Method for preventing and controlling rooted weeds in saline-alkali cultivated land through straw composting fermentation heat

Abstract

The invention relates to a method for preventing and treating rooted weeds in saline-alkali cultivated land by utilizing straw composting fermentation heat. The method comprises crop straws and ingredients thereof, a galvanized aluminum plate, an iron component, a composting film, a circulating air pump and a PVC (Polyvinyl Chloride) pipe. One end of the iron component is fixed at the prefabricated position of the galvanized aluminum plate, and the other end is inserted underground. After the galvanized aluminum plates are arranged, a layer of geotechnical cloth is laid below the whole compost heap, crop straw and ingredients thereof are stacked to a certain thickness, a plurality of PVC pipes which are communicated with one another are inserted into the compost heap, one end of each PVC pipe is sealed, and the other end of each PVC pipe is connected with a circulating air pump to realize aeration so as to create aerobic fermentation conditions. Heat in the fermentation process is transferred to the lower layer of the soil through a galvanized aluminum plate and an iron component, the temperature of the soil can be increased by about 20 DEG C by 0-30 cm, the soil temperature reaches 45-55 DEG C in summer and is maintained for 7-8 days, the germination rate of weed propagules in the soil of the saline-alkali cultivated land can be effectively reduced, and root weeds can be prevented and controlled. By means of the method, germination of root weed propagules in 0-30 cm soil can be effectively reduced, the environmental burden of root weed control is relieved, and the problem that root weeds in saline-alkali cultivated land are difficult to control is solved to a certain extent. Meanwhile, straw fermentation heat is fully utilized, and comprehensive utilization of agricultural solid waste straw is achieved. The method has important significance on green and efficient prevention and control of root weeds in saline-alkali cultivated land soil and agricultural sustainable development.

Description

Technical Field

[0001] The invention relates to the field of agriculture, and in particular to a method for preventing and controlling rooted weeds in saline-alkali farmland by utilizing heat from straw composting and fermentation. Background Art

[0002] Due to its special ecological conditions, saline-alkali farmland is generally home to a variety of weeds, some of which, such as reeds ( Phragmites australis (Cav.) Trin. ex Steud), Cupressus Calystegia hederacea Wall.), bitter herbs ( Ixeris chinensis (Thunb.) Nakai) and other root weeds reproduce asexually using underground rhizomes or runners as reproductive bodies. These root weeds usually have strong ecological adaptability, well-developed root systems, and rapid growth and reproduction. These characteristics make it difficult to control root weeds in saline-alkali farmland. In addition, the presence of these root weeds will occupy crop growth space, affect the normal growth of crops, and thus affect yields, which will have an adverse impact on agricultural production.

[0003] According to the existing technical means, in agricultural production, weeds in farmland are mostly eliminated through physical or chemical measures. For example, the invention patent "A weeding device for agricultural crop planting and its method (CN118489408A)" mentions that a motor is used to drive the cutting blade to mechanically crush the weed plant body, and the "a weeding device for corn planting (CN221329569U)" uses a mowing motor combined with a cutting blade to achieve physical weeding and mowing synchronous operation; the invention patent "a composite herbicide and its preparation method (CN118765909A)" mentions that ammonia fluroxypyr and diuron are added to the organic solvent to achieve the purpose of efficient weeding. And the "a herbicide composition containing benzaclodomyr, clofopyralid and atrazine (CN103141487A)" invented a method of using a combination of benzaclodomyr, clofopyralid and atrazine to eliminate grass weeds. Based on this, most of the existing invention patents act on the above-ground part of farmland weeds after germination, and the goal is to remove weeds. There are few invention patents that act on the underground reproductive bodies before weeds germinate and are aimed at preventing and controlling weeds in saline-alkali farmland. Therefore, it is necessary to explore an efficient and low-cost method for pre-emptive prevention and control of rooted weeds in saline-alkali farmland before they germinate.

