Method for determining a regional rice allowance for phosphorus fertilizer application surplus

Abstract

The application discloses a method for determining the surplus amount of phosphorus fertilizer application for regional rice, and relates to the technical field of agriculture. The method comprises the following steps: obtaining the yield increment of phosphorus fertilizer for regional rice according to field experiment data; constructing a regression relationship between the amount of applied phosphorus and the yield increment; establishing a linear relationship between the amount of applied phosphorus and the apparent balance amount of phosphorus; determining the data range of phosphorus nutrient imbalance based on the yield increment of phosphorus fertilizer for regional rice, and then obtaining the range of the amount of applied phosphorus; determining the range value of the apparent balance amount of phosphorus according to the relationship between the amount of applied phosphorus and the apparent balance amount of phosphorus in the step, and the range value is the surplus amount of phosphorus application for regional rice; and obtaining the surplus amount of phosphorus fertilizer application for regional rice after data conversion. The application can guarantee the yield of rice and maximize the saving use of phosphate rock resources, and provides a feasible measure for the intensive management of phosphorus fertilizer.

Description

Technical Field

[0001] This invention relates to the field of agricultural technology, and in particular to a method for determining the allowable surplus of phosphate fertilizer application in regional rice cultivation. Background Technology

[0002] The application of phosphate fertilizer plays a vital role in promoting rice growth and development, improving rice quality, increasing rice yield, and enhancing rice's resistance to adverse conditions. Phosphorus, as one of the essential nutrients for crop growth and development, participates in the formation of substances such as phospholipids, cell membranes, and proteins, as well as energy conversion, playing an irreplaceable role in accelerating rice tillering and increasing rice starch content.

[0003] However, there is a serious problem of excessive phosphorus application in rice-growing areas. Long-term excessive fertilizer application weakens the yield-increasing effect of fertilization on rice, and also causes problems such as low fertilizer utilization, waste of fertilizer resources, and environmental risks caused by fertilizer loss. In particular, phosphorus runoff loss in paddy fields during the alternating wet and dry periods of rice cultivation has become a significant pathway for point source and non-point source pollution. Furthermore, as a mineral resource, the non-renewable nature of phosphate fertilizer leads to continuously decreasing reserves; with the continuous mining of phosphate rock, reserves are expected to be depleted within the next 100 years. Relying on the traditional practice of applying large amounts of phosphate fertilizer to increase rice yield is unsustainable. The accumulation of phosphorus in the soil has led to a continuous decline in the yield-increasing benefits of phosphorus application for rice in some areas, and even instances where phosphate fertilizer application does not increase yield. Therefore, advocating for rational phosphorus application is crucial for increasing and stabilizing rice yields and for the sustainable development of agriculture.

[0004] Phosphate fertilizer applied to the soil is easily fixed by mineral adsorption and chemical precipitation; therefore, excessive application of phosphate fertilizer will not lead to sustained yield increases. To maintain the apparent phosphorus balance in the soil-plant system and improve phosphate fertilizer utilization, it is necessary to reduce the amount of phosphate applied to the phosphorus balance level or below. This will significantly reduce soil phosphorus accumulation and phosphorus loss in high-phosphorus soils, provided that crop yields are not reduced. Improving phosphorus use efficiency and thus reducing phosphate fertilizer input will have a significant positive impact on the global phosphorus cycle. Controlling phosphate fertilizer application to the apparent phosphorus balance level of the soil-plant system and determining the permissible surplus range of phosphate fertilizer is a crucial approach to addressing excessive phosphate fertilizer application and fixation losses, and is an essential and paramount task in phosphate fertilizer management. Determining the permissible phosphorus surplus range based on crop yield increase and phosphate fertilizer recovery rate is of great significance for increasing crop yield, promoting the economical use of phosphate fertilizer, reducing point source and non-point source pollution caused by phosphate fertilizer loss, and promoting sustainable agricultural development. Summary of the Invention

[0005] The purpose of this invention is to provide a method for determining the allowable surplus of phosphate fertilizer application in regional rice cultivation, in order to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides a method for determining the allowable surplus of phosphate fertilizer application in rice in a given region, comprising the following steps:

[0008] S1. Based on field experiment data, obtain regional data on the increase in phosphate fertilizer yield of rice, i.e., the increase in phosphate fertilizer yield;

[0009] Field experiment data requirements: The same plot should include yields from both phosphate fertilizer treatments and non-phosphate fertilizer treatments; there should be clear phosphate fertilizer application rates and rice yields; apart from the phosphate fertilizer application rate, all other measures, including planting patterns and farmland management, should be consistent.

