Method for rapidly planting leymus chinensis in moderate-severe soda saline-alkali soil based on degradable nutrition pots

Abstract

The invention discloses a method for rapidly planting leymus chinensis in moderate-severe soda saline-alkali soil based on degradable nutrition bowls, and relates to a method for rapidly planting leymus chinensis in soda saline-alkali soil. The invention aims to solve the problems of low planting survival rate and slow community expansion of the leymus chinensis in the saline-alkali soil. The method comprises the following steps: 1, seed germination; 2, device preparation and matrix filling; 3, cultivating leymus chinensis seedlings in batches; 4, land leveling; 5, field planting; 7, field management. According to the method, saline-alkali stress is effectively relieved, the root domain growth microenvironment is improved, the recovery period is shortened, the cost is low, environment friendliness is achieved, compared with a traditional method, the survival rate can be remarkably increased, plant growth is promoted, and therefore the time required for building the leymus chinensis community to reach 30-50% is shortened to 1-2 years from 3 years in general. The invention belongs to the technical field of ecological restoration of degraded grassland.

Description

Technical Field

[0001] This invention relates to a method for rapid establishment of Leymus chinensis in soda saline-alkali land, belonging to the field of ecological restoration technology for degraded grassland. Background Technology

[0002] Leymus chinensis is a dominant species in the temperate grasslands of northern my country, possessing both high-quality forage value and ecological functions such as soil fixation and fertility improvement, playing a crucial role in maintaining the structural stability and functional integrity of grassland ecosystems. However, due to multiple factors such as overgrazing, unreasonable reclamation, and climate change, the degradation problems of salinization and desertification in northern grasslands are becoming increasingly severe, becoming a core bottleneck restricting grassland ecological restoration and livestock development. In the process of saline-alkali land ecological restoration, traditional transplanting methods face significant challenges: seedling roots are directly exposed to the saline-alkali environment, easily leading to dehydration and death due to osmotic stress; while transplanting using conventional plastic seedling pots can easily cause root damage during the removal process and cannot alleviate the saline-alkali stress in the rhizosphere microenvironment during the initial planting stage. Current technologies typically determine the transplanting time based on a fixed number of cultivation days (e.g., 50-60 days), failing to fully consider the physiological differences between individual plants. For Leymus chinensis, the key to its successful establishment and community expansion in saline-alkali land lies in the asexual reproduction and expansion capacity of its rhizomes. Transplanting too early results in insufficient root and stem development and weak resistance; transplanting too late easily leads to root entanglement and aging, and decreased adaptability. Leymus chinensis has a low survival rate and slow community expansion in saline-alkali land. Therefore, it is urgent to develop a technical method that integrates the application of new materials and plant growth characteristics to achieve precise determination of transplanting timing and efficient establishment of Leymus chinensis, promoting rapid seedling growth and stable community establishment in saline-alkali environments. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problems of low survival rate and slow community expansion of Leymus chinensis in saline-alkali land, and to provide a rapid planting method for Leymus chinensis in moderately to severely soda saline-alkali land based on biodegradable nutrient pots.

[0004] The following is a rapid cultivation method for Leymus chinensis in moderately to severely soda-saline-alkali land using biodegradable nutrient pots:

[0005] I. Seed germination: Select salt-tolerant sheepgrass seeds, weigh 5-10g of seeds with a purity >80% and place them in a 500mL beaker. Add 200-300mL of water, seal with plastic wrap, and activate in a refrigerator at 4℃ for 1 week, changing the water 1-2 times during this period. After activation, transfer to a petri dish lined with moist filter paper, seal with plastic wrap, and germinate at alternating temperatures of 16℃ for 10-18 hours and 28℃ for 6-14 hours daily for 3-7 days to obtain white seeds. Alternatively, after alternating temperature germination, seedlings can be obtained by vegetative growth in a hydroponic system for 30 days.