[0004] In recent years, as agricultural solid waste, the comprehensive utilization of straw has been increasingly valued, and composting is an important utilization method. During the composting process, the biomass energy stored in the straw is released and converted into a large amount of heat energy, which increases the temperature inside the compost pile. The temperature inside the compost pile can reach 60-70°C and last for 8-10 days. However, the purpose of traditional composting is mainly to obtain its fermentation products, and the utilization of these heat energies is less. In the existing materials, only a few invention patents have utilized this heat energy. For example, in the invention patent "A device and method for farmers to use straw fermentation piles to generate heat for heating (CN112210478A)", it is mentioned that heat can be collected by composting and heat exchange systems for indoor heating of farmers, and "A device and method for sustainable heat extraction from a composting system (CN112097312A)" also mentions that the fermentation heat can be collected by laying pipes under the compost pile for heating. However, the heat generated by this type of invention patent is mostly used for heating or to provide suitable temperature conditions for its ancillary processing. There are few cases of using the heat from straw fermentation to create a heat stress environment for weed control in saline-alkali farmland.

[0005] Using the heat generated by straw fermentation for weed control in saline-alkali farmland is a new method for weed control. This will reduce the cost of controlling root weeds in saline-alkali farmland and improve the control efficiency while realizing the comprehensive utilization of agricultural solid waste straw. It is of great significance to ensure the normal growth of crops in saline-alkali land, agricultural production and sustainable development of agriculture. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art and the current status of straw utilization, the present invention proposes a method for preventing and controlling root weeds in saline-alkali farmland by utilizing the heat of straw composting and fermentation, the main target of which is reed ( Phragmites australis (Cav.) Trin. ex Steud), Cupressus Calystegia hederacea Wall.), bitter herbs ( Ixeris chinensis (Thunb.) Nakai) and other root weeds that grow in saline-alkali farmland and reproduce asexually with underground rhizomes or runners as reproductive bodies. The temperature in the straw aerobic compost pile can reach 60-70℃ for 8-10 days, while raising the temperature of the cultivated soil to 45-55℃ for 7-8 days in summer. This temperature is enough to create a high temperature stress environment and inhibit the growth of underground reproductive bodies of root weeds in saline-alkali farmland. This method can achieve green, efficient and low-cost prevention and control of root weeds in saline-alkali farmland, and can effectively control the regrowth of root weeds.

[0007] In order to solve the aforementioned technical problems, the present invention adopts the following technical scheme: a method for preventing and controlling rooted weeds in saline-alkali farmland by utilizing heat fermentation of straw compost, comprising crop straw and its ingredients, galvanized aluminum sheet, iron component, compost film, geotextile, circulating air pump, PVC pipe, one end of the iron component is inserted into the ground, and the other end is fixed to the prefabricated position of the galvanized aluminum sheet with a thread. In specific implementation, the galvanized aluminum sheet component is inserted into the soil (30 cm) with the iron component as the medium, and after laying a layer of geotextile under the entire fertilizer pile, the straw and its ingredients are piled up in a square and circular pattern to a certain thickness, and the top is tightly covered with a compost film. Insert a plurality of PVC branch pipes with holes at a suitable height in the middle of the fertilizer pile, and all the branch pipes are connected side by side to a main pipe, which is externally connected to a circulating air pump.

[0008] Preferably, the galvanized aluminum sheet has a size of 100cm*100cm and a thickness of 5mm.

[0009] Preferably, the galvanized aluminum plate has 6 evenly spaced internal threaded holes with a major diameter of 60 mm and a length of 5 mm along two diagonal lines.

[0010] Preferably, the iron component has a length of 30 cm, an outer diameter of 60 mm, is solid, has an outer thread with a major diameter of 60 mm and a length of 5 mm at one end, and is sharpened by 5 cm at the other end for easy insertion into the ground.

[0011] Preferably, the inner diameter of the PVC branch pipe is 60 mm, the inner diameter of the main pipe is 90 mm, one end of the branch pipe is blocked, and 5 circular holes with a diameter of 30 mm are evenly opened on both sides.

