Intertidal zone ecological restoration method based on salt marsh plant planting

Abstract

The invention belongs to the technical field of ecological restoration, and relates to an intertidal zone ecological restoration method based on salt marsh plant planting. Determining positions and distribution of single plaques, a plaque concentration area and an ecological function coverage area in the planting area; the plaque concentration area comprises N single plaques and light beaches, the distance between every two adjacent single plaques is 5-15 m, the area occupied by the single plaques is not smaller than 60%, and the area of the plaque concentration area is larger than or equal to 200 m < 2 >; the ecological function coverage area comprises M plaque concentration areas and light beaches, and the area occupied by the plaque concentration areas is not less than 50%; the ecological function coverage area accounts for more than 50% of the area of the intertidal zone restoration area; salt marsh plants are planted in the single plaques; the planting density per unit area in the single patch is not less than 80 plants / m < 2 >; after planting, the growth condition of the salt marsh plants is monitored so as to evaluate the actual survival rate and the growth condition. Ecological function coverage with the maximum area is achieved with the minimum plant planting area, and consumption of materials and manpower is effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of ecological restoration, and in particular relates to an intertidal zone ecological restoration method based on salt marsh plant planting. Background Art

[0002] Intertidal wetlands are characterized by large areas, high difficulty in planting, and large environmental disturbances. Traditional intertidal salt marsh plant planting is often carried out in a uniform density. This method consumes a lot of materials and manpower, and the survival rate and coverage efficiency of salt marsh plants are low. The project is difficult to implement and ignores the natural succession process of the ecosystem and the natural distribution pattern of biodiversity, which can easily lead to insufficient stability and self-sustaining capacity of the restored ecosystem. In addition, due to the lack of in-depth understanding of the unique environmental conditions of the intertidal zone and adaptive design, it often shows vulnerability in the face of extreme climate and environmental changes, making it difficult to achieve long-term ecological restoration and protection goals.

[0003] In addition, the existing salt marsh plant planting technology has the following disadvantages: First, large-scale planting in the restoration area requires a lot of physical labor and material resources for continuous maintenance, resulting in high material and labor costs; Second, in the special environment of the intertidal zone, it is difficult to ensure the colonization and growth of plants and the survival rate is low, especially in areas with strong winds and waves, which makes the project difficult to implement; Third, excessive attention is paid to the overall vegetation coverage rate, ignoring the structure and function of the intertidal zone ecosystem itself, and the restoration is not carried out in accordance with the laws and characteristics of vegetation development, and the vegetation is easily lacking in environmental adaptability. Summary of the invention

[0004] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the objects of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the objects of the present invention is to provide an intertidal zone ecological restoration method based on salt marsh plant planting that meets one or more of the aforementioned needs.

[0005] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions: A method for intertidal zone ecological restoration based on salt marsh plant planting comprises the following steps: S1. Select the planting area based on the intertidal zone restoration area; S2. Determine the location and distribution of individual patches, patch concentration areas and ecological function coverage areas within the planting area; the area of ​​individual patches is 15 to 30 m 2 ; Plaque concentration areas include N The light beach between the individual patches and the adjacent individual patches is 5-15m, the area occupied by all the individual patches in the patch concentration area is not less than 60%, and the area of ​​the patch concentration area is ≥200m 2 , Nis a positive integer greater than 1; the ecological function coverage area includes M The area of ​​all patch concentration areas in the ecological function coverage area is not less than 50%. M is a positive integer greater than 1; the ecological function coverage area accounts for more than 50% of the intertidal zone restoration area; S3. Plant salt marsh plants in individual patches through artificial cultivation or in situ transplanting; the planting density per unit area in individual patches shall not be less than 80 plants / m 2 ; S4. Monitor the growth of salt marsh plants after planting to assess actual survival rate and growth status.

[0006] As a preferred solution, in step S3, when there are no salt marsh plants near the intertidal zone restoration area, artificially cultivated salt marsh plants are used to plant the individual patches.

[0007] As a preferred solution, the salt marsh plant is Spirulina maritima, and seedlings are used for ground seedling transplanting; Seedlings are seedlings less than one year old that germinate from the seeds of Tripterygium wilfordii through sexual reproduction. The standard is that the stem base width is ≥2.5mm and the plant height is 10-15cm. It is suitable for wave energy density ≤80J / m 2 And the single patch area with salinity ≤15‰ during the rooting and colonization period.

