Grass checkered sand barrier with seed bank and planting method and application of grass checkered sand barrier

Abstract

The invention provides a grass checkered sand barrier with a seed bank and a planting method and application of the grass checkered sand barrier, and belongs to the technical field of environmental governance. The planting method of the grass checkered sand-protecting barrier comprises the following steps: mixing and weaving the overground part of a drought-resistant and barren-resistant grass shrub perennial plant, a xerophyte cuttage plant branch and rice straw straws into a grass-protecting barrier, and planting the grass checkered sand-protecting barrier; the drought-tolerant and barren-tolerant grass shrub perennial plants are selected from at least two of ladywood, lespedeza floriflora, lespedeza tenuifolia and leymus chinensis at the upper part of a mowing field in a fruit maturation period; the xerophyte cutting plant is selected from one or more of yellow willow, salix psammophila and tamarix chinensis. In the grass checkered sand barrier, the rice straw plays a role in protection, the cutting branches have a cutting survival function, seeds carried by perennial plants can germinate and grow plants in good time under the shielding of the grass checkered sand barrier, vegetation in sand or desert areas can be recovered, the vegetation coverage and density are improved, and the survival rate of the perennial plants is increased. The vegetation coverage can be improved by more than 30% compared with that of an exposed plot after planting for 2 years.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmental governance, and particularly relates to a straw checkerboard sand barrier carrying a seed bank, and a construction method and application thereof. Background Art

[0002] As a typical measure of mechanical sand fixation, straw checkerboard sand barriers are widely used in desertification control projects. Traditional straw checkerboard sand barriers usually use plant straw materials such as wheat straw, rice straw or reed. The straw is vertically inserted into the sand layer by manual or mechanical means to form a grid-like structure. Its core function is to reduce the surface wind speed, fix drifting sand and intercept dust. However, the existing technology has the following significant defects:

[0003] I. It has only a single sand fixation function. Traditional straw checkerboard sand barriers only play a role in physical sand fixation, and the materials themselves do not have biological activity. When the sand barrier materials gradually degrade, the sandy area still lacks effective vegetation cover and cannot form a sustainable ecological barrier, and additional manpower and material resources are required for replanting.

[0004] II. It relies on manual secondary operations. Vegetation reconstruction needs to carry out sowing or transplanting procedures separately after the sand barrier is laid. There are problems such as seeds being easily migrated by strong winds, eaten by animals and the degradation cycle of the sand barrier not matching, resulting in low vegetation establishment efficiency.

[0005] III. The seed survival environment is harsh. Seeds sown bare are difficult to obtain effective protection in the arid, high-temperature and strong evaporation desert environment. Especially in the initial stage of seedling root development, there is a lack of physical support from the sand fixation matrix, and the roots are extremely easy to be exposed and die due to the flow of sand grains. In addition, traditional straw checkerboards cannot provide local microenvironment improvement for seed germination, exacerbating the inhibitory effect of water stress on plant growth.

[0006] IV. The ecological restoration period is extremely long. Statistical data shows that in the treatment area using conventional straw checkerboards combined with artificial sowing, it takes 3 - 5 years to form a stable vegetation community, and 2 - 3 replanting and maintenance operations are required during this period, significantly increasing the comprehensive cost of desertification control.

[0007] Although current research has tried to combine materials such as water retention agents and adhesives with straw checkerboards, the functional integration of sand fixation materials and plant propagules has still not been achieved. Therefore, developing a straw checkerboard sand barrier with both immediate sand fixation efficiency and autonomous vegetation restoration ability has become a technical problem to be solved urgently. Summary of the Invention

[0008] In view of this, the purpose of the present invention is to provide a straw checkerboard sand barrier carrying a seed bank, and a construction method and application thereof. On the one hand, it can block drifting sand by physical methods, and on the other hand, it can take into account the restoration of sandy land vegetation and improve the local ecological benefits.

[0009] To achieve the above-mentioned invention object, the present invention provides the following technical solutions:

[0010] A method for establishing a straw checkerboard sand barrier with a seed bank, comprising the following steps: Mixing the above-ground parts of drought-tolerant and barren-tolerant perennial herbaceous shrubs, branches of drought-tolerant cuttings, and cereal straws to weave a sand barrier and establish a straw checkerboard sand barrier; The above-ground parts of the drought-tolerant and barren-tolerant perennial herbaceous shrubs are cut at the fruit ripening stage, and are selected from at least two of Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides, and Leymus chinensis; The drought-tolerant cuttings are selected from one or more of Salix gordejevii, Salix psammophila, and Tamarix chinensis.