[0012] Preferably, the average stacking thickness of the crop straw is 100 cm or more, and the stacking shape is a regular perfect circle.

[0013] Preferably, the upper and lower parts of the PVC pipe should be covered with 30 cm thick straw and should not directly contact the galvanized aluminum plate and the compost film.

[0014] Preferably, the composting film is black in color and made of polyethylene.

[0015] Compared with the existing weed control technology, the present invention has the following advantages: first, it efficiently utilizes the heat of straw compost to treat root weeds before they germinate, thereby achieving efficient, low-cost and thorough control of root weeds in farmland. Secondly, the present invention also solves the problem of difficult treatment of agricultural solid waste after crop harvest.

[0016] The present invention provides a method for efficiently utilizing heat from straw composting and fermentation to create a high temperature stress environment, and destroying the underground propagules of rooted weeds in saline-alkali farmland before they germinate. The method utilizes various types of crop straw for aerobic composting, and the high temperature generated after composting is first conducted through a galvanized aluminum plate, and then secondarily conducted through an iron component inserted into the soil. The heat is sufficient to create a high temperature stress environment in which most weed propagules cannot survive, and completely destroys the underground propagules of rooted weeds, thereby achieving fundamental prevention and control of rooted weeds and ensuring agricultural production. In addition, by utilizing straw composting, high-quality compost products are obtained, and the problem of difficult straw handling in the agricultural production process is also solved, which is of great significance to the sustainable development of agriculture. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 is a front view of the composting device; Figure 3 Plan view of galvanized aluminum sheet members; Figure 4 Sectional view of galvanized aluminum sheet member; Figure 5 It is a schematic diagram of an iron structure; Figure 6 Schematic diagram of the dynamic changes in soil temperature at a depth of 30 cm during composting. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0019] like Figure 1 The method for preventing and controlling root weeds by utilizing heat from straw composting is shown, and includes a PE composting film 1, composting straw 2, a PVC branch pipe 3, a galvanized aluminum plate 4, a main pipe 5, a circulating fan 6, and an iron component 7. The PE composting film 1 covers the top of the compost pile, a plurality of PVC branch pipes 3 are connected in parallel, one end is sealed, and the other end is connected to the circulating fan 6, the galvanized aluminum plate 4 is laid flat on the soil surface, a layer of geotextile 9 is laid under the entire compost pile, and the iron component 7 is inserted into the soil after one end is sharpened and the other end is connected to the galvanized aluminum plate 4 by threading.

[0020] like Figure 5 The iron component shown has specific specifications of a length of 30 cm, an outer diameter of 60 mm, solid, an outer thread 10 with a large diameter of 60 mm and a length of 5 mm at one end, and a 5 cm sharpened end 8 at the other end.

[0021] Galvanized aluminum sheet: Figure 3As shown, the galvanized aluminum plate is a 50cm*50cm square galvanized aluminum plate with a thickness of 5mm. The galvanized aluminum plate is a regular square and needs to have 6 internal thread holes with a maximum diameter of 60mm and a length of 5mm along its two diagonals, for a total of 12 holes.

[0022] Galvanized aluminum sheet components: its cross-section is as follows Figure 4 As shown, according to 15*10m 2 The method requires 15 galvanized aluminum plate components in total. In actual application, the number can be increased or decreased according to the composting area. The component can be composed of 13 components, including 12 Figure 5 The iron components shown and 1 Figure 3 Galvanized aluminum sheet shown. Figure 5 The iron component shown in the figure has an external thread of 5 mm in length and 60 mm in major diameter at its non-tip. Figure 3 The 12 prefabricated threaded holes in the galvanized aluminum plate can be quickly fixed as shown. Figure 4 The bottom surface shown is inserted into the soil, and the top surface is located between the soil and the straw.

[0023] Aeration device: Figure 1 It is mainly composed of components 3, 5, and 6, with a size of 15*10m 2 According to the calculation of the composting area, the aeration device is composed of a 5000W circulating air pump 6, a 15m main pipe 5 with an inner diameter of 90mm, and five 10m branch pipes 3 with an inner diameter of 60mm. One end of the branch pipe is blocked, and 30mm diameter round holes are evenly opened on both sides. The other ends of the five branch pipes are connected to the main pipe in parallel with a tee fitting every 3 meters. The main pipe is finally connected to the air pump to realize the air circulation inside the compost and increase the flow of heat therein.

[0024] The whole device forms a complete composting heating and fermentation heat collection and conduction system. In practical application, the area is 15*10m 2 For example, the compost with a thickness of 1m and a composting time of 40 days is taken as an example. The best composting time is to compost after uniform plowing in the field. Before composting, three soil temperature sensors should be placed 30cm below the compost pile to monitor the soil temperature. At the same time, multiple galvanized aluminum plate splicing parts should be connected at a rate of 10m. 2 / , evenly arranged in the pre-composting plot, the galvanized aluminum plate components are flat on the soil surface, and the iron components are fully inserted into the soil with their tips. After the galvanized aluminum plate components are arranged, a layer of geotextile is laid at the bottom of the entire compost pile to prevent the fermentation liquid from seeping in. Figure 2As shown, the straw and its ingredients are piled on the geotextile in a regular square circle with a pile thickness of 50 cm. After the pile is completed, the aeration pipe is arranged above the straw. That is, in practical applications, the aeration pipe should be located in the middle of the composting material. At the same time, a temperature sensor is arranged in it to measure the fermentation temperature. After completion, the straw is piled again until the target pile thickness is reached. After the pile is completed, the top of the straw is covered with a black impermeable and airtight polyethylene composting film. After completion, pay attention to monitor the temperature sensor reading, and turn on the circulating air pump to continuously provide an aerobic environment for continuous high-temperature fermentation. The ventilation rate is 0.26L·min -1 kg -1 Dry matter is carried out.

[0025] Taking the principle type and specifications used in the conventional arrangement of manure piles as an example, the fermentation heat that may be collected and its impact on soil temperature are calculated from a theoretical perspective. This calculation takes the arrangement of a 15m*10m*1m manure pile and 3000kg corn straw as an example, and the heat generated by the ingredients is not considered for the time being.

[0026] 1. Calculation formula and relevant data acquisition: 1) Calculate the total heat output using the formula Q 总 = m·q , where Q 总 is the total heat generated by straw combustion (J); m is the mass of straw (kg); q is the calorific value of straw (J / g), taking its lower calorific value as 17377J / g; 2) Calculate the heat generated by composting. Since the straw is not completely burned during the composting process, according to relevant literature, the total heat generated during the composting process is 40%-60% of the combustion heat. The value used in this calculation is 40%, that is, Q 堆肥 =40%Q 总 .

[0027] 3) Calculate the heat that can be effectively utilized. According to literature records, the heat lost during composting due to ventilation and oxygen supply, top heat diffusion, and water volatilization is about 50%-60% of the heat generated by the compost. In this experiment, the value is 60% of the heat lost, that is, Q 有效 =Q 堆肥 ×(1-60%).

[0028] 4) Calculate the portion transferred into the soil, and 20% of the remaining heat is transferred into the soil.

[0029] 5) Calculate soil mass using the formula m 土壤 =γ· V , m is soil mass (kg), γ is soil bulk density, which is 1.2 g / cm 3 , V is the volume of soil covered by the compost, the soil depth is 30cm, and the length and width are the size of the compost pile 15m*10m.

[0030] 6) Calculate soil temperature rise: ΔT = Q 总· m -1 土壤· c -1 土壤 , where ΔT is the temperature rise of the soil (°C), Q 总 is the total heat released by straw combustion, m 土壤 is the mass of the soil, c 土壤 The specific heat capacity of soil is 1.2 J / (g·℃).