[0010] Based on the yield of the phosphate fertilizer treatment and the yield of the non-phosphate fertilizer treatment, a quantitative relationship between the yield of the phosphate fertilizer treatment and the non-phosphate fertilizer treatment is established by formula (1): (The phosphate fertilizer treatment is the application of all nitrogen, phosphorus and potassium fertilizers, and the only difference between the non-phosphate fertilizer treatment and the phosphate fertilizer treatment is that no phosphate fertilizer is applied)

[0011] Y0 = a × Y (1)

[0012] In formula (1), Y represents the yield obtained under the application of phosphate fertilizer, which is the treatment with the highest yield among the phosphate fertilizer treatments; Y0 represents the yield of the treatment without phosphate fertilizer; a is a coefficient, representing the proportion of the yield of the treatment without phosphate fertilizer to that of the treatment with phosphate fertilizer.

[0013] The yield increase efficiency of rice after applying phosphate fertilizer can be calculated using equation (1):

[0014] Y OΔ =(1-a)×100 (2;

[0015] In equation (2), Y OΔ The percentage increase in yield is indicated by the optimized application of phosphate fertilizer.

[0016] S2. Establish the relationship between phosphorus application rate and increased phosphate fertilizer yield;

[0017] Calculate the yield increase rate under different phosphorus application rates:

[0018] Y Δ = (Y-Y0)÷Y0×100(3);

[0019] In equation (3), Y Δ Y represents the yield increase rate (%) under different phosphorus application rates, Y represents the yield with phosphate fertilizer, and Y0 represents the yield without phosphate fertilizer.

[0020] Further research can reveal the relationship between phosphorus application rate and increased phosphate fertilizer yield:

[0021] Y Δ =b×F P 2+ c×F P +d (4);

[0022] In equation (3), F P Indicates the amount of phosphorus applied; b, c, and d are coefficients;

[0023] Equation (3) can be used to calculate the increase in phosphorus yield and the corresponding amount of phosphorus applied under this increase;

[0024] Furthermore, the amount of phosphorus applied under the yield increase obtained from equations (1) and (2) can be calculated;

[0025] S3. Establish a linear relationship between the amount of phosphorus applied and the apparent balance of phosphorus; the apparent balance of phosphorus is the difference between the amount of phosphorus applied and the amount of phosphorus removed from the crop.

[0026] Phosphorus apparent balance (P Δ The calculation is as follows:

[0027] P Δ = F P - R p (5);

[0028] In equation (5), P Δ Indicates phosphorus apparent balance; F P Indicates the amount of phosphorus applied; R p This represents the amount of phosphorus removed from crops, specifically the amount of phosphorus removed from the aboveground parts of rice, which is the sum of phosphorus absorbed by the grains and straw.

[0029] Establish P Δ and F P Linear relationship between parameters;

[0030] P Δ = e×F P + f(6);

[0031] In equation (6), P Δ Indicates phosphorus apparent balance; F P This indicates the amount of phosphorus applied; e is a coefficient; f is a constant.

[0032] S4. Determine the data range for phosphorus nutrient balance based on the increase in phosphorus fertilizer yield in regional rice:

[0033] Based on the regression relationship in S2, the phosphorus application rate under the optimal yield increment in S1 is obtained. Then, based on this phosphorus application rate and the relationship in S3, the optimal apparent phosphorus balance is obtained. Since the apparent phosphorus balance is the difference between the phosphorus application rate and the amount of phosphorus removed from the crop, the amount of phosphorus removed from the crop is obtained.