[0008] As a preferred solution, the seedlings are transplanted and planted using paper cup seedlings without removing them from the pots; after the seedlings germinate and grow to 5 to 10 cm, they are transplanted into 5 to 7 cm diameter containers for cup seedling cultivation, with the transplanting density controlled at 10 to 15 plants per cup, and are transplanted out after the root system has grown to fill the container.

[0009] As a preferred solution, the salt marsh plant is Tripterygium wilfordii, and bulb seedlings are used for ground seedling transplanting; The bulb seedlings are seedlings formed by asexual reproduction of the corms of the sea sedge as explants. The diameter of the explant corm is ≥5mm, and the plant height is 10-15cm. It is suitable for wave energy density ≤150J / m 2 And the salinity of the single patch area during the rooting and colonization period is ≤15‰.

[0010] As a preferred solution, the bulb seedlings are cultivated in cup seedlings, and healthy, full, fresh bulbs with a diameter of ≥5 mm are selected. The planting density is 4 to 6 bulbs per cup, and the bulbs are transplanted after the root system has grown and filled the container.

[0011] As a preferred solution, in step S3, when native salt marsh plants exist near the intertidal zone restoration area, the single patch is planted by in situ transplanting method.

[0012] As a preferred embodiment, the salt marsh plant is Spirulina marinum, and the in-situ transplanting method is: during low tide, the seedlings are lifted up with water in the native Spirulina marinum population, and the root system is retained when lifting up the seedlings; the timing for removing the seedlings is when the flooding depth is ≥5cm during low tide, the width of the seedling removal area is ≤1m, and the interval between the seedling removal areas is ≥2m.

[0013] As a preferred solution, in step S4, if the seedling loss is ≥50%, replanting is carried out; one month after planting, the transplant survival rate is checked, and if the survival rate is ≤50%, replanting is carried out.

[0014] As a preferred embodiment, the N The value ranges from 20 to 80.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (1) Compared with the traditional uniform density flat planting technology, the present invention achieves the largest ecological function coverage with the smallest plant planting area, effectively reducing the consumption of materials and manpower; after using the intertidal zone ecological restoration method of the present invention, the planting area does not exceed 30% of the total area of ​​the intertidal zone restoration area, while the ecological function coverage area accounts for 50% of the total area of ​​the target area. This optimized resource allocation significantly reduces costs; (2) The present invention can help artificially planted salt marsh plants survive better by simulating the patch distribution of natural salt marsh plants; the arrangement between the individual patches is conducive to the overall colonization of vegetation, and at the same time, the planting density within the individual patches is high, which has a certain resistance to wind and waves, thereby improving the survival rate of plants; (3) The present invention simulates the distribution of natural patches, making the vegetation more adaptable to the intertidal environment and more resistant to wind and waves; and the vegetation naturally becomes denser under the action of plant growth, and eventually can cover the entire restoration area and develop into an ecosystem that adapts to the intertidal environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the monomer patch planting of the present invention; Figure 2 It is a schematic diagram of the structure of the plaque concentration area of ​​the present invention; Figure 3 It is a structural schematic diagram of the ecological function coverage area of ​​the present invention; Figure 4 These are regular monitoring pictures of some patches in the restoration target area of ​​Example 1 of the present invention during the initial stage of planting, after growth, and during continuous growth. DETAILED DESCRIPTION

[0017] In order to more clearly illustrate the embodiments of the present invention, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other accompanying drawings and other implementation methods can be obtained based on these accompanying drawings without creative work.

[0018] The intertidal zone ecological restoration method based on salt marsh plant planting of the present invention comprises the following steps: Step 1: Design the layout plan for the restoration area; Carry out UAV multispectral mapping of intertidal zone restoration target areas to obtain topographic, hydrological and other base environmental data. If necessary, landform reconstruction projects should be carried out first; Based on the specific base environment data, appropriate planting areas are selected, and the patch layout is designed accordingly to determine the location and distribution of individual patches, patch concentration areas and ecological function coverage areas.