[0006] II. Device Preparation and Matrix Filling: A cylindrical micro root zone device is made of biodegradable material and filled with a non-salt-alkali matrix. The matrix filling volume accounts for 85-90% of the volume of the micro root zone device. Ensure that the matrix is ​​filled evenly and fully compacted to avoid internal voids.

[0007] III. Mass cultivation of Leymus chinensis seedlings:

[0008] Method 1: Sow the white seeds obtained in step 1 directly into the substrate of the micro-root zone device. Sow 3-5 seeds in each micro-root zone device at a depth of 1-2cm. Water until the non-saline-alkali substrate is completely saturated. Then, place the device in an environment of 18-28℃ for cultivation. Keep the non-saline-alkali substrate moist during the cultivation period until the rhizomes penetrate the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will result in a device-seedling complex with rhizomes penetrating the micro-root zone device.

[0009] Method 2: Select healthy seedlings with a height of 5-10cm and 2-4 true leaves. Plant one seedling in each micro-root zone device. After planting, water thoroughly and place in an environment of 18-28℃ for cultivation. During the cultivation period, keep the non-salt-alkali substrate moist until the rhizome penetrates the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will obtain the device-seedling complex with rhizome penetrating the micro-root zone device.

[0010] IV. Land leveling: For the soda saline-alkali grassland to be restored, deep loosening, shallow rotary tillage, and heavy harrowing and leveling operations are carried out in sequence to remove gravel and weeds from the plot.

[0011] V. On-site planting: The device-seedling complex with rhizomes penetrating the micro root zone obtained in step 3 is transported to the soda saline-alkali grassland to be restored. Plant the seedlings in holes at a preset density of 1800-2200 seedlings per acre and a spacing of 50-60cm between seedlings. The holes should be 15-18cm deep. After planting, cover the seedlings with soil up to 1-1.5cm from the top of the micro root zone and gently compact the soil to ensure that the micro root zone is in close contact with the surrounding soil.

[0012] VII. Field Management: If there is no effective rainfall within 2 days after transplanting, water should be replenished to the transplanting area; weed control should be implemented during the plant growth period to ensure the establishment and growth of seedlings, thus completing the rapid establishment of Leymus chinensis in soda saline-alkali land using biodegradable nutrient pots.

[0013] The micro root zone device described in step two is cylindrical with a diameter of 8-12cm, a height of 15-20cm, and a wall thickness of 5-8mm.

[0014] The biodegradable material described in step two is made from corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum, wherein the mass ratio of corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum is 3:2:4:1.

[0015] The non-saline-alkali substrate mentioned in step three is non-saline-alkali garden soil with a pH value of 7.0-8.0.

[0016] The filling volume described in step two accounts for 86% of the volume of the micro root domain device.

[0017] This invention utilizes biodegradable materials to prepare a root zone device, enabling "integrated planting with the device," eliminating the need to remove or disturb the root ball. In the early stages of planting, the device forms a physical salt barrier, effectively isolating the seedlings from the stress of external saline-alkali soil and providing a stable environment for root establishment. Later, it gradually degrades in the natural soil environment, avoiding root damage problems associated with traditional transplanting from pots and completely eliminating the white pollution caused by plastic seedling pots, thus achieving a harmonious balance between "short-term root zone protection" and "long-term environmental safety."

[0018] This invention breaks through the traditional experience-based transplanting determination model that relies on fixed cultivation days, and for the first time proposes using the root penetration cultivation device as an observable biological transplanting signal. This morphological indicator can directly characterize that the plant's root system has acquired the mechanical penetration ability and stress-resistant physiological activity to adapt to saline-alkali habitats. It can effectively resist the mechanical resistance and salt-alkali stress of the saline-alkali soil outside the device, realizing precise and physiologically driven transplanting decisions for Leymus chinensis from the seedling stage to the planting stage in saline-alkali land, improving the scientific nature of transplanting timing and the stability of planting survival rate.

