CN113307700A

CN113307700A - Humic acid-containing organic-inorganic compound fertilizer special for rice

Info

Publication number: CN113307700A
Application number: CN202110764904.1A
Authority: CN
Inventors: 王峰; 马军伟; 林辉; 俞巧钢; 孙万春; 王强; 叶静
Original assignee: Zhejiang Academy of Agricultural Sciences
Current assignee: Zhejiang Academy of Agricultural Sciences
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2021-08-27
Anticipated expiration: 2041-07-07
Also published as: CN113307700B

Abstract

The invention belongs to the field of compound fertilizers required in agricultural production, and particularly relates to a humic acid-containing organic-inorganic compound fertilizer special for rice. It includes: nitrogen fertilizer, phosphate fertilizer, potash fertilizer, secondary element fertilizer, trace element fertilizer and humic acid; the content of humic acid is more than or equal to 20 wt%; the nitrogen fertilizer consists of an organic nitrogen fertilizer and an inorganic nitrogen fertilizer, wherein the mass ratio of the organic nitrogen fertilizer to the inorganic nitrogen fertilizer is 1 (0.1-0.2); the organic nitrogen fertilizer comprises cooked soybeans, wherein the cooked soybeans account for 5-10 wt% of the total mass of the compound fertilizer; the secondary element fertilizer is a silicon fertilizer; the weight ratio of the citrate soluble silicon fertilizer to the water soluble silicon fertilizer is 1 (0.1-0.15), and the silica accounts for 50-60 wt% of the total weight of the silicon fertilizer; the microelement fertilizer is soluble zinc salt. The invention can obviously improve the nutrient utilization rate of the rice crops on the compound fertilizer and realize effective utilization of the biomass.

Description

Humic acid-containing organic-inorganic compound fertilizer special for rice

Technical Field

The invention belongs to the field of compound fertilizers required in agricultural production, and particularly relates to a humic acid-containing organic-inorganic compound fertilizer special for rice.

Background

China is a big agricultural country and has great demand on agricultural products and fertilizers required in the agricultural production process. The compound fertilizer is a common fertilizer, generally refers to a chemical fertilizer containing two or more nutrient elements, has the advantages of high nutrient content, few side ingredients, good physical properties and the like, and plays an important role in balancing fertilization, improving the utilization rate of the fertilizer and promoting high and stable yield of crops. However, it has some disadvantages, such as that its nutrient proportion is always fixed, and the kinds, amounts and proportions of nutrient elements required for different soils and different crops are various.

However, the utilization rate of the compound fertilizer is low at present. In rice planting, after the compound fertilizer containing nitrogen, phosphorus and potassium elements is applied, the minimum utilization rate of nitrogen, phosphorus and potassium nutrients can even be as low as 10 percent, great material waste is generated, and the problems of large amount of rice nutrition unbalance, soil nutrient loss and the like are caused.

In this regard, those skilled in the art have developed specialized fertilizers for different crops. For rice, CN103910567B is an organic-inorganic compound fertilizer special for rice. According to the technical scheme, the rice fertilizer is scientifically proportioned according to the requirement of the rice on nitrogen, phosphorus and potassium so as to improve the utilization rate of the fertilizer of the rice and realize the yield increase of 10-20%.

However, in practice, tests show that the actual nutrient utilization rate of the fertilizer is still relatively limited, especially the utilization rate of the potassium fertilizer is relatively low, and further improvement space exists.

Disclosure of Invention

The invention provides a special organic-inorganic compound fertilizer containing humic acid for paddy rice, which aims to solve the problems that the nutrient utilization rate of the existing compound fertilizer is low, a large amount of nutrients cannot be effectively utilized, soil acidification is possibly caused, soil nutrient loss is caused and the like.

The invention aims to:

firstly, the nutrient utilization rate of the rice on the special compound fertilizer is improved;

secondly, improving the nutrient content of the soil and realizing soil fattening;

thirdly, for the rice, the obvious rice yield increase can be realized;

compared with other conventional fertilizers, the fertilizer application amount can be effectively reduced, soil acidification is effectively relieved, the soil environment is improved, and the effects of energy conservation and environmental protection are achieved.