[0034] The optimal PNB-P is calculated according to the following formula;

[0035] PNB-P= Rp ÷F P ;

[0036] In the formula, PNB-P represents phosphorus partial nutrient balance, and R p F represents the amount of phosphorus removed from crops. P Indicates the amount of phosphorus applied;

[0037] If the optimal PNB-P > 1.0, adjust the upper limit of PNB-P to 1.0 and the lower limit to 0.8;

[0038] If 0.8 < optimal PNB-P < 1.0, adjust the lower limit of PNB-P to 0.8, while keeping the upper limit unchanged;

[0039] If the optimal PNB-P is less than 0.8, adjust the upper limit of PNB-P to 0.8, while keeping the lower limit unchanged.

[0040] The upper limit corresponds to the minimum amount of phosphorus applied, and the lower limit corresponds to the maximum amount of phosphorus applied.

[0041] S5. Based on the data range of phosphorus partial nutrient balance determined in S4, obtain the range of phosphorus application rate according to the formula in step S4.

[0042] S6. Based on the relationship between the amount of phosphorus applied and the apparent balance of phosphorus in step S3, determine the range of the apparent balance of phosphorus, which is the allowable surplus of phosphorus application for rice in the region.

[0043] S7. Convert the regional allowable phosphorus application surplus obtained in step S6 into the amount of phosphate fertilizer used in production practice to obtain the regional allowable phosphate fertilizer application surplus.

[0044] The present invention also provides a system for determining the allowable surplus of phosphate fertilizer application in regional rice, comprising: a memory and a processor, wherein the memory stores a computer program executed by the processor, and the computer program, when executed by the processor, performs the method for determining the allowable surplus of phosphate fertilizer application in regional rice as described above.

[0045] The present invention further provides a storage medium storing a computer program, which, when running, executes the method for determining the allowable surplus of phosphate fertilizer application in rice in the aforementioned region.

[0046] The present invention discloses the following technical effects:

[0047] This invention proposes a method for determining the allowable surplus of phosphate fertilizer application in regional rice fields, in order to solve the problem of unscientific application of phosphate fertilizer in existing fertilization methods. While ensuring rice yield, it maximizes the economical utilization of phosphate rock resources and provides feasible measures for intensive management of phosphate fertilizer. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a graph illustrating the relationship between phosphorus application and rice yield increase in Example 1 of the present invention.

[0050] Figure 2 This is a graph used in Embodiment 1 of the present invention to determine the relationship between phosphorus application rate and yield increase in rice.

[0051] Figure 3 This is a diagram showing the relationship between phosphorus application rate and apparent phosphorus balance in rice, as used in Example 1 of the present invention. Detailed Implementation

[0052] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0053] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0054] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0055] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0056] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0057] Rice is widely cultivated in various regions, with diverse planting types. This invention categorizes rice data into four parts based on planting type: early rice, mid-season rice, late rice, and single-season rice, and provides related implementation examples. Early and late rice are mainly grown in southern China, with an early-late rice rotation system; mid-season rice is mainly found in the Yangtze River basin, with a wheat-mid-season rice or rapeseed-mid-season rice rotation system; and single-season rice is mainly found in northeastern China, with a one-crop-per-year system.

[0058] Example 1

[0059] (1) Collect and summarize field trial data of early rice, mid-season rice, late rice, and single-season rice in the study area, including:

[0060] All experimental data came from field trials, including trials of different phosphate fertilizer application rates, the 3414 trial, and trials of recommended phosphate fertilizer application rates. The experimental data included the amount of phosphate fertilizer applied, rice yield, and phosphorus uptake in the treatments with and without phosphate fertilizer.

[0061] The yield-increasing effect of phosphate fertilizer application on rice under different planting types was calculated. Among them, the treatment with the highest yield from full application of nitrogen, phosphorus and potassium fertilizers was used to optimize the fertilizer yield.

[0062] Linear simulations were used to model the relationship between the yields of early-season rice, mid-season rice, late-season rice, and single-season rice under full nitrogen, phosphorus, and potassium application and the yields without phosphorus application (e.g., ...). Figure 1 ),in:

[0063] Early rice: y = 0.866x;

[0064] Medium-grain rice: y = 0.902x;

[0065] Late-season rice: y = 0.895x;

[0066] Single-season rice: y = 0.871x;

[0067] In this formula, x is the rice yield when nitrogen, phosphorus, and potassium fertilizers are applied in full, and y is the rice yield when no phosphorus fertilizer is applied.

