Methods for controlling tobacco thistle invasion in wetlands

Abstract

The method of controlling the invasion of tobacco thistle into wetlands belongs to the field of wetland protection and management, and relates to a method of controlling the invasion of tobacco thistle into wetlands. The present invention is to solve the problem that the tobacco thistle population is showing a trend of continuous spread, resulting in a decrease in the aboveground biomass of Sesamum indica. The method is as follows: 1. Delimiting the scope; 2. Preparing a solution; 3. Injecting a solution; 4. Cleaning the plants; 5. Water management; 6. Investigation and observation. The present invention is the first to discover the important feature that the stems of tobacco thistles that invade wetlands are hollow, which fully complies with the objective laws such as the hollow stems of tobacco thistles, the acidic soil of natural wetlands, and the plants' own production of oxalic acid, and is scientific; by injecting an appropriate amount of oxalic acid solution, cleaning up dead plants, and appropriate water management, the growth and renewal of tobacco thistles are successfully inhibited; the present invention is easy to operate, not only can control the invasion of tobacco thistles, but also can promote the recovery of natural vegetation, and is suitable for large-scale promotion and application.

Description

Technical Field

[0001] The invention belongs to the field of wetland protection and management, and relates to a method for controlling tobacco thistles from invading wetlands. Background Art

[0002] Invasive plants suppress or crowd out native plants, gradually forming a single dominant population, endangering the native ecological environment, leading to the loss of biodiversity, and ultimately causing economic, social and ecological losses. Invasive plants are usually characterized by strong adaptability and competitiveness, a wide ecological range, high efficiency in reproducing offspring, high resource utilization, and a lack of natural enemies and competitors. Invasive species usually refer to naturalized species among alien species. However, in recent years, some native plants around the world have also shown invasive characteristics due to changes in environmental conditions, posing a serious threat to natural ecosystems.

[0003] Cirsium pendulum is a perennial herb belonging to the genus Cirsium of the Asteraceae family. The plant grows tall, up to 1 to 3 meters, with clustered, upright stems and thorns all over the body; the stem leaves are 4 to 16 cm long and 1.5 to 6 cm wide; the head inflorescence is drooping. Sanjiang Nature Reserve is located in the northeast of Heilongjiang Province. It is a nature reserve with swamp wetlands as the main protection object. The wetland can well represent the basic characteristics of wetlands in the biogeographic region where it is located, and is representative, typical and rare. However, affected by human activities such as farmland reclamation, the natural wetlands in the area have begun to be affected by the invasion of alien species and native plants. The survey found that Cirsium pendulum appeared in many natural wetlands in Sanjiang Nature Reserve, covering a variety of vegetation types such as the Deyeuxia purpurea community, the Carex meyeriana community, and the Carex lasiocarpa community. Taking the community of large-leafed seal as an example, the average height of the tobacco thistle is 1.1 meters, and the coverage is 40% to 100%, resulting in a 30% to 90% decrease in the aboveground biomass of the large-leafed seal. The tobacco thistle can reproduce by seeds and vegetatively. It is expected that under the influence of environmental changes, the tobacco thistle population will continue to spread, posing a serious threat to the natural vegetation of the Sanjiang wetland. However, there are currently no reports on the prevention and control technology of this plant, which restricts the scientific management of wetland vegetation. A new technology to prevent the growth and reproduction of tobacco thistle is urgently needed. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problem that the tobacco thistle population shows a trend of continuous spread, resulting in a decrease in the aboveground biomass of the large-leaved seal, and to provide a method for controlling the tobacco thistle from invading wetlands.

[0005] Ways to control the invasion of thistle into wetlands include:

[0006] 1. Delineation of scope: For natural wetlands, determine the areas most seriously affected by tobacco thistle through investigation, interviews and field surveys;

[0007] 2. Prepare the solution: weigh analytically pure oxalic acid solid and prepare an oxalic acid solution with a concentration of 0.001-0.1 mol / L using distilled water;

[0008] 3. Injection of solution: Starting from late April, regularly observe the growth of tobacco thistle in the plot determined in step 1; when the base diameter of the thickest stem of tobacco thistle reaches more than 0.2 cm and before flowering and fruiting, inject the oxalic acid solution obtained in step 2; when injecting the oxalic acid solution, the needle tip is inserted at the base of the stem, the needle tip is tilted downward and the angle between the needle tip and the stem is less than or equal to 60 degrees, and the liquid is injected into the hollow stem;

[0009] 4. Clean up the plants: 1-5 days after step 3, cut the dead tobacco thistle plants to the ground level and remove them from the wetland;

[0010] 5. Water management: After implementing step 4, irrigate immediately to keep the surface water depth above 0.1cm;

[0011] 6. Investigation and observation: Conduct a sample survey on the wetlands after the implementation of step 5, record the number of newly emerged tobacco thistle plants, and record the growth of other plants.

