CN114651552B - Quick recovery method for vegetation in saline-alkali soil - Google Patents

Abstract

The invention discloses a quick recovery method for vegetation in saline-alkali soil. The method comprises the following steps: uniformly mixing a soil conditioner with grass seeds, sowing the mixture in saline-alkali soil, wrapping the grass seeds in the soil conditioner after sowing, and realizing quick recovery of vegetation in the saline-alkali soil through growth and development; the soil conditioner comprises the following components in parts by weight: 25 to 35 parts of gypsum, 8 to 10 parts of aluminum sulfate, 2 to 4 parts of sulfur powder, 0.6 to 0.8 part of polyacrylamide, 0.1 to 0.3 part of microbial agent and 50 to 60 parts of organic material. According to the invention, the grass seeds are wrapped in the soil conditioner and simultaneously applied in a stripe manner, so that the cost can be reduced, the physical isolation is formed between the grass seeds and the saline-alkali soil in the germination period of the grass seeds, the saline-alkali stress can be reduced, the applied soil conditioner can provide nutrients for plant growth while reducing the saline-alkali obstacle of the soil, and the emergence rate and the survival rate of the grass seeds are improved, so that the vegetation in the saline-alkali soil can be quickly recovered.

Description

Rapid recovery method of vegetation in saline-alkali land

technical field

The invention relates to the field of restoration of saline-alkali grassland vegetation, in particular to a rapid restoration method for saline-alkali land vegetation.

Background technique

Affected by soil salinization, grassland plant biodiversity declines, ecosystem stability, productivity and carrying capacity decline, pasture yield and coverage decrease; soil nutrient loss, fertility decline, soil structure deteriorates, and grassland ecosystems are fragile. Grassland salinization not only affects the regional ecological environment, but also has a significant impact on the development of animal husbandry.

At present, salinized grassland vegetation restoration technology mainly includes biological restoration technology, physical restoration technology and chemical restoration technology. Bioremediation technology mainly refers to the succession of the grassland plant community to the top community through artificial intervention or natural succession, thereby forming a complex community structure and function, increasing species diversity, and improving the resistance of the grassland ecosystem. There are two ways to plant saline-alkali-tolerant plants for vegetation reconstruction and native plant restoration. Physical remediation measures are mainly to restore saline-alkali soil by improving the physical structure of the soil, increasing soil permeability and porosity, promoting soil salt leaching, and reducing salt surface accumulation. Chemical remediation measures are mainly to add chemical amendments to the soil, adjust the composition of soil salinity through chemical reactions, and improve the soil structure to meet the needs of crop growth. In order to improve the vegetation recovery effect of saline-alkali land, people often physically and chemically improve the saline-alkali land first, and then plant saline-alkali-tolerant plants, but these methods have very limited effects, and the cost is relatively high, and the vegetation restoration period is long.

Contents of the invention

The purpose of the present invention is to provide a rapid recovery method for vegetation in saline-alkali land, which solves the problems of low saline-alkali tolerance in the germination and seedling stages of grass seeds and the large demand for soil improvers. The grass seeds are mixed in the soil improver without mixing with Direct contact with saline-alkali soil avoids the potential saline-alkali stress in the germination and seedling stages of grass seeds; in addition, the applied soil improver can concentrate the main components to improve the soil around the root system of grass seeds, creating a good growth environment for the root system and at the same time Can provide nutrients.

The present invention protects a method for quickly restoring vegetation in saline-alkali land, comprising the steps of:

Mix the soil conditioner and the grass seeds uniformly and sow them in the saline-alkali soil. After sowing, the grass seeds are wrapped in the soil conditioner, and the rapid recovery of saline-alkali vegetation can be realized through growth and development;

In parts by weight, the soil conditioner is composed of the following components: 25-35 parts of gypsum, 8-10 parts of aluminum sulfate, 2-4 parts of sulfur powder, 0.6-0.8 parts of polyacrylamide, 0.1 parts of microbial agent ～0.3 parts, 50～60 parts of organic materials.