[0031] 2. Calculation of theoretical soil temperature rise: 1) Total calories of straw: Q 总 =m 秸秆 ·q 秸秆 =17377 J / g × 3 × 10 6 g = 5.2131 × 10 10 J; 2) Heat generated by straw composting: Q 堆肥 =40% Q 总 × = 5.2131 × 10 10 J × 0.50 = 2.08524 × 10 10 J; 3) Effective use of heat: Q 有效= Q 堆肥 × (1-60%)=2.08524 × 10 10 J × 0.4 = 8.34096 × 10 9 J; 4) Actual heat transferred into the soil: Q 土壤= 20% Q 有效 =8.34096× 10 9 J × 0.20 = 1.668192 × 10 9 5) Volume of heated soil: V 土壤 =15m × 10m × 0.3m = 45m 3 ; 6) Mass of heated soil: m 土壤 =γ 土壤 × V 土壤 = 1.2 × 10 3 kg / m 3 ×45m 3 = 5.4 × 10 7 g; 7) Calculate soil temperature rise: ΔT = Q 土壤 / (m 土壤 × C 土壤) = 8.34096× 10 9 J / (5.4 × 10 7 g × 1.2 J / g·℃) = 25.74 ℃ This data is based on the low calorific value of corn straw, which is 17377 J / g. The composting heat accounts for 40% of the combustion heat, 60% of the heat is lost during the composting process, and the remaining effective heat is transferred to the soil at a rate of 20%. Theoretically, 3000 kg of straw can raise the minimum temperature of 15m*10m*0.3m soil by 25.74℃. In field applications, the amount of straw stacking can be increased or the stacking area can be reduced according to actual conditions to obtain higher heat.

[0032] The present invention generates a large amount of heat energy through straw composting, and uses a galvanized aluminum plate close to the soil surface and an iron component inserted into the soil to improve the heat conduction efficiency, so that the heat is transmitted to the soil to the greatest extent, forming a high temperature stress environment, and destroying the propagules of rooted weeds in the soil. This method makes full use of the compost fermentation heat, solves the problem of difficulty in preventing and controlling rooted weeds in farmland to a certain extent, and also realizes the comprehensive utilization of agricultural solid waste straw. It is of great significance to ensure agricultural production and sustainable development of agriculture, and has strong promotion and application value.

[0033] The implementation area is located in the Yellow River Delta Agricultural High-tech Industrial Demonstration Zone in Dongying City. It is located in the mid-latitude warm temperate zone and slightly saline-alkali land. There are many root weeds such as reeds and goosegrass in the farmland. The experiment was arranged in summer. A 15*10m 2 For plots of land, before the composting device, the soil at a depth of 30 cm was heated to 50 m 2 Three soil temperature sensors (-25-100℃) are buried at a density of / to monitor the changes in soil temperature after straw fermentation.

[0034] When arranging the composting device, first connect the galvanized aluminum plate to the iron structure through threads. After completion, the galvanized aluminum plate is connected to the iron structure with a length of 10m. 2 / pieces are evenly inserted into the plot, and a total of 10 galvanized aluminum sheet components are inserted into the plot. After the galvanized aluminum sheet components are arranged, corn stalks are collected from the farmland and piled up in the 15*10m 2 In the plot, the stacking shape is a regular square circle, and the thickness of the first layer is 50cm. After the first layer is stacked, 5 PVC branch pipes (10m long, 60mm outer diameter) with 5 30mm round holes evenly opened on both sides are arranged side by side above this layer of straw to increase the ventilation volume. One end of these 5 branch pipes is blocked and the other end is connected to the main pipe (15m long, 90mm outer diameter) with a tee. After completion, the PVC main pipe (15m long, 90mm outer diameter) is connected to the circulating air pump.