[0012] Advantages of the present invention:

[0013] 1. The present invention is the first to discover the important feature that the stems of the tobacco thistle that invades the wetland are hollow. This fully complies with the objective laws such as the hollow stems of the tobacco thistle, the acidic nature of the natural wetland soil, and the plant's own production of oxalic acid, and is scientific;

[0014] 2. By injecting an appropriate amount of oxalic acid solution, cleaning up dead plants, and managing water appropriately, the growth and renewal of tobacco thistles were successfully suppressed;

[0015] 3. The present invention is easy to operate, can not only control the invasion of tobacco thistle, but also promote the recovery of natural vegetation, and is suitable for large-scale promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The effect of different treatments on the number of tobacco pipe thistle plants in Example 1;

[0017] Figure 2 This is the effect of different treatments in Example 1 on the aboveground biomass of natural vegetation. DETAILED DESCRIPTION

[0018] 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.

[0019] Specific implementation method 1: The method of controlling the invasion of tobacco thistle into wetlands in this implementation method is as follows:

[0020] 1. Delineation of scope: For natural wetlands, determine the areas most seriously affected by tobacco thistle through investigation, interviews and field surveys;

[0021] 2. Prepare the solution: weigh analytically pure oxalic acid solid, prepare 0.001-0.1 mol / L oxalic acid solution with distilled water, seal the bottle mouth and store in the refrigerator;

[0022] 3. Injection of solution: Starting from late April, regularly observe the growth of tobacco thistle in the plot determined in step 1; when the base diameter of the thickest stem of tobacco thistle reaches more than 0.2 cm and before flowering and fruiting, inject the oxalic acid solution obtained in step 2; when injecting the oxalic acid solution, the needle tip is inserted at the base of the stem, the needle tip is tilted downward and the angle between the needle tip and the stem is less than or equal to 60 degrees, and the liquid is injected into the hollow stem;

[0023] 4. Clean up the plants: 1-5 days after step 3, cut the dead tobacco thistle plants to the ground level and take them away from the wetland to prevent the dead plants from affecting the growth and renewal of plants;

[0024] 5. Water management: After implementing step 4, irrigate immediately to keep the surface water depth above 0.1cm;

[0025] 6. Investigation and observation: Conduct a sample survey on the wetlands after the implementation of step 5, record the number of newly emerged tobacco thistle plants, and record the growth of other plants.

[0026] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that the concentration of the oxalic acid solution in step 2 is 0.002 mol / L. The rest is the same as specific implementation method 1.

[0027] Specific implementation method 3: This implementation method is different from specific implementation method 1 or 2 in that the concentration of the oxalic acid solution in step 2 is 0.01 mol / L. The rest is the same as specific implementation method 1 or 2.

[0028] Specific embodiment 4: This embodiment is different from specific embodiments 1 to 3 in that the concentration of the oxalic acid solution in step 2 is 0.05 mol / L. The rest is the same as specific embodiments 1 to 3.

[0029] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the injection volume of the oxalic acid solution in step 3 is preferably 100 ml, the angle between the needle and the stem is preferably 45°, and the needle tip is preferably inserted at a position 10 cm above the ground at the base of the stem. Others are the same as specific embodiments 1 to 4.

[0030] Specific implementation method 6: This implementation method is different from specific implementation methods 1 to 5 in that irrigation is performed immediately after 2 days of implementation of step 4 in step 5. The rest is the same as specific implementation methods 1 to 5.

[0031] Specific implementation method 7: This implementation method is different from specific implementation methods 1 to 6 in that step 5 maintains the surface water depth at 5 cm. The rest is the same as specific implementation methods 1 to 6.

[0032] The following examples are used to verify the effects of the present invention:

[0033] Embodiment 1:

[0034] Ways to control the invasion of thistle into wetlands include:

[0035] 1. Delineation of scope: Focusing on the natural wetland of Da Ye Zhang in Sanjiang Nature Reserve, the area seriously affected by the tobacco pipe thistle was determined through field investigation (center coordinates: E134.23595814, N48.18693315);

[0036] 2. Prepare the solution: weigh analytically pure oxalic acid solid, prepare 0.001-0.1 mol / L oxalic acid solution with distilled water, seal the bottle mouth and store in the refrigerator;

[0037] 3. Injection of solution: Starting from late April, regularly observe the growth of tobacco thistle in the plot determined in step 1; when the base diameter of the thickest stem of tobacco thistle reaches more than 0.2 cm and before flowering and fruiting, inject 100 ml of the oxalic acid solution obtained in step 2; when injecting the oxalic acid solution, the needle tip is inserted at a position 10 cm above the ground at the base of the stem, the needle tip is tilted downward at an angle of 45° with the stem, and the liquid is injected into the hollow stem;

[0038] 4. Clean up the plants: 2 days after step 3, cut the dead tobacco thistle plants to the ground level and take them away from the wetland to prevent the dead plants from affecting the growth and renewal of plants;

[0039] 5. Water management: After step 4 is implemented, irrigate immediately to keep the surface water depth within the range of 0.1-5cm;

[0040] 6. Investigation and observation: For the wetlands after the implementation of step 5, conduct a sample survey in early September to record the number of newly emerged tobacco thistle plants and the growth of other plants.

