Desert soil improvement method

Abstract

The invention relates to the technical field of waste biomass resource utilization and desert control, in particular to a desert soil improvement method which comprises the following steps: A) uniformly mixing sludge generated by urban sewage treatment with crop waste materials to obtain a mixed material; b) paving the mixed material under the desert earth surface, and sealing the mixed material with sand; c) irrigating to ensure that water permeates the sand covering layer and the mixed material layer; d) uniformly applying a water-retaining liquid mulching film on the surface of the sand covering layer; and E) fermenting under the condition of drip irrigation, and then sowing desert plants. According to the method, the composting technology can be well combined with a drip irrigation system for application, meanwhile, the water-retaining liquid mulching film is matched, waste is recycled, the defect of high evaporation of water in the desert area is overcome, the humification process of compost is accelerated by utilizing the characteristic of high temperature of the desert, and the yield of the desert is increased. The desert soil improvement is scientifically and effectively carried out while comprehensive management and resource utilization of organic wastes are realized.

Description

Technical Field

[0001] The invention relates to the fields of waste biomass resource utilization technology and desert control technology, and in particular to a method for improving desert soil. Background Art

[0002] Desertification is a serious environmental problem facing the world today. It leads to the decline of land productivity, ecosystem degradation, reduction of biodiversity, and has a huge impact on human social and economic activities. Desertified areas are generally plagued by water shortages, soil quality deterioration, and low vegetation coverage. These problems have aggravated the fragility of the ecological environment and threatened the sustainable development of the region.

[0003] Although there are many desert control methods, such as vegetation restoration, soil and water conservation, and drip irrigation technology, these methods are often costly, difficult to implement, and difficult to achieve significant results in the short term. In particular, there is still a lack of efficient and sustainable solutions in terms of how to effectively utilize limited resources in desertified areas and achieve both ecological and economic benefits.

[0004] In the process of desertification control, how to utilize waste biomass as a resource and convert it into organic matter that is beneficial to vegetation restoration and soil improvement has become a hot topic of research. Patent application document CN102295478A discloses a method for accelerating the composting of garden waste using chemical decomposition agents. Patent application document CN 112898056 A discloses an advanced technology for the resource utilization of urban domestic sludge, which achieves harmless, reduced and resource utilization of sludge by mixing urban domestic sludge with poultry and livestock manure, auxiliary materials and high-temperature resistant biological agents in a certain proportion for fermentation. The special environment of desertified areas puts higher requirements on the composting process, such as solving problems such as fast evaporation of water, serious nutrient loss and low microbial activity. Therefore, developing a composting technology that adapts to the characteristics of desertified areas can not only effectively treat waste biomass, but also provide high-quality organic fertilizers for desert control, which is of great significance for promoting ecological restoration and sustainable development in desertified areas.

[0005] At present, there is no research report proposing a comprehensive technology that is tailored to the characteristics of desertified areas and can efficiently convert waste biomass while improving compost quality and desert control efficiency. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a method for improving desert soil, which can efficiently convert waste biomass and improve compost quality and desert management efficiency.

[0007] The present invention provides a method for improving desert soil, comprising the following steps:

[0008] A) mixing sludge produced by municipal sewage treatment with crop waste materials to obtain a mixed material;

[0009] B) laying the mixed material under the desert surface and sealing it with sand to obtain a mixed material layer and a covering sand layer;

[0010] C) Carry out irrigation to ensure that water penetrates the sand cover and the mixed material layer;

[0011] D) uniformly applying a water-retaining liquid ground film on the surface of the sand covering layer;

[0012] E) Fermentation is carried out under drip irrigation conditions and then desert plants are sown.

[0013] Preferably, in step A), the carbon-nitrogen ratio of the mixed material is 20-25:1.

[0014] Preferably, in step A), the crop waste material is selected from straw; and the size of the crop waste material is 1 to 3 cm.

[0015] Preferably, in step B), the mixed material is laid 15 to 35 cm below the ground surface.

[0016] Preferably, in step C), irrigation is performed by drip irrigation;

[0017] The drip irrigation system is a drip irrigation belt; the drip irrigation belt is laid 8 to 12 cm below the sand layer.

[0018] Preferably, in step C), the irrigation time is 22 to 26 hours.

[0019] Preferably, in step D), 1 to 2 hours after the irrigation is completed, a water-retaining liquid mulch film is uniformly applied on the surface of the sand layer.

[0020] Preferably, in step E), the drip irrigation time is 7 to 15 days.

[0021] Preferably, in step E), sowing desert plants specifically comprises:

[0022] Desert plant seeds are sown in holes beside the drip irrigation belt using a seeder; the seeder requires that each hole be 5 to 7 cm apart.

[0023] The present invention provides a method for improving desert soil, comprising the following steps: A) mixing sludge generated by urban sewage treatment with crop waste materials to obtain a mixed material; B) laying the mixed material under the desert surface, sealing it with sand, and obtaining a mixed material layer and a sand-covered layer; C) irrigating to ensure that water penetrates the sand-covered layer and the mixed material layer; D) applying a water-retaining liquid mulch film evenly on the surface of the sand-covered layer; E) fermenting under drip irrigation conditions, and then sowing desert plants. In the present invention, composting technology can be well combined with a drip irrigation system, and at the same time cooperate with a water-retaining liquid mulch film, not only the waste is recycled, but also the defect of high water evaporation in the desert area is compensated, and the high temperature characteristics of the desert are used to accelerate the humification process of the compost, realizing the comprehensive management and resource utilization of organic waste, while scientifically and effectively improving the desert soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a diagram showing the germination index of the desert soil after improvement according to Example 1 of the present invention;

[0025] Figure 2 This is a pH change diagram of the simulated composting process in Example 1 of the present invention;

[0026] Figure 3 This is a comparison diagram of the desert before and after improvement by Example 1 of the present invention;

[0027] Figure 4 This is a diagram showing the germination index of the desert soil after improvement in Comparative Example 1 and Example 1 of the present invention;

[0028] Figure 5 The pH change diagram of the simulated composting process of Comparative Example 1 and Example 1 of the present invention;

[0029] Figure 6 This is a diagram showing the seed germination rate after desert soil improvement in Comparative Example 2 and Example 1 of the present invention;

[0030] Figure 7 The pH change diagram of the simulated composting process of Comparative Example 2 and Example 1 of the present invention. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The present invention provides a method for improving desert soil, comprising the following steps:

[0033] A) mixing sludge produced by municipal sewage treatment with crop waste materials to obtain a mixed material;

[0034] B) laying the mixed material under the desert surface and sealing it with sand to obtain a mixed material layer and a covering sand layer;

[0035] C) Carry out irrigation to ensure that water penetrates the sand cover and the mixed material layer;

[0036] D) uniformly applying a water-retaining liquid ground film on the surface of the sand covering layer;

[0037] E) Fermentation is carried out under drip irrigation conditions and then desert plants are sown.

[0038] Regarding step A):

[0039] The sludge generated by urban sewage treatment is mixed with crop waste materials to obtain a mixed material.

[0040] The sludge produced by the urban sewage treatment has a high nitrogen content, and the crop waste material has a high carbon content. The present invention uses these two waste components as raw materials for the mixed material.

[0041] In some embodiments of the present invention, the mass content of nitrogen in the sludge produced by the urban sewage treatment is 1% to 6%.

[0042] In some embodiments of the present invention, the mass content of carbon in the crop waste material is 35% to 50%.

[0043] In some embodiments of the present invention, the crop waste material is selected from straw. The size of the crop waste material is 1 to 3 cm. Specifically, the crop waste material can be obtained by drying, cutting and crushing the crop waste material.

[0044] In some embodiments of the present invention, the sludge produced by urban sewage treatment is mixed with crop waste materials in a dry matter mass ratio of 0.5-1.5:1-2, such as 1:1.5. The carbon-nitrogen ratio (C / N) of the mixture is 20-25:1, such as 25:1.

[0045] Regarding step B):

[0046] The mixed material is laid under the desert surface and sealed with sand to obtain a mixed material layer and a covering sand layer.

[0047] In some embodiments of the present invention, the paving method may be uniform burial using a machine.

[0048] In some embodiments of the present invention, the material is laid 15 to 35 cm below the ground surface. After laying, it is covered with sand to obtain a mixed material layer and a covered sand layer. The covered sand layer is the sand layer covering the mixed material layer.

[0049] Regarding step C):

[0050] Irrigate to ensure that water penetrates the cover sand layer and the mixed material layer.

[0051] In some embodiments of the present invention, irrigation is performed by drip irrigation, and specifically, a drip irrigation system can be used for irrigation to ensure that water penetrates the sand layer and the mixed material layer, so that the sand layer and the mixed material layer are completely soaked. The drip irrigation system is a drip irrigation belt. The drip irrigation belt is laid 8 to 12 cm below the sand layer, specifically 10 cm.

[0052] In some embodiments of the present invention, the irrigation time is 22 to 26 hours, such as 24 hours.

[0053] Regarding step D):

[0054] A water-retaining liquid mulch is evenly applied on the surface of the sand layer.

[0055] In some embodiments of the present invention, 1 to 2 hours, such as 1.5 hours, after the irrigation is completed, the water-retaining liquid mulch is uniformly applied to the surface of the sand layer to ensure that the liquid mulch is completely covered. The application method is spraying.

[0056] Regarding step E):

[0057] Fermentation is carried out under drip irrigation conditions and then desert plants are sown.

[0058] In some embodiments of the present invention, the drip irrigation time is 7 to 15 days, such as 15 days.

[0059] Seeding of desert plants specifically includes:

[0060] Next to the drip irrigation belt, desert plant seeds are sown in holes using a seeder, which requires each hole to be 5 to 7 cm apart, such as 6 cm, so that the seeds have sufficient space to germinate.

[0061] In some embodiments of the present invention, the desert plant is at least one of Leymus davidianus, Elymus ferruginosa, Oats and Sago sphaerocarpa.

[0062] In some embodiments of the present invention, before desert soil improvement is performed, the method further includes: fermenting a mixture of sludge produced by urban sewage treatment and crop waste materials in a closed container to obtain materials and extracts, and ensuring that the extracts have no side effects on seed germination before performing the desert soil improvement of the present invention.

[0063] The present invention aims to provide an innovative solution by optimizing the composting process and combining it with the actual situation in desertified areas. The desert environment has natural high-temperature exposure conditions, which can provide sustainable high temperature for the composting process, thereby achieving efficient utilization of waste biomass resources and providing technical support for desertification control.

[0064] In order to further illustrate the present invention, a method for improving desert soil provided by the present invention is described in detail below in conjunction with embodiments, but it should not be construed as limiting the scope of protection of the present invention.

[0065] Before desert soil improvement, the sludge produced by urban sewage treatment and the crop waste material are mixed and fermented in a closed container to obtain materials and extracts. After ensuring that the extracts have no side effects on seed germination, the desert soil improvement of the present invention is carried out.

[0066] Example 1

[0067] Methods for improving desert soil:

[0068] 1) The crop waste material straw is dried, cut and crushed to obtain the crop waste material straw of 1 to 3 cm;

[0069] The sludge produced by urban sewage treatment is mixed with the crop waste material straw at a dry matter mass ratio of 1:1.5 to obtain a mixed material; the carbon-nitrogen ratio (C / N) of the mixed material is 25:1.

[0070] 2) The mixed material is spread by a machine at a depth of 15 to 35 cm below the ground surface, and after the spread is completed, it is covered with sand to obtain a mixed material layer and a covering sand layer.