Preferably, the soil conditioner is in powder form.

In parts by weight, the soil conditioner can consist of the following components:

30-35 parts of gypsum, 8-10 parts of aluminum sulfate, 3-4 parts of sulfur powder, 0.7-0.8 parts of polyacrylamide, 0.2-0.3 parts of microbial agent, 50-57 parts of organic materials.

In a first embodiment of the present invention, in parts by weight, the soil conditioner consists of the following components:

35 parts of gypsum, 8 parts of aluminum sulfate, 3 parts of sulfur powder, 0.7 parts of polyacrylamide, 0.3 parts of microbial agent, 53 parts of organic materials.

In the second embodiment of the present invention, in parts by weight, the soil conditioner consists of the following components:

35 parts of gypsum, 10 parts of aluminum sulfate, 4 parts of sulfur powder, 0.8 parts of polyacrylamide, 0.2 parts of microbial agent, 50 parts of organic materials.

In a third embodiment of the present invention, in parts by weight, the soil conditioner consists of the following components:

30 parts of gypsum, 8 parts of aluminum sulfate, 4 parts of sulfur powder, 0.7 parts of polyacrylamide, 0.3 parts of microbial agent, 57 parts of organic materials.

In the above method, the mass percentage of calcium sulfate dihydrate in the gypsum can be ≥75%, such as 89% or 85%;

The polyacrylamide can be anionic, the molecular weight can be ≤4 million (such as 3 million or 4 million), and the active substance content can be ≥90% (such as 95%);

The effective number of viable bacteria of the microbial bacterial agent can be ≥ 200 million/g;

The mass percentage of organic matter in the organic material can be ≥ 20%, such as 65%.

In the above method, the gypsum includes but not limited to desulfurized gypsum, phosphogypsum, citrate gypsum;

The microbial agent includes but not limited to Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium;

The organic materials include, but are not limited to, decomposed farmyard manure (such as decomposed sheep manure), decomposed crop straw, and activated humic acid.

In the above-mentioned method, the application amount of the soil conditioner is determined according to the degree of soil salinity;

Mild saline-alkali land: when pH<9, the application rate of the soil improver is 200-300kg/mu;

Moderate saline-alkali land: when 9<pH<10, the application rate of the soil improver is 300-400kg/mu, such as 400kg/mu;

Severe saline-alkali land: when pH>10, the application rate of the soil improver is 400-500kg/mu, such as 450kg/mu or 500kg/mu.

In the above method, the grass species can be saline-alkali tolerant perennial plants and/or halophytes;

The saline-alkali-tolerant perennial plant can be a leguminous plant and/or a gramineous plant;

The leguminous plant can be at least one of alfalfa, sweet rhinoceros and safflower;

The gramineous plant can be at least one of Leymus chinensis, Elymus chinensis and Star grass;

The halophyte can be at least one of Suaeda salsa and Suaeda falciparum.

In the above method, the sowing time may be before the rainy season (June-July) every year.

In the above method, the sowing method can be strip application, the row spacing can be 15-30cm (such as 20-30cm, 20cm or 30cm), and the soil can be covered after sowing, and the thickness can be 1-3cm (such as 1.5-2cm);

The sowing can be single sowing or mixed sowing, and the dosage of the grass seeds during single sowing can be as follows: 2 to 3 kg/mu for mild saline-alkali land, 3 to 4 kg/mu for moderate saline-alkali land, and 4 to 5 kg/mu for severe saline-alkali land; The consumption of described grass seed can be as follows: mix by 2～3 kinds of grass seeds and carry out sowing, when 2 kinds of grass seeds are mixed, the seeding amount of each grass seed is calculated according to its unicast rate 60%～70%; When three kinds of grass are mixed, the sowing amount of each grass is calculated as 40% to 50% of its single sowing amount.