In order to achieve the purpose, the invention adopts the following technical scheme.

An organic-inorganic compound fertilizer containing humic acid specially used for paddy rice,

the method comprises the following steps:

nitrogen fertilizer, phosphate fertilizer, potash fertilizer, secondary element fertilizer, trace element fertilizer and humic acid;

the content of humic acid is more than or equal to 20 wt%;

the compound fertilizer contains the following effective components in percentage by mass:

6-10 wt% of nitrogen, 2.5-4.5 wt% of phosphorus pentoxide, 3.5-5.5 wt% of potassium oxide and 0.2-0.6 wt% of zinc;

the nitrogen fertilizer consists of an organic nitrogen fertilizer and an inorganic nitrogen fertilizer, wherein the mass ratio of the organic nitrogen fertilizer to the inorganic nitrogen fertilizer is 1 (0.1-0.2);

the organic nitrogen fertilizer comprises cooked soybeans, wherein the cooked soybeans account for 5-10 wt% of the total mass of the compound fertilizer;

the secondary element fertilizer is a silicon fertilizer, and the silicon fertilizer comprises a citrate soluble silicon fertilizer, a water soluble silicon fertilizer and silica;

the weight ratio of the citrate soluble silicon fertilizer to the water soluble silicon fertilizer is 1 (0.1-0.15), and the silica accounts for 50-60 wt% of the total weight of the silicon fertilizer;

the microelement fertilizer is soluble zinc salt.

The nitrogen fertilizer, the phosphate fertilizer and the potassium fertilizer are mainly used for providing nitrogen, phosphorus and potassium elements required by rice growth, wherein the optimal mass ratio of nitrogen, phosphorus and potassium is 15:6:8, namely the mass ratio of nitrogen, phosphorus pentoxide and potassium oxide. However, if the above-mentioned nutrient ratio is simply realized, the absorption and utilization rate of nutrients in actual rice is not good, and even soil acidification is caused, so that it is necessary to apply silicon fertilizer in combination. Silicon is an extremely important nutrient element of plants, a large number of crops have extremely high absorption rate to silicon, even higher than the absorption rate to three nutrients of nitrogen, phosphorus and potassium, and the application of silicon fertilizer is also beneficial to improving the photosynthesis capability and the insect disease resistance capability of the crops and has obvious effect of improving soil. In the invention, the citrate soluble silicon fertilizer and the water soluble silicon fertilizer are matched to realize the long-acting slow release of silicon so as to meet the requirement of crops on silicon, and the addition of the silica can also effectively improve the colony environment of soil and the absorption and utilization rate of the crops on phosphorus and potassium, improve the nutrient utilization rate of the crops on compound fertilizers and correct the acidity of the soil.

Meanwhile, humic acid can enhance the absorption of rice crops to nitrogen nutrients and improve the absorption utilization rate of the crops to nitrogen elements.

The humic acid can obviously improve the carbon content of the compound fertilizer, simultaneously provide nitrogen, hydrogen and sulfur, improve the organic nutrients of soil, increase the porosity of the compound fertilizer and improve the respiratory environment of the root of crops after fertilization. The trace element fertilizer can make up for the defect of insufficient trace elements in the conventional compound fertilizer.

As a preference, the first and second liquid crystal compositions are,

the organic nitrogen fertilizer also comprises organic matters obtained by composting fermentation;

the inorganic nitrogen fertilizer includes, but is not limited to, urea or ammonium chloride or mono-or di-ammonium phosphate.

The inorganic nitrogen fertilizers are common and easy to obtain, and the using effect of the urea is practically optimal in the technical scheme of the invention. Therefore, researches show that under the composite action of humic acid and silicon fertilizer, urea can realize efficient conversion, improve the efficiency and effect of nitrogen release, and remarkably improve the utilization rate of the rice crops on nitrogen nutrients. The organic matter for the compost fermentation includes but is not limited to common bean cakes, straw powder, peanut shells and the like. During the composting fermentation process, a starter with the weight of about 0.5-1 per mill of the dry organic matter is added. 1 per mill of leaven is added in the composting fermentation process.

