moderately to severely saline-alkali land in Abati Town, Kashgar Tajik Autonomous County;

[0023] Site selection:

[0024] a. Select flat plots of moderately to severely saline-alkali wasteland with a soil salt content of 8.0 g / kg in the 0-20 cm soil layer for reclamation;

[0025] Plant selection:

[0026] b. For halophytes, choose Suaeda salsa; for forage crops, choose Sudan grass, which is more salt-tolerant.

[0027] Pre-broadcast preparation:

[0028] c. Before sowing, plow and harrow the flat plot selected in the previous step to a depth of 25 cm. Before sowing, mix the seeds of the halophyte Suaeda salsa with peat moss and fine sand in a volume ratio of 1:2:2 for later use.

[0029] d. Sow in two phases. In early to mid-April, use drip irrigation with one pipe per furrow to plant halophytes. On the land leveled in step c, make shallow furrows with a spacing of 1.0 m, a depth of 10 cm and a width of 30 cm. Place the drip irrigation tape at the bottom of the furrow and sow the mixed halophyte Suaeda salsa seeds from step c directly from the sowing box onto both sides of the drip irrigation tape in the furrow.

[0030] e. Eighteen days after sowing the seeds of the halophyte Suaeda salsa, when the seedlings are about 10 cm tall, intercrop the seeds of the forage crop Sudan grass at a spacing of 8 cm between plants in the rows of halophytes on both sides of the drip irrigation tape, 12 cm away from the drip irrigation tape.

[0031] Irrigation Management:

[0032] f. For the halophyte *Suaeda salsa*, drip irrigation should begin immediately after sowing. The irrigation volume should be such that the soil moisture peak crosses the edge of the furrow, ensuring the soil within the furrow remains moist. To maintain soil moisture in the sowing area, drip irrigation should be performed once daily. After *Suaeda salsa* seedlings emerge (4 days after sowing), drip irrigation should begin every 3 days, with each irrigation volume ensuring the lateral soil moisture peaks of adjacent drip irrigation strips are roughly aligned. For the forage crop *Sudangrass*, drip irrigation should begin immediately after sowing to allow seedlings to emerge, followed by drip irrigation every 8 days, with each irrigation volume being 225 m³. 3 / ha, the selected forage crop, Sudan grass, is tolerant of cutting and can be harvested 3-5 times in Xinjiang. After each harvest of the above-ground parts, timely irrigation should be carried out to promote its regrowth.

[0033] Harvesting and fertilization management:

[0034] g. After sowing salt-tolerant forage grass Sudan grass, apply 90 kg / ha of compound fertilizer with water to the farmland. During the jointing stage of Sudan grass, apply 120 kg / ha of urea with water to the farmland.

[0035] h. When the stubble is 10 cm long during the booting stage of Suaeda salsa, the first cut is made. Five days after the cut, 90 kg / ha of compound fertilizer with macronutrients is applied with irrigation water to promote growth. After the regrowth plants enter the jointing stage, 120 kg / ha of urea is applied with irrigation water to the farmland. When the booting stage of Suaeda salsa begins, the stubble is left at 10 cm and the plant is cut again. Subsequent cutting and fertilization management are repeated from step h.

[0036] Field yield measurements showed that the intercropping system of Suaeda salsa and Sudan grass was harvested a total of 5 times. The above-ground parts were generally cut when the plants were about 110-120cm tall, leaving a 10cm stubble. The first harvest was on June 10th, and subsequent harvests were generally once a month apart. The first harvest yielded 3300 kg / mu of green fodder, the second 3100 kg / mu, the third 2800 kg / mu, the fourth 2400 kg / mu, and the fifth 2200 kg / mu. The first and second harvests yielded a mixture of Suaeda salsa and Sudan grass, while the third, fourth, and fifth harvests yielded mainly Sudan grass green fodder. It can be seen that the yield of each harvest gradually decreased with the increase in the number of harvests.

[0037] Example 2

[0038] Site selection:

[0039] a. Select a flat plot of moderately to severely saline-alkali land with a soil salt content of 12.0 g / kg in the 0-20 cm soil layer;

[0040] Crop selection:

[0041] b. Select Suaeda salsa as the halophyte and salt-tolerant sorghum as the crop.