[0041] The effect of this embodiment on controlling the invasion of tobacco thistle into wetlands was verified by the following experiment: a test group and a control group were set up for testing.

[0042] Experimental group: obtained by changing the concentration of oxalic acid in step 2 of this example (0.002 mol / L, 0.01 mol / L, 0.05 mol / L, represented by C1, C2, C3 respectively) and the size of the tobacco thistle plants in step 3 (the average base diameters were 0.5 cm, 1.0 cm and 1.5 cm, respectively, and the corresponding average plant heights were 0.4 m, 0.9 m and 1.3 m respectively);

[0043] Control group: The difference from the experimental group is that distilled water was used instead of oxalic acid solution (C0) in step 2. The other treatments were the same as the experimental group. Sample plots were conducted in the experimental group and the control group. The survey indicators included the total number of tobacco thistles (number of stems) and the aboveground biomass of all other plants. The sample plot area was 1m 2 , repeat 5 times.

[0044] The test results are shown in Table 1. Figure 1 and Figure 2 :

[0045] The concentration of oxalic acid and the size of the tobacco thistle at the time of injection had a very significant effect on the control effect (P<0.001). Compared with the control (distilled water), oxalic acid can reduce the growth and reproduction of tobacco thistle ( Figure 1 ); however, as the tobacco thistle continued to grow and thicken, its resistance to external interference became stronger and stronger. When the base diameter was 1 cm, only a concentration of 0.01 mol / L could completely inhibit the renewal of tobacco thistle; and when the base diameter was 1.5 cm, only a concentration of 0.05 mol / L could completely inhibit the renewal of tobacco thistle. Overall, when the base diameter of tobacco thistle did not exceed 1.5 cm (the plant height did not exceed 1.3 m), the renewal growth of the plant in the big-leaf seal wetland could be completely controlled by injecting 0.05 mol / L of oxalic acid.

[0046] The concentration of oxalic acid and the size of the tobacco thistle at the time of injection had a very significant effect on the aboveground biomass of natural vegetation at the end of the growing season (P<0.001). Compared with the control (distilled water), the growth of the aboveground vegetation was promoted after the injection of oxalic acid to control the growth and renewal of tobacco thistle, which was manifested as a higher aboveground biomass ( Figure 2 ); however, as the injection time is continuously delayed, the growth of tobacco thistle has already inhibited other plants. This is manifested in the injection of the same concentration of oxalic acid solution. The thicker and taller the tobacco thistle is during the injection, the smaller the biomass of other plants. Therefore, when choosing oxalic acid to control tobacco thistle, it should be implemented as early as possible, so as to effectively control its growth and reproduction while minimizing its impact on natural vegetation.

[0047] Table 1 Effects of different treatment conditions on the regeneration of tobacco thistle and the biomass of natural vegetation

[0048]

[0049]

[0050] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

Claims

1. A method for controlling the invasion of tobacco thistle into wetlands, characterized in that The method for controlling tobacco thistle invasion into wetlands is as follows:

1. Delineation of scope: For natural wetlands, determine the areas most seriously affected by tobacco thistle through investigation, interviews and field surveys; 2. Prepare the solution: weigh analytically pure oxalic acid solid and prepare an oxalic acid solution with a concentration of 0.001-0.1 mol / L using distilled water; 3. Injection of solution: Starting from late April, regularly observe the growth of tobacco thistle in the plot determined in step 1; when the base diameter of the thickest stem of tobacco thistle reaches more than 0.2 cm and before flowering and fruiting, inject the oxalic acid solution obtained in step 2; when injecting the oxalic acid solution, the needle tip is inserted at the base of the stem, the needle tip is tilted downward and the angle between the needle tip and the stem is less than or equal to 60 degrees, and the liquid is injected into the hollow stem; 4. Clean up the plants: 1-5 days after step 3, cut the dead tobacco thistle plants to the ground level and remove them from the wetland; 5. Water management: After implementing step 4, irrigate immediately to keep the surface water depth above 0.1cm; 6. Investigation and observation: Conduct a sample survey on the wetlands after the implementation of step 5, record the number of newly emerged tobacco thistle plants, and record the growth of other plants.

2. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that The concentration of the oxalic acid solution in step 2 is 0.002 mol / L.

3. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that The concentration of the oxalic acid solution in step 2 is 0.01 mol / L.

4. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that The concentration of the oxalic acid solution in step 2 is 0.05 mol / L.

5. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that In step 3, the injection volume of the oxalic acid solution is preferably 100 ml, the angle between the needle and the stem is preferably 45°, and the needle tip is inserted at a position 10 cm above the ground at the base of the stem.

6. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that In step 5, irrigate immediately 2 days after step 4 is implemented.

7. The method for controlling the invasion of tobacco thistle into wetlands according to claim 1, characterized in that Step 5: Maintain the surface water depth at 5 cm.

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