As a preference, the first and second liquid crystal compositions are,

the phosphate fertilizer includes but is not limited to calcium magnesium phosphate fertilizer or calcium superphosphate or magnesium superphosphate or monoammonium phosphate or diammonium phosphate.

The phosphate fertilizers are all the common phosphate fertilizers which are easy to obtain and are easy to be absorbed by rice crops.

As a preference, the first and second liquid crystal compositions are,

the potash fertilizer includes, but is not limited to, potassium sulfate or potassium chloride.

The potassium fertilizers are all the types of commonly available potassium fertilizers which are easily absorbed by rice crops.

As a preference, the first and second liquid crystal compositions are,

the particle size of silica in the silicon fertilizer is more than or equal to 2.0 mm and the silica is subjected to alcohol washing treatment;

the alcohol washing treatment comprises the following steps: the silica is physically dispersed in an anhydrous alcohol solution for 5-10 min.

The method has the advantages that the silica with larger particle size is selected, particularly the silica with the particle size of 2-4 mm is selected, larger pore space can be generated, the respiratory environment of the rice crops after fertilization is improved, the air permeability of the roots of the rice crops is improved, phosphorus and potassium elements in soil can be effectively activated, the content of available phosphorus and available potassium in soil nutrients is improved, the acid-base environment of the soil is improved under the matching action of humic acid, and the absorption utilization rate of the crops on nitrogen, phosphorus and potassium nutrients, particularly phosphorus and potassium nutrients is greatly improved. Meanwhile, through the physical dispersion treatment of the anhydrous alcohol solution, the water absorption of the silica can be effectively inhibited, and the problem that the silica generates soil water robbery is avoided.

As a preference, the first and second liquid crystal compositions are,

the microelement fertilizer is zinc sulfate.

Zinc sulfate is a common, easily available and readily absorbable trace element fertilizer for rice crops.

As a preference, the first and second liquid crystal compositions are,

the compound fertilizer also contains a water-retaining fertilizer-preserving agent;

the water and fertilizer retention agent comprises:

water retention agent and fertilizer retention agent for inhibiting nutrient decomposition.

The addition and use of the water and fertilizer retention agent can effectively improve the stability of the nutrient content of the soil for a long time. The water-retaining agent can effectively realize the adjustment of the soil water environment to be uniform. The fertilizer retention agent has the main effect of inhibiting nutrients released by the compound fertilizer in the soil or the decomposition and the loss of the nutrients fixed by the soil under natural conditions, so that the nutrients cannot be effectively utilized.

As a preference, the first and second liquid crystal compositions are,

the water-retaining agent is silicon dioxide powder;

the mesh number of the silicon dioxide powder is more than or equal to 200 meshes, and the silicon dioxide powder is subjected to anhydrous alcohol dispersion treatment;

the fertilizer retention agent is NBPT and/or DMPP;

the water and fertilizer retention agent contains 4.0-5.5 wt% of NBPT and 3.5-5.0 wt% of DMPP.

The silicon dioxide powder mainly plays a role in balancing the soil water environment through the characteristic of high porosity, and the problem that the actual water retention capacity is weakened due to the strong soft agglomeration effect of high-number silicon dioxide obtained by grinding can be effectively avoided through anhydrous alcohol dispersion treatment. On the other hand, abundant hydroxyl on the surface of the silicon dioxide can capture and adsorb humic acid, and loss of decomposition products is reduced. And the fertilizer retention agents NBPT (n-butyl thiophosphoryl triamide) and DMPP (3, 4-dimethyl-pyrazole phosphate) can effectively inhibit the decomposition and loss of organic nitrogen in soil, and improve the effective utilization rate of nitrogen nutrients and the long-acting retention effect. Normally, the high-nitrogen content compound fertilizer is not suitable for NBPT and DMPP because the problem of soil acidification is easily caused, but the invention can effectively inhibit the problem after being matched with silicon fertilizer.