[0071] 3) Lay the drip tape 10 cm below the sand layer. After the drip tape is installed, drip irrigation is carried out for 24 hours to ensure that the covering sand layer and the mixed material layer are completely soaked.

[0072] 4) 1.5 hours after the drip irrigation is completed, the water-retaining liquid mulch is evenly sprayed on the surface of the sand layer to ensure that the liquid mulch is completely covered.

[0073] 5) After the drip irrigation and fermentation for another 15 days, the seeds of the desert plant (Leymus dasyphylla) were sown in holes next to the drip irrigation belt using a seeder; the seeder required that each hole be 6 cm apart to allow the seeds to have sufficient space for germination.

[0074] After the seeds are sown, the germination index is tested. The results are as follows: Figure 1 shown. Figure 1 This is a diagram of the germination index of the desert soil after improvement in Example 1 of the present invention. Figure 1It can be seen that the germination index showed a significant upward trend with the increase of time (days). From the initial stage to the 42nd day, the germination index gradually increased from a low value to a high value, showing a linear growth overall, and the growth was more significant in the later stage, and was greater than 70% around the 10th day. This shows that the compost has no significant biological toxicity and can be used for ecological restoration.

[0075] Figure 2 This is a pH change diagram of the fermentation process of simulated composting (step 5) in Example 1 of the present invention. Figure 2 It can be seen that as time changes, the pH value of the system first rises and then falls, and tends to be stable. In the first 10 days, the pH value rises rapidly and reaches a peak (about 8.0); then it begins to decline, and finally fluctuates in the range of 6.5 to 7.0. The reaction system experienced an initial stage of alkalinity enhancement, and then tended to be neutral. Due to the reaction of microbial activity, it showed dynamic regulation characteristics. The final compost product can be used for ecological restoration of alkaline soils and is beneficial to desert environmental governance.

[0076] Figure 3 The figure is a comparison of the desert before and after being improved by Example 1 of the present invention. Figure 3 The image on the left shows the excellent effect of the treatment measures in increasing surface vegetation cover and improving the soil environment. The image on the left shows the image before the improvement, with less surface cover or bare ground; the image on the right shows the image after the improvement, with a significant increase in vegetation cover, indicating a good treatment effect.

[0077] Comparative Example 1

[0078] The difference from Example 1 is:

[0079] Replacing the mixed material with sludge produced by municipal sewage treatment;

[0080] The remaining steps are carried out according to the steps of Example 1.

[0081] Figure 4 This is a diagram showing the germination index of the desert soil after improvement in Comparative Example 1 and Example 1 of the present invention. Figure 4 It can be seen that the germination index of Example 1 is significantly higher than that of Comparative Example 1. Among them, the germination index of Comparative Example 1 is about 120%, while the germination index of Example 1 reaches more than 140%, and there is a significant difference between the two (the letters a and b indicate significant differences). This shows that after the treatment of Example 1, the germination index has been significantly improved, which further illustrates that the improvement measures can effectively improve the germination ability of seeds and help improve the effect of ecological restoration.

[0082] Figure 5 The pH change diagram of the simulated composting process of Comparative Example 1 and Example 1 of the present invention. Figure 5It can be seen that the pH values ​​of Example 1 and Comparative Example 1 show certain regularity in their changes over time. In the early stage of the experiment (Day 1 and Day 3), the pH value of Example 1 was significantly higher than that of Comparative Example 1. The pH of Example 1 was close to 9, while the pH value of Comparative Example 1 was maintained between 7 and 8. As time went on (Day 7 to Day 21), the pH values ​​of the two groups gradually approached each other and remained between 7 and 8 with small fluctuations. By the 42nd day, the pH values ​​of the two groups were basically stable, both around 7. Overall, the pH value of Example 1 was significantly higher than that of Comparative Example 1 in the early stage, which may be related to the fact that the improvement measures enhanced the soil buffering capacity. Subsequently, the pH values ​​of the two groups tended to be consistent, indicating that the improvement treatment had a significant effect on soil pH regulation, laying a foundation for ecological restoration.