[0068] Furthermore, the optimal phosphate fertilizer yield-increasing effect was calculated, where:

[0069] Early rice = (1 - 0.866) × 100 = 13.4%;

[0070] Medium-grain rice = (1 - 0.902) × 100 = 9.8%;

[0071] Late-season rice = (1 - 0.895) × 100 = 10.5%;

[0072] One-season rice = (1 - 0.871) × 100 = 12.9%;

[0073] (2) A quadratic curve model was used to simulate the relationship between phosphorus application rate and yield increase for rice of different planting types (e.g., Figure 2 ),in:

[0074] This section of data includes the phosphorus application rate and the corresponding yield increment, and the relationship is as follows:

[0075] Early rice: y = -0.0115x 2 + 0.9255x + 0.3683;

[0076] Medium-grain rice: y = -0.0044x 2 + 0.4655x + 0.3624;

[0077] Late-season rice: y = -0.0088x 2 + 0.6298x + 1.0826;

[0078] Single-season rice: y = -0.0084x 2 + 0.8438x + 0.1214;

[0079] In this formula, y represents the yield increase after applying phosphate fertilizer, and x represents the amount of phosphate applied.

[0080] Furthermore, the amount of phosphorus applied under the optimal yield increment obtained in step (1) can be obtained, where

[0081] Early rice: 18.2 kg P / ha;

[0082] Medium-grain rice: 27.4 kg P / ha;

[0083] Late-season rice: 21.3 kg P / ha;

[0084] Single-season rice: 18.6 kg P / ha;

[0085] (3) A linear relationship was used to simulate the relationship between the amount of phosphorus applied and the apparent balance of phosphorus, wherein:

[0086] The apparent balance of phosphorus is the difference between the amount of phosphorus applied and the amount of phosphorus removed, where:

[0087] Nutrient removal is based on the phosphorus accumulation in the aboveground parts. Straw has low phosphorus content, low mineralization in the current season, and low availability. Therefore, straw nutrients are classified as nutrient removal.

[0088] The relationship between phosphorus application rate and apparent phosphorus balance is as follows: Figure 3 ,in:

[0089] Early rice: y = 0.9045x - 26.829;

[0090] Medium-grain rice: y = 0.9069x - 27.018;

[0091] Late-season rice: y = 0.8242x - 27.172;

[0092] Single-season rice: y = 0.8118x - 30.547;

[0093] In this formula, y represents the apparent balance of phosphorus, and x represents the amount of phosphorus applied.

[0094] Furthermore, the apparent phosphorus balance at the highest yield increment obtained in step (1) can be obtained, wherein:

[0095] Early rice: -10.4 kg P / ha;

[0096] Medium-grain rice: -2.2 kg P / ha;

[0097] Late rice: -9.6 kg P / ha;

[0098] Single-season rice: -15.4 kg P / ha;

[0099] (4) The rationality of the phosphorus application rate obtained in step (2) is judged based on the phosphorus partial nutrient balance (PNB-P). First, the amount of phosphorus removed is calculated. The calculation formula is: the difference between the amount of phosphorus applied and the amount of phosphorus nutrient balance, where:

[0100] The apparent phosphorus balance of early-season rice, mid-season rice, late-season rice, and single-season rice are all negative. Therefore, the amount of phosphorus removed is:

[0101] Early rice: 18.2 + 10.4 = 28.6 kg P / ha;

[0102] Medium-grain rice: 27.4 + 2.2 = 29.6 kg P / ha;

[0103] Late-season rice: 21.3 + 9.6 = 30.9 kg P / ha;

[0104] Single-season rice: 18.6 + 15.4 = 34.0 kg P / ha;

[0105] Furthermore, the PNB-P of early rice, mid-season rice, late rice, and single-season rice under the yield increment in step (1) can be obtained, wherein:

[0106] Early rice: 28.6 ÷ 18.2 = 1.57;

[0107] Medium-grain rice: 29.6 ÷ 27.4 = 1.08;

[0108] Late-season rice: 30.9 ÷ 21.3 = 1.45;

[0109] Single-season rice: 34.0 ÷ 18.6 = 1.83;

[0110] (5) Adjust the phosphorus application rate based on the PNB value. Since the PNB-P of early rice, mid-season rice, late rice, and single-season rice is all >1.0, the upper limit of PNB-P is adjusted to 1.0, which corresponds to the lower limit of phosphorus application rate, i.e., the amount of phosphorus removed.