[0011] Preferably, the above-ground parts of the drought-tolerant and barren-tolerant perennial herbaceous shrubs are cut at 50%-70% fruit ripening.

[0012] Preferably, the weaving ratio of the sand barrier is: 35-45 wt% of the above-ground parts of drought-tolerant and barren-tolerant perennial herbaceous shrubs, 15-25 wt% of branches of drought-tolerant cuttings, and 35-45 wt% of cereal straws.

[0013] More preferably, the weaving ratio of the sand barrier is: 15-25 wt% of Salix gordejevii branches, 35-45 wt% of cereal straws, 5-20 wt% of Hedysarum laeve, 5-20 wt% of Lespedeza floribunda, 5-20 wt% of Lespedeza hedysaroides, and 5-20 wt% of Leymus chinensis.

[0014] Preferably, the length of the sand barrier is 40-60 m, and the width is 40-60 cm.

[0015] More preferably, the sand barrier is woven with a degradable rope.

[0016] Preferably, the sand barrier is buried 25-35 cm deep, and 15-25 cm of stubble is left on the ground surface to make a straw checkerboard sand barrier.

[0017] Preferably, the straw checkerboard sand barriers are criss-crossed, and the specification is 40-60 cm × 40-60 cm.

[0018] The present invention also provides a straw checkerboard sand barrier produced by the above-mentioned establishment method.

[0019] The present invention also provides the application of the above-mentioned establishment method and straw checkerboard sand barrier in wind prevention and sand fixation.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] Traditional grass grid sand barriers only have a single sand fixation function. After the material is degraded, the sand area still lacks vegetation coverage and needs to be replanted. However, the present invention mixes drought-resistant and barren-resistant grass shrub perennial plants carrying seeds with branches of drought-tolerant cuttings and cereal straw to weave into grass barriers, thus constructing a progressive ecological restoration system of "early physical sand fixation-mid-term living protection-long-term vegetation restoration". In the early stage, cereal straw plays a physical role in sand fixation. Its staggered weaving structure can reduce surface wind speed and create a stable microenvironment for seed germination. In the process of degradation, it releases elements such as potassium and silicon, which improves the water holding rate of sand, neutralizes the alkalinity of sand, and promotes the colonization of rhizobia of leguminous plants. After the branches of xerophytic cuttings survive, a network consolidation layer is formed in the middle stage of cereal straw degradation, which increases surface coverage and inhibits wind erosion. The seeds carried by drought- and barren-resistant grass and shrub perennials germinate in time, and after growing into plants, they form a three-dimensional sand fixation structure, which increases the shear strength of the sand layer and realizes the simultaneous sand fixation and vegetation restoration.

[0022] In the prior art, vegetation reconstruction requires additional sowing or transplanting after the sand barrier is laid. There are problems such as seeds being easily moved by strong winds, being eaten by animals, and not matching the degradation cycle of the sand barrier, resulting in low vegetation construction efficiency. When constructing grass grid sand barriers, the present invention integrates plants carrying seeds into them. Under the shielding and protection of the grass grid sand barriers, the seeds can exist stably and germinate in time, reducing the adverse effects of external factors on the seeds and greatly improving the efficiency of vegetation construction. Two years after construction, the vegetation coverage can be increased by more than 30% compared to the bare plots. Compared with traditional management methods, it significantly shortens the time required for vegetation to form a stable community.

[0023] The desert environment is dry, hot, and has strong evaporation. It is difficult for exposed sown seeds to obtain effective protection. The root system of seedlings is easily exposed and killed due to the flow of sand in the early stage of root development, and the traditional grass grid cannot provide local microenvironment improvement for seed germination. The grass grid sand barrier of the present invention provides a good survival environment for seeds. The cereal straw can not only reduce the wind speed, but also increase the water holding rate of the sand during the degradation process, neutralize the alkalinity, and create suitable conditions for seed germination; the roots and plants formed after the branches of the xerophytic cuttings survive further stabilize the sand layer, reduce the flow of sand, and provide physical support for the growth of seedlings, effectively reducing the risk of seedlings dying due to the flow of sand, and improving the germination rate of seeds and the survival rate of seedlings.

