Mine repairing and greening method

Abstract

The invention discloses a mine repairing and greening method. The method comprises the first step of mine soil trimming, the second step of soil structure fertility recovery, the third step of planting pretreatment, the fourth step of greening planting and the fifth step of slope greening treatment. According to the method, heavy metal removal treatment and water-stable aggregate shaping are carried out on the mine soil, so that the fertility and durability of the mine soil are effectively improved, the problem that only short-term greening planting can be carried out after treatment by a traditional method is solved, and long-term ecological restoration is really realized; and meanwhile, after the mine slope section is reinforced, lawn seed guniting treatment is matched, so that the stability of the mine slope section is effectively improved, and a very good greening recovery effect can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of mine ecological restoration, and in particular to a mine restoration and greening method. Background Art

[0002] With the improvement of mineral prospecting technology and mineral development technology and the substantial increase in energy demand, the speed of mine development is also accelerating. Mineral mining and mine development, while accelerating economic development, have caused serious damage to the ecological environment of mines and their surroundings, and the structure and function of the ecosystem have undergone great degradation. After the mining activities are completed, the environment of the surrounding areas of mines is damaged, resulting in soil scarcity. Due to mining, most of the soil matrix is ​​contaminated with heavy metals or is poor in fertility.

[0003] Traditional ecological restoration is to improve soil conditions by fertilizing cultivated land and planting green plants, but this method can only solve short-term planting problems. After the long-term green plants absorb all the nutrients, the soil will still return to its original barren level and cannot achieve long-term development. At the same time, for the mine slope section, only protective nets are used for rockfall protection, and overall greening restoration cannot be achieved. Therefore, the present invention proposes a mine restoration and greening method to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to propose a mine restoration and greening method, which effectively increases the fertility and durability of the mine soil by removing heavy metals and shaping water-stable aggregates from the mine soil, avoiding the problem that traditional methods can only be used for short-term greening planting, and truly achieving long-term ecological restoration. At the same time, the reinforcement of the mine slope section and the lawn seed spraying treatment effectively increase the stability of the mine slope section, and can also achieve a good effect of restoring greening.

[0005] To achieve the purpose of the present invention, the present invention is implemented by the following technical scheme: a mine restoration and greening method, comprising the following steps:

[0006] Step 1: Mine soil remediation: first, the mine is prepared, and then hyperaccumulator plants are planted to adsorb and remove heavy metals in the mine soil to form harmless mine soil;

[0007] Step 2: Soil structure and fertility recovery: water-stable aggregate plasticization treatment is performed on the repaired mine soil, and then compound fertilizer and humus fertilizer are spread and plowed. After plowing, a layer of dead branches and leaves is spread, and a layer of plowed mine soil is spread on the dead branches and leaves again. Finally, a layer of three-dimensional vegetation net is covered and watered thoroughly, waiting for decomposition;

[0008] Step 3: Pre-planting treatment: mark the planting points on the soil of the planting site at 80-100 cm plant spacing and 100-120 cm row spacing, separate the planting openings with the three-dimensional vegetation net on the surface of the marked points and dig a 20-30 cm deep planting pit, spread base fertilizer in the planting pit and fill it with 5 cm depth;

[0009] Step 4: Greening Planting: Plant the greening plants according to the planting pits, cover the roots with soil and compact them after planting, then water them thoroughly, and carry out regular post-planting management;

[0010] Step 5: Slope greening treatment: first use anchor rods and slope protection nets to protect and reinforce the mine slopes, then mix soil, organic fertilizer, water retaining agent, water and lawn seeds into a paste and apply it to the reinforced mine slopes. When the lawn grows, the slope greening is completed.

[0011] A further improvement is that during the land preparation in step 1, a stone picker is first used to remove stones and debris in the soil, and then the soil is deep-turned and the soil blocks are crushed by a crusher to loosen the hard soil; the deep turning depth is controlled at 20-50 cm, and for soil layers that do not meet the depth standards, the deep turning is performed to a depth of 5 cm from the rock layer.

[0012] A further improvement is that: the hyperaccumulator plant planted in step 1 is specifically

[0013] S1. First, water the soil after land preparation, and then use the electrodynamic repair method to pass direct current to the soil for 4-5 days, during which the soil moisture is maintained;

[0014] S2. Sampling and testing the distribution of heavy metals in the soil according to the direction of the energized electrodes, and dividing the blocks according to the test results;

[0015] S3. After dividing the blocks, apply soil remediation agent, then plant hyperaccumulators at high density in the blocks with high heavy metal content, and plant hyperaccumulators at low density in the blocks with low heavy metal content;

[0016] S4. After the hyperaccumulator plants are planted, small-scale restoration algae are spread again in the areas with high heavy metal content, and regular sampling and testing are carried out. After the heavy metal content is reduced to the standard level, the hyperaccumulator plants are removed to complete the heavy metal adsorption and removal.