Further, the method may further include the following steps before the sowing: first, deep plow the saline-alkali land to a depth of 25-30 cm, then harrow the ground so that the diameter of the soil particles is less than or equal to 3 cm, and finally level the soil with a height difference of ±10 cm. Optionally, the saline-alkali land is a severe saline-alkali land. After the leveling, the method also includes irrigation and salt washing. The flood irrigation method is adopted, and the irrigation volume is 60-200 square meters per mu. After soaking for 1-3 days, all the remaining water on the surface drain out.

Further, the method may further include the following steps after the sowing: about one month after the emergence of the grass seed (such as mid-July), applying the chemical fertilizer strips to the soil in the middle of the two rows of plants, fertilizing The thickness of the back cover soil is 2-5cm (such as 2-3cm), the distance from the root system of the plant is 7-15cm (such as 8-10cm), and the application of pure nitrogen is 8-15kg/mu (such as 8kg/mu, 9kg/mu).

The present invention has following beneficial effects:

(1) In the present invention, the grass seeds are wrapped in the soil improver and the cost can be reduced at the same time, and the physical isolation between the grass seed germination period and the saline-alkali soil can reduce the saline-alkali stress, and the applied soil improver can reduce the soil saline-alkali barrier At the same time, it can also provide nutrients for plant growth, improve the emergence rate and survival rate of grass species, so as to realize the rapid recovery of vegetation in saline-alkali land.

(2) The method of the present invention can reduce soil pH, alkalization degree and sodium adsorption ratio of saline-alkali land plots, increase organic matter content, and increase fresh grass output.

Detailed ways

The present invention will be further described in detail below in conjunction with specific embodiments, and the given examples are only for clarifying the present invention, not for limiting the scope of the present invention. The examples provided below can be used as a guideline for those skilled in the art to make further improvements, and are not intended to limit the present invention in any way.

The experimental methods used in the following examples are conventional methods unless otherwise specified.

Example 1

The Songnen Plain is heavily saline-alkali land. The soil in the 0-20cm soil layer was collected in Shuzi Village, Yuzi Township, Qian'an County, Songyuan City, Jilin Province, and brought back to the laboratory for soil box simulation tests. The average pH value of the tested soil is 10.2, and the total salt content is 1.2g/kg, which is a severe soda alkaline soil.

Fill the above-mentioned test soil with a thickness of 25 cm in the self-made soil box, divide it into two, and set them as the test group and the control group respectively, and each treatment is repeated 3 times. Among them, the test group opened a V-shaped planting ditch with a depth of 8 cm and a top width of 15 cm in the middle of the soil box. A mixture of grass seeds and soil conditioner was applied in the ditch, and then covered with soil to a depth of 1 cm. The tested weeds were a mixture of Cynas chinensis, Saltawan, Elymus salsa and Suaeda salsa, 80 grains each. The soil improver is configured according to the following mass ratios: 35 parts of desulfurized gypsum, 8 parts of aluminum sulfate, 3 parts of sulfur powder, 0.7 parts of polyacrylamide, 0.3 parts of microbial agent, 53 parts of organic fertilizer, and the application amount is equivalent to 450kg/ mu.

Among them, the content of calcium sulfate dihydrate in desulfurized gypsum is 89%, purchased from Guodian Jilin Baicheng Longhua Thermal Power Plant; polyacrylamide is anionic, with a molecular weight of 4 million, and an effective substance content of 95%, purchased from Shandong Chenda Chemical Co., Ltd.; The microbial agent is Bacillus subtilis, the number of effective viable bacteria is ≥200 million/g, purchased from Inner Mongolia Jinwoyuan Fertilizer Co., Ltd.; the organic matter content of activated humic acid is 65%, purchased from Inner Mongolia Mengyue Biotechnology Co., Ltd.

The control group was operated in the same way as the test group except that no soil amendment was applied.

Immediately after sowing, irrigation is carried out, and the amount of irrigation water is equivalent to 80 cubic meters per mu in the field. After that, water is replenished every 5 days, and the amount of water replenishment is 10 cubic meters per mu. The test lasted for 30 days, during which water was replenished 5 times, and the total irrigation amount was equivalent to 130 m3/mu in the field. The temperature in the laboratory was kept above 20°C, and the peak emergence period was 4-15 days after sowing, and the emergence rate of various grass species was counted on the 20th day, and the results are shown in Table 1.