[0019] When selecting a suitable planting area, the present invention requires that the planting area meets the following environmental conditions: a) It is located at a position 0.8m below the average high tide level (i.e. the height is not less than H-0.8m, H is the average high tide level), the average flooding depth of the summer astronomical high tide is ≤2m, and the average flooding duration in a single day is ≤8h; b) The conditions of muddy beach, intertidal salt marsh and estuary delta in GB / T 24708 should be met, the tidal flat sediments should be stable, the vertical sedimentation in a single spring month should be within 0-10cm, and the maximum wave energy density of tidal flat hydrodynamics should be less than 250J / m 2 ; c) The average salinity in spring is ≤18‰, and the short-term salinity extreme value is ≤23‰.

[0020] When designing the patch layout, the present invention ensures that there is enough area to support plant survival, while maximizing the perimeter-to-area ratio to form more edge areas. The construction of the patch concentration area needs to consider the distance and arrangement between patches to promote biodiversity and plant growth. To this end, the design of the single patch layout should comply with the following conditions: 1) Use bulbs and other forms as seedlings and plant them in patches; 2) The area of ​​a single plaque should be ≥15m 2 The density of salt marsh plants in a single patch should be ≥80 plants / m 2 ; 3) The distance between adjacent plaques should not be greater than the diameter of a single plaque; 4) Individual patches and the light beach areas between patches constitute the patch concentration area. The area of ​​a single patch concentration area should be ≥ 200m 2; Among them, the plaque area should not be less than 60% of the area of ​​the concentrated plaque area; 5) Within the scope of multiple plaque concentration areas and the light beach areas between them, the area of ​​plaque concentration areas should not be less than 50% of the total area.

[0021] Step 2: constructing monomeric plaques and plaque concentration areas; According to the designed plan, a single patch is set up in the restoration area and the location of the single patch is marked. The single patch is the basic unit for simulating the distribution of natural salt marsh plants. The salt marsh plants required for constructing a single patch can be obtained mainly through artificial cultivation and in situ transplanting. Taking the sea sedge as an example, it is explained in detail, which is divided into two situations: The first method: If there is no native sea sedge near the restoration area, artificially cultivated sea sedge should be used to construct patches, and it is appropriate to use seedlings or bulb seedlings for ground seedling transplanting; Seedlings are seedlings less than 1 year old that are germinated by sexual reproduction of Tripterygium wilfordii seeds. The standard is that the stem base width is ≥ 2.5 mm and the plant height is 10-15 cm. It is suitable for the area selection requirements in step 1. The wave energy density is ≤ 80 J / m 2 And the salinity during the rooting and colonization period is ≤15‰; The bulb seedlings are seedlings formed by asexual reproduction of the corms of the sea sedge as explants. The standard is that the diameter of the explant corm is ≥5mm, the plant height is 10-15cm, and it is suitable for the requirements of the area selection in step 1. The wave energy density is ≤150J / m 2 And the salinity during the rooting and colonization period is ≤15‰; The cup seedling cultivation method is an auxiliary planting method that can be used to increase the success rate of sea sedge cultivation. The principle is: using paper cups that are easy for roots to penetrate and degrade as containers to cultivate sea sedge seedlings can retain a relatively complete root system and resist stronger water dynamics. Paper cup seedlings do not need to be removed from the pot for transplanting and can be planted directly. After the seedlings germinate and grow to 5-10cm, they can be transplanted into 5-7cm diameter containers for cup seedling cultivation. The transplanting density should be controlled at 10-15 plants / cup. After the root system grows and fills the container, it can be transplanted. The wave energy density that can be planted is ≤150J / m 2 , the salinity during the rooting and planting period is ≤15‰. For bulb cup seedling cultivation, healthy, full, fresh bulbs with a diameter of ≥5mm should be selected, and the planting density is 4 to 6 bulbs / cup. After the root system grows and fills the container, it can be transplanted. The wave energy density that can be planted is ≤250J / m 2 , areas where salinity is ≤18‰ during the rooting and colonization period.

[0022] The second method: If there is native sea sedge near the restoration area, the in situ transplanting method can be used. Find areas with high plant density and strong plants in the wild sea sedge population, and remove seedlings in the sea sedge patches with water at low tide. When removing seedlings, try to keep the root system to reduce root damage; the time to remove seedlings should be when the flooding depth is ≥5cm at low tide; to ensure that the area can recover quickly after removing seedlings, the width of the removal area should be ≤1m, and the interval between the removal areas should be ≥2m.