[0017] A further improvement is that the soil remediation agent in S3 is prepared by mixing alkaline modifier, sepiolite, zeolite, rare earth lanthanum and organic matter in a weight ratio of 40:15:15:5:25.

[0018] A further improvement is that: the water-stable aggregate plasticizing treatment in step 2 is specifically

[0019] Step 1: First, sprinkle water on the soil to moisten it, then spread the crop roots and stubble on the surface and continue to sprinkle water to make it moist and rotten;

[0020] Step 2: After the crop roots and stubble have rotted to form humus, a layer of bentonite is spread, followed by deep plowing, which is the same as the deep plowing of the land preparation process in step 1;

[0021] Step 3: After deep plowing, use the land as a nursery plot for short-term planting to cultivate seedlings with well-developed root systems, and transplant the seedlings regularly.

[0022] Further improvements are: in the second step, the bentonite spreading standard is 90-110 kg / mu; in the third step, after the seedlings are transplanted, the water-stable aggregates in the soil are screened and tested by wet screening, and whether to continue to use it as a nursery ground to cultivate seedlings is decided based on the test results.

[0023] A further improvement is that the specific operation of the wet sieving method is to take equal amounts of soil from samples in different blocks, soak them in pure water, and then put them into the top layer of the sieve; place the sieve in a pure water environment for vibrating, with a vibration amplitude of 2 cm and a vibration frequency of 50 times / min; then remove the vibrating sieve and transfer the aggregates to different containers without loss to obtain water-stable aggregates, and measure the number and particle size of the water-stable aggregates during detection.

[0024] A further improvement is that the soil mixed in step five is collected from the soil after the soil structure and fertility are restored in step two, wherein the mass ratio of soil, organic fertilizer, water retaining agent, water and lawn seeds is 55:10:5:25:5, a mixer is used for sufficient mixing, and then a sprayer is used for coating.

[0025] The beneficial effects of the present invention are as follows: the present invention effectively increases the fertility and durability of the mine soil by removing heavy metals and shaping water-stable aggregates from the mine soil, avoiding the problem that traditional methods can only provide short-term greening and planting, and truly achieving long-term ecological restoration. At the same time, the reinforcement of the mine slope section and the lawn seed spraying treatment effectively increase the stability of the mine slope section, and can also achieve a good effect of restoring greening, providing a reliable and long-lasting greening ecological restoration method for mine ecological restoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is a flow chart of the method of the present invention.

[0027] Figure 2 This is a flow chart of the cultivation of hyperaccumulator plants according to the present invention.

[0028] Figure 3 This is a flow chart of the water-stable aggregate molding process of the present invention. DETAILED DESCRIPTION

[0029] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0030] according to Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a mine restoration and greening method, comprising the following steps:

[0031] Step 1: Mine soil remediation: first, the mine is prepared, and then hyperaccumulator plants are planted to adsorb and remove heavy metals in the mine soil to form harmless mine soil;

[0032] When preparing the land, first use a stone picker to remove stones and debris from the soil, then deep-turn the soil and use a crusher to crush the hard soil blocks and loosen the hard soil; the deep turning depth is controlled at 20-50cm. If the soil layer depth does not meet the standard, deep turning to a depth of 5cm from the rock layer is sufficient;

[0033] Planting hyperaccumulators specifically includes:

[0034] S1. First, water the soil after land preparation, and then use the electrodynamic repair method to pass direct current to the soil for 4-5 days, during which the soil moisture is maintained;

[0035] S2. Sampling and testing of soil heavy metal distribution in the direction of the energized electrodes, and dividing the blocks according to the test results. Due to the attraction of DC to heavy metal ions, the heavy metal ion content near the two ends of the DC motor is the highest, and gradually decreases from the two sides to the middle. Therefore, the blocks are divided into three blocks according to the heavy metal ion content. The blocks near the motor ends on both sides are high in heavy metal content, and the central block is low in heavy metal content.

[0036] S3. After dividing the blocks, apply soil remediation agent, then plant hyperaccumulators at high density in the blocks with high heavy metal content, and plant hyperaccumulators at low density in the blocks with low heavy metal content;

[0037] The soil remediation agent is made of alkaline improver, sepiolite, zeolite, rare earth lanthanum and organic matter in a ratio of 40:15:15:5:25; the planting density of hyperaccumulator plants is controlled according to the divided blocks, which can effectively absorb heavy metal ions without incomplete absorption of heavy metal ions;

[0038] S4. After the hyperaccumulators are planted, small-scale restoration algae are spread again in the areas with high heavy metal content, and regular sampling and testing are carried out. Small-scale restoration algae can maintain the fluffiness and moisture of the soil while absorbing heavy metal ions, avoiding the hardening of the land. After the heavy metal content is reduced to the standard level, the hyperaccumulators are removed to complete the adsorption and removal of heavy metals.

[0039] Small-scale restoration algae can also attract some microorganisms to reproduce, and microbial reproduction can effectively increase soil fertility, realize ecological cycle, and meet the conditions for long-term development.

[0040] Step 2: Soil structure and fertility recovery: water-stable aggregate plasticization treatment is performed on the repaired mine soil, and then compound fertilizer and humus fertilizer are spread and plowed. After plowing, a layer of dead branches and leaves is spread, and a layer of plowed mine soil is spread on the dead branches and leaves again. Finally, a layer of three-dimensional vegetation net is covered and watered thoroughly, waiting for decomposition;

[0041] The decomposition of dead branches and leaves forms humus fertilizer, which not only increases the fertility of the soil, but also provides a good living and breeding environment for microbial communities;

[0042] The specific treatment of water-stable aggregates is as follows:

[0043] Step 1: First, sprinkle water on the soil to moisten it, then spread the crop roots and stubble on the surface and continue to sprinkle water to make it moist and rotten;

[0044] Step 2: After the crop roots and stubble have rotted to form humus, spread a layer of bentonite, and then deep plowing is carried out. The deep plowing depth is controlled at 20-50cm. For those whose soil layer depth does not meet the standard, deep plowing to a depth of 5cm from the rock layer is sufficient; and for the blocks of surface soil, part of the soil can be transferred from the deep soil blocks to the surface soil blocks for greening planting, and gradient planting can be formed between the height differences of the soil layers;

[0045] The standard for spreading bentonite is 90-110kg / mu; in step 3, after the seedlings are transplanted, the water-stable aggregates in the soil are screened by wet screening and tested, and the decision on whether to continue to use the nursery ground for seedling cultivation is made based on the test results;

[0046] The specific operation of wet sieving is to take equal amounts of soil from samples in different blocks, soak them in pure water and put them on the top layer of the sieve; place the sieve in a pure water environment and vibrate the sieve with an amplitude of 2 cm and a frequency of 50 times / min; then remove the vibrating sieve and transfer the aggregates to different containers without loss to obtain water-stable aggregates. During the test, the number and particle size of the water-stable aggregates are measured respectively;

[0047] Step 3. After deep plowing, use the land as a nursery plot for short-term planting to cultivate seedlings with well-developed root systems, and transplant the seedlings regularly. The remaining roots of seedlings with well-developed root systems after digging out and transplanting the seedlings can greatly increase the number and particle size of water-stable aggregates, and can also increase soil fertility when rot occurs.

[0048] Step 3: Pre-planting treatment: mark the planting points on the soil of the planting site at 80-100cm plant spacing and 100-120cm row spacing, separate the planting openings with the three-dimensional vegetation net on the surface of the marked points and dig a 20-30cm deep planting pit. The diameter of the planting pit is determined according to the root size of the greening plants to be planted. Apply base fertilizer in the planting pit and fill it 5cm deep.

[0049] Step 4: Greening Planting: Plant the greening plants according to the planting pits, cover the roots with soil and compact them after planting, then water them thoroughly, and carry out regular post-planting management;

[0050] During post-planting management, fertilizers needed for the growth of small-scale algae and plants should be regularly applied to supplement the soil, and water should be applied regularly. Soil fertility should be sampled regularly to record the characteristics of changes.

[0051] Step 5: Slope greening treatment: firstly, anchor rods and slope protection nets are used to protect and reinforce the mine slopes, then soil, organic fertilizer, water retaining agent, water and lawn seeds are mixed into a paste and applied to the reinforced mine slopes. When lawns grow, the slope greening is completed.

[0052] The mixed soil is collected from the soil after the soil structure and fertility are restored in step 2, wherein the mass ratio of soil, organic fertilizer, water retaining agent, water and lawn seeds is 55:10:5:25:5. A mixer is used for sufficient mixing, and then a sprayer is used for coating.