[0024] It takes 3-5 years for a conventional grass grid combined with artificial sowing to form a stable vegetation community in the control area, during which 2-3 replanting and maintenance are required, and the overall cost is high. The grass grid sand barrier and its construction method of the present invention realize the integration of sand fixation and vegetation restoration, improve the efficiency of vegetation construction, reduce the number of replanting and maintenance, greatly reduce the overall cost of desertification control, and have good economic and ecological benefits. DETAILED DESCRIPTION

[0025] The present invention provides a method for establishing a straw checkerboard sand barrier with a seed bank, comprising the following steps: Mixing the above-ground parts of drought-tolerant and barren-tolerant perennial herbaceous shrubs, the branches of drought-tolerant cuttings, and cereal straws to weave a sand barrier and establish a straw checkerboard sand barrier.

[0026] In the present invention, the above-ground parts of drought-tolerant and barren-tolerant perennial herbaceous shrubs are cut during the fruit ripening period, and are selected from at least two of Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides, and Leymus chinensis; preferably cut when 50%-70% of the fruits of the drought-tolerant and barren-tolerant perennial herbaceous shrubs are ripe, more preferably cut when 55%-65% of the fruits are ripe, and even more preferably cut when 60% of the fruits are ripe. At this time, the seeds of the drought-tolerant and barren-tolerant perennial herbaceous shrubs (Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides, and Leymus chinensis) are sufficient in quantity and have high seed vigor and are easy to germinate; in addition, about 40% of the unripe fruits are reserved for subsequent natural dissemination to maintain the dynamic balance of the sand seed bank.

[0027] In the present invention, the drought-tolerant cuttings are selected from one or more of Salix gordejevii, Salix psammophila, and Tamarix chinensis. The branches of Salix gordejevii, Salix psammophila, and Tamarix chinensis have the ability to survive cuttings, and are characterized by drought tolerance and high cutting survival rate. The cereal straws degrade slowly over time, and the roots of the cuttings of Salix gordejevii, Salix psammophila, and Tamarix chinensis that have survived cutting can form a reticular consolidation layer and increase the surface coverage, replacing the cereal straws to continue to inhibit wind erosion.

[0028] In the present invention, preferably, the cereal straws are selected from one or more of rice straws, wheat straws, oat straws, and millet straws.

[0029] The straw checkerboard sand barrier of the present invention constructs a progressive ecological restoration system of "physical sand fixation in the early stage - living body protection in the middle stage - long-term vegetation restoration" through the multi-level compatibility of cereal straw, branches of drought-tolerant cuttage plants, and drought-tolerant and barren-tolerant grass and shrub perennial plants (seed carrier plants). Specifically, cereal straw has a high cellulose content and a dense silicified epidermis, and it degrades slowly after being laid. Its interlaced weaving structure can reduce the surface wind speed and create a stable microenvironment for seed germination. In addition, cereal straw is rich in elements such as potassium and silicon, which are gradually released into the sand layer during the degradation process, improving the water retention rate of the sandy land, neutralizing the alkalinity of the sand, and promoting the colonization of rhizobia in leguminous plants such as Hedysarum laeve. Branches of Salix gordejevii, Salix psammophila, and Tamarix chinensis have the ability to survive by cuttage and can enter the rapid growth stage in the middle stage of the degradation of cereal straw. Their fibrous roots form a reticular consolidation layer within a depth of 30 cm, increasing the surface coverage and replacing the cereal straw to continue to inhibit wind erosion. Seeds carried by drought-tolerant and barren-tolerant grass and shrub perennial plants can germinate and survive to form strong plants. Among them, the main root of Hedysarum laeve reaches 2 - 3 m deep to achieve deep sand fixation, and the lateral roots of Lespedeza hedysaroides extend horizontally by 1 - 1.5 m to form a shallow network, forming a three-dimensional sand fixation structure with the roots of drought-tolerant cuttage plants, increasing the shear strength of the sand layer. In addition, leguminous Hedysarum laeve, Lespedeza floribunda, and Lespedeza hedysaroides input nitrogen into the soil through biological nitrogen fixation every year, promoting the tillering of Leymus chinensis of the Gramineae family; while the dense fibrous roots of Leymus chinensis can improve the water retention capacity of the sand layer and in turn improve the survival rate of Salix gordejevii branches in the dry season.

[0030] In the present invention, the preferred weaving ratio of the sand barrier is 35 - 45 wt% of the above-ground part of drought-tolerant and barren-tolerant grass and shrub perennial plants, 15 - 25 wt% of branches of drought-tolerant cuttage plants, and 35 - 45 wt% of cereal straw; further preferably, it is 15 - 25 wt% of Salix gordejevii branches, 35 - 45 wt% of cereal straw, 5 - 20 wt% of Hedysarum laeve, 5 - 20 wt% of Lespedeza floribunda, 5 - 20 wt% of Lespedeza hedysaroides, and 5 - 20 wt% of Leymus chinensis; more preferably, it is 20 wt% of Salix gordejevii branches, 40 wt% of cereal straw, 10 wt% of Hedysarum laeve, 10 wt% of Lespedeza floribunda, 10 wt% of Lespedeza hedysaroides, and 10 wt% of Leymus chinensis to better exert the above ecological restoration functions.

