Method for repairing karst mountainous region in extremely arid region under condition of no soil collapse

Abstract

The invention discloses a method for repairing a karst mountain land in an extremely arid area under the condition of no soil collapse, belongs to the field of mine repairing, and aims to solve the problems that a certain strip mine belongs to a desert gobi area, the main type of soil is gypsum ash brown desert soil, the precipitation amount is small, the evaporation amount is large, and phytoremediation is difficult. The remediation object is the desert gobi area mine soil, the soil is mud left after mineral products are removed and the mineral products are deeply excavated by hundreds of meters, and the mud comes from hundreds of meters underground and hardly contains microorganisms; meanwhile, the saline-alkali content of the soil is very high. Different from the prior art, the remediation method provided by the invention adopts a manner of not killing soil, adopts the suaeda salsa as a remediation plant, and adopts a drip irrigation manner to ensure the water supply of the suaeda salsa, so that the remediation of the mine soil is realized. According to statistics, the total irrigation quota of the whole growth period of the suaeda salsa is 80-100 m < 3 > / mu, and the water consumption is obviously lower than the water consumption required by an existing remediation scheme.

Description

Technical Field

[0001] The present application relates to the field of soil remediation, especially the field of mine remediation, and specifically to a method for remediating karst mountains in extremely arid areas under non-soil-hauling conditions. More specifically, the present application provides a method for in-situ soil remediation of mines in extremely arid areas, which is based on the residual soil after mining, and can achieve land reclamation without transporting soil externally, thereby realizing the ecological restoration of mines in extremely arid areas. Background Art

[0003] Mine land reclamation is a method and process for surveying, planning, filling, renovating, developing and utilizing the land abandoned due to mining. This activity aims to restore the land damaged by mining activities and make it regain its usability, whether as cultivated land, forest land, grassland or other construction land.

[0005] The land reclamation of production and construction mines mainly focuses on restoring and protecting the ecological environment of the mining area on the basis of maintaining existing production activities, so as to reduce the pollution and damage of mining activities to the environment and ensure minimizing the negative impact on the ecological environment during the mining process. The land reclamation of historically-remnant mines is to completely eliminate the pollution and damage caused by mining production to the local environment after the resources in the mining area are basically exhausted and the production activities are completed, and to carry out the comprehensive reclamation of the soil and the reconstruction of the ecological environment, so as to make full use of the land resources again and realize the restoration and improvement of the ecological environment.

[0006] An open-pit mine is in the production stage. The mining area belongs to the desert gobi area, and the main soil type is gypsum gray-brown desert soil. The soil parent material is mostly gravelly proluvial or alluvial-proluvial material, with a high gravel content in the soil, gravel on the surface, and a porous and scaly crust layer on the surface. The physical and chemical properties of the soil are shown in Table 1 below. The mining area has a typical continental arid climate, with little rain and strong winds all year round. Statistical data shows that: the average annual temperature in this area is 8°C, the hottest month is July, with the highest temperature of 40.3°C, the coldest month is January, with the lowest temperature of -28.5°C; the average annual precipitation is 199 mm, and the average annual evaporation is 1716 mm; the high-temperature period is from June to September, and the winter is from November to March; the average annual wind speed is 5.9 m / s, the maximum wind speed is 27 m / s, the most frequent wind direction is the west wind, with a frequency of 21, and the strong winds above level 7 occur 115.5 days on average per year; the freezing period is from November to March of the following year, the maximum frost depth is about 0.8 m, and the maximum snow depth is 0.24 m.

[0007] Table 1 Analysis of Soil Physical and Chemical Properties and Evaluation of Fertility Indexes

[0008] How to achieve the soil remediation of the above mining area has become an urgent problem to be solved. Summary of the Invention

[0009] The object of the invention of the present application is: aiming at the problem that an open-pit mine belongs to a desert and gobi area, the main type of soil is gypsum gray-brown desert soil, the precipitation is low, the evaporation is large, and it is difficult to carry out phytoremediation, to provide a method for restoring karst mountains in extremely arid areas without soil excavation.

[0010] In order to achieve the above object, the present application adopts the following technical solutions: A method for restoring karst mountains in extremely arid areas without soil excavation uses Suaeda salsa as the restoration plant and adopts drip irrigation to ensure the water supply of Suaeda salsa.

[0011] An in-situ soil restoration method for mines in extremely arid areas is based on the residual soil after mine excavation, uses Suaeda salsa as the restoration plant, and adopts drip irrigation to ensure the water supply of Suaeda salsa, so as to realize the in-situ ecological restoration of the mine by Suaeda salsa. More specifically, it is an in-situ restoration method for saline-alkali soil generated by mine excavation in desert and gobi areas.