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A mine restoration and greening method, It is characterized in that The following steps are involved: Step 1: Mine soil remediation: first, the mine is prepared, and then hyperaccumulator plants are planted to adsorb and remove heavy metals in the mine soil to form harmless mine soil; Step 2: Soil structure and fertility recovery: water-stable aggregate plasticization treatment is performed on the repaired mine soil, and then compound fertilizer and humus fertilizer are spread and plowed. After plowing, a layer of dead branches and leaves is spread, and a layer of plowed mine soil is spread on the dead branches and leaves again. Finally, a layer of three-dimensional vegetation net is covered and watered thoroughly, waiting for decomposition; Step 3: Pre-planting treatment: mark the planting points on the soil of the planting site at 80-100 cm plant spacing and 100-120 cm row spacing, separate the planting openings with the three-dimensional vegetation net on the surface of the marked points and dig a 20-30 cm deep planting pit, spread base fertilizer in the planting pit and fill it with 5 cm depth; Step 4: Greening Planting: Plant the greening plants according to the planting pits, cover the roots with soil and compact them after planting, then water them thoroughly, and carry out regular post-planting management; Step 5: Slope greening treatment: first use anchor rods and slope protection nets to protect and reinforce the mine slopes, then mix soil, organic fertilizer, water retaining agent, water and lawn seeds into a paste and apply it to the reinforced mine slopes. When the lawn grows, the slope greening is completed.

2. A mine restoration and greening method according to claim 1, Features: During the land preparation in step 1, a stone picker is first used to remove stones and debris in the soil, and then the soil is deep-turned and the soil clods are crushed by a crusher to loosen the hard soil; the deep turning depth is controlled at 20-50 cm, and for soil layers that do not meet the depth standards, the deep turning is performed to a depth of 5 cm from the rock layer.

3. A mine restoration and greening method according to claim 1, Features: The step 1 of planting the hyperaccumulator plants is specifically as follows: S1. First, water the soil after land preparation, and then use the electrodynamic repair method to pass direct current to the soil for 4-5 days, during which the soil moisture is maintained; S2. Sampling and testing the distribution of heavy metals in the soil according to the direction of the energized electrodes, and dividing the blocks according to the test results; S3. After dividing the blocks, apply soil remediation agent, then plant hyperaccumulators at high density in the blocks with high heavy metal content, and plant hyperaccumulators at low density in the blocks with low heavy metal content; S4. After the hyperaccumulator plants are planted, small-scale restoration algae are spread again in the areas with high heavy metal content, and regular sampling and testing are carried out. After the heavy metal content is reduced to the standard level, the hyperaccumulator plants are removed to complete the heavy metal adsorption and removal.

4. A mine restoration and greening method according to claim 3, Features: The soil remediation agent in S3 is prepared by mixing alkaline improver, sepiolite, zeolite, rare earth lanthanum and organic matter in a ratio of 40:15:15:5:

25.

5. A mine restoration and greening method according to claim 1, Features: The water-stable aggregate plasticizing treatment in step 2 is specifically as follows: Step 1: First, sprinkle water on the soil to moisten it, then spread the crop roots and stubble on the surface and continue to sprinkle water to make it moist and rotten; Step 2: After the crop roots and stubble have rotted to form humus, a layer of bentonite is spread, followed by deep plowing, which is the same as the deep plowing of the land preparation process in step 1; Step 3: After deep plowing, use the land as a nursery plot for short-term planting to cultivate seedlings with well-developed root systems, and transplant the seedlings regularly.

6. A mine restoration and greening method according to claim 5, Features: In the second step, the bentonite spreading standard is 90-110 kg / mu; in the third step, after the seedlings are transplanted, the water-stable aggregates in the soil are screened and tested by wet screening method, and whether to continue to use it as a nursery ground to cultivate seedlings is determined based on the test results.

7. A mine restoration and greening method according to claim 6, Features: The specific operation of the wet sieving method is to take equal amounts of soil from samples in different blocks, soak them in pure water, and then put them into the top layer of the sieve; place the sieve in a pure water environment for vibrating, with a vibration amplitude of 2 cm and a vibration frequency of 50 times / min; then remove the vibrating sieve and transfer the aggregates to different containers without loss to obtain water-stable aggregates, and measure the number and particle size of the water-stable aggregates during detection.

8. A mine restoration and greening method according to claim 1, Features: The soil mixed in step five is collected from the soil after the soil structure and fertility are restored in step two, wherein the mass ratio of soil, organic fertilizer, water retaining agent, water and lawn seeds is 55:10:5:25:

5. The mixing is performed by a mixer and then coated by a sprayer.

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