[0023] Whether it is artificial seedling raising or in-situ transplanting, the planting of patches must be carried out according to the design plan. On the basis of the individual patches, according to the markings, a patch concentration area formed by the arrangement and combination of multiple individual patches is planted to better play the edge effect between patches. The planting of patches and patch concentration areas must follow the conditions of the patch layout design in step 1 to ensure that the sea sedge population can be established and play a restoration function.

[0024] Step 4: Monitoring and maintenance work; Monitor plant growth after planting to assess actual survival rate and growth status. If the seedling loss in a single patch is ≥50%, replanting should be carried out in time and necessary auxiliary planting measures should be taken; one month after planting, the transplant survival rate should be checked, and if the plant survival rate in a single patch is ≤50%, replanting should be carried out in time. Foliar topdressing and plant hormone regulation during the growing season can effectively improve the stress resistance and growth of salt marsh plants, and help complete the colony growth faster; Coastal intertidal plants are affected by seasonal tides and extreme climates, have a relatively short growth window, and are greatly affected by pests and diseases. During the establishment of the colony, pest and disease management should be done well, and regular pesticide application and maintenance should be carried out to prevent and control the occurrence of pests and diseases. In addition, maintenance work needs to be adjusted according to the specific environmental conditions of the intertidal zone and the growth needs of the plants.

[0025] The following is a detailed description of the salt marsh plant planting of the present invention, which is specifically divided into three levels: The first level is single patch planting: Figure 1 As shown in Figure 1, the planting density per unit area in single patch 1 is generally ≥80 plants / m 2 The area of ​​a single patch 1 is generally 15 to 30 m 2 , according to the micro-topographic environment, the spacing between adjacent planted patches D It varies from 5 to 15m; The second level is the plaque concentration area composed of multiple monomeric plaques, such as Figure 2 As shown, a patch concentration area 2 can be composed of multiple individual patches 1, and the area of ​​the patch concentration area includes the area of ​​the individual patches and the area of ​​the light beach 3 between the patches, wherein the area occupied by the patches is greater than 60%, and the patch contiguous P in the patch concentration area is achieved within one to two years through natural growth; The third level is the ecological function coverage area composed of several patch concentration areas, such as Figure 3 As shown, the proportion of patch concentration area 2 within ecological function coverage area 4 is generally designed to be no less than 50% of the total tidal flat restoration area; The actual planting patch area is equivalent to 30% of the total area to ensure the survival and continuation of the salt marsh plant population in the area. Considering the survival rate, the replanting amount is generally 30-50% of the initial planting amount. In areas with large tidal erosion, bamboo strips 5 are used as tide-blocking measures on the tidal surface of the patch to reduce the adverse effects of tidal erosion on seedlings during initial planting.

[0026] Embodiment 1: The restoration target area for the intertidal zone ecological restoration method based on salt marsh plant planting in this embodiment is located in the Shanwan intertidal zone in Zhapu Town, Pinghu City, Zhejiang Province. The Shanwan sample section has a total area of ​​about 100 acres. The design scheme includes single patches, patch concentration areas and ecological function coverage areas composed of patches set up according to actual conditions. The plants used for restoration are the local pioneer salt marsh plant Tripterygium wilfordii.

[0027] First, through the hyperspectral exploration of ecological niches by drones, the basement environmental data of the target area is obtained, and the planting plan is designed with reference to the contour map.

[0028] There are 9 patch concentration areas in the ecological function coverage area in the planting plan, each of which has 28 circular patches, mainly arranged in a pattern of 3 to 6 patches per row. The circular patches are relatively close together, so that the planting area accounts for more than 30% of the total area of ​​the target area, and the ecological function coverage area accounts for more than 50% of the total area of ​​the target area.

[0029] After the planting of S. maritima patches, the target area showed a restoration process of three stages: initial planting, post-growth, and continuous growth, with a span of about 5 months. The vegetation area reached 94.44 mu, an increase of 37.44 mu compared with the initial area of ​​57 mu, which is 1.66 times the original area. The plant density reached 700-800 plants / m 2 .

[0030] like Figure 4 As shown in the regular monitoring pictures of some patches, the plants in the patches have become denser and started to expand outward. This shows that the vegetation has begun to adapt to the intertidal environment, has a stronger resistance to wind and waves, and the survival rate of the plants has been further improved. The vegetation as a whole can be naturally denser under the growth of plants. At the same time, due to the edge effect, after the patch planting is completed, the vegetation gradually spreads to the area between the patches, so that the patches are connected into pieces through the natural growth of vegetation. Under this growth trend, the vegetation will eventually cover the entire restoration area and develop into an ecosystem that adapts to the intertidal environment and is resistant to wind and waves.