As a preference, the first and second liquid crystal compositions are,

the content of the water and fertilizer retention agent in the compound fertilizer is 2.0-3.0 wt%.

If the dosage of the water and fertilizer retention agent is too much, the actual nutrient release is easy to slow, and if the dosage is too little, the good water and fertilizer retention effect can not be realized.

The invention has the beneficial effects that:

1) compared with the existing compound fertilizer special for rice, the compound fertilizer disclosed by the invention can adapt to the requirements of nitrogen, phosphorus and potassium nutrients of rice, and the nutrient utilization rate of rice crops on the compound fertilizer is obviously improved;

2) the nutrient content in the soil can be kept stable for a long time, and good soil fattening and long-acting slow release effects are realized;

3) the yield of rice crops can be obviously improved, and the nutritive value of actual grains can be improved;

4) the fertilizing amount can be reduced by more than 15%, the acidified soil environment is improved, and the energy is saved and the environment is protected;

5) the biomass is effectively utilized.

Detailed Description

The present invention will be described in further detail with reference to specific examples. Those skilled in the art will be able to implement the invention based on these teachings. Moreover, the embodiments of the present invention described in the following description are generally only some embodiments of the present invention, and not all embodiments. Therefore, all other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort shall fall within the protection scope of the present invention.

Unless otherwise specified, the raw materials used in the examples of the present invention are all commercially available or available to those skilled in the art; unless otherwise specified, the methods used in the examples of the present invention are all those known to those skilled in the art.

The irrigation of the invention is carried out by adopting a conventional dry-wet alternative irrigation mode: and (4) controlling the water to be irrigated for 1-2 cm when the water potential of the soil naturally falls to-15 kPa from the shallow water layer, and circulating.

Example 1

the composition is shown in table 1 below.

TABLE 1 composition of Compound fertilizers of example 1

In the fertilizer of the embodiment, silica is placed in absolute ethyl alcohol for ultrasonic dispersion for 10 min, and the fine powder of the mixed yellow phosphorus slag and sodium metasilicate are leached out to obtain a medium element fertilizer; and (3) placing the 200-mesh silicon dioxide fine powder into absolute ethyl alcohol, performing ultrasonic dispersion for 30 min, then leaching out, mixing with NBPT and DMPP, and drying at 45 ℃ for 1 h to obtain the water and fertilizer retention agent.

The total amount of the fertilizer prepared was 200 kg. Through detection and analysis, the fertilizer prepared in the embodiment has the nitrogen content of 8.8 wt%, the phosphorus pentoxide content of 3.5 wt%, the potassium oxide content of 4.7 wt% and the zinc content of 0.4 wt%.

The fertilizer produced in this example was labeled as S1.

Example 2

the composition is shown in table 2 below.

TABLE 2 composition of Compound fertilizers of example 2

The total amount of the fertilizer prepared was 200 kg. Through detection and analysis, the fertilizer prepared in the embodiment has the nitrogen content of 6.2 wt%, the phosphorus pentoxide content of 2.6 wt%, the potassium oxide content of 3.5 wt% and the zinc content of 0.2 wt%.

The fertilizer produced in this example was labeled as S2.

Example 3

the composition is shown in table 3 below.

TABLE 3 composition of Compound fertilizers of example 3

The total amount of the fertilizer prepared was 200 kg. Through detection and analysis, the fertilizer prepared in the embodiment has the nitrogen content of 9.9 wt%, the phosphorus pentoxide content of 4.3 wt%, the potassium oxide content of 5.5 wt% and the zinc content of 0.6 wt%.

The fertilizer produced in this example was labeled as S3.

Comparative example 1

The specific compound fertilizer components are the same as in example 1, except that:

the humic acid is not added, urea and straw with equal mass are used for replacing the humic acid, and the nitrogen content is still about 8.8 percent by calculation.

The fertilizer produced in this comparative example was labeled D1.

Comparative example 2

the straw substitute is not added with silicon fertilizer and silica, and is replaced by straw with equal mass.

