Method for evaluating ecological restoration and carbon sequestration effect of mangrove forest in non-woodland

Abstract

The invention relates to the technical field of ecological management. The invention provides a method for ecological restoration of a mangrove forest in a non-woodland and a method for evaluating ecological restoration and carbon sequestration effects of the mangrove forest in the non-woodland based on the method. By the adoption of the ecological restoration method for the mangrove forest in the non-woodland, the problems that the survival rate of mangrove seedlings is low and soil loss is serious due to the fact that soil of a planting bed in a coast area is scoured seriously can be effectively solved, and stable plant communities can be formed in the non-woodland mangrove forest restoration; the carbon sequestration ecological function of the mangrove forest can be improved, and organic carbon accumulation of the wetland is promoted. Meanwhile, when the method is used for evaluation, the related evaluation indexes are comprehensive and complete, the evaluation result can be visually reflected in space, and the evaluation effect is higher in pertinence and accuracy.

Description

Technical Field

[0001] The present invention relates to the field of ecological management technology, and in particular to a method for ecological restoration and carbon sequestration effect evaluation of mangroves in non-forested land. Background Art

[0002] Mangroves are important ecosystems for the blue carbon sink of the ocean. Their protection and restoration have become an important means of responding to climate change in the marine sector and an important part of the "nature-based solution". Their carbon pool includes vegetation biomass and soil carbon pool. At present, there have been many research reports on the organic carbon storage in mangrove areas abroad. Some reports quantify the carbon sequestration level of mangrove areas from different spatial and temporal perspectives. For example, Donato et al. quantitatively estimated the carbon storage of the entire mangrove ecosystem in the tropics (Indo-Pacific region) by estimating the biomass of mangrove vegetation, soil carbon content and soil depth changes (Donato DC, Kauffman JB, Murdiyarso D, et al. Mangroves among the most carbon-rich forests in the tropics. Nat Geosci, 2011, 4(5): 293-297.). Lovelock et al. investigated two mangrove areas (white marina mangrove areas) planted for different lengths of time in New Zealand. By evaluating the structure, age, soil carbon content, growth, and growth-limiting factors of mangroves, they concluded that newly established mangroves have a significant function of continuous carbon deposition and nutrient accumulation (Lovelock CE, Sorrell BK, Hancock N, et al. Mangrove Forest and Soil Development on a Rapidly Accreting Shore in New Zealand. Ecosystems, 2010, 13(3): 437-451). Hien et al. estimated the soil carbon storage and burial rate of artificially planted Kandelia candel in northern Vietnam and confirmed that mangrove reforestation has a high carbon storage capacity (Hien HT, Marchand C, Aime J, et al. Belowground carbon sequestration in a mature planted mangroves (Northern Viet Nam). Forest Ecol Manag, 2018, 407: 191-199).

[0003] While protecting existing mangrove ecosystems, it's crucial to select mangrove species with high carbon density and optimal carbon sequestration environments for afforestation and stand reconstruction, expand mangrove acreage, and increase mangrove carbon storage. Few patents exist for evaluating the carbon sequestration effects of mangroves. Patent CN114766309A provides a mixed planting method for improving the carbon sequestration capacity of mangrove vegetation, but this method is not suitable for planting mangroves in unsuitable forestland and cannot improve mangrove carbon sequestration in unsuitable forestland. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for ecological restoration of mangroves in non-suitable forest land and a method for evaluating the carbon sequestration effect, so as to solve the problem that the soil in the planting beds in coastal areas is severely eroded, resulting in low survival rate of mangrove seedlings and serious soil loss, and ultimately leading to low carbon sequestration capacity of plants and soil. At the same time, it can comprehensively, spatially and intuitively reflect the evaluation results, and the evaluation effect is more targeted and accurate.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for ecological restoration of mangroves in unsuitable forestland, comprising the following steps:

[0007] (1) Protective wooden boards and pine piles are placed around the planting bed, and geotextile-filled sandbags are piled on the sea side of the pine piles;

[0008] (2) Lay bamboo baskets on the planting bed, then fill the baskets with sea mud and lay plastic black film;

[0009] (3) Dig holes on the surface of the plastic black film in step (2) and place 18-25 plants / m 2 Planting density Planting mangrove seedlings.

[0010] Preferably, the surface height of the pine wood piles is not lower than the surface height of the planting bed and is higher than the stacking height of the geotextile-filled sandbags.