[0019] The core technical advantages of this invention are reflected in two aspects:

[0020] 1) Nursery pots are prepared using biodegradable materials to create an independent root zone microenvironment that can isolate external salt and alkali, thus providing protection for seedling root development;

[0021] 2) This method innovatively proposes a biological criterion of "root and stem buds penetrating the pot," precisely defining the transplanting time. It fully utilizes the strong asexual reproduction characteristics of Leymus chinensis roots and stems. After cultivating robust seedlings with strong roots in the nutrient pot, the entire plant is transplanted with the pot intact once the roots and stems have the ability to penetrate. The biodegradable pot protects the core root system from the stress of high salinity and alkalinity while allowing strong root and stem buds to break through and take root, achieving a synergistic effect of "core protection + peripheral expansion," significantly improving the survival rate and community expansion speed of Leymus chinensis establishment in moderately and severely saline-alkali lands.

[0022] The beneficial effects of this invention are:

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Effectively alleviates saline-alkali stress: The biodegradable root zone device provides physical isolation for the seedling roots during the critical period of transplanting, effectively blocking the direct damage from the surrounding saline-alkali soil, and fundamentally solving the core problem of low seedling survival rate in traditional transplanting methods.

[0025] 2. Improved root zone microenvironment: The non-salt-alkali substrate filling the device provides seedlings with a breathable, water-retaining, and nutrient-rich growing space, effectively promoting early tillering and biomass accumulation, laying a solid foundation for their subsequent adaptation to saline-alkali stress in the wild.

[0026] 3. Shortened recovery period: This invention significantly improves establishment efficiency through the synergistic effect of "root zone protection and microenvironment optimization." Compared with traditional methods, it can significantly improve the survival rate and promote plant growth, thereby shortening the time required for Leymus chinensis communities to achieve a coverage of 30-50% from the usual 3 years to 1-2 years.

[0027] 4. Low cost and environmentally friendly: The device uses biodegradable materials, making it inexpensive and capable of decomposing in the natural environment without secondary pollution. The entire method is simple to operate, easy to standardize and promote, and offers both good economic and ecological benefits. This method effectively solves the problems of low survival rate, slow seedling establishment, and slow expansion associated with traditional Leymus chinensis transplanting. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the micro root domain device of the present invention. In the figure, 1 represents the central baseline of the device, 2 represents the outer wall made of biodegradable material, 3 represents the non-salt-alkali matrix filling layer, and 4 represents the water seepage hole.

[0029] Figure 2 This is a comparison chart of Shepherd's purse plant heights under different substrates in Example 1;

[0030] Figure 3 This is a comparison chart of the number of tillers in Leymus chinensis plants under different substrates in Example 1;

[0031] Figure 4 This is a comparison chart of the survival rate of Leymus chinensis transplanted 60 days after transplanting under moderate salinity conditions in Example 2;

[0032] Figure 5 This is a comparison chart of the number of tillers per plant of Leymus chinensis 60 days after transplanting under moderate salinity conditions in Example 2;

[0033] Figure 6 This is a comparison chart of Leymus chinensis plant height 60 days after transplanting under moderate salinity conditions in Example 2;

[0034] Figure 7 This is a comparison chart of the survival rate of Leymus chinensis transplanted 60 days after transplanting under severe saline-alkali conditions in Example 3;

[0035] Figure 8 This is a comparison chart of the number of tillers per plant of Leymus chinensis 60 days after transplanting under severe saline-alkali conditions in Example 3;

[0036] Figure 9This is a comparison chart of the height of Leymus chinensis plants 60 days after transplanting under severe saline-alkali conditions in Example 3. Detailed Implementation

[0037] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0038] Specific Implementation Method 1: This implementation method is based on a rapid cultivation method for Leymus chinensis in moderately to severely sodium-saline-alkali land using biodegradable nutrient pots, as follows:

[0039] I. Seed germination: Select salt-tolerant sheepgrass seeds, weigh 5-10g of seeds with a purity >80% and place them in a 500mL beaker. Add 200-300mL of water, seal with plastic wrap, and activate in a refrigerator at 4℃ for 1 week, changing the water 1-2 times during this period. After activation, transfer to a petri dish lined with moist filter paper, seal with plastic wrap, and germinate at alternating temperatures of 16℃ for 10-18 hours and 28℃ for 6-14 hours daily for 3-7 days to obtain white seeds. Alternatively, after alternating temperature germination, seedlings can be obtained by vegetative growth in a hydroponic system for 30 days.

[0040] II. Device Preparation and Matrix Filling: A cylindrical micro root zone device is made of biodegradable material and filled with a non-salt-alkali matrix. The matrix filling volume accounts for 85-90% of the volume of the micro root zone device. Ensure that the matrix is ​​filled evenly and fully compacted to avoid internal voids.

[0041] III. Mass cultivation of Leymus chinensis seedlings:

[0042] Method 1: Sow the white seeds obtained in step 1 directly into the substrate of the micro-root zone device. Sow 3-5 seeds in each micro-root zone device at a depth of 1-2cm. Water until the non-saline-alkali substrate is completely saturated. Then, place the device in an environment of 18-28℃ for cultivation. Keep the non-saline-alkali substrate moist during the cultivation period until the rhizomes penetrate the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will result in a device-seedling complex with rhizomes penetrating the micro-root zone device.

[0043] Method 2: Select healthy seedlings with a height of 5-10cm and 2-4 true leaves. Plant one seedling in each micro-root zone device. After planting, water thoroughly and place in an environment of 18-28℃ for cultivation. During the cultivation period, keep the non-salt-alkali substrate moist until the rhizome penetrates the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will obtain the device-seedling complex with rhizome penetrating the micro-root zone device.

[0044] IV. Land leveling: For the soda saline-alkali grassland to be restored, deep loosening, shallow rotary tillage, and heavy harrowing and leveling operations are carried out in sequence to remove gravel and weeds from the plot.

[0045] V. On-site planting: The device-seedling complex with rhizomes penetrating the micro root zone obtained in step 3 is transported to the soda saline-alkali grassland to be restored. Plant the seedlings in holes at a preset density of 1800-2200 seedlings per acre and a spacing of 50-60cm between seedlings. The holes should be 15-18cm deep. After planting, cover the seedlings with soil up to 1-1.5cm from the top of the micro root zone and gently compact the soil to ensure that the micro root zone is in close contact with the surrounding soil.

[0046] VII. Field Management: If there is no effective rainfall within 2 days after transplanting, water should be replenished to the transplanting area; weed control should be implemented during the plant growth period to ensure the establishment and growth of seedlings, thus completing the rapid establishment of Leymus chinensis in soda saline-alkali land using biodegradable nutrient pots.

[0047] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the micro root zone device described in step two is cylindrical with a diameter of 8-12cm, a height of 15-20cm, and a wall thickness of 5-8mm. Everything else is the same as in Specific Implementation Method One.

[0048] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the biodegradable material described in step two is made from corn stalks, decomposed rice husks, a gelling agent, and desulfurized gypsum, wherein the mass ratio of corn stalks, decomposed rice husks, a gelling agent, and desulfurized gypsum is 3:2:4:1. Everything else is the same as in Specific Implementation Method One or Two.

[0049] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the non-saline-alkali substrate mentioned in step three is non-saline-alkali garden soil with a pH value of 7.0-8.0. Everything else is the same as in Specific Implementation Methods One to Three.

[0050] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the filling volume described in step two accounts for 86% of the volume of the micro root domain device. Everything else is the same as in Specific Implementation Methods One to Four.

[0051] The effects of the present invention are verified using the following embodiments:

[0052] Example 1:

[0053] The following is a rapid cultivation method for Leymus chinensis in moderately and severely soda-saline-alkali land using biodegradable nutrient pots:

[0054] I. Seed Germination: Select salt-tolerant sheepgrass seeds, weigh 5g of seeds with a purity >80% and place them in a 500mL beaker, add 200mL of water, seal with plastic wrap and activate in a refrigerator at 4℃ for 1 week, changing the water twice during this period. After activation, transfer to a 9cm petri dish lined with moist filter paper, seal with plastic wrap, and germinate at varying temperatures for 7 days under conditions of 16℃ for 10 hours and 28℃ for 14 hours daily to obtain white seeds. After 30 days of vegetative growth in a hydroponic system, the seedlings will reach 4-5 true leaves and a height of 10-20cm.

[0055] II. Device Preparation and Substrate Filling: Cylindrical micro-root domain devices were fabricated using biodegradable materials. Two control groups were established by filling the micro-root domain devices with non-saline-alkali and saline-alkali substrates, respectively. The filling volume was 85% of the micro-root domain device volume, ensuring uniform filling and thorough compaction to avoid internal voids.

[0056] 3. Plant Expansion Simulation: Place the miniature root zone device filled with substrate in the center of a 17cm diameter flowerpot, and then fill the area around the device with saline-alkali soil until it is 1-1.5cm below the top of the device to simulate the conditions for the roots to expand outward in a saline-alkali environment.

[0057] IV. Seedling transplanting: Carefully lift the seedlings obtained in step one with a small metal shovel and transplant them into the miniature root zone device. Then water them thoroughly to ensure that the substrate in the entire device is moist.

[0058] V. Daily Management and Observation: Place the flowerpots in a controlled greenhouse environment and maintain suitable temperature and light conditions; weed regularly and water to keep the substrate moist and avoid salt accumulation in the root zone; record plant height, number of tillers and other growth indicators 60 days after transplanting, and observe whether the new tillers penetrate the root zone and expand outward.

[0059] Implementation effect

[0060] Statistical results 60 days after planting showed that, under conditions where the surrounding area of ​​the micro-root zone device was saline-alkali soil, the treatment group using the micro-root zone device of this invention and filled with non-saline-alkali substrate had an average plant height of 43.3 cm and 30 new tillers; while the control group filled with saline-alkali substrate had an average plant height of only 14.1 cm and 10 new tillers. Furthermore, the number of new tillers outside the device in the non-saline-alkali substrate treatment group was approximately twice that of the control group (14 and 5 respectively). These results indicate that filling the micro-root zone device with non-saline-alkali substrate can significantly promote the height growth and tiller proliferation of Leymus chinensis, and facilitate root expansion, effectively alleviating the stress effects of the surrounding saline-alkali soil.

[0061] Example 2:

[0062] This embodiment was implemented in Dayang Town, Dongfeng County, Liaoyuan City, Jilin Province. This area has a temperate continental monsoon climate with an average annual precipitation of about 650 mm and an average annual temperature of about 5.2℃. The experimental site was abandoned land that had been fallow for 5 years. The soil type was dark brown soil. Due to the lack of effective management, it showed a moderate trend of salinization. The vegetation was mainly annual weeds with a coverage of less than 30%.

[0063] The following is a rapid cultivation method for Leymus chinensis in moderately and severely soda-saline-alkali land using biodegradable nutrient pots:

[0064] I. Seed germination: Salt-tolerant sheepgrass seeds were selected. Using an electronic balance with a sensitivity of 0.1g, 5g of seeds with a purity >80% were weighed and placed in a 500mL beaker. 200mL of water was added, and the beaker was sealed with plastic wrap. The beaker was then activated in a refrigerator at 4℃ for 1 week, during which the water was changed twice. After activation, the beaker was transferred to a 9cm petri dish lined with moist filter paper, sealed with plastic wrap, and germinated for 7 days under alternating temperature conditions of 16℃ for 18 hours and 28℃ for 6 hours daily to obtain seeds with white sprouts.

[0065] II. Device Preparation and Substrate Filling: A cylindrical micro root zone device is made of biodegradable material and filled with a non-salt-alkali substrate, with the filling volume accounting for 86% of the volume of the micro root zone device. Ensure that the substrate is filled evenly and fully compacted to avoid internal voids.

[0066] III. Mass cultivation of Leymus chinensis seedlings:

[0067] The white seeds obtained in step one were sown directly into the substrate of the micro-root zone device. Five seeds were sown in each micro-root zone device at a depth of 2 cm. After watering until the non-salt-alkali substrate was completely saturated, the plants were placed in an environment of 18℃ for cultivation. During the cultivation period, the substrate was kept moist until the rhizomes penetrated the device wall, the plant height was 30-60 cm and the number of tillers was 5-15, thus obtaining the device-seedling complex with rhizomes penetrating the micro-root zone device.

[0068] IV. Land leveling: For the soda saline-alkali grassland to be restored, deep loosening, shallow rotary tillage, and heavy harrowing and leveling operations are carried out in sequence to remove gravel and weeds from the plot.

[0069] V. On-site planting: The device-seedling complex with rhizomes penetrating the micro root zone obtained in step 3 is transported to the moderately saline-alkali grassland to be restored. Planting is carried out in the plot treated in step 4 at a preset density of 1800 plants per acre and a plant spacing of 50cm. The holes are 15cm deep. After planting, the soil is covered to 1cm from the top of the micro root zone and gently compacted to ensure that the micro root zone is in close contact with the surrounding soil.

[0070] VII. Field Management: If there is no effective rainfall within 2 days after transplanting, water should be replenished to the transplanting area; weed control should be implemented during the plant growth period to ensure the establishment and growth of seedlings, thus completing the rapid establishment of Leymus chinensis in moderately soda saline-alkali land in biodegradable nutrient pots.

[0071] The micro root domain device described in step two is cylindrical with a diameter of 8cm, a height of 15cm, and a wall thickness of 5mm.

[0072] The biodegradable material described in step two is made from corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum, wherein the mass ratio of corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum is 3:2:4:1.

[0073] The non-saline-alkali substrate mentioned in step three is non-saline-alkali garden soil with a pH value of 7.0.

[0074] In this embodiment, the control group will use bare-root seedlings cultivated in non-saline-alkali substrate seedling trays for 60 days, which will be directly transplanted to soda saline-alkali land and then managed in the field. That is, if there is no effective rainfall within 2 days after transplanting, water will be replenished to the transplanting area; weed control will be implemented during the plant growth period.

[0075] Implementation effect

[0076] Statistics 60 days after transplanting showed that the survival rate of Leymus chinensis seedlings using this invention reached 85%, significantly higher than the traditional bare-root transplanting control group (survival rate 35%). The average plant height increased by approximately 50%, the number of tillers increased by approximately 2 times, and the root system exhibited a clear growth advantage under root zone protection. The results indicate that this invention has outstanding growth-promoting and rapid establishment effects in moderately saline-alkali degraded grasslands.

[0077] Example 3:

[0078] This embodiment was implemented in Haoyao Sumu, Horqin Right Wing Middle Banner, Hinggan League, Inner Mongolia Autonomous Region. This area has a temperate semi-arid continental climate with an average annual precipitation of about 350 mm and an average annual temperature of about 4.5℃. The tested soil is typical soda saline-alkali soil with a pH of 10.5-10.6, a total salt content of 0.75-1.5%, and an organic matter content of 0.3-0.8%. The surface vegetation is mainly composed of Artemisia argyi, Suaeda salsa, and Suaeda salsa, while Leymus chinensis is sparsely and fragmented, indicating a severely saline-alkali grassland.

[0079] The following is a rapid cultivation method for Leymus chinensis in moderately and severely soda-saline-alkali land using biodegradable nutrient pots:

[0080] I. Seed germination: Select salt-tolerant sheepgrass seeds, weigh 10g of seeds with a purity >80% and place them in a 500mL beaker, add 300mL of water, seal with plastic wrap and activate in a refrigerator at 4℃ for 1 week, changing the water twice during this period. After activation, transfer to a 9cm petri dish lined with moist filter paper, seal with plastic wrap, and germinate at alternating temperatures of 16℃ for 12 hours and 28℃ for 12 hours daily for 7 days. After alternating temperature germination, grow seedlings in a hydroponic system for 30 days to obtain seedlings.