[0042] Pre-broadcast preparation:

[0043] c. Before sowing, plow and harrow the flat plot selected in the previous step to a depth of 28 cm. Before sowing, mix the seeds of the halophyte Suaeda salsa with peat moss and fine sand in a volume ratio of 1:2:2 for later use.

[0044] sowing:

[0045] d. Sow in two phases. In early to mid-April, use drip irrigation with one pipe per furrow to plant halophytes. On the land leveled in step c, make shallow furrows 1.2 m apart, 15 cm deep and 40 cm wide. Place the drip irrigation tape at the bottom of the furrows and sow the mixed halophyte Suaeda salsa seeds from step c directly from the sowing box onto both sides of the drip irrigation tape in the furrows.

[0046] e. Twenty days after sowing the seeds of the halophyte Suaeda salsa, when the seedlings are about 15 cm tall, intercrop sorghum seeds, which are forage crops, are sown in the rows of halophytes on both sides of the drip irrigation tape at a distance of 15 cm from the drip irrigation tape and at a plant spacing of 10 cm.

[0047] Irrigation Management:

[0048] f. Drip irrigation should be implemented immediately after sowing of the halophyte Suaeda salsa seeds. The irrigation amount should be such that the soil moisture peak crosses the edge of the furrow, ensuring that the soil in the furrow remains moist. To maintain soil moisture in the sowing area, drip irrigation should be carried out once a day. After the halophytes emerge 5 days after sowing, drip irrigation should be carried out once every 5 days, with the amount of water each time ensuring that the lateral soil moisture peaks of adjacent drip irrigation strips are roughly in contact. When intercropping sorghum, a forage crop, in the rows of halophytes, drip irrigation should be carried out immediately after sowing until the seedlings emerge, and then drip irrigation should be carried out once every 10 days thereafter, with each irrigation amount being 300 m³. 3 / ha, the selected forage crop sorghum is resistant to cutting and can be harvested 3-5 times in Xinjiang. After each harvest of the above-ground parts, timely irrigation should be carried out to promote its regrowth.

[0049] Harvesting and fertilization management:

[0050] g. After sowing salt-tolerant forage sorghum, apply 120 kg / ha of compound fertilizer with macro-elements to the farmland with irrigation water. During the jointing stage of sorghum, apply 150 kg / ha of urea to the farmland with irrigation water.

[0051] h. When the stubble is 15 cm long during the heading stage of Suaeda salsa in saline-alkali soil, the first cutting is carried out. Five days after cutting, 120 kg / ha of compound fertilizer with macro-elements is applied with irrigation water to promote growth. After the regrowth plants enter the jointing stage, 150 kg / ha of urea is applied with irrigation water to the farmland. When the stubble enters the heading stage of Suaeda salsa in saline-alkali soil, the stubble is cut again with a 15 cm long stubble. Subsequent cutting and fertilization management are repeated from step h. Example 3

[0052] In 2020, the afforestation and emission reduction operation area in Karamay;

[0053] Site selection:

[0054] a. Select a flat plot of moderately to severely saline-alkali land with a soil salt content of 10g / kg in the 0-20cm soil layer;

[0055] Crop selection:

[0056] b. Select Suaeda salsa as the halophyte and Sudan grass as the crop;

[0057] Pre-broadcast preparation:

[0058] c. Before sowing, plow and harrow the flat plot selected in step a to a depth of 27 cm. Before sowing, mix the seeds of the halophyte Suaeda salsa with peat moss and fine sand in a volume ratio of 1:2:2 for later use.

[0059] sowing:

[0060] d. Sow in two phases. In early to mid-April, use drip irrigation with one pipe per furrow to plant halophytes. On the land leveled in step c, make shallow furrows with a spacing of 1.0 m, a depth of 12 cm and a width of 35 cm. Place the drip irrigation tape at the bottom of the furrow and sow the mixed halophyte Suaeda salsa seeds from step c directly from the sowing box onto both sides of the drip irrigation tape in the furrow.