[0011] Preferably, a fence is provided between the protective wooden board and the planting bed, wherein the upper portion of the fence is fixed to the top of the protective wooden board, and the lower portion of the fence is fixed to the bottom of the protective wooden board.

[0012] Preferably, the method further comprises reinforcing the bamboo basket with bamboo strips around and at the bottom or laying geotextile inside the bamboo basket; the specification of the bamboo basket in step (2) is 500cm×300cm×450cm.

[0013] Preferably, the protective wooden board is fixed to the side of the pine pile facing the planting bed.

[0014] Preferably, the height of the mangrove seedling is 30-50 cm, and the crown width of the mangrove seedling is 25-35 cm.

[0015] The present invention also provides a method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland based on the above method, comprising the following steps:

[0016] (1) Determine ecological restoration evaluation indicators and carbon sequestration effect evaluation indicators, and build an ecological restoration and carbon sequestration effectiveness evaluation indicator system;

[0017] (2) The corresponding weight values of ecological restoration assessment indicators are determined through the hierarchical analysis method, and the scores corresponding to the ecological restoration assessment indicators are assigned. Then, the ecological restoration effect level is evaluated based on the weight values and the assigned scores.

[0018] Preferably, the ecological restoration assessment indicators include plant height increment, ground diameter increment, preservation rate and canopy density, and the carbon sequestration assessment indicators include plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density and soil carbon density.

[0019] Preferably, the weight of the plant height increment is 0.2, the weight of the ground diameter increment is 0.2, the weight of the preservation rate is 0.4, and the weight of the canopy density is 0.2.

[0020] As a preferred option, the scoring standards for ecological restoration assessment indicators are as follows:

[0021]

[0022] As a preferred option, the ecological restoration effect rating standards are as follows:

[0023]

[0024] By adopting the above technical solution, the present invention has the following beneficial effects:

[0025] The technical solution of this invention, through the installation of protective wooden planks, pinewood stakes, geotextile-filled sandbags, reinforced bamboo baskets, and double-layered black plastic film, helps mangrove seedlings survive in coastal areas not suitable for forestland, reduces soil erosion, and promotes the formation of stable mangrove plant communities. Furthermore, while ensuring the ecological restoration of mangroves in unsuitable forestland, the technical solution also improves soil and plant carbon storage, significantly enhancing the ecological function of mangrove carbon sequestration.

[0026] The technical solution of the present invention constructs an indicator system for evaluating the ecological restoration and carbon sequestration effects of mangroves in non-suitable forest lands. It not only screens out important indicators such as plant height increment, ground diameter increment, preservation rate, and canopy density from the perspective of ecological restoration, but also screens out indicators for evaluating carbon sinks from the perspective of carbon sequestration (plant carbon sequestration rate, soil carbon sequestration rate, total carbon sequestration rate or plant carbon density, soil carbon density, total carbon density), forming a complete method for evaluating the ecological restoration and carbon sequestration effects of mangroves in non-suitable forest lands. The evaluation indicators involved are comprehensive and can reflect the evaluation results spatially and intuitively, making the evaluation effects more targeted and accurate. DETAILED DESCRIPTION

[0027] The present invention provides a method for ecological restoration of mangroves in unsuitable forestland, which is characterized by comprising the following steps:

[0028] (1) Protective wooden boards and pinewood piles are placed around the planting bed, and geotextile-filled sandbags are piled on the sea side of the pinewood piles;

[0029] (2) Lay bamboo baskets on the planting bed, then fill the baskets with sea mud and lay black plastic film;

[0030] (3) Dig holes on the surface of the plastic black film in step (2) and place 18-25 plants / m 2 Planting density Planting mangrove seedlings.

[0031] In the present invention, protective wooden boards and pine piles are arranged around the planting bed, in the order of the planting bed, protective wooden boards, and pine piles. The protective wooden boards are arranged on the side of the pine piles close to the planting bed to prevent seawater from eroding the soil; geotextiles filled with sandbags are piled on the sea side of the pine piles, and the stacking height is lower than the pine piles and protective wooden boards. The height of the pine pile surface is not lower than the height of the planting bed surface, and further, the height of the pine pile surface is the same as the height of the planting bed surface or slightly higher than the planting bed surface by 10 cm. In the present invention, a fence is set between the protective wooden boards and the planting bed, the upper part of the fence is fixed on the top of the protective wooden boards, and the lower part of the fence is fixed on the bottom of the protective wooden boards. The setting of the fence described in the present invention can prevent garbage from entering the mangrove planting area and affecting the growth of seedlings. In the present invention, the protective wooden boards are fixed on the side of the pine piles facing the planting bed.

