A drought resistance and water saving identification test equipment

Abstract

A drought resistance and water-saving identification test equipment, comprising an isolation pool, characterized in that: the isolation pool comprises a water inlet pipe, a water holding rod, an upper soil layer, a lower soil layer, a permeable layer and a drainage channel, wherein the water holding rod comprises a plurality of water holding rods, the plurality of water holding rods are evenly distributed in the isolation pool, each water holding rod is connected to the water inlet pipe to apply irrigation water introduced by the water inlet pipe to the upper and lower soil layers; the water holding rod comprises a mesh outer skin wrapped with a water holding material, a water holding material wrapped in the outer skin, and a mesh outer skin and a water holding material between the outer skin and the holding rod. A high polymer membrane between water materials; the water-holding material includes, by weight percentage, 50% vermiculite, 15% high polymer membrane, 5% activated carbon, 10% methyl cellulose, 10% xanthan gum, and 10% polyacrylamide; the upper soil layer is distributed from the surface to 120 cm underground, and its composition is loam: vermiculite = 11:1; the lower soil layer is composed of loam: vermiculite: black soil = 7:3:2, and the lower soil layer is distributed at a depth of less than 120 cm below the surface.

Description

Technical Field

[0001] The invention discloses a test facility for simulating agricultural drought stress environment to identify drought resistance and water conservation of crop varieties, and relates to the technical field of drought simulation identification test facilities. Background Art

[0002] At present, the sustainable development of agriculture is facing a water crisis. The problems of uneven spatial distribution of precipitation, low utilization rate and difficulty in utilization in dryland agricultural areas have led to the identification and selection of drought-resistant and water-saving crop varieties, which has become one of the important ways to solve the dilemma of ensuring food security and curbing groundwater overexploitation. For wheat crops, the traditional practices are as follows: 1. Field simulation of drought stress, that is, setting up 2-3 water treatments in the same adjacent area (Spring 0 water: no irrigation after spring until harvest; Spring 1 water: irrigation once before and after jointing after spring, 50 cubic meters of water / mu, until harvest; Spring 2 water: irrigation once during jointing and filling period after spring, a total of 100 cubic meters of water / mu, until harvest). The disadvantage of this method is that the water content is difficult to control accurately. Although it is marked as 50 cubic meters of water / mu, the area of ​​the ridges in the field is an approximate number, water leakage occurs during manual watering, and the large difference in surface flatness will lead to water accumulation. Therefore, the water content between plots is relatively different, so the simulation accuracy is the worst. 2. Establish facilities for drought water-saving identification test, select a certain plot, establish an isolation pool of a certain area, and accurately control the amount of water for each isolation pool each time, which can better achieve total water control. The disadvantages of this method are: different wheat varieties have different drought resistance and water-saving performance, and the growth period progress cannot be guaranteed to be completely consistent. Therefore, after irrigation at the same time, the efficiency of wheat materials in absorbing and holding water is not the same. In a limited space, materials with strong water absorption capacity during a certain growth period will cause limited water resources in the space to migrate to their vicinity, which may cause other materials with inconsistent development to not enjoy the same amount of water resources, reducing the accuracy of the simulation results. In addition, due to the large differences in root development of different materials, if only the above-ground parts are harvested and the roots are retained during long-term planting, the difference in soil environment in the isolation pool will continue to increase, thereby reducing the consistency of the simulated environment of subsequent tests and increasing the error of test identification. Summary of the invention

[0003] In order to solve the above-mentioned problems, the present application proposes a test facility that can further improve the accuracy of agricultural drought stress simulation. The most important feature of the test facility is that the degree of water uniformity in the simulated environment is improved by adding water-injection and water-retaining rods. By adding a certain proportion of other materials to the soil layer at a certain depth, the degree of interweaving of different growing roots in different soil layers is increased on the basis of increasing the soil water retention capacity, so as to achieve more uniform soil quality and reduce the impact on subsequent experiments.