[0061] e. Twenty days after sowing the seeds of the halophyte Suaeda salsa, when the seedlings are about 12 cm tall, intercrop the seeds of forage crop Sudan grass at a spacing of 8 cm between the plants in the rows of Suaeda salsa on both sides of the drip irrigation tape, 13 cm away from the drip irrigation tape.

[0062] Irrigation Management:

[0063] f. Drip irrigation should begin immediately after sowing the seeds of the halophyte *Suaeda salsa*. The irrigation volume should be such that the soil moisture peak crosses the edge of the furrow, ensuring the soil within the furrow remains moist. To maintain soil moisture in the sowing area, drip irrigation should be performed once daily. After the halophytes emerge 5 days after sowing, drip irrigation should begin every 5 days, with each irrigation volume ensuring the lateral soil moisture peaks of adjacent drip irrigation strips are roughly aligned. For intercropping the forage crop *Suaeda salsa* within the rows of halophyte *Suaeda salsa*, drip irrigation should begin immediately after sowing and once seedlings emerge, followed by drip irrigation every 9 days, with each irrigation volume being 250 m³. 3 / ha, the selected forage crop, Sudan grass, is tolerant of cutting and can be harvested 3-5 times in Xinjiang. After each harvest of the above-ground parts, timely irrigation should be carried out to promote its regrowth.

[0064] Harvesting and fertilization management:

[0065] g. After sowing salt-tolerant forage grass Sudan grass, apply compound fertilizer at a rate of 100 kg / ha with irrigation water. At the Sudan grass jointing stage, apply urea at a rate of 120 kg / ha with irrigation water.

[0066] h. During the booting stage, leave a stubble of 12 cm and perform the first cut. Five days after cutting, apply 100 kg / ha of compound fertilizer with water to promote growth. After the regrowth plants enter the jointing stage, apply 13 kg / ha of urea with water. During the booting stage, leave a stubble of 13 cm and cut again. Repeat step h for subsequent cutting and fertilization management.

[0067] Field yield measurements showed that the intercropping system of Suaeda salsa and Suaeda salsa was harvested three times. The above-ground parts were cut with a stubble of 15 cm when the plants were about 180 cm tall. The first harvest was on July 3, the second on August 24, and the third on October 3. The first harvest yielded 4600 kg / mu of green fodder, the second 4200 kg / mu, and the third 3500 kg / mu. The first harvest was a mixture of Suaeda salsa and Suaeda salsa, while the second and third harvests were mainly Suaeda salsa. The yield of each harvest gradually decreased with the number of harvests.

[0068] Example 4

[0069] Site selection:

[0070] a. Select a flat plot of moderately to severely saline-alkali land with a soil salt content of 15.0 g / kg in the 0-20 cm soil layer;

[0071] Crop selection:

[0072] b. Select Suaeda salsa as the halophyte and salt-tolerant sorghum as the crop.

[0073] Pre-broadcast preparation:

[0074] c. Before sowing, plow and harrow the flat plot selected in step a to a depth of 30 cm. Before sowing, mix the seeds of the halophyte Suaeda salsa with peat moss and fine sand in a volume ratio of 1:2:2 for later use.

[0075] sowing:

[0076] d. Sow in two phases. In early to mid-April, use drip irrigation with one pipe per furrow to plant halophytes. On the land leveled in step c, make shallow furrows with a spacing of 1.0 m, a depth of 14 cm and a width of 38 cm. Place the drip irrigation tape at the bottom of the furrow and sow the mixed halophyte Suaeda salsa seeds from step c directly from the sowing box onto both sides of the drip irrigation tape in the furrow.

[0077] e. Eighteen days after sowing the seeds of the halophyte Suaeda salsa, when the seedlings are about 14cm tall, intercrop sorghum seeds, which are forage crops, are sown at a spacing of 9cm between plants in the rows of Suaeda salsa on both sides of the drip irrigation belt, 14cm away from the drip irrigation belt.