[0012] Do not perform desalination treatment on the residual soil after mine excavation, and directly plant Suaeda salsa plants.

[0013] It is not necessary to add transported soil on the surface of the residual soil after mine excavation, and land reclamation can be realized, and ecological restoration of mines in extremely arid areas can be achieved.

[0014] The residual soil after mine excavation is saline-alkali soil.

[0015] It includes the following steps: (1) Level the land; (2) Adopt the two-pipe and three-row method to lay the capillary drip irrigation belt, and the distance between the capillary drip irrigation belts is 0.4 - 0.7 m; (3) Excavate planting holes, and add base fertilizer to the planting holes; the depth of the planting holes is 3 - 25 cm, the diameter of the planting holes is 10 - 25 cm, and the application amount of the base fertilizer is 0.5 - 0.6 kg / planting hole; (4) Select early May as the sowing period, mix Suaeda salsa seeds with water-retaining agent until they are loose grains, and plant the loose grains in the planting holes; among them, the application amount of the water-retaining agent is 2 - 3 g / planting hole, and the amount of Suaeda salsa seeds is 0.2 - 0.3 kg / mu; (5) After sowing the seeds, carry out drip irrigation. Each irrigation degree is until the wetting ranges of adjacent capillaries overlap, and each watering is at sunset in the afternoon. The total irrigation quota for the whole growth period is 80 - 100 m 3 / mu; Among them, it enters the germination period between May and June. The drip irrigation is more frequent during the germination period, with a water dripping interval of once every 2 days, and the amount of each drip irrigation is 1.2 - 1.7 m 3; / mu; Enter the seedling stage between July and August. During the seedling stage, drip water once every other day, with a drip irrigation amount of 1.2 - 1.7 m 3 / mu; Enter the seedling establishment stage in September. During the seedling establishment stage, drip water once every 3 days, with a drip irrigation amount of 1.2 - 1.7 m 3 / mu; Enter the overwintering stage of Suaeda salsa in October. During the overwintering stage of Suaeda salsa, drip water once every 6 days, with a drip irrigation amount of 1.2 - 1.7 m 3 / mu.

[0016] In the step (1), use the residual soil after mine exploitation in the desert gobi area as the planting substrate, and the salt content of the planting substrate is 1.5wt% - 2.5wt%; regard the karst mountain area in the extremely arid area where the planting substrate is located as the area to be repaired; before sowing in the area to be repaired, finely crush and level the surface soil for standby.

[0017] In the step (1), before sowing in the area to be repaired, use a plow and harrow to finely crush and level the surface soil for standby.

[0018] In the step (2), the specific information about laying the capillary drip irrigation belt in the two - pipe and three - row method is as follows: Two pipes refer to the drip irrigation belt composed of two capillary drip irrigation belts; Three rows refer to three planting rows, with two planting rows on the outside of the drip irrigation belt and one planting row between the two drip irrigation belts.

[0019] In the step (2), the distance between the capillary drip irrigation belts is about 0.5 m.

[0020] In the step (5), and each watering is after 7 p.m.

[0021] In the step (5), enter the germination stage between May and June. Drip irrigation is relatively frequent during the germination stage, drip water once every 2 days, with a drip irrigation amount of 1.5 m 3 / mu; Enter the seedling stage between July and August. During the seedling stage, drip water once every other day, with a drip irrigation amount of 1.5 m 3 / mu; Enter the seedling establishment stage in September. During the seedling establishment stage, drip water once every 3 days, with a drip irrigation amount of 1.5 m 3 / mu; Enter the overwintering stage of Suaeda salsa in October. During the overwintering stage of Suaeda salsa, drip water once every 6 days, with a drip irrigation amount of 1.5 m 3 / mu.

[0022] In view of the foregoing problems, the present application provides a method for restoring karst mountains in extremely arid areas under non-soil conditions, which is a method for restoring gypsum gray-brown desert soil in desert and gobi areas. The present application is mainly used for mine restoration in desert and gobi areas. The main type of soil is gypsum gray-brown desert soil, with little precipitation and large evaporation, making plant restoration difficult. For mine restoration, the common treatment measure is to replace the soil, that is, to use fertile soil to restore the mine to be restored. The fertile soil contains a large number of microorganisms, and the average restoration price is more than 150,000 yuan. At the same time, under normal circumstances, the water requirement for soil restoration per mu in desert areas is about 500 cubic meters.