[0111] Early rice: 28.6 kg P / ha;

[0112] Medium-grain rice: 29.6 kg P / ha;

[0113] Late-season rice: 30.9 kg P / ha;

[0114] Single-season rice: 34.0 kg P / ha;

[0115] Furthermore, the upper limit of phosphorus application for early rice, mid-season rice, late rice, and single-season rice is determined, and the lower limit of PNB-P is set to 0.8, that is, the amount of phosphorus removed is 80% of the phosphorus application amount. At this time, the phosphorus surplus (apparent phosphorus balance) is equivalent to 0.2 times the phosphorus application amount (i.e., 1-0.8=0.2). The corresponding phosphorus application amount is calculated according to the formula in step (3), where:

[0116] Early rice: 26.829 ÷ (0.9045 - 0.2) = 38.1 kg P / ha;

[0117] Medium-grain rice: 27.018 ÷ (0.9069 - 0.2) = 38.2 kg P / ha;

[0118] Late-season rice: 27.172 ÷ (0.8242 - 0.2) = 43.5 kg P / ha;

[0119] Single-season rice: 30.547 ÷ (0.8118 - 0.2) = 49.9 kg P / ha;

[0120] Furthermore, the optimal phosphorus fertilizer utilization range can be derived, specifically the phosphorus application rate range for early, mid, late, and single-season rice when PNB-P is between 0.8 and 1.0.

[0121] Early rice: 28.6-38.1 kg P / ha;

[0122] Medium-season rice: 29.6-38.2 kg P / ha;

[0123] Late rice: 30.9-43.5 kg P / ha;

[0124] Single-season rice: 34.0-49.9 kg P / ha;

[0125] (6) Based on the phosphorus application range obtained in step (5), and according to the formula in step (3), the allowable phosphorus surplus under the optimized phosphorus fertilizer utilization range, i.e., when the PNB-P of early rice, mid-season rice, late rice, and single-season rice are all between 0.80 and 1.00, can be obtained, where:

[0126] Early rice: 0-7.6 kg P / ha;

[0127] Medium-grain rice: 0-7.6 kg P / ha;

[0128] Late-season rice: 0-8.7 kg P / ha;

[0129] Single-season rice: 0-10.0 kg P / ha;

[0130] Furthermore, converting this range of phosphorus usage to actual usage in production practice—that is, converting elemental phosphorus to oxides—and multiplying by a coefficient of 2.292, the allowable surplus of phosphate fertilizer application is:

[0131] Early rice: 0-17.5 kg P2O5 / ha;

[0132] Medium-season rice: 0-17.5 kg P2O5 / ha;

[0133] Late-season rice: 0-19.9 kg P2O5 / ha;

[0134] Single-season rice: 0-22.8 kg P2O5 / ha;

[0135] In major rice-producing areas, including early-season, mid-season, late-season, and single-season rice, two scenarios—customary fertilization and optimized fertilization—were set up to verify the rationality of the phosphate fertilizer surplus range, using conventional fertilization as a control. This included rice yield, phosphorus application rate, phosphorus uptake, and PNB-P under different fertilization scenarios.