[0031] The above description is only a detailed description of the preferred embodiments and principles of the present invention. For ordinary technicians in this field, according to the ideas provided by the present invention, there will be changes in the specific implementation methods, and these changes should also be regarded as the protection scope of the present invention.

Claims

1. A method for intertidal zone ecological restoration based on salt marsh plant planting, characterized in that: The following steps are involved: S1. Select planting areas based on intertidal zone restoration areas; S2. Determine the location and distribution of individual patches, patch concentration areas and ecological function coverage areas within the planting area; the area of ​​individual patches is 15 to 30 m 2 ; Plaque concentration areas include N The light beach between the individual patches and the adjacent individual patches is 5-15m, the area occupied by all the individual patches in the patch concentration area is not less than 60%, and the area of ​​the patch concentration area is ≥200m 2 , N is a positive integer greater than 1; the ecological function coverage area includes M The area of ​​all patch concentration areas in the ecological function coverage area is not less than 50%. M is a positive integer greater than 1; the ecological function coverage area accounts for more than 50% of the intertidal zone restoration area; S3. Plant salt marsh plants in individual patches through artificial cultivation or in situ transplanting; the planting density per unit area in individual patches shall not be less than 80 plants / m 2 ; S4. Monitor the growth of salt marsh plants after planting to assess actual survival rate and growth status.

2. The intertidal zone ecological restoration method according to claim 1, characterized in that: In step S3, when there are no salt marsh plants near the intertidal zone restoration area, artificially cultivated salt marsh plants are used to plant the single patch.

3. The intertidal zone ecological restoration method according to claim 2, characterized in that: The salt marsh plant is Tripterygium wilfordii, and seedlings are used for ground seedling transplanting; Seedlings are seedlings less than one year old that germinate from the seeds of Tripterygium wilfordii through sexual reproduction. The standard is that the stem base width is ≥2.5mm and the plant height is 10-15cm. It is suitable for wave energy density ≤80J / m 2 And the salinity of the single patch area during the rooting and colonization period is ≤15‰.

4. The intertidal zone ecological restoration method according to claim 3, characterized in that: The seedlings are transplanted and planted using paper cup seedlings without removing the pots; after the seedlings germinate and grow to 5-10 cm, they are transplanted into 5-7 cm diameter containers for cup seedling cultivation, with the transplanting density controlled at 10-15 plants / cup, and are transplanted after the root systems have grown to fill the containers.

5. The intertidal zone ecological restoration method according to claim 2, characterized in that: The salt marsh plant is Tripterygium wilfordii, and bulb seedlings are used for ground seedling transplanting; The bulb seedlings are seedlings formed by asexual reproduction of the corms of the sea sedge as explants. The diameter of the explant corm is ≥5mm, and the plant height is 10-15cm. It is suitable for wave energy density ≤150J / m 2 And the salinity of the single patch area during the rooting and colonization period is ≤15‰.

6. The intertidal zone ecological restoration method according to claim 5, characterized in that: The bulb seedlings are cultivated in cup seedlings, and healthy, full, fresh bulbs with a diameter of ≥5 mm are selected. The planting density is 4 to 6 bulbs per cup, and the bulbs are planted out after the root system grows and fills the container.

7. The intertidal zone ecological restoration method according to claim 1, characterized in that: In the step S3, when native salt marsh plants exist near the intertidal zone restoration area, the single patch is planted by the in situ transplanting method.

8. The intertidal zone ecological restoration method according to claim 7, characterized in that: The salt marsh plant is Spirulina maritima, and the in-situ transplanting method is: lift the seedlings with water in the native Spirulina maritima population at low tide, and retain the root system when lifting the seedlings; the timing for taking the seedlings is when the water depth is ≥5cm at low tide, the width of the seedling taking area is ≤1m, and the interval between the seedling taking areas is ≥2m.

9. The intertidal zone ecological restoration method according to any one of claims 1 to 8, characterized in that: In step S4, if the seedling loss is ≥50%, replanting is carried out; after 1 month of planting, the transplant survival rate is checked, and if the survival rate is ≤50%, replanting is carried out.

10. The intertidal zone ecological restoration method according to any one of claims 1 to 8, characterized in that: The value of N is 20-80.

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