[0032] In the present invention, bamboo baskets are laid on the planting bed, and the specifications of the bamboo baskets are preferably 500cm×300cm×450cm. The present invention also includes reinforcing the bamboo baskets, and the reinforcement method is preferably to use bamboo strips to reinforce the four sides and bottom of the bamboo basket or to lay a layer of geotextile or non-woven fabric on the inside of the bamboo basket. When bamboo strips are used to reinforce the four sides and bottom of the bamboo basket in the present invention, it is preferred to use bamboo strips in a "well" shape to reinforce the four sides and bottom of the bamboo basket, so that the four sides and bottom of the bamboo basket are widened by 3cm. The present invention can enhance the stability of the planting bed by closely arranging the reinforced bamboo baskets. In the present invention, sea mud is filled inside the bamboo basket and the gaps between the bamboo baskets are also filled with sea mud. After filling with sea mud, a double layer of plastic black film is laid.

[0033] In the present invention, holes are dug on the surface of the plastic black film and mangrove seedlings are planted. The mangrove seedlings of the present invention are preferably seedlings with uniform growth conditions; the planting density is preferably 18-25 plants / m 2 , further preferably 20-24 plants / m 2 During the planting process of the present invention, there is no need to remove the planting bag, so that the mangrove roots can fully adapt to the habitat of the planting bag. After planting, the gaps between the bamboo baskets are filled with sea mud.

[0034] In the present invention, the length of the pine wood pile is preferably 6-8m, and further preferably 8m; the diameter of the pine wood pile is preferably 7-10cm, and further preferably 10cm; the height of the protective wooden board is preferably 1-2m, and further preferably 2m; the width of the protective wooden board is preferably 1-2m, and further preferably 1m; the thickness of the protective wooden board is preferably 1.3cm-1.5cm, and further preferably 1.5cm.

[0035] In the present invention, the height of the mangrove seedlings is preferably 30-50 cm, more preferably 50 cm; the crown width of the mangrove seedlings is preferably 25-35 cm, more preferably 35 cm.

[0036] In the present invention, the stacking width of the geotextile sand-filled bags is preferably 2-3 m, and more preferably 3 cm; the stacking height of the geotextile sand-filled bags is preferably flush with the height of the planting bed.

[0037] The present invention also provides a method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland based on the above method, comprising the following steps:

[0038] (1) Determine ecological restoration evaluation indicators and carbon sequestration effect evaluation indicators, and build an ecological restoration and carbon sequestration effectiveness evaluation indicator system;

[0039] (2) The corresponding weight values of ecological restoration assessment indicators are determined through the hierarchical analysis method, and the scores corresponding to the ecological restoration assessment indicators are assigned. Then, the ecological restoration effect level is evaluated based on the weight values and the assigned scores.

[0040] In the present invention, the ecological restoration assessment indicators include plant height increment, ground diameter increment, preservation rate, and canopy density. The carbon sequestration effectiveness assessment indicators include plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density, and soil carbon density. In the present invention, the sum of the plant carbon sequestration rate and the soil carbon sequestration rate equals the total carbon sequestration rate, and the sum of the plant carbon density and the soil carbon density equals the total carbon density.

[0041] In the present invention, the hierarchical analysis method is used to calculate the weights of each indicator of the constructed evaluation system. The weights of each indicator for the ecological restoration evaluation of mangroves in non-suitable forestland are shown in Table 1.

[0042] In the present invention, the score pairs corresponding to the evaluation indicators of ecological restoration of mangroves in non-suitable forestland are scored, with the maximum score being 5 points and the minimum score being 1 point. The scoring basis is shown in Table 2.

[0043] In the present invention, the ecological restoration effect of mangroves is divided into evaluation grades according to the weights and scoring conditions. The grades are shown in Table 3. Specifically, when 4.5≤comprehensive score≤5, the ecological restoration effect of mangroves in non-suitable forest land is excellent; when 4≤comprehensive score<4.5, the ecological restoration effect of mangroves in non-suitable forest land is good; when 3≤comprehensive score<4, the ecological restoration effect of mangroves in non-suitable forest land is medium; when 2≤comprehensive score<3, the ecological restoration effect of mangroves in non-suitable forest land is poor; when 1≤comprehensive score<2, the ecological restoration effect of mangroves in non-suitable forest land is very poor.

[0044] Table 1 Weights of various evaluation indicators for ecological restoration of mangroves in unsuitable forestland

[0045]

[0046] Table 2 Scoring of various evaluation indicators for mangrove ecological restoration in unsuitable forestland

[0047]

[0048] Table 3 Classification of ecological restoration effects of mangroves in unsuitable forestland

[0049]

[0050] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0051] Example 1

[0052] A method for ecological restoration of mangroves in unsuitable forestland, comprising the following steps:

[0053] (1) Protective wooden boards and pine stakes are placed around the planting bed in sequence. The pine stakes are 8m long and 7-10cm in diameter and are located on the outermost side of the planting bed. The protective wooden boards are 2m high, 1m wide, and 1.5cm thick. They are fixed on the upper part of the pine stakes and on the side of the pine stakes facing the planting bed. A fence is placed between the protective wooden boards and the planting bed. The upper part of the fence is fixed on the top of the protective wooden boards, and the lower part of the fence is fixed on the bottom of the protective wooden boards. Geotextiles filled with sandbags are piled on the seaward side of the pine stakes, with the stacking height slightly lower than the pine stakes and protective wooden boards. The pile surface height is slightly higher than the planting bed surface height by 10cm.

[0054] (2) Place bamboo baskets of 500cm×300cm×450cm on the planting bed and reinforce them in a “well” shape with bamboo strips. Widen the sides and bottom of the baskets by 3cm. Arrange the baskets closely to enhance the stability of the planting bed.

[0055] (3) Fill the bamboo basket with sea mud and fill the gaps between the bamboo baskets with sea mud. After filling with sea mud, lay a double layer of black plastic film;

[0056] (4) Dig holes on the surface of the plastic black film and plant mangrove seedlings of similar specifications at a planting density of 24 plants / m 2 The height of the mangrove seedlings is 45 cm and the crown width is 30 cm. When planting, there is no need to remove the planting bag, so that the mangrove roots can fully adapt to the habitat of the planting bag.

[0057] The evaluation method for ecological restoration and carbon sequestration of mangroves in unsuitable forestland based on the above method is as follows:

[0058] (1) Four years after planting, three 2m×2m plots were set up in the area. Based on the ecological restoration evaluation indicators of plant height increment, ground diameter increment, preservation rate, and canopy density, and the carbon sequestration effect evaluation indicators of plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density, and soil carbon density, an ecological restoration and carbon sequestration effectiveness evaluation index system was constructed.

[0059] (2) The corresponding weight values of ecological restoration assessment indicators are determined by the hierarchical analysis method. The weights of each indicator are shown in Table 1. The scores corresponding to the ecological restoration assessment indicators are assigned. The scoring basis is shown in Table 2. Then, the ecological restoration effect level is evaluated based on the weight values and the assigned scores. The restoration effect level is shown in Table 3.

[0060] Example 2

[0061] A method for ecological restoration of mangroves in unsuitable forestland, comprising the following steps:

[0062] (1) Protective wooden boards and pine stakes are placed around the planting bed in sequence. The pine stakes are 6m long and 7-10cm in diameter and are located on the outermost side of the planting bed. The protective wooden boards are 1m high, 2m wide, and 1.3cm thick. They are fixed to the upper part of the pine stakes and to the side of the pine stakes facing the planting bed. A fence is placed between the protective wooden boards and the planting bed. The upper part of the fence is fixed to the top of the protective wooden boards, and the lower part of the fence is fixed to the bottom of the protective wooden boards. Geotextiles filled with sandbags are piled on the seaward side of the pine stakes, with the pile height slightly lower than the pine stakes and protective wooden boards. The pile surface height is level with the planting bed surface height.

[0063] (2) Place bamboo baskets of 500cm×300cm×450cm on the planting bed and reinforce them in a “well” shape with bamboo strips. The sides and bottom of the baskets need to be widened by 3cm. The bamboo baskets are arranged closely to enhance the stability of the planting bed.

[0064] (3) Fill the bamboo basket with sea mud and fill the gaps between the bamboo baskets with sea mud. After filling with sea mud, lay a double layer of black plastic film;

[0065] (4) Dig holes on the surface of the plastic black film and plant mangrove seedlings of similar specifications at a planting density of 20 plants / m 2 The height of the mangrove seedlings is 30 cm and the crown width is 25 cm. When planting, there is no need to remove the planting bag, so that the mangrove roots can fully adapt to the habitat of the planting bag.

[0066] The evaluation method for ecological restoration and carbon sequestration of mangroves in unsuitable forestland based on the above method is as follows:

[0067] (1) After 4 years of planting, three 2m×2m plots were set up in the area. Based on the ecological restoration evaluation indicators of plant height increment, ground diameter increment, preservation rate, and canopy density, and the carbon sequestration evaluation indicators of plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density, and soil carbon density, an ecological restoration and carbon sequestration effectiveness evaluation index system was constructed.

[0068] (2) The corresponding weight values of ecological restoration assessment indicators are determined by the hierarchical analysis method. The weights of each indicator are shown in Table 1. The scores corresponding to the ecological restoration assessment indicators are assigned. The scoring basis is shown in Table 2. Then, the ecological restoration effect level is evaluated based on the weight values and the assigned scores. The restoration effect level is shown in Table 3.

[0069] Example 3

[0070] A method for ecological restoration of mangroves in unsuitable forestland, comprising the following steps:

[0071] (1) Protective wooden boards and pine stakes are placed around the planting bed in sequence. The pine stakes are 8m long and 7-10cm in diameter and are located on the outermost side of the planting bed. The protective wooden boards are 1m high, 1m wide, and 1.5cm thick. They are fixed to the upper part of the pine stakes and to the side of the pine stakes facing the planting bed. A fence is placed between the protective wooden boards and the planting bed. The upper part of the fence is fixed to the top of the protective wooden boards, and the lower part of the fence is fixed to the bottom of the protective wooden boards. Geotextiles filled with sandbags are piled on the seaward side of the pine stakes, with the pile height slightly lower than the pine stakes and protective wooden boards. The pile surface height is slightly higher than the planting bed surface height by 10cm.

[0072] (2) Place bamboo baskets of 500cm×300cm×450cm on the planting bed and reinforce them in a “well” shape with bamboo strips. The sides and bottom of the baskets need to be widened by 3cm. The bamboo baskets are arranged closely to enhance the stability of the planting bed.

[0073] (3) Fill the bamboo basket with sea mud and fill the gaps between the bamboo baskets with sea mud. After filling with sea mud, lay a double layer of black plastic film;

[0074] (4) Dig holes on the surface of the plastic black film and plant mangrove seedlings of similar specifications at a planting density of 24 plants / m 2 The height of the mangrove seedlings is 50 cm and the crown width is 35 cm. When planting, there is no need to remove the planting bag, so that the mangrove roots can fully adapt to the habitat of the planting bag.

[0075] The evaluation method for ecological restoration and carbon sequestration of mangroves in unsuitable forestland based on the above method is as follows:

[0076] (1) Four years after planting, three 2m×2m plots were set up in the area. Based on the ecological restoration evaluation indicators of plant height increment, ground diameter increment, preservation rate, and canopy density, and the carbon sequestration evaluation indicators of plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density, and soil carbon density, an ecological restoration and carbon sequestration effectiveness evaluation index system was constructed.

[0077] (2) The corresponding weight values of ecological restoration assessment indicators are determined by the hierarchical analysis method. The weights of each indicator are shown in Table 1. The scores corresponding to the ecological restoration assessment indicators are assigned. The scoring basis is shown in Table 2. Then, the ecological restoration effect level is evaluated based on the weight values and the assigned scores. The restoration effect level is shown in Table 3.

[0078] Comparative Example 1

[0079] Same as Example 1, only the bamboo basket is replaced by hollow bricks.

[0080] The hollow bricks are formed by bonding standard prefabricated C30 concrete hollow bricks, and the bottom of the hollow bricks is not sealed.

[0081] Comparative Example 2

[0082] Same as Example 1, only the four sides and the bottom of the bamboo basket are not reinforced.

[0083] Comparative Example 3

[0084] As in Example 1, only the sea mud is replaced by backfill soil.

[0085] The backfill soil is composed of sea sand, sea mud and red soil in a mass ratio of 2:1:5.

[0086] Comparative Example 4

[0087] The same as in Example 1, except that the pinewood piles and protective wooden boards are not provided.

[0088] Test Example 1

[0089] Four years after planting, a comprehensive evaluation of the ecological restoration and carbon sequestration effects of mangroves in non-forestable land in Examples 1-3 and Comparative Examples 1-4 was conducted. Three 2m x 2m plots were set up in the area. The number of surviving plants, height, ground diameter, and canopy density were counted. Height increment, ground diameter increment, survival rate, plant carbon density, and plant carbon sequestration rate were then calculated. Soil samples were collected to measure soil organic matter, and soil organic carbon density and soil carbon sequestration rate were calculated. Finally, the total carbon density and total mangrove carbon sequestration rate were calculated.

[0090] The specific calculation formula is as follows:

[0091] Height increase = (height of the plant 4 years after planting - height of the plant at planting) / height of the plant 4 years after planting × 100

[0092] Ground diameter increment = (ground diameter of the plant 4 years after planting - ground diameter of the plant at planting) / ground diameter of the plant 4 years after planting × 100

[0093] Survival rate = (number of plants planted - number of plants surviving after 4 years) / number of plants planted × 100

[0094] Plant carbon density = existing biomass of vegetation × mangrove plant carbon content (take 45%)

[0095] Plant carbon sequestration rate = plant carbon density / planting year (4 years)

[0096] Soil carbon density = organic carbon mass fraction × soil bulk density × soil thickness

[0097] Soil organic carbon mass fraction = soil organic matter mass fraction / 1.724

[0098] Soil carbon sequestration rate = soil carbon density / planting year (4 years)

[0099] Total mangrove carbon density = plant carbon density + soil carbon density

[0100] Total carbon sequestration rate of mangroves = plant carbon sequestration rate + soil carbon sequestration rate

[0101] There are various methods for measuring mangrove biomass, including calculations based on remote sensing statistical analysis and direct biomass measurement using the standard wood method. Considering the potential harm to mangroves caused by tree felling, this paper uses an estimation method, using the relationship between aboveground biomass and tree height and diameter at breast height to estimate the biomass of Tung trees. The relationship between aboveground biomass, diameter at breast height, and tree height is calculated as follows: lgW = 1.49 + 0.465lg(D² * H), where W is the total aboveground biomass, D is the ground diameter, and H is the tree height. Because the underground biomass of mangrove plants is much smaller than the aboveground biomass during the early stages of growth, the underground biomass is negligible.

[0102] The calculation results of the ecological restoration indicators of mangroves in non-suitable forest land are shown in Table 4, the ecological restoration scoring results of mangroves in non-suitable forest land are shown in Table 5, and the calculation results of the carbon sequestration indicators of mangroves in non-suitable forest land are shown in Table 6.

[0103] Table 4 Ecological restoration indicators of mangroves in unsuitable forestland

[0104] Serial number Height increment / times Ground diameter increment / times Preservation rate (%) Canopy density Example 1 2.73±0.25a 5.29±0.37a 75.00±19.09a 1.00±0.00a Example 2 2.92±0.14a 6.16±1.67a 83.33±5.78a 1.00±0.00a Example 3 2.45±0.82ab 5.16±0.64a 77.78±4.81a 1.00±0.00a Comparative Example 1 2.47±0.06ab 4.96±0.81a 70.83±14.43a 1.00±0.00a Comparative Example 2 2.58±0.10a 4.42±0.42a 69.44±16.83a 0.98±0.03a Comparative Example 3 1.87±0.26b 5.51±1.95a 43.06±6.36b 0.633±0.029b Comparative Example 4 0.00±0.00c 0.00±0.00b 0.00±0.00c 0.00±0.00c

[0105] (Values are expressed as mean ± standard deviation. The Duncana method was used to compare the significant differences among the variables. Different letters indicate significant differences among the sample points (P < 0.05).)

[0106] As shown in Table 4, using the mangrove ecological restoration method for unsuitable forestland according to the present invention, the indicators of Examples 1-3 are significantly better than those of Comparative Example 4. This indicates that the technical measures adopted by the present invention significantly reduce the impact of wind and waves on the soil and mangrove seedlings, prevent the loss of cultivation medium, and effectively ensure the successful establishment of mangrove seedlings.

[0107] Table 5 Scoring of mangrove ecological restoration in unsuitable forestland

[0108]

[0109] As shown in Table 5, the comprehensive ecological restoration effect scores for mangroves on unsuitable forest land in Examples 1-3 of the present invention were "Excellent," while the comprehensive ecological restoration effect scores for Comparative Examples 1-2 were "Good," indicating inferior ecological restoration effects to those of Examples 1-3. The ecological restoration effects of Comparative Examples 3 and 4 were "Moderate" and "Very Poor," respectively, indicating little or no improvement in mangrove ecological restoration, and risks to the mangrove ecosystem. In summary, the comprehensive ecological restoration effect scores for Examples 1-3 were superior to those for Comparative Examples 1-4. This demonstrates that the method for ecological restoration of mangroves on unsuitable forest land of the present invention produces excellent results and has considerable promotional value.

[0110] Table 6 Carbon sequestration indicators of mangroves in unsuitable forestland

[0111]

[0112] (Values are expressed as mean ± standard deviation. The Duncana method was used to compare the significant differences among the variables. Different letters indicate significant differences among the sample points (P < 0.05).)

[0113] As shown in Table 6, the total carbon density or total carbon sequestration rate of Examples 1-3 of the present invention is significantly superior to that of Comparative Examples 1-4. Therefore, it can be seen that the methods described in Examples 1-3 of the present invention can achieve good mangrove restoration and carbon sequestration results. Total carbon density or total carbon sequestration rate can be used to evaluate the effectiveness of mangrove restoration and carbon sequestration.

[0114] In summary, it can be seen that by adopting the method for ecological restoration of mangroves in non-suitable forest land described in the present invention, not only can the problems of low survival rate of mangrove seedlings and serious soil loss caused by severe erosion of the planting bed soil be effectively solved, it is also beneficial to the formation of stable plant communities in the restoration of mangroves in non-suitable forest land, but also can improve the ecological function of mangrove carbon sequestration and promote the accumulation of organic carbon in wetlands.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for ecological restoration of mangroves in unsuitable forestland, characterized in that: The steps include: (1) Protective wooden boards and pinewood piles are placed around the planting bed, and geotextile-filled sandbags are piled on the sea side of the pinewood piles; (2) Lay bamboo baskets on the planting bed, then fill the baskets with sea mud and lay plastic black film; (3) Dig holes on the surface of the plastic black film in step (2) and place 18-25 plants / m 2 Planting density Planting mangrove seedlings; The surface height of the pine wood piles is not lower than the surface height of the planting bed and is higher than the stacking height of the geotextile-filled sandbags.

2. The method according to claim 1, characterized in that It also includes setting a fence between the protective wooden board and the planting bed, wherein the upper part of the fence is fixed to the top of the protective wooden board, and the lower part of the fence is fixed to the bottom of the protective wooden board.

3. The method according to claim 1, characterized in that It also includes using bamboo strips to reinforce the sides and bottom of the bamboo basket or laying geotextiles inside the bamboo basket; The specifications of the bamboo basket in step (2) are 500cm×300cm×450cm.

4. The method according to claim 1, wherein The protective wooden board is fixed to the side of the pine pile facing the planting bed.

5. The method according to claim 1, wherein The height of the mangrove seedling is 30-50 cm, and the crown width of the mangrove seedling is 25-35 cm.

6. A method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland based on the method according to any one of claims 1 to 5, characterized in that: The steps include: (1) Determine ecological restoration and carbon sequestration assessment indicators, and build an ecological restoration and carbon sequestration effectiveness assessment indicator system; (2) Determine the corresponding weight values of ecological restoration assessment indicators through the hierarchical analysis method, assign scores to the corresponding ecological restoration assessment indicators, and then evaluate the ecological restoration effect level based on the weight values and scores; The ecological restoration assessment indicators include plant height increment, ground diameter increment, preservation rate and canopy density, and the carbon sequestration assessment indicators include plant carbon sequestration rate, soil carbon sequestration rate, plant carbon density and soil carbon density.

7. The method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland according to claim 6, characterized in that: The weight of the plant height increment is 0.2, the weight of the ground diameter increment is 0.2, the weight of the preservation rate is 0.4, and the weight of the canopy density is 0.

2.

8. The method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland according to claim 6, characterized in that: The scoring standards for ecological restoration assessment indicators are as follows:

9. The method for evaluating the ecological restoration and carbon sequestration effect of mangroves in unsuitable forestland according to claim 6, characterized in that: The ecological restoration effect rating standards are as follows:

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