Grass seed emergence rate in table 1, embodiment 1

Note: Different letters behind the numbers in the same column indicate a significant difference (P<0.05).

As can be seen from Table 1, the method of the present invention is used to restore vegetation in saline-alkali land, and the emergence rate of Selma, Salsa, Elymus and Suaeda salsa can be significantly improved. Compared with the control group, the seedling emergence rates of Sinna, Saltawan, Elymus salsa and Suaeda salsa in the test group increased by 35, 41, 49 and 47 percentage points respectively, and the average emergence rates of the four grass species were higher than 43 percent.

Example 2

Moderate and severe saline-alkali land in Songnen Plain. The test site is located in Suizi Village, Yuzi Township, Qian'an County, Songyuan City, Jilin Province, and the time is from May 2020 to September 2020. The total area of the test site is 1365 mu, the pH value of the 0-20cm soil is 9.1-10.3, the total salt content is 1.8-12.7g/kg, the alkalization degree is 22.8-90.6%, the soil Na ⁺ , CO ₃ ^2- and HCO ₃ ^- The ion content is high, which is a typical soda saline-alkali soil. The basic soil nutrient content is relatively low, the organic matter content is 3.7-7.2g/kg, the total nitrogen content is 0.4-1.1g/kg, the available phosphorus content is 0.5-5.4g/kg, and the available potassium content is 83.4-159.7mg/kg .

Due to the uneven distribution of salinity in the test site, spatial interpolation analysis was carried out according to the pH value of the collected basic soil samples, and the test site was divided into two different levels: moderate (9<pH<10) and severe (pH>10). area of salinity. Each area is further divided into a control plot and a test plot, wherein the control plot adopts the traditional method, and the test plot adopts the method of the present invention.

In this embodiment, the moderate saline-alkali land area is 826 mu, of which 50 mu is the control plot and 776 mu is the test plot. The area of severe saline-alkali land is 539 mu, of which 50 mu is the control plot and 489 mu is the experimental plot.

S1. Leveling the land: All plots are first plowed with a conventional plow to a depth of 25-30cm. Then, use a disc harrow to crush the soil, the diameter of the soil particles is ≤3cm, and the ground is flat after harrowing, with a height difference of ±10cm.

S2. Preparation of soil improver: Weigh 35 parts of desulfurized gypsum, 10 parts of aluminum sulfate, 4 parts of sulfur powder, 0.8 parts of polyacrylamide, 0.2 parts of microbial agent, and 50 parts of humic acid. After fully mixing with a mixer, configure Powdered soil conditioner.

Among them, the content of calcium sulfate dihydrate in desulfurized gypsum is 89%, purchased from Guodian Jilin Baicheng Longhua Thermal Power Plant; polyacrylamide is anionic, with a molecular weight of 4 million, and an effective substance content of 95%, purchased from Shandong Chenda Chemical Co., Ltd.; The microbial agent is Bacillus subtilis, the number of effective viable bacteria is ≥200 million/g, purchased from Inner Mongolia Jinwoyuan Fertilizer Co., Ltd.; the organic matter content of activated humic acid is 65%, purchased from Inner Mongolia Mengyue Biotechnology Co., Ltd.

S3. Determine the amount of soil improver: in moderate saline-alkali land, the amount of the above-mentioned improver is 400kg/mu. In severe saline-alkali land, the application rate of the above-mentioned improver is 500kg/mu.

S4. Selection of grass species: in moderate saline-alkali land, choose Elymus, clover and Suaeda salsa for mixed sowing. The seeding rate of each grass species is 1.5kg/mu, and the total seeding rate is 4.5kg/mu; in severe saline-alkali land, choose The seeding rate of Stargrass, Sinensis and Suaeda falciparum is mixed, the seeding rate of each grass species is 2kg/mu, and the total seeding rate is 6kg/mu.

S5. Sowing: Sowing on June 1-5, the operation method is as follows:

Test plot: Before sowing, use a mixer to mix the soil amendments required for different salinity levels with the grass seeds evenly to form a mixture. That is: mix 400kg of soil improver and 4.5kg of grass seeds per mu of moderate saline-alkali land, and mix evenly of 500kg of soil improver and 6kg of grass seeds for severe saline-alkali land. Thereafter, use a seeder to drill the above-mentioned mixture in the leveled land with a row spacing of 20 cm and a soil covering thickness of 1.5 to 2 cm.

Control plot: Before sowing, use a spreader to evenly spread the required soil amendment on the soil surface, use a rotary tiller to mix it evenly with the surface 0-15cm soil, and then sow grass seeds in strips, the row spacing and soil depth are the same as The test plots are the same.

S6. Fertilization: From July 15 to 17, 2020, use a fertilization machine to apply compound fertilizer strips to the soil in the middle of the two rows of plants. After fertilization, the thickness of the covering soil is 2 to 3 cm, and the distance from the plant root system is 8 to 10 cm. The compound fertilizer is purchased from the local agricultural materials market, the ratio of nitrogen, phosphorus and potassium is 30:10:11, and the amount of fertilizer applied is 30kg/mu, which is equivalent to 9kg/mu of pure nitrogen.

S7. Grass harvesting: Harvest from September 7 to 10. When harvesting, select 5 representative 1m×1m quadrats in the test plot and the control plot respectively, and measure the yield of fresh grass. At the same time, the five-point sampling method was used to collect 5 mixed soil samples in the pasture growth row, and the sampling depth was 0-20 cm, and the soil salinity index and organic matter content were measured. The results are shown in Table 2.

Table 2, embodiment 2 soil salinity index, organic matter content and fresh grass output

Note: Different letters behind the numbers in the same column indicate a significant difference (P<0.05).

As can be seen from Table 2, adopting the method of the present invention to restore vegetation in saline-alkali land has achieved remarkable results in the first year. In moderately saline-alkali plots, compared with the control plots, the pH of the 0-20cm soil in the experimental plots decreased by 0.7 units, the degree of alkalization decreased by 21.1 percentage points, the content of organic matter increased by 43.1%, and the yield of fresh grass increased by 76.2% %, but there was no significant difference in salt content. In the severe saline-alkali land, compared with the control land, the soil pH of 0-20cm in the experimental land decreased by 0.6 units, the degree of alkalization decreased by 35.6 percentage points, the organic matter content increased by 34.8%, and the fresh grass yield increased by 133.3% .

Example 3

Severe saline-alkali land in Hetao irrigation area. The test site is located in Wansheng Yingzi Village, Wang Aizhao Town, Dalate Banner, Ordos City, Inner Mongolia Autonomous Region, and the time is from May to September 2021. The total area of the test area is 30 mu. The average pH value of the 0-20cm soil is 9.11, the salt content is 14.6g/kg, and the sodium adsorption ratio is 41.6. The basic soil nutrient content is relatively low, the organic matter content is 7.4g/kg, the ammonium nitrogen content is 14.2mg/kg, the nitrate nitrogen content is 17.7mg/kg, the available phosphorus content is 10.3mg/kg, and the available potassium content is 169.4 mg/kg.

Before the test started, the test area was divided into 6 fields, each with an area of about 5 mu, and ridges were built around it. Set up the experimental area and the control area, each area includes 3 fields. Wherein, the test area adopts the method of the present invention, and the control area adopts the traditional method. The operation method is as follows:

S1. Leveling the land: All plots are first plowed with a conventional plow to a depth of 25-30cm. Then, use a disc harrow to crush the soil, the diameter of the soil particles is ≤3cm, and the ground is flat after harrowing, with a height difference of ±8cm. Then irrigate and wash the salt, adopt the flood irrigation method, and the irrigation volume is 180 m3/mu. After soaking for 2 days, all the remaining water on the surface is drained.

S2. Preparation of soil improver: Weigh 30 parts of desulfurized gypsum, 8 parts of aluminum sulfate, 4 parts of sulfur powder, 0.7 parts of polyacrylamide, 0.3 parts of microbial agent, and 57 parts of organic fertilizer. Powdered soil conditioner.

Among them, the content of calcium sulfate dihydrate in desulfurized gypsum is 85%, purchased from Inner Mongolia Datang International Tuoketuo Power Generation Co., Ltd.; polyacrylamide is anionic, with a molecular weight of 3 million, and the content of effective substances is 95%, purchased from Shandong Chenda Chemical Co., Ltd.; the microbial agent is Bacillus subtilis, the number of effective viable bacteria is ≥ 200 million/g, purchased from Inner Mongolia Jinwoyuan Fertilizer Co., Ltd.; the organic matter content of sheep manure is 65%, purchased from Inner Mongolia Shepherd Organic Fertilizer Production LLC.

S3. Determine the amount of soil improver: the amount of the above-mentioned improver is 350kg/mu.

S4. Grass species selection: Elymus and Echinacea were selected for mixed sowing. The sowing rate of each grass species was 1.8kg/mu, and the total sowing rate was 3.6kg/mu.

S5. Sowing: Sowing on May 28, the operation method is as follows:

Test plot: Before sowing, use a mixer to mix the soil amendments required for different salinity levels with the grass seeds evenly to form a mixture. That is: mix 350kg of soil conditioner with 3.6kg of grass seeds evenly. Thereafter, use a seeder to drill the above-mentioned mixture in the leveled land with a row spacing of 30 cm and a soil covering thickness of 1.5 to 2 cm.

Control plot: Before sowing, use a spreader to evenly spread the required soil amendment on the soil surface, use a rotary tiller to mix it evenly with the surface layer of 0-15cm soil, and then drill the mixed grass seeds, row spacing and The soil depth was the same as that of the test plot.

S6. Fertilization: On July 12, 2021, use a fertilization machine to apply a strip of compound fertilizer to the soil in the middle of the two rows of plants. After fertilization, the thickness of the covering soil is 2-3 cm, and the distance from the plant root system is 8-10 cm. The compound fertilizer is purchased from the local agricultural materials market, the ratio of nitrogen, phosphorus and potassium content is 20:10:15, and the amount of fertilizer applied is 40kg/mu, which is equivalent to 8kg/mu of pure nitrogen.

S7. Grass harvesting: Harvest on September 2. During harvesting, select a representative 1m×1m quadrat in each plot of the test plot and the control plot to measure the fresh grass yield. At the same time, the five-point sampling method was used to collect mixed soil samples in the pasture growth row. One soil sample was collected for each plot, and the sampling depth was 0-20 cm. The soil salinity index and organic matter content were measured. The results are shown in Table 3.

Table 3, embodiment 3 soil salinity index, organic matter content and fresh grass output

Note: Different letters behind the numbers in the same column indicate a significant difference (P<0.05).

As can be seen from Table 3, adopting the method of the present invention to restore vegetation in saline-alkali land has achieved remarkable results in the first year. Compared with the control plot, the pH of the 0-20cm soil in the experimental plot decreased by 0.4 units, the sodium adsorption ratio decreased by 28.4%, the organic matter content increased by 22.8%, and the fresh grass yield increased by 81.8%, but the total salt content was not significant difference.

The present invention has been described in detail above. For those skilled in the art, without departing from the spirit and scope of the present invention, and without unnecessary experiments, the present invention can be practiced in a wider range under equivalent parameters, concentrations and conditions. While specific embodiments of the invention have been shown, it should be understood that the invention can be further modified. In a word, according to the principles of the present invention, this application intends to include any changes, uses or improvements to the present invention, including changes made by using conventional techniques known in the art and departing from the disclosed scope of this application. Applications of some of the essential features are possible within the scope of the appended claims.