[0004] According to one embodiment of the present invention, a drought resistance and water-saving identification test equipment is provided, comprising an isolation pool, the isolation pool comprising a water inlet pipe, a water holding rod, an upper soil layer, a lower soil layer, and a vermiculite layer of at least 2 cm between the upper and lower soil layers, wherein the water holding rod comprises a plurality of water holding rods, the plurality of water holding rods are evenly distributed in the isolation pool, each water holding rod is connected to the water inlet pipe to apply irrigation water introduced by the water inlet pipe to the upper and lower soil layers; the water holding rod comprises a wire mesh outer skin wrapping a water holding material, the water holding material wrapped in the outer skin, and a high polymer film located between the outer skin and the water holding material; the high polymer film itself has through holes, the through holes are evenly distributed on the high polymer film, and the water holding material is provided in the water holding material. The size of the through holes of the medium and high polymer membranes and the size of the mesh of the outer skin are combined to ensure that the injected water-holding material cannot flow out continuously, and the through holes of the high polymer membrane and the mesh of the outer skin are staggered to achieve a uniform water release effect; the water-holding material includes, by weight percentage: 50% vermiculite, 15% high polymer membrane, 5% activated carbon, 10% methyl cellulose, 10% xanthan gum, and 10% polyacrylamide; the upper soil layer is distributed from the surface to 120 cm underground, and the composition is loamy soil: vermiculite = 11:1; the lower soil layer is composed of loamy soil: vermiculite: black soil = 7:3:2, and the lower soil layer is distributed below the vermiculite layer.

[0005] According to another embodiment of the present invention, it further comprises a moisture sensor, which is arranged at 80 cm and 160 cm below the ground surface and is arranged around the water holding rod to accurately detect the amount of water for soil irrigation, so as to correct the water injection amount of the water holding rod.

[0006] According to another embodiment of the present invention, the outer skin is formed of a metal or resin material and is a cylindrical wire mesh body with a length of 1.8 m and a diameter of 5 cm.

[0007] According to another embodiment of the present invention, the distance between the water holding rods is 30 cm to achieve water uniformity.

[0008] According to another embodiment of the present invention, the water injection amount of the water holding rod is 50 cubic meters per mu, so that the relative moisture content of the soil reaches more than 65%.

[0009] According to another embodiment of the present invention, a permeation layer is provided at the lower part of the isolation pool for permeating irrigation water downward.

[0010] According to another embodiment of the present invention, the irrigation water that percolates downward is collected through a drainage channel to achieve the purpose of saving water resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the drought resistance and water-saving identification test equipment of the present invention. DETAILED DESCRIPTION

[0012] Figure 1The schematic diagram of the drought resistance and water-saving identification test equipment of the present invention is shown, which includes an isolation pool, the isolation pool includes a water inlet pipe 1, a water holding rod 3, an upper soil layer 4, a moisture sensor 5, a lower soil layer 6, a permeable layer 2 and a drainage channel 8. The water holding rod includes multiple water holding rods, and the multiple water holding rods are evenly distributed in the isolation pool, and each water holding rod is connected to the water inlet pipe to apply the irrigation water introduced by the water inlet pipe to the upper and lower soil layers.

[0013] The water-holding rod comprises a mesh outer skin that wraps the water-holding material, the water-holding material wrapped in the outer skin, and a high polymer film located between the outer skin and the water-holding material. The outer skin is formed of metal or resin material, preferably a cylindrical mesh body with a length of 1.8m and a diameter of 5cm. The water-holding material, calculated by weight percentage, comprises: 50% vermiculite, 15% high polymer film, 5% activated carbon, 10% methyl cellulose, 10% xanthan gum, and 10% polyacrylamide, which is crushed and blended by equipment such as a pulverizer and a blender to obtain the water-holding material, and poured into the cylindrical mesh body of the outer skin and the high polymer film. The high polymer film itself has through holes, and the through holes are evenly distributed on the high polymer film. The size of the through holes of the high polymer film combined with the size of the mesh of the outer skin can ensure that the water-holding material poured in cannot flow out continuously. The through holes of the high polymer film and the mesh of the outer skin are staggered, so that a more uniform water release effect can be achieved. The water-holding material can not only achieve the purpose of uniformly releasing irrigation water, but also prolong its service life by setting the water-holding material according to the above materials and the above proportions. It will not significantly harden over time, causing the water-holding rod to lose its activity and become ineffective. Experiments have shown that the service life of the water-holding rod of the present application can be extended by at least one year compared with other experimental materials. After the water-holding rod is made, it can be buried in the soil layer. The burial depth is required to be at least 160 cm below the surface. The distance between the water-holding rods is 30 cm to ensure that the water is uniformly distributed to the maximum extent. By setting the water-holding rod of the present invention, the water leakage phenomenon of artificial watering in the prior art is solved, and the difference in water between plots caused by the difference in surface flatness is eliminated. At the same time, because the water-holding rod goes deep into the ground, it can directly supply water to the root system, and it is evenly set, which avoids the problem that due to the different efficiency of water absorption and water holding of wheat materials, materials with strong water absorption capacity in a certain growth period in a limited space will cause the limited water resources in the space to migrate to its vicinity, resulting in other materials with inconsistent development not being able to enjoy the same amount of water resources, and greatly improves the accuracy of the simulation results.

[0014] The soil layer inside the isolation pool includes an upper soil layer 4 and a lower soil layer 6. The specific filling process is as follows: first add the lower soil layer 6 to 160cm, put the water holding rod to the soil surface, continue to add soil, and when it reaches 120cm, add a layer of vermiculite of at least 2cm, and then add the soil layer 4. In general, the density of the upper soil layer is greater than that of the lower soil layer. By accurately controlling the depth of the upper and lower soil layers and the density difference between the upper and lower soil layers, the problem of increased soil environment differences caused by residual roots is solved. Specifically, the applicant obtained the following Tables 1-4 through years of research.

[0015] Table 1 The percentage of root surface area in different soil depths during the flowering period of wheat to the total root system

[0016]

[0017] Table 2 The percentage of root volume at different soil depths during the flowering period of wheat in the total root system

[0018]

[0019]

[0020] Table 3 The percentage of root length at different soil depths during the flowering period of wheat in the total root system

[0021]

[0022] Table 4 The percentage of dry root weight in different soil depths during the flowering period of wheat in the total root system

[0023]

[0024] According to the data in Tables 1-4, we found that the surface area, length, volume and dry weight of the wheat material in the soil layer at a depth of 0-120 cm can reach more than 60% of the total root system, regardless of whether it is treated with water stress in spring 0 water or normal water treatment in spring 2-3 water. In response to this phenomenon, the applicant proposed to use soil with a higher density and stronger water holding capacity at this depth to prevent the root growth differences of wheat with different water-saving performance from being too large, which would cause the uniformity of the density of the soil layer to change from year to year. At the same time, by increasing the density of the soil layer, a certain squeezing effect is achieved for the roots of the soil layer, that is, an environment that is not conducive to root growth is created, the root distribution of the soil layer is reduced, and the influence of the residual roots of the soil layer is reduced. Specifically, the depth of the upper soil layer is 0-120 cm, and the composition of the soil layer is: loamy soil: vermiculite = 11:1.

[0025] At the same time, we also obtained Table 5 through experiments. According to Tables 1-4, we found that the surface area, length, volume and dry weight of the root system of the wheat material accounted for a small proportion (less than 40%) in the soil layer above 120 cm, but the root activity still maintained a high level, especially under the condition of large water stress in spring 0 water, the root activity also tended to increase with the increase of soil depth (Table 5). For this reason, the lower soil layer includes: loamy soil: vermiculite: black soil = 7:3:2. The soil with this proportion of composition is taken in the soil layer below 120 cm. The lower soil density is conducive to the drought-resistant and water-saving performance of drought-resistant and water-saving varieties, and is more conducive to the identification of drought-resistant and water-saving properties. At the same time, since the density of the lower soil layer is less than that of the upper soil layer, it is conducive to the growth of the root system to the lower soil layer to compensate for the root system shrinkage caused by the increase in the density of the upper soil layer.