[0078] Irrigation Management:

[0079] f. Drip irrigation should begin immediately after sowing the seeds of the halophyte *Suaeda salsa*. The irrigation volume should be such that the soil moisture peak crosses the edge of the furrow, ensuring the soil within the furrow remains moist. To maintain soil moisture in the sowing area, drip irrigation should be performed once daily. After the halophytes emerge (4 days after sowing), drip irrigation should begin every 5 days, with each irrigation volume ensuring the lateral soil moisture peaks of adjacent drip irrigation strips are roughly aligned. When intercropping sorghum (a forage crop) within the rows of *Suaeda salsa*, drip irrigation should begin immediately after sowing and once the seedlings emerge, followed by drip irrigation every 10 days, with each irrigation volume being 280 ml. 3 / ha, the selected forage crop sorghum is resistant to cutting and can be harvested 3-5 times in Xinjiang. After each harvest of the above-ground parts, timely irrigation should be carried out to promote its regrowth.

[0080] Harvesting and fertilization management:

[0081] g. After sowing salt-tolerant forage sorghum, apply 110 kg / ha of compound fertilizer with water to the farmland. During the jointing stage of sorghum, apply 140 kg / ha of urea with water to the farmland.

[0082] h. When the stubble is 13 cm long during the booting stage of Suaeda salsa, the first cut is made. Five days after cutting, 120 kg / ha of compound fertilizer with macro-elements is applied with irrigation water to promote growth. After the regrowth plants enter the jointing stage, 150 kg / ha of urea is applied with irrigation water to the farmland. When the booting stage of Suaeda salsa begins, the stubble is 15 cm long, and the Suaeda salsa is cut again. Subsequent cutting and fertilization management are the same as step h.

Claims

1. A method for interplanting a salt-tolerant plant and a forage crop in a saline-alkali soil, characterized in that The following steps are taken: Plot selection: a. Select a flat plot of medium to severe saline-alkali land with soil salt content of 8.0-15.0 g / kg in the 0-20 cm soil layer; Plant selection: b. Select a halophyte as Suaeda salsa or Halocnemum strobilaceum, and a crop that is salt-tolerant such as sorghum or sudan grass; Pre-seeding preparation: c. Before sowing, plow and harrow the flat plot selected in step a to a depth of 25-30 cm. Mix the seeds of the halophyte selected in step b with peat soil and fine sand at a volume ratio of 1:2:2 for use; Sowing: d. Sow in two stages. In the first ten days of April, plant the halophyte using drip irrigation with a drip irrigation belt in a one-ditch-one-pipe manner. Create a shallow ditch in the land plowed and harrowed in step c with a spacing of 1.0-1.2 m, a depth of 10-15 cm, and a width of 30-40 cm. Place the drip irrigation belt at the bottom of the ditch, and directly sow the seeds of the halophyte mixed in step c on both sides of the drip irrigation belt from a sowing box; e. After 18-20 days of sowing the seeds of the halophyte in step d, when the seedlings are about 10-15 cm tall, sow the seeds of the forage crop, sorghum or sudan grass, at a spacing of 8-10 cm from the drip irrigation belt on both sides of the halophyte row; Water management: f、Saltbush or hard branch alkali seed after sowing drip irrigation, irrigation amount with soil wet peak over the ditch along, to protect the soil wet in the ditch as the standard, drip irrigation 1 time per day, after 4-5 days of salt plant seedlings, 3-5 days of drip water 1 time, each irrigation amount with adjacent drip irrigation belt lateral soil wet peak basically connected; 3 / ha, the selected forage grasses, kudzu and sudan grass, cut every time after the aboveground part, and promptly irrigation to promote its regrowth; Mowing and fertilization management: g. After sowing the salt-tolerant forage, sudan grass or sorghum, in step e, apply a large amount of element compound fertilizer at a rate of 90-120 kg / ha to the farmland with water dripping. At the jointing stage of the sudan grass or sorghum, apply urea at a rate of 120-150 kg / ha to the farmland with water dripping; h. At the booting stage of the Suaeda salsa or Halocnemum strobilaceum, mow the plants to a stubble height of 10-15 cm. Five days after mowing, apply element compound fertilizer at a rate of 90-120 kg / ha with water dripping. At the jointing stage of the replanted plants, apply urea at a rate of 120-150 kg / ha to the farmland with water dripping. At the booting stage of the Suaeda salsa or Halocnemum strobilaceum, mow the plants to a stubble height of 10-15 cm. Repeat the mowing and fertilization management in step h.