Claims (8)

1. a saline-alkali land vegetation quick restoration method, comprises the steps: Mix the soil improver and the grass seeds evenly and sow them in saline-alkali soil. After sowing, the grass seeds are wrapped in the soil improver, and the rapid recovery of saline-alkali vegetation can be realized through growth and development; In parts by weight, the soil improver is composed of the following components: 25-35 parts of gypsum, 8-10 parts of aluminum sulfate, 2-4 parts of sulfur powder, 0.6-0.8 parts of polyacrylamide, 0.1 parts of microbial inoculum ~0.3 parts, 50~60 parts of organic materials; The mass percentage of calcium sulfate dihydrate in the gypsum is more than or equal to 75%; The polyacrylamide is anionic, with a molecular weight of ≤4 million and an active substance content of ≥90%; The effective number of viable bacteria of the microbial inoculum is more than or equal to 200 million/g; The mass percentage of organic matter in the organic material is ≥ 20%; The gypsum is desulfurized gypsum, phosphogypsum or citrate gypsum; The microbial bacterial agent is Bacillus subtilis, Bacillus licheniformis or Bacillus megaterium; The organic material is decomposed farmyard manure, decomposed crop straw or activated humic acid. 2. The method according to claim 1, characterized in that: the soil conditioner is in powder form. 3. according to the method described in any one in claim 1-2, it is characterized in that: the application amount of described soil conditioner is determined according to soil salinity degree; Mild saline-alkali land: when pH<9, the application rate of the soil improver is 200-300kg/mu; Moderate saline-alkali land: when 9<pH<10, the application rate of the soil improver is 300-400kg/mu; Severe saline-alkali land: when pH>10, the application rate of the soil improver is 400-500kg/mu. 4. according to the method described in any one in claim 1-2, it is characterized in that: described grass kind is the perennial plant and/or halophyte of saline-alkali tolerance; The saline-alkali-tolerant perennial plant is a leguminous plant and/or a gramineous plant; The leguminous plant is at least one of alfalfa, sweet rhinoceros and safflower; The gramineous plant is at least one of Leymus chinensis, Elymus chinensis and Star grass; The halophyte is at least one of Suaeda salsa and Suaeda falciparum. 5. The method according to any one of claims 1-2, characterized in that: the sowing method is strip application, the row spacing is 15-30 cm, and the soil is covered after sowing with a thickness of 1-3 cm; The sowing is single sowing or mixed sowing, and the dosage of the grass seeds during single sowing is as follows: 2~3kg/mu for mild saline-alkali land, 3~4kg/mu for moderate saline-alkali land, 4~5kg/mu for severe saline-alkali land; The dosage of grass seeds is as follows: 2~3 kinds of grass are mixed and sown. When 2 kinds of grass are mixed, the sowing amount of each grass is calculated as 60%~70% of its single sowing amount; when 3 kinds of grass are sown When mixed sowing, the sowing amount of each grass seed is calculated according to 40%~50% of its single sowing amount. 6. The method according to any one of claims 1-2, characterized in that: before the sowing, the following steps are also included: first deep plowing the saline-alkali land to a depth of 25 to 30 cm, and then harrowing the ground, soil The diameter of the particles is ≤3cm, and finally it is leveled, with a height difference of ±10cm. 7. The method according to claim 6, characterized in that: the saline-alkali land is a severe saline-alkali land, and the method also includes irrigation and salt washing after the leveling, and flood irrigation is adopted, and the irrigation volume is 60-200 m3/mu. After soaking for 1-3 days, drain all the remaining water on the surface. 8. The method according to any one of claims 1-2, characterized in that: after the sowing, it also comprises the steps of applying the fertilizer strips to the two rows of plants 1 month after the emergence of the grass seeds In the middle position of the soil, the thickness of the covering soil after fertilization is 2-5cm, the distance from the root system of the plant is 7-15cm, and the application of pure nitrogen is 8-15kg/mu.