[0081] II. Device preparation and substrate filling: A cylindrical micro root zone device is made of biodegradable material and filled with a non-salt-alkali substrate, with the filling volume accounting for 85-90% of the volume of the micro root zone device. Ensure that the substrate is filled evenly and fully compacted to avoid internal voids.

[0082] III. Mass cultivation of Leymus chinensis seedlings:

[0083] Select healthy seedlings and plant one seedling in each micro-root zone device. After planting, water thoroughly to help the roots establish. Cultivate for 60 days, keeping the non-saline-alkali substrate moist, until the rhizomes penetrate the wall of the micro-root zone device, the plant height is 30-60cm, and the number of tillers reaches 5-15. At this point, a device-seedling complex with rhizomes penetrating the micro-root zone device is obtained. The healthy seedlings are 4-5cm tall and have true leaves.

[0084] IV. Land leveling: For the severely saline-alkali grassland to be restored, deep loosening, shallow rotary tillage, and heavy harrowing and leveling operations are carried out in sequence to remove gravel and weeds from the plot.

[0085] V. On-site planting: The device-seedling complex with rhizomes penetrating the micro root zone obtained in step 3 is transported to the severely saline-alkali grassland to be restored. Planting is carried out in the plot treated in step 4 at a preset density of 2200 plants per acre with a plant spacing of 60cm. The holes are 15-18cm deep. After planting, the soil is covered to 1-1.5cm from the top of the micro root zone and gently compacted to ensure that the micro root zone is in close contact with the surrounding soil.

[0086] VII. Field Management: If there is no effective rainfall within 2 days after transplanting, water should be replenished to the transplanting area; weed control should be implemented during the plant growth period to ensure the establishment and growth of seedlings, thus completing the rapid establishment of Leymus chinensis in severely soda saline-alkali land in biodegradable nutrient pots.

[0087] In this embodiment, the control group will use bare-root seedlings cultivated in non-saline-alkali substrate seedling trays for 50 days, which will be directly transplanted to soda saline-alkali land and then managed in the field. That is, if there is no effective rainfall within 2 days after transplanting, water will be replenished in the transplanting area; weed control will be implemented during the plant growth period.

[0088] The micro root domain device described in step two is cylindrical with a diameter of 12cm, a height of 20cm, and a wall thickness of 8mm.

[0089] The biodegradable material described in step two is made from corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum, wherein the mass ratio of corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum is 3:2:4:1.

[0090] The non-saline-alkali substrate mentioned in step three is non-saline-alkali garden soil with a pH value of 7.0.

[0091] Implementation effect

[0092] Statistical results 60 days after transplanting showed that the survival rate of the invented group was 75%, the average plant height was 26cm, and the average number of tillers was 25; the survival rate of the control group was 32%, the average plant height was 17.2cm, and the average number of tillers was 12. This invention maintains a high survival rate and growth vigor even in severely saline-alkali environments, verifying its excellent salt and alkali tolerance and survival preservation function.

[0093] The above embodiments demonstrate that this invention, through a synergistic technical approach of "isolation and protection by a biodegradable micro-root zone device + optimization of the microenvironment using a dedicated non-salt-alkali substrate," can effectively overcome the bottleneck in Leymus chinensis establishment in degraded grasslands with varying degrees of salinity and alkalinity, significantly improving seedling survival rates and promoting plant growth and community expansion. This method is standardized, cost-effective, and environmentally friendly, offering both significant ecological and economic benefits. It can be widely applied to large-scale ecological restoration projects in saline-alkali grassland areas of northern my country, providing crucial technical support for the management of degraded grasslands.