The fertilizer produced in this comparative example was labeled D2.

Comparative example 3

no water and fertilizer retention agent is added, and straws with equal mass are used for replacing the straws.

The fertilizer produced in this comparative example was D3.

Comparative example 4

In the conventional compound fertilizer, the proportion of nitrogen, phosphorus and potassium (nitrogen element, phosphorus pentoxide and potassium oxide) in the compound fertilizer is 15:6:8, the content of the nitrogen, phosphorus pentoxide and potassium oxide is basically the same as that in the embodiment 1, and the content difference of the nitrogen, phosphorus pentoxide and potassium oxide is less than or equal to 0.3 wt%.

The fertilizer produced in this comparative example was D4.

Testing

The above examples 1 to 3 and comparative examples 1 to 4 were tested.

Setting up a Rice planting testAnd (4) a zone. The area of the test zone was 30 m²Sowing in 26 days in 4 and 15 months in 2019, and transplanting in 15 days in 5 and 5 months in 2019. The following test groups were set, and the fertilization amounts and fertilization patterns of the respective test sections were as shown in the following table.

In the mature period of the rice, 5 clusters of rice with uniform growth vigor are randomly adopted in each test group, and are placed at 105 ℃ for de-enzyming for 30 min and then are dried to constant weight at 75 ℃. Grinding the straw and the seeds through a 0.25 mm sieve, and digesting the straw and the seeds by a concentrated sulfuric acid-hydrogen peroxide method. The nitrogen, phosphorus and potassium of the plants are respectively measured by a distillation method, a molybdenum blue colorimetric method and a flame photometric method.

After the rice is mature, 5 soil samples are randomly collected from each test group, uniformly mixed and sampled according to a quartering method. And after the soil sample is collected, air-drying and sieving the soil sample for measuring the physical and chemical properties. The soil organic matter is oxidized by potassium dichromate-sulfuric acid. The soil total nitrogen and the alkaline hydrolysis nitrogen are respectively measured by a half-trace Kjeldahl nitrogen determination method and a sodium hydroxide despreading method. Available phosphorus is produced by using hydrochloric acid-ammonium fluoride according to the following ratio: liquid =1:10 ratio colorimetric determination after leaching. Quick-acting potassium utilization rate of 1 mol ∙ L^-1Ammonium acetate was prepared as soil: liquid =1:10 ratio was measured by flame photometry after leaching.

Data processing and statistical analysis were performed using Microsoft Excel 2010 and SPSS 13.0, multiple comparisons and differential significance detection were performed using Duncan new complex polarization method (P < 0.05), and a graph was prepared using SigmaPlot 10.0.

Firstly, soil nutrients are detected and analyzed. The measurement results are shown in the following table.

TABLE 4 soil nutrient test table.

As is apparent from the data in Table 4 above, the fertilizer of the present invention can significantly improve soil fertility. Moreover, the soil acidity can be corrected very effectively. The data of the blank control group, namely the original soil, after the fertilizer disclosed by the invention is applied, the pH value gradually tends to be neutral, so that the acidity of the soil is obviously weakened. On the other hand, the contents of organic carbon and total nitrogen in the soil are obviously improved, and the contents of alkaline hydrolysis nitrogen, available phosphorus, quick-acting potassium and the like which are convenient for rice crops to absorb are also obviously improved. Comparing SD4 and SD5, it can be seen that humic acid is a key parameter affecting soil total nitrogen and alkaline hydrolysis nitrogen, and on the premise that the nitrogen content is maintained by replacing humic acid with other nitrogen sources, the total nitrogen and alkaline hydrolysis nitrogen in soil are both reduced remarkably, and the reduction range is increased along with the increase of fertilizer dosage. This is probably due to the disruption of the synergistic balance of humic acid and silicon fertilizer.

Also, compared with the SD6 test group, it is obvious that in the case of reducing the silicon fertilizer, compared with the SD4 test group and the SD1 test group, the content of organic carbon is increased, the content of available phosphorus and available potassium is basically equal, but the content of total nitrogen and alkaline-hydrolyzed nitrogen is further reduced, and the correction effect of soil acidity is weakened.