[0031] In the present invention, the preferred length of the sand barrier is 40 - 60 m, further preferably 45 - 55 m, and more preferably 50 m; the preferred width of the sand barrier is 40 - 60 cm, further preferably 45 - 55 cm, and more preferably 50 cm.

[0032] In the present invention, it is preferred that the sand barrier is woven with a degradable rope. Further preferably, the degradable rope is selected from degradable ropes made of jute, sisal, PLA (polylactic acid), PBAT (polybutylene adipate terephthalate), and their composite materials. Using a degradable rope to weave the sand barrier can not only ensure the stability of the sand barrier weaving but also avoid environmental pollution caused by traditional plastic ropes.

[0033] In the present invention, when constructing the straw checkerboard sand barriers, it is preferred that the buried depth of the barriers is 25 - 35 cm and the stubble left on the ground surface is 15 - 25 cm; more preferably, the buried depth is 28 - 32 cm and the stubble left on the ground surface is 18 - 22 cm; most preferably, the buried depth is 30 cm and the stubble left on the ground surface is 20 cm.

[0034] In the present invention, it is preferred that the completed straw checkerboard sand barriers are crisscrossed with a specification of 40 - 60 cm × 40 - 60 cm, and more preferably 50 cm × 50 cm.

[0035] The present invention also provides the straw checkerboard sand barriers constructed by the above construction method and their applications in wind prevention and sand fixation.

[0036] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0037] Example 1

[0038] A construction method of a straw checkerboard sand barrier with a seed bank is as follows:

[0039] (1) When 60% of the fruits of Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides and Leymus chinensis are mature, cut the above-ground parts.

[0040] (2) Mix 20 wt% of yellow willow branches, 40 wt% of millet straw, 10 wt% of Hedysarum laeve, 10 wt% of Lespedeza floribunda, 10 wt% of Lespedeza hedysaroides and 10 wt% of Leymus chinensis by mass, and weave them into a sand barrier with a length of 50 m and a width of 50 cm using hemp ropes.

[0041] (3) Bury the sand barrier in the sand, with a buried depth of 30 cm and a stubble of 20 cm left on the ground surface, and distribute it in a crisscross pattern to form a straw checkerboard sand barrier with a specification of 50 cm × 50 cm.

[0042] Example 2

[0043] A construction method of a straw checkerboard sand barrier with a seed bank is as follows:

[0044] (1) When 50% of the fruits of Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides and Leymus chinensis are mature, cut the above-ground parts.

[0045] (2) Mix 25 wt% of yellow willow branches, 35 wt% of millet straw, 15 wt% of Hedysarum laeve, 15 wt% of Lespedeza floribunda, 5 wt% of Lespedeza hedysaroides and 5 wt% of Leymus chinensis by mass, and weave them into a sand barrier with a length of 40 m and a width of 40 cm using hemp ropes.

[0046] (3) Bury the sand barrier in the sand, with a buried depth of 25 cm and a stubble of 15 cm left on the ground surface, and distribute it in a crisscross pattern to form a straw checkerboard sand barrier with a specification of 40 cm × 40 cm.

[0047] Example 3

[0048] A method for constructing a straw checkerboard sand barrier carrying a seed bank is as follows:

[0049] (1) When 70% of the fruits of Hedysarum laeve, Lespedeza floribunda, Lespedeza hedysaroides, and Leymus chinensis are mature, cut the above-ground parts;

[0050] (2) Mix 15 wt% of Salix gordejevii branches, 45 wt% of millet straw, 5 wt% of Hedysarum laeve, 5 wt% of Lespedeza floribunda, 15 wt% of Lespedeza hedysaroides, and 15 wt% of Leymus chinensis by mass, and weave them into a sand barrier with a PLA degradable rope. The length is 60 m and the width is 60 cm;

[0051] (3) Bury the sand barrier in the sand, with a burial depth of 35 cm and a stubble of 25 cm left on the ground surface. Distribute them in a staggered vertical and horizontal pattern to form a straw checkerboard sand barrier with a specification of 60 cm × 60 cm.