Claims

1. A rapid cultivation method for Leymus chinensis in moderately to severely saline-alkali land based on biodegradable nutrient pots, characterized in that... The method for rapid establishment of Leymus chinensis in moderately to severely sodium-saline-alkali land based on biodegradable nutrient pots is as follows: I. Seed germination: Select salt-tolerant sheepgrass seeds, weigh 5-10g of seeds with a purity >80% and place them in a 500mL beaker, add 200-300mL of water, seal with plastic wrap and activate in a refrigerator at 4℃ for 1 week, changing the water 1-2 times during this period. After activation, transfer to a petri dish lined with moist filter paper, seal with plastic wrap, and germinate at alternating temperatures of 16℃ for 10-18 hours and 28℃ for 6-14 hours daily for 3-7 days to obtain white seeds, or after alternating temperature germination, grow in a hydroponic system for 30 days to obtain seedlings; II. Device Preparation and Matrix Filling: A cylindrical micro root zone device is made of biodegradable material and filled with a non-salt-alkali matrix. The matrix filling volume accounts for 85-90% of the volume of the micro root zone device. Ensure that the matrix is ​​filled evenly and fully compacted to avoid internal voids. III. Mass cultivation of Leymus chinensis seedlings: Method 1: Sow the white seeds obtained in step 1 directly into the substrate of the micro-root zone device. Sow 3-5 seeds in each micro-root zone device at a depth of 1-2cm. Water until the non-saline-alkali substrate is completely saturated. Then, place the device in an environment of 18-28℃ for cultivation. Keep the non-saline-alkali substrate moist during the cultivation period until the rhizomes penetrate the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will result in a device-seedling complex with rhizomes penetrating the micro-root zone device. Method 2: Select healthy seedlings with a height of 5-10cm and 2-4 true leaves. Plant one seedling in each micro-root zone device. After planting, water thoroughly and place in an environment of 18-28℃ for cultivation. During the cultivation period, keep the non-salt-alkali substrate moist until the rhizome penetrates the wall of the micro-root zone device, the plant height is >30cm and the number of tillers reaches 5-15. This will obtain the device-seedling complex with rhizome penetrating the micro-root zone device. IV. Land leveling: For the soda saline-alkali grassland to be restored, deep loosening, shallow rotary tillage, and heavy harrowing and leveling operations are carried out in sequence to remove gravel and weeds from the plot. V. On-site planting: The device-seedling complex with rhizomes penetrating the micro root zone obtained in step 3 is transported to the soda saline-alkali grassland to be restored. Plant the seedlings in holes at a preset density of 1800-2200 seedlings per acre and a spacing of 50-60cm between seedlings. The holes should be 15-18cm deep. After planting, cover the seedlings with soil up to 1-1.5cm from the top of the micro root zone and gently compact the soil to ensure that the micro root zone is in close contact with the surrounding soil. VII. Field Management: If there is no effective rainfall within 2 days after transplanting, water should be replenished to the transplanting area; weed control should be implemented during the plant growth period to ensure the establishment and growth of seedlings, thus completing the rapid establishment of Leymus chinensis in soda saline-alkali land using biodegradable nutrient pots.

2. The method for rapid establishment of Leymus chinensis in moderately to severely saline-alkali land based on biodegradable nutrient pots according to claim 1, characterized in that... The micro root domain device described in step two is cylindrical with a diameter of 8-12cm, a height of 15-20cm, and a wall thickness of 5-8mm.

3. The method for rapid establishment of Leymus chinensis in moderately to severely saline-alkali land based on biodegradable nutrient pots according to claim 1, characterized in that... The biodegradable material described in step two is made from corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum, wherein the mass ratio of corn stalks, decomposed rice husks, gelling agents, and desulfurized gypsum is 3:2:4:

1.

4. The method for rapid establishment of Leymus chinensis in moderately to severely saline-alkali land based on biodegradable nutrient pots according to claim 1, characterized in that... The non-saline-alkali substrate mentioned in step three is non-saline-alkali garden soil with a pH value of 7.0-8.

0.

5. The method for rapid establishment of Leymus chinensis in moderately to severely saline-alkali land based on biodegradable nutrient pots according to claim 1, characterized in that... The filling volume described in step two accounts for 86% of the volume of the micro root domain device.

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