[0136] Table 1

[0137]

[0138] Table 1 shows the effects of different fertilization scenarios on phosphorus application rate, yield, phosphorus uptake, and PNB-P for early-season, mid-season, late-season, and single-season rice. Field trial results indicate that the conventional fertilization method resulted in a significant excess of phosphorus, leading to PNB-P values ​​of only 0.71, 0.63, 0.68, and 0.74 for early-season, mid-season, late-season, and single-season rice, respectively, all below the calculated lower limit of 0.8. The low PNB-P values ​​under conventional fertilization indicate a substantial phosphorus surplus, with surpluses reaching 23.0, 36.3, 26.5, and 26.7 kg P2O5 / ha for early-season, mid-season, late-season, and single-season rice, respectively. These phosphorus surpluses all exceeded the upper limit of allowable surpluses, exceeding it by 5.5, 18.8, 6.6, and 3.9 kg P2O5 / ha, respectively. Optimized fertilization showed that, compared with conventional fertilization, phosphorus application was reduced by 11.5%, 25.7%, 25.9%, and 21.4% in early-season rice, mid-season rice, late-season rice, and single-season rice, respectively; rice yield increased by 9.7%, 3.9%, 8.0%, and 5.2%, respectively; and phosphorus uptake increased by 6.4%, 6.5%, 5.5%, and 3.7%, respectively. Optimized fertilization significantly improved phosphorus fertilizer utilization efficiency, with PNB-P ratios reaching 0.84, 0.91, 0.98, and 0.98 for early-season rice, mid-season rice, late-season rice, and single-season rice, respectively. The phosphorus surplus in all four rice planting types was within the allowable phosphorus surplus range.

[0139] The rational application of phosphate fertilizer plays a crucial role in rice cultivation. Phosphorus, an indispensable nutrient element for rice growth, not only promotes root development but also enhances the rice's resistance to adverse conditions, increasing yield and quality. Rational application of phosphate fertilizer can significantly increase the number of effective panicles per unit area, the grain filling rate, and the thousand-grain weight, thereby increasing yield and improving rice quality. Due to its low water solubility and low volatility, phosphorus is often adsorbed and deposited in the soil as mineral salts. This phosphorus is easily lost during rice production, leading to eutrophication of water bodies. Optimized phosphate application can significantly reduce phosphate fertilizer loss. With increased phosphate fertilizer application, phosphorus loss also increases significantly, especially during rainfall and irrigation. Optimized phosphate application can reduce phosphate fertilizer application while ensuring rice yield, thereby reducing phosphorus loss and protecting the environment. Excessive phosphate application in rice cultivation is extremely common. Therefore, it is crucial to manage phosphate fertilizer based on the crop's yield response—that is, the yield-increasing efficiency after phosphate fertilizer application—while ensuring crop yield. While ensuring that the increase in yield does not decrease, it provides rice growers and agricultural decision-makers with a better range of phosphorus application, which helps to make phosphorus resources more efficient.

[0140] Developing a reasonable range for phosphorus application based on different rice cultivation types is of great significance for improving phosphorus utilization, protecting the ecological environment, and conserving resources. Scientific phosphorus application methods can improve phosphate fertilizer utilization, reduce resource waste, lower production costs, and increase economic benefits. Therefore, establishing a permissible phosphorus surplus range for rice has a significant impact on the environmental benefits of optimized phosphorus application in rice cultivation. It can protect the ecological environment by reducing phosphorus loss and environmental pollution, while simultaneously improving phosphate fertilizer utilization efficiency, which is of great practical significance.