[0023] The restoration object of the present application is the mine soil in desert and gobi areas. This soil is the slurry remaining after the removal of minerals through deep excavation of several hundred meters. Such slurry comes from hundreds of meters underground and contains almost no microorganisms. At the same time, the salinity content of this soil is very high.

[0024] Different from the prior art, the restoration method provided by the present application adopts a non-soil method (non-soil means not using external soil), that is, in-situ restoration; by using Suaeda salsa as the restoration plant and adopting drip irrigation to ensure the water supply of Suaeda salsa, the restoration of mine soil is achieved. After statistics, using the present invention, the total irrigation quota of Suaeda salsa during the whole growth period is 80-100 m 3 / mu, which is significantly lower than the water consumption required by the existing restoration scheme. After measurement, in a 1.5-acre restoration area, the actual water consumption during the whole growth period of Suaeda salsa is 82 m 3 , showing a significant water-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be described by way of examples and with reference to the accompanying drawings, where: Figure 1 It is a sowing site diagram in Example 1.

[0026] Figure 2 It is a layout diagram of "two pipes and three rows" capillary drip irrigation tape in Example 1.

[0027] Figure 3 It is a restoration site diagram of karst mountains in extremely arid areas in Example 1. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] All the features disclosed in this specification, or all the steps in any method or process disclosed, except for mutually exclusive features and / or steps, can be combined in any way.

[0029] Any feature disclosed in this specification, unless specifically described, can be replaced by other equivalent or similar-purpose alternative features. That is, unless specifically described, each feature is only an example of a series of equivalent or similar features.

[0030] Example 1 In 2023 - 2024, the karst mountains in the extremely arid area of a certain company in Santanghu Development Zone, Hami were restored, with an application demonstration area of 100 mu. The relevant operations are as follows.

[0031] (1)The experimental plot selected the soil of karst mountains in the arid area with a salt content of 1.5 - 2.5% in the 0 - 25 cm soil layer. Before sowing, plowing and harrowing operations were carried out to make the surface soil flat and fine.

[0032] (2)The capillary drip irrigation belt was laid out in the "two - pipe and three - row" method, and the spacing between the drip irrigation capillaries was about 0.5 m.

[0033] (3)Planting holes were dug, and base fertilizer was added to the planting holes. The depth of the planting holes was about 3 - 25 cm, the diameter of the planting holes was 10 - 25 cm, the application amount of base fertilizer was 0.5 - 0.6 kg / planting hole, and the base fertilizer was evenly spread along the bottom of the planting hole.

[0034] (4)The sowing period was selected in early May 2023. The Suaeda salsa seeds were mixed with water - retaining agent until they were in loose grains, and the loose grains were planted in the planting holes; among them, the application amount of water - retaining agent was 2 - 3 g / planting hole, and the Suaeda salsa seeds were 0.2 - 0.3 kg / mu.

[0035] (5)After sowing the seeds, drip irrigation was carried out. Each irrigation was carried out until the wetting ranges of adjacent capillaries overlapped, and each watering was carried out after 7 pm. The total irrigation quota for the whole growth period was 80 - 100 m 3 / mu. Drip irrigation was more frequent during the germination period. From May to June, drip irrigation was carried out once every 2 days, and the amount of each drip irrigation was 1.5 m 3 / mu; from July to August, drip irrigation was carried out once every 1 day, and the amount of each drip irrigation was 1.5 m 3 / mu; in September, drip irrigation was carried out once every 3 days, and the amount of each drip irrigation was 1.5 m 3 / mu; in October, drip irrigation was carried out once every 6 days, and the amount of each drip irrigation was 1.5 m 3 / mu.

[0036] In this embodiment, the water-retaining agent used is a commercially available product, and during the restoration process, the method of transporting mature soil from outside is not adopted. The restoration of saline-alkali soil usually requires a large amount of water. As mentioned above, under normal circumstances, the water demand for soil restoration in each mu of desert area is about 500 cubic meters. As mentioned above, the mine soil in the desert and gobi area of this application comes from hundreds of meters underground, and it contains almost no microorganisms; at the same time, the saline-alkali content of this kind of soil is very high. For soils with a high saline-alkali content, there are many plants that can adapt; but the microorganisms in the soil are also one of the key factors for plant growth, which makes it difficult for most plants to exist in soil without microorganisms, let alone in high-saline-alkali content soil without microorganisms. Using Suaeda salsa in this application to achieve the restoration of this kind of soil is actually an accidental discovery of the inventor. The inventor found that by adopting the solution of this application, Suaeda salsa can survive in high-saline-alkali content soil without microorganisms, and significantly reduces the required water consumption, which cannot be achieved by ordinary plant soil restoration methods.