[0035] After the aeration pipeline is arranged, a temperature sensor (-25-200℃) is arranged to monitor the internal temperature of the compost. Straw is piled up on the top until the thickness reaches 1 meter. Finally, a black polyethylene compost film is covered and compacted with soil to ensure airtightness. After the entire device is arranged, the air pump is turned on, and the ventilation rate is calculated at 0.26L·min-1·kg-1 dry matter to provide aerobic fermentation of straw and continuously generate heat.

[0036] The control effect is evaluated by the ground temperature change data and the germination data of propagules in the soil during the implementation of this method: 1. Geothermal data acquisition: 1) Select three sample points near the target plot, use a ground thermometer to measure the soil temperature at 0-30cm, calculate the average value and record it as T1, which is used as the basic soil temperature data before composting. During the composting process, a temperature sensor pre-buried 30cm below the compost pile is used to monitor the soil temperature changes at the beginning of straw fermentation.

[0037] 2. Data on germination of propagules in soil: 1) Select test plots: Select 6 typical plots in the target plot, with a size of 30cm*30cm.

[0038] 2) Cultivation germination test: Before composting (I) and after composting (II), take three soil samples of 10cm*10cm*15cm (length*width*soil depth) in the selected sample plots, remove large impurities and place them in germination boxes, and cultivate them in a 25℃ constant temperature incubator with guaranteed water supply. Regularly observe and record the number, type and biomass of newly grown weeds in the soil.

[0039] 3) By comparing the germination of weeds in the soil before composting (I) and after composting (II) through germination tests, the control effect of the present invention on root weeds can be intuitively demonstrated.

[0040] The above is only a preferred embodiment of the present invention. Therefore, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preventing and controlling root weeds in saline-alkali farmland by utilizing heat from straw composting and fermentation, characterized in that: It includes crop straw and ingredients, galvanized aluminum plates, iron components, compost membranes, geotextiles, circulating air pumps, and PVC pipes; one end of the iron component is fixed to the prefabricated position of the galvanized aluminum plate, and the other end is inserted into the ground; the PVC pipes are connected side by side to a main pipe, which is finally connected to the circulating air pump.

2. The method according to claim 1, characterized in that: The main target is reeds growing in saline-alkali farmland ( Phragmites australis (Cav.)Trin. ex Steud)、Cerithidea edulis( Calystegia hederacea Wall.), bitter herbs ( Ixeris chinensis (Thunb.) Nakai) and other root weeds that reproduce asexually using underground rhizomes or runners as reproductive bodies.

3. The method according to claim 1, characterized in that: The galvanized aluminum sheet is 5mm thick and has a size of 100cm*100cm.

4. The device according to claim 3, characterized in that: The square galvanized aluminum plate has 6 internal threaded holes with a diameter of 60 mm evenly arranged along two diagonals.

5. The device according to claim 1, characterized in that: The galvanized aluminum plate is composed of 12 splicing parts, one end of the iron component is fixed in the prefabricated threaded hole of the galvanized aluminum plate with a thread, and the other end is sharpened and inserted into the soil.

6. The method according to claim 1, characterized in that: The straw used is crushed according to the fermentation requirements, and the stacking thickness is 100 cm or more, and the stacking area is a regular square circle.

7. The method according to claim 1, characterized in that: By laying galvanized aluminum plates at the bottom of the compost and inserting iron components (30 cm long) into the soil, the thermal conductivity of metal is fully utilized to enhance the heat conduction process to the underground, improve the heat conduction efficiency of fermentation heat to the soil, achieve high temperature stress on the underground reproductive bodies of rooted weeds, destroy their activity, and reduce the germination rate and germination ability of the reproductive bodies.

8. The method according to claim 1, characterized in that: By increasing the fermentation days and the heat stress time, the underground reproductive bodies of rooted weeds in saline-alkali farmland can be effectively destroyed. In saline-alkali farmland where rooted weeds occur on a large scale, continuous cross-composting can be used to achieve uninterrupted and efficient prevention and control of the underground reproductive bodies of rooted weeds.

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