[0141] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for determining a permissible excess amount of phosphorus fertilizer application for a region of rice, characterized by, Comprising the following steps: S1. Obtain regional rice phosphorus fertilizer yield increment data, i.e. yield increment of phosphorus fertilizer, according to field experiment data; Field experiment data requirements: the same plot contains phosphorus fertilizer treatment and no phosphorus fertilizer treatment yield; There is a clear amount of phosphorus fertilizer and rice yield; Except for the amount of phosphorus fertilizer, other measures including planting mode, farmland management measures are consistent; According to the yield of phosphorus fertilizer treatment and the yield of no phosphorus fertilizer treatment, the quantitative relationship between the yield of phosphorus fertilizer and the yield of no phosphorus fertilizer is established by formula (1): the phosphorus fertilizer treatment is the full use of nitrogen, phosphorus and potassium fertilizer, and the only difference between the no phosphorus fertilizer treatment and the phosphorus fertilizer treatment is that no phosphorus fertilizer is used; Y0=a×Y (1); In formula (1), Y represents the yield obtained under the application of phosphorus fertilizer, and Y represents the yield obtained under the application of phosphorus fertilizer; Y0 represents the yield of no phosphorus treatment; a is a coefficient, which represents the proportion of no phosphorus yield to phosphorus treatment; The yield increment efficiency of rice after applying phosphorus fertilizer is calculated by formula (1): Y OΔ = (1 - a) x 100 (2); In formula (2), Y OΔ represents the yield increase rate (%) under the optimized application of phosphorus fertilizer; S2. Construct the relationship between the amount of phosphorus and the yield increment of phosphorus fertilizer; Calculate the yield increment rate under different amounts of phosphorus: Y Δ = (Y-Y0)÷Y0x100 (3); In formula (3), Y Δ represents the yield increase rate (%) under different phosphorus application amounts, Y represents the yield with phosphorus application, and Y0 represents the yield without phosphorus application; Further obtain the relationship between the amount of phosphorus and the yield increment of phosphorus fertilizer: Y Δ = b x F P 2 + c x F P + d (4); In formula (4), F P represents the amount of phosphorus applied; b, c, d are coefficients; Calculate the yield increment of phosphorus and the corresponding amount of phosphorus under this increment by formula (4); Further calculate the amount of phosphorus under the yield increment rate obtained by formula (1) and formula (2); S3. Establish the linear relationship between the amount of phosphorus and the apparent balance of phosphorus; the apparent balance of phosphorus is the difference between the amount of phosphorus and the amount of phosphorus removed by crops; Phosphorus apparent equilibrium (P Δ ) was calculated as: P Δ = F P - R p (5); In formula (5), P Δ represents phosphorus apparent balance; F P represents phosphorus application amount; R p represents crop phosphorus removal amount, which is the phosphorus removal amount of rice aboveground part, and is the sum of phosphorus absorbed by grains and straws; Establishment of P Δ and F P linear relationship between parameters; P Δ = e×F P + f(6); In formula (6), P Δ represents the apparent equilibrium of phosphorus; F P represents the amount of phosphorus applied; e is a coefficient; and f is a constant. S4. Determine the data range of phosphorus partial nutrient balance based on the yield increment of regional rice phosphorus fertilizer: According to the regression relationship in S2, the amount of phosphorus under the best yield increment of S1 is obtained, and then according to the relationship of S3, the best apparent balance of phosphorus is obtained; according to the difference between the amount of phosphorus and the amount of phosphorus removed by crops, the amount of phosphorus removed by crops is obtained; The best PNB-P is calculated according to the following formula: PNB-P = R p ÷F P ; where PNB-P represents phosphorus nutrient balance, R p represents crop phosphorus removal, F P represents phosphorus application rate; If the best PNB-P>1.0, adjust the upper limit of PNB-P to 1.0, and the lower limit to 0.8; If 0.8<best PNB-P<1.0, adjust the lower limit of PNB-P to 0.8, and the upper limit remains unchanged; If the best PNB-P<0.8, adjust the upper limit of PNB-P to 0.8, and the lower limit remains unchanged; Wherein, the upper limit corresponds to the minimum amount of phosphorus, and the lower limit corresponds to the maximum amount of phosphorus; S5. According to the amount of phosphorus obtained by formula in step S4, the range of the amount of phosphorus is obtained according to step S4; S6. According to the relationship between the amount of phosphorus and the apparent balance of phosphorus in step S3, the range value of the apparent balance of phosphorus is determined, which is the allowed phosphorus application surplus of regional rice; S7. Convert the allowed phosphorus application surplus of regional rice obtained in step S6 into the amount of phosphorus fertilizer in production practice to obtain the allowed phosphorus fertilizer application surplus of regional rice.

2. A system for determining a regional rice allowable phosphorus fertilizer application surplus amount, characterized by, Comprising: Memory and processor, the memory has computer program run by the processor stored thereon, the computer program runs the method for determining the allowed phosphorus fertilizer application surplus of regional rice as claimed in claim 1 when the processor is run.

3. A storage medium, characterized by The storage medium has stored thereon a computer program which, when executed, performs the method of determining the allowable phosphorus fertilizer application surplus amount of a region of rice.

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