It is shown that in practice, at least the humic acid and the silicon fertilizer should be present and added to the fertilizer in the appropriate proportions to produce a good synergistic effect.

The SD7 test group shows that the soil nutrient loss is serious, especially the organic carbon loss is severe under the condition of not adding a water and fertilizer retention agent.

The SD8 test group did not actually produce crops effectively because the crops produced severe seedling burning after early fertilization.

The SD9 test group is that the conventional fertilizer is applied in a mode of base application and additional fertilizer matching, the crop growth is normal and accords with the expectation, the soil is acidified to a certain extent, the actual soil fattening effect is poor, and the alkaline hydrolysis nitrogen content and the effective phosphorus content are both reduced obviously.

The rice yield data was further calculated. Some rice yield data are shown in table 5 below.

TABLE 5 Rice yield data.

As is apparent from Table 5 above, the yield of rice was significantly reduced in the case of using other nitrogen sources in place of humic acid. The main decline lies in that the effective ear number of the rice is obviously reduced, and the thousand-grain weight is obviously reduced. The humic acid in the scheme of the invention plays an important role in improving the effective spike and thousand-grain weight of rice. Compared with the SD4 test group, the SD5 test group increases the application amount of the fertilizer, the actual yield is further reduced, and the effective spike and thousand-grain weight content is further reduced. By combining SD6 test group data, it can be seen that the actual silicon fertilizer and humic acid have an important synergistic effect, and the period without applying humic acid or silicon fertilizer has a more obvious influence on the rice yield in the aspect of effective spike and thousand-grain weight.

Further observing the SD7 test group data, it can be seen that, under the condition of not adding water and fertilizer retention agent, the fructification rate and thousand kernel weight are obviously reduced, which shows that the effective ear and ear number are not obviously affected, and the actual effect is the late growth of the crops, and the effect on the growth in the early and middle stages is weak.

Compared with the existing fertilizer, the fertilizer disclosed by the invention can obviously optimize the rice yield data in all aspects. However, the reason for this is that it is also expected that the yield of rice is significantly adversely affected in the case where the actual amount of applied conventional fertilizer should reach 110 kg/a and the applied fertilizer amount is reduced by about 16%.

Namely, the fertilizer actually produces good energy conservation and environmental protection.

In addition, the potassium content of rice grains is detected. The results are shown in Table 6 below.

Test group	SD1	SD4	SD5	SD6	SD7	SD9
							Grain potassium content/%)	0.261	0.247	0.240	0.231	0.254	0.222

As is evident from the data in table 6 above, the potassium content of the grain increased by about 18% compared to conventional fertilizers. Research shows that the application of green manure and chemical fertilizer has obvious regulation and control effect on the nutrition of rice grains. Potassium in grains is a very important nutrient index, but potassium is usually enriched in straws, so that the potassium content in the grains is generally lower than 0.23%, and the potassium content in the grains is in a positive correlation with the crude protein content in the grains, so that the potassium in the grains of the rice crops is improved, and the nutritive value of the rice grains is obviously improved. Therefore, the special fertilizer containing humic acid for rice can effectively improve the nutritive value of rice.

Besides soil nutrients and actual rice yield, actual soil microorganisms and soil enzyme activities are also important soil quality indexes. Wherein, the soil respiration intensity is selected as a microbiological index mainly reflecting the soil quality, and urease, acid phosphatase and dehydrogenase are selected as enzymatic activity indexes reflecting the soil quality.

Measuring soil respiration intensity by adopting indoor closed culture and caustic soda absorption with the concentration of 0.1M; measuring urease activity in soil by adopting a sodium phenolate colorimetric method; measuring the activity of the soil acid phosphatase by adopting a disodium phenyl phosphate colorimetric method; the dehydrogenase activity was determined by TTC colorimetry.

The measurement structure is shown in table 7 below.

TABLE 7 soil microbial activity and enzyme activity test data sheet.

From the table 7 above, it is firstly very intuitive and obvious that under the action of the fