Method for restoring productivity of plants in semi-arid region

Abstract

The invention discloses a method for restoring plant productivity in a semi-arid region, relates to the technical field of ecological restoration, and aims to solve the problem of poor plant productivity restoration effect caused by uneven rainfall in the existing semi-arid region. The method comprises the following steps: 1, selecting a vegetation degradation land in a semi-arid region as a target recovery sample land, and investigating vegetation; 2, dividing the target restoration sample plot into a plurality of independent restoration units, and digging potential pools in the independent restoration units to form concave terrains; 3, by taking a vegetation survey result as a reference, dividing the vegetation into a xerophyte vegetation zone, a hygrophyte vegetation zone and an emergent vegetation zone from top to bottom according to the gradient in an equal-width manner, and carrying out vegetation configuration; 4, transplanting dominant vegetation, and supplying a water source according to the suitable growth water level of the configured plants. According to the method, micro-landform transformation and vegetation configuration are fused, a composite habitat is created through micro-landform transformation, the growth requirements of different plants are met, breeding can be conducted through seeds and rhizomes after the plants are colonized, and the micro-landform transformation is beneficial to seed interception, seed bank compensation and plant productivity recovery.

Description

Technical Field

[0001] The invention relates to the technical field of ecological restoration, and in particular to a method for restoring plant productivity in semi-arid areas. Background Art

[0002] The stability of plant productivity is the basis for maintaining the functions of terrestrial ecosystems. Due to the low precipitation and uneven seasonal distribution in semi-arid areas, drought events occur frequently and the ecosystem is fragile. At the same time, human activities interfere with and destroy the natural environment (such as grazing), leading to regional plant degradation and a sharp decline in productivity. Take the western Songnen Plain as an example. In the late 1950s, the area was rich in water and grass, dense in vegetation, and more than 80% of the area was grassland and wetlands. Salinization was mainly mild salinization, and the area was only 1.08 million hectares. By 2000, due to the impact of grazing and human activities, the salinization area in the western Songnen Plain reached 2.57 million hectares, with serious plant degradation and serious loss of productivity.

[0003] The restoration of plant productivity in semi-arid areas has received increasing attention. At present, the main ways to restore plant productivity in semi-arid areas include seed replenishment and plant propagule transplantation. Among them, the seed replenishment method is simple to operate, but the seed germination rate is low in the soil of semi-arid areas, and the plant propagule transplantation method has a higher effect on plant restoration than the seed replenishment method. However, the uneven distribution of precipitation in semi-arid areas and frequent droughts lead to a mismatch between precipitation and plant growth needs, poor restoration effects, and difficulty in achieving a coordinated improvement in production capacity and diversity. Therefore, it is urgent to optimize plant productivity restoration methods based on the climatic characteristics of semi-arid areas and improve their stability and adaptability to the environment. Summary of the invention

[0004] The present invention aims to solve the problem that uneven precipitation in existing semi-arid areas leads to poor recovery of plant productivity, and provides a method for recovering plant productivity in semi-arid areas.

[0005] The method for restoring plant productivity in semi-arid areas of the present invention comprises the following steps:

[0006] Step 1: Select vegetation degraded areas in semi-arid areas as target restoration plots, conduct vegetation surveys on the target restoration plots in summer, and investigate dominant vegetation and its suitable habitats;

[0007] Step 2: In March of the second year, the target restoration plot was divided into several independent restoration units. A concave terrain was formed by digging a potential pool in the independent restoration unit. The specific parameters were: the center depth of the concave terrain was 0.9-1.1 meters, and the gentle slope was 3-5° extending to the surrounding areas. A 30-50 cm deep ditch was dug every 1 m in the shallow pool to construct a gully network.

[0008] Step 3: Based on the vegetation survey results of step 1, divide the slope into xerophytic vegetation zone, hygrophytic vegetation zone and emergent vegetation zone with equal width from top to bottom for vegetation configuration;

[0009] Step 4: Transplant dominant vegetation in mid-May of the second year, and replenish water sources from June to August according to the suitable growth water level of the plants.

[0010] Furthermore, the vegetation coverage of the semi-arid vegetation degraded land in step 1 is less than 20%.

[0011] Furthermore, the survey objects in step one include emergent plants, hygrophytes and xerophytes.

[0012] Furthermore, the survey method in step one adopts the sample line method, with each sample line being 20 meters long and 5 equally spaced 1m×1m sample plots being set up, and the dominant vegetation is determined based on the sample plot survey results.

[0013] Furthermore, the area of ​​each independent repair unit in step 2 is 500-600m 2 .

[0014] Furthermore, in step 3, the density of emergent plants is 5-10 plants / m 2 , 20-30 wet plants / m 2 , 30-50 xerophytes / m 2 .

[0015] Beneficial effects of the present invention:

[0016] The method of the present invention fully considers the climatic characteristics of semi-arid areas and integrates micro-topography transformation with vegetation configuration. The micro-topography transformation creates a complex habitat to meet the growth needs of different plants. After the plants are colonized, they can reproduce through seeds and rhizomes. In addition, the micro-topography transformation helps to retain seeds, compensate for the seed bank, and promote the recovery of plant productivity.

[0017] The method of the present invention is highly feasible and easy to operate. The rich plant provenance and plant propagules also increase the suitability for the semi-arid environment. The habitat has high elasticity and can continuously maintain relatively high productivity of plants without subsequent management investment. It has broad application prospects in ecological restoration projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of micro-topography transformation in Example 1;

[0019] Figure 2 The following are photos of the construction process of micro-topography transformation in Example 1;

[0020] Figure 3 This is a schematic diagram of vegetation configuration in Example 1;

[0021] Figure 4 It is a top view comparing the effects of the independent repair units A and B in Example 1; wherein A is the repair effect of the independent repair unit A; and B is the repair effect of the independent repair unit B;

[0022] Figure 5 This is a statistical chart of changes in plant productivity of independent restoration units A and B in Example 1. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is not limited to the specific implementation modes listed below, but also includes any combination of the specific implementation modes.

[0024] Specific implementation method 1: The method for restoring plant productivity in semi-arid areas in this implementation method comprises the following steps:

[0025] Step 1: Select vegetation degraded areas in semi-arid areas as target restoration plots, conduct vegetation surveys on the target restoration plots in summer, and investigate dominant vegetation and its suitable habitats;

[0026] Step 2: In March of the second year, the target restoration plot was divided into several independent restoration units. A concave terrain was formed by digging a potential pool in the independent restoration unit. The specific parameters were: the center depth of the concave terrain was 0.9-1.1 meters, and the gentle slope was 3-5° extending to the surrounding areas. A 30-50 cm deep ditch was dug every 1 m in the shallow pool to construct a gully network.

[0027] Step 3: Based on the vegetation survey results of step 1, divide the slope into xerophytic vegetation zone, hygrophytic vegetation zone and emergent vegetation zone with equal width from top to bottom for vegetation configuration;

[0028] Step 4: Transplant dominant vegetation in mid-May of the second year, and replenish water sources from June to August according to the suitable growth water level of the plants.

[0029] This embodiment discloses a method for restoring plant productivity in semi-arid areas. First, the plant resources in the target restoration area are investigated; then, according to the micro-topographic undulation characteristics of the area to be restored, it is divided into several independent restoration units, and a potential pool is dug in the restoration unit to form a concave terrain; with the results of the local plant survey as a reference, the vegetation is configured according to the slope from top to bottom, divided into xerophytic vegetation belts, hygrophytic vegetation belts and emergent vegetation belts; and finally, plant cultivation and maintenance. This embodiment fully considers the climatic characteristics of semi-arid areas, and the constructed composite habitat and plant configuration can effectively maintain plant productivity. The technical feasibility of this embodiment is strong, and it has broad application prospects in ecological restoration projects.

[0030] Specific implementation method 2: In step 1 of this implementation method, the vegetation coverage of the semi-arid vegetation degraded land is less than 20%. Other steps and parameters are the same as those in the specific implementation method 1.

[0031] Specific implementation method 3: In step 1 of this implementation method, the survey objects include emergent plants, hygrophytes and xerophytes. Other steps and parameters are the same as those of specific implementation method 1 or 2.

[0032] Specific implementation method 4: In step 1 of this implementation method, the survey method adopts the sample line method, each sample line is 20 meters, and 5 equidistant 1m×1m sample plots are set, and the dominant vegetation is determined according to the sample plot survey results. Other steps and parameters are the same as those of specific implementation methods 1 to 3.

[0033] Specific implementation method 5: In step 2 of this implementation method, the area of ​​each independent repair unit is 500-600m 2 The other steps and parameters are the same as those in Specific Embodiments 1 to 4.

[0034] Specific implementation method 6: In step 3 of this implementation method, the density of emergent plants is 5-10 plants / m 2 , 20-30 wet plants / m 2 , 30-50 xerophytes / m 2 The other steps and parameters are the same as those in Specific Implementations 1 to 5.

[0035] The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation schemes and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0036] Embodiment 1:

[0037] The method for restoring plant productivity in semi-arid areas of this embodiment comprises the following steps:

[0038] Step 1: Select the semi-arid area - Tong'an Village, Da'an City, Baicheng, western Jilin, and the saline-alkali land with vegetation degradation as the target restoration plot, and conduct vegetation surveys of the target restoration plots in 2021. Use the transect method to survey regional plant resources, with each transect being 20 meters long, and set up 5 equally spaced 1m×1m plots, and determine the dominant species based on the plot survey results.

[0039] The results showed that the emergent plants in the area were mainly calamus, with a suitable water level of 50-100cm; the wet plants were mainly reeds, with a suitable water level of 0-50cm; the xerophytes were mainly alkaligrass, and the soil moisture content for alkaligrass growth was 15-20%. The coverage of xerophytes was <20%, and the wet and emergent plants only grew in nearby ditches, with a single plant diversity.

[0040] Step 2: In March 2022, according to the micro-geomorphological transformation diagram (such as Figure 1 ), to carry out micro-topography transformation, the construction process photos are as follows Figure 2First, the target restoration site was surveyed to determine the micro-geomorphological characteristics of the target restoration area. Two independent restoration units A and B were selected, each with an area of ​​500m 2 , dig a potential pool in the independent restoration unit A to form a concave terrain. Specific parameters: the center depth of the concave terrain is about 1 meter, and the gentle slope is 3-5° extending to the surrounding areas. Dig 50cm deep trenches every 1m in the shallow pool to build a gully network. Figure 1 The ellipse in the figure is the boundary of the concave terrain, and the curve on the right represents 50 cm deep trenches dug at intervals of 1 meter, which are combined to form a gully network; independent restoration unit B is the control treatment, and only gully network construction is carried out, that is, 50 cm deep trenches are dug at intervals of 1 meter in independent restoration unit B.

[0041] Step 3: Based on the vegetation survey results in step 1, the concave terrain is divided into xerophytic vegetation zone, hygrophytic vegetation zone and emergent vegetation zone with equal width from top to bottom according to the slope of the concave terrain for vegetation configuration. The xerophytic vegetation zone is planted with alkaligrana, the hygrophytic vegetation zone is planted with reed, and the emergent vegetation zone is planted with calamus. The schematic diagram of the vegetation configuration plan is shown in the figure below. Figure 3 shown.

[0042] In mid-May 2022, transplanting of target plant seedlings / propagules and sowing of seeds will be carried out, and the density of calamus in independent restoration unit A is 5 plants / m 2 , the reed density is 20 plants / m 2 ; Puccinellia tenuifolia was sown at a density of 30 seeds / m 2 In the independent restoration unit B, only Puccinellia sinensis seeds were sown at a density of 30 seeds / m 2 .

[0043] From June to August 2022, further water management will be carried out on the propagules or seeds of calamus, reed and alkaligrana in independent restoration units A and B, and the water depth of the emergent vegetation belt will be regulated and controlled at 60 cm based on the results of field surveys. The xerophytic vegetation belt will be covered with straw curtains to retain water and prevent wind and improve the seed germination rate. When all the alkaligrana seeds have germinated, the straw curtains will be piled into ridges to prevent wind and will be removed in August.

[0044] In September 2024, the effect of plant restoration will be monitored, such as Figure 4 As shown; it can be seen that according to the method of the present invention, after two years, the plant coverage in the independent restoration unit A area reaches more than 90%, while the plant coverage in the independent restoration unit B which only adopts the gully network and seed replenishment restoration method is only 10%-20%.

[0045] In September 2024, the plant productivity of the independent restoration unit A and the independent restoration unit B area was measured simultaneously, such as Figure 5After being treated according to the method of the present invention, the biomass of the independent restoration unit A reached 560g per square meter, and the biomass of the independent restoration unit B was 72g per square meter. The method of the present invention can significantly improve plant productivity and help restore plant productivity in degraded land in semi-arid areas.

Claims

1. A method for restoring plant productivity in semi-arid areas, characterized in that: The method comprises the following steps: Step 1: Select vegetation degraded areas in semi-arid areas as target restoration plots, conduct vegetation surveys on the target restoration plots in summer, and investigate dominant vegetation and its suitable habitats; Step 2: In March of the second year, the target restoration plot was divided into several independent restoration units. A concave terrain was formed by digging a potential pool in the independent restoration unit. The specific parameters were: the center depth of the concave terrain was 0.9-1.1 meters, and the gentle slope was 3-5° extending to the surrounding areas. A 30-50 cm deep ditch was dug every 1 m in the shallow pool to construct a gully network. Step 3: Based on the vegetation survey results of step 1, divide the slope into xerophytic vegetation zone, hygrophytic vegetation zone and emergent vegetation zone with equal width from top to bottom for vegetation configuration; Step 4: Transplant dominant vegetation in mid-May of the second year, and replenish water sources from June to August according to the suitable growth water level of the plants.

2. A method for restoring plant productivity in semi-arid areas according to claim 1, characterized in that: The vegetation coverage of the semi-arid vegetation-degraded land in step 1 is less than 20%.

3. A method for restoring plant productivity in semi-arid areas according to claim 1 or 2, characterized in that: The survey objects in step one include emergent plants, hygrophytes and xerophytes.

4. A method for restoring plant productivity in semi-arid areas according to claim 3, characterized in that: The survey method in step one adopts the sample line method. Each sample line is 20 meters long, and 5 equidistant 1m×1m sample plots are set up. The dominant vegetation is determined based on the sample plot survey results.

5. A method for restoring plant productivity in semi-arid areas according to claim 4, characterized in that: The area of ​​each independent repair unit in step 2 is 500-600m 2 .

6. A method for restoring plant productivity in semi-arid areas according to claim 5, characterized in that: In step 3, the density of emergent plants is 5-10 plants / m 2 , 20-30 wet plants / m 2 , 30-50 xerophytes / m 2 .

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