[0037] Furthermore, in this application, Suaeda salsa seeds are mixed with a water-retaining agent to form loose granules, which further reduces the consumption of the required water resources through the cooperation of the water-retaining agent and the capillary drip irrigation belt. This application has obvious progressive significance for promoting the conservation and rational utilization of water resources and realizing the soil restoration of karst mountains in extremely arid areas under the condition of not using soil.

[0038] It is measured that in this embodiment, the actual average water consumption of Suaeda salsa during the whole growth period is 85.7 m 3 / mu.

[0039] Example 2 In 2024, the inventor carried out in-situ restoration of mine soil in a certain extremely arid karst mountain area in Xiaoguai Township, Santanghu, Hami, and the application demonstration area was 100 mu. The relevant operations are as shown in Example 1.

[0040] It is measured that in this embodiment, the actual average water consumption of Suaeda salsa during the whole growth period is 88.3 m 3 / mu.

[0041] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, and to any new method or process step or any new combination disclosed.

Claims

1. A method for restoring karst mountains in extremely arid areas under non-ket soil conditions, characterized in that, Use Suaeda salsa as the restoration plant and adopt drip irrigation to ensure the water supply of Suaeda salsa.

2. The repair method according to claim 1, wherein Based on the residual soil after mine exploitation, use Suaeda salsa as the restoration plant and adopt drip irrigation to ensure the water supply of Suaeda salsa, so as to realize the in-situ ecological restoration of the mine by Suaeda salsa.

3. The repair method according to claim 1 or 2, characterized in that, Do not desalinate the residual soil after mine exploitation and directly plant salt-tolerant plants.

4. The repair method according to any one of claims 1 to 3, characterized in that, It includes the following steps: (1) Level the land; (2) Adopt the two-pipe and three-row method to lay the capillary drip irrigation belt, and the distance between the capillary drip irrigation belts is 0.4 - 0.7 m; (3) Dig planting holes and add base fertilizer into the planting holes; the depth of the planting holes is 3 - 25 cm, the diameter of the planting holes is 10 - 25 cm, and the application amount of the base fertilizer is 0.5 - 0.6 kg / planting hole; (4) Select the beginning of May as the sowing period, mix the Suaeda salsa seeds with water-retaining agent until they are loose grains, and plant the loose grains in the planting holes; among them, the application amount of the water-retaining agent is 2 - 3 g / planting hole, and the Suaeda salsa seeds are 0.2 - 0.3 kg / mu; (5) After sowing the seeds, drip irrigation is carried out. The degree of each irrigation is until the wetting ranges of adjacent capillary tubes overlap, and each watering is carried out at sunset in the afternoon. The total irrigation quota for the whole growth period is 80 - 100 m 3 / mu; Among them, it enters the germination period between May and June. Drip irrigation is relatively frequent during the germination period, with a water dripping interval of 2 days, and the amount of drip irrigation per time is 1.2 - 1.7 m 3 / mu; it enters the seedling period between July and August. During the seedling period, the water dripping interval is 1 day, and the amount of drip irrigation per time is 1.2 - 1.7 m 3 / mu; it enters the seedling establishment period in September. During the seedling establishment period, the water dripping interval is 3 days, and the amount of drip irrigation per time is 1.2 - 1.7 m 3 / mu; it enters the overwintering period of Suaeda salsa in October. During the overwintering period of Suaeda salsa, the water dripping interval is 6 days, and the amount of drip irrigation per time is 1.2 - 1.7 m 3 / mu.

5. The repair method according to claim 4, characterized in that, In the step (1), use the residual soil after mine exploitation in the desert gobi area as the planting substrate, and the salt content of the planting substrate is 1.5 wt% - 2.5 wt%; regard the karst mountain area in the extremely arid area where the planting substrate is located as the area to be restored; before sowing in the area to be restored, finely crush and level the surface soil for standby.

6. The repair method according to claim 4 or 5, characterized in that In the step (2), the specific information about laying the capillary drip irrigation belt in the two-pipe and three-row method is as follows: the two pipes refer to the drip irrigation belts composed of two capillary drip irrigation belts; the three rows refer to three planting rows, two planting rows are located outside the drip irrigation belts, and one planting row is located between the two drip irrigation belts.

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