[0052] Using the spring sand burial treatment of the straw checkerboard sand barrier in Examples 1 - 3 of the present invention, the number of surviving Salix gordejevii plants per square meter in the same year was counted as 3 - 5 plants, the emergence of Hedysarum laeve seeds was 5 - 6 plants, the emergence of Lespedeza floribunda was 5 - 6 plants, the number of Lespedeza hedysaroides plants was 4 - 5 plants, and the number of Leymus chinensis plants was 2 - 3 plants. On the one hand, the straw checkerboard sand barrier constructed by the present invention can block drifting sand by physical methods, and on the other hand, it can take into account the restoration of sandy land vegetation and improve the local ecological benefits.

[0053] In addition, in August of the establishment year, the second year, and the third year of Example 1 respectively, the straw checkerboard sand barrier treated with a specification of length × width of 50 cm × 50 cm in the restored sandy land was used as the observed quadrat area for vegetation coverage observation, and repeated 5 times. The observation results are shown in Table 1.

[0054] Table 1 Observation results of vegetation coverage of straw checkerboard sand barriers in different establishment years

[0055]

[0056] It can be seen from Table 1 that in August of the same year, when the straw checkerboard sand barrier of the present invention was used to construct on the bare sandy land, the vegetation coverage per unit area (per square meter) reached an average of more than 20% after construction, mainly with the survival of Salix gordejevii. In the second year after construction, the vegetation coverage increased by more than 30% compared with the bare plot. In the third year after construction, the vegetation coverage increased by more than 40% compared with the bare plot.

[0057] Example 4

[0058] A method for constructing a straw checkerboard sand barrier carrying a seed bank, which is different from Example 1 in that:

[0059] Mix 20 wt% of Salix psammophila branches, 40 wt% of millet straw, 20 wt% of Hedysarum laeve, and 20 wt% of Lespedeza floribunda by mass fraction, and braid them into a straw barrier with hemp ropes.

[0060] Example 5

[0061] A method for constructing a straw checkerboard sand barrier with a seed bank is different from Example 1 in that:

[0062] Mix 15 wt% of Tamarix chinensis branches, 35 wt% of millet straw, 15 wt% of Hedysarum laeve, 15 wt% of Lespedeza hedysaroides var. subsericea, and 20 wt% of Leymus chinensis by mass fraction, and braid them into a straw barrier with hemp ropes.

[0063] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for constructing a grass grid sand barrier with a seed bank, characterized in that: The following steps are involved: The aboveground parts of drought-resistant and barren-resistant grass and shrub perennial plants, branches of xerophytic cuttings and cereal straw are mixed and woven into a grass barrier to build a grass grid sand barrier; the aboveground parts of the drought-resistant and barren-resistant grass and shrub perennial plants are mowed during the fruit ripening period and are selected from at least two of the group consisting of Elaeagnus scabra, Lespedeza multiflora, Lespedeza tenuifolia and Leymus chinensis; the xerophytic cuttings are selected from one or more of the group consisting of Salix yellowifolia, Salix psammophila and Tamarix chinensis.

2. The method of planting according to claim 1, characterized in that: The aboveground parts of the drought-tolerant and barren-tolerant grass shrub perennial plants are cut when 50% to 70% of the fruits are ripe.

3. The implantation method according to claim 1, characterized in that: The weaving ratio of the grass barrier is: 35-45wt% of the aboveground parts of drought-resistant and barren-resistant grass shrub perennial plants, 15-25wt% of drought-tolerant cutting plant branches, and 35-45wt% of cereal straw.

4. The implantation method according to claim 1 or 3, characterized in that: The weaving ratio of the grass barrier is: 15-25wt% of Salix yellowifolia branches, 35-45wt% of cereal straw, 5-20wt% of Folium strychnifolium, 5-20wt% of Lespedeza multiflora, 5-20wt% of Lespedeza tenuifolia and 5-20wt% of Leymus chinensis.

5. The implantation method according to claim 1, characterized in that: The length of the grass barrier is 40-60m and the width is 40-60cm.

6. The implantation method according to claim 1 or 5, characterized in that: The grass barrier is woven using degradable ropes.

7. The implantation method according to claim 1, characterized in that: The grass barrier is buried at a depth of 25-35 cm, and a grass grid sand barrier is built with 15-25 cm of stubble on the ground surface.

8. The implantation method according to claim 1, characterized in that: The grass grid sand barrier is crisscrossed and has a specification of 40-60cm×40-60cm.

9. The grass grid sand barrier constructed by the construction method according to any one of claims 1 to 8.

10. Use of the planting method described in any one of claims 1 to 8 or the straw grid sand barrier described in claim 9 in windbreak and sand fixation.

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