[0083] Comparative Example 2

[0084] The difference from Example 1 is:

[0085] The mixed material is replaced with crushed crop waste material straw (1-3 cm);

[0086] The remaining steps are carried out according to the steps of Example 1.

[0087] After the seeds are sown, the germination rate is tested. Figure 6 shown. Figure 6 This is a diagram of the seed germination rate after desert soil improvement in Comparative Example 2 and Example 1 of the present invention. Figure 6 It can be seen that the germination index of Example 1 is significantly higher than that of Comparative Example 2. Among them, the germination index of Comparative Example 2 is about 100%, while the germination index of Example 1 reaches more than 140%, and there is a significant difference between the two (the letters a and b indicate significant differences). This shows that after the treatment, the germination index of Example 1 is significantly improved, which has obvious advantages compared with the untreated Comparative Example 1. It shows that the improvement measures adopted by the present invention can significantly improve the germination conditions of seeds, promote the improvement of germination rate, and provide strong support for ecological restoration.

[0088] Figure 7 The pH change diagram of the simulated composting process of Comparative Example 2 and Example 1 of the present invention. Figure 7It can be seen that the pH value of Example 1 is significantly higher than that of Comparative Example 2 at each time point, showing a significant difference. In the early stage of the experiment (Day 1 and Day 3), the pH value of Example 1 is close to 9, while the pH value of Comparative Example 2 is relatively low, only about 6, with a significant difference. As time goes by (Day 7 to Day 15), the pH value of Example 1 gradually decreases to close to 7, and stabilizes above 7 in the later period (Day 21 to Day 42). The pH value of Comparative Example 2 changes less overall, always maintaining between 6 and 7. Overall, the pH value change trend of Example 1 is more significant and eventually stabilizes at a higher level, indicating that the improvement measures of the present invention effectively improve the pH environment of the soil, help promote seed germination and vegetation recovery, and provide effective protection for ecological restoration.

[0089] The description of the above embodiments is only used to help understand the method of the present invention and its core idea. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving desert soil, comprising the following steps: A) mixing sludge produced by municipal sewage treatment with crop waste materials to obtain a mixed material; B) laying the mixed material under the desert surface and sealing it with sand to obtain a mixed material layer and a covering sand layer; C) Carry out irrigation to ensure that water penetrates the sand cover and the mixed material layer; D) uniformly applying a water-retaining liquid ground film on the surface of the sand covering layer; E) Fermentation is carried out under drip irrigation conditions and then desert plants are sown.

2. The improved method according to claim 1, characterized in that: In step A), the carbon-nitrogen ratio of the mixed material is 20-25:

1.

3. The improved method according to claim 1, characterized in that: In step A), the crop waste material is selected from straw; the size of the crop waste material is 1 to 3 cm.

4. The improved method according to claim 1, characterized in that: In step B), the mixed material is laid 15 to 35 cm below the ground surface.

5. The improved method according to claim 1, characterized in that: In step C), irrigation is performed by drip irrigation; The drip irrigation system is a drip irrigation belt; the drip irrigation belt is laid 8 to 12 cm below the sand layer.

6. The improved method according to claim 1, characterized in that: In step C), the irrigation time is 22 to 26 hours.

7. The improved method according to claim 1, characterized in that: In step D), 1 to 2 hours after the irrigation is completed, a water-retaining liquid mulch film is uniformly applied on the surface of the sand layer.

8. The improved method according to claim 1, characterized in that: In step E), the drip irrigation time is 7 to 15 days.

9. The improved method according to claim 1, characterized in that: In step E), sowing desert plants specifically includes: Desert plant seeds are sown in holes beside the drip irrigation belt using a seeder; the seeder requires that each hole be 5 to 7 cm apart.

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