[0026] Table 5 Root activity of wheat at different soil depths during flowering period

[0027]

[0028] A vermiculite layer of at least 2 cm between the upper soil layer and the lower soil layer is necessary, because we have found through many years of experiments that the existence of this layer is very helpful for maintaining the independence of the two soil layers and preventing environmental changes in the upper and lower soil layers when there is continuous irrigation with a water-holding rod. For soil layers without a water-holding rod, the vermiculite layer is optional, but in the case of a water-holding rod, the interactivity between the upper and lower soil layers will be greatly improved. Over time, this improved interactivity will cause the upper and lower soil layers to have a trend of changing in a consistent manner, thereby failing to achieve the purpose of setting the upper and lower soil layers. Therefore, the vermiculite layer between the upper and lower soil layers is necessary and positive and effective for the present invention.

[0029] When the water injection volume of the water holding rod is calculated as 50 cubic meters per mu, it takes 2 days to make the relative moisture content of the soil reach more than 65%, and the water can be effectively held for 10 days, decreasing at an average rate of 10% during these 10 days. The moisture sensors are set at 80cm and 160cm below the surface, around the water holding rod to accurately detect the amount of soil irrigation water, so as to correct the water injection volume of the water holding rod.

[0030] A permeation layer 2 is provided at the lower part of the isolation pool for the irrigation water to permeate downwards. The irrigation water permeating downwards is collected through a drainage channel 8 to achieve the purpose of saving water resources.

Claims

1. A drought resistance and water saving identification test equipment, comprising an isolation tank, characterized in that: The isolation pool includes a water inlet pipe, a water holding rod, an upper soil layer, a lower soil layer, and a vermiculite layer of at least 2 cm between the upper and lower soil layers, wherein the water holding rod includes a plurality of water holding rods, the plurality of water holding rods are evenly distributed in the isolation pool, and each water holding rod is connected to the water inlet pipe to apply the irrigation water introduced by the water inlet pipe to the upper and lower soil layers; the water holding rod includes a wire mesh outer skin wrapped with a water holding material, the water holding material wrapped in the outer skin, and a high polymer membrane located between the outer skin and the water holding material; the high polymer membrane itself has through holes, the through holes are evenly distributed on the high polymer membrane, wherein the size of the through holes of the high polymer membrane is similar to the mesh size of the outer skin. The sizes of the water-holding material can be combined to ensure that the injected water-holding material cannot flow out continuously, and the through holes of the high polymer membrane are staggered with the meshes of the outer skin to achieve a uniform water release effect; the water-holding material comprises, by weight percentage, 50% vermiculite, 15% high polymer membrane, 5% activated carbon, 10% methyl cellulose, 10% xanthan gum, and 10% polyacrylamide; the upper soil layer is distributed from the surface to 120 cm underground, and is composed of loamy soil: vermiculite = 11:1; the lower soil layer is composed of loamy soil: vermiculite: black soil = 7:3:2, and the lower soil layer is distributed below the vermiculite layer.

2. The drought resistance and water saving identification test equipment according to claim 1, characterized in that: It also includes moisture sensors, which are arranged at 80 cm and 160 cm below the ground surface and are arranged around the water holding rod to accurately detect the amount of soil irrigation water, so as to correct the water injection amount of the water holding rod.

3. The drought resistance and water saving identification test equipment according to claim 1, characterized in that: The outer skin is formed of metal or resin material and is a cylindrical wire mesh body with a length of 1.8 m and a diameter of 5 cm.

4. The drought resistance and water saving identification test equipment according to claim 1, characterized in that: The distance between the water holding rods is 30 cm to achieve water uniformity.

5. The drought resistance and water saving identification test equipment according to claim 1, characterized in that: The water injection amount of the water holding rod is 50 cubic meters per mu, so that the relative moisture content of the soil reaches more than 65%.

6. The drought resistance and water saving identification test equipment according to claim 1, characterized in that: An infiltration layer is provided at the bottom of the isolation pool for the irrigation water to infiltrate downwards.

7. The drought resistance and water saving identification test equipment according to claim 6, characterized in that: The irrigation water that seeps downward is collected through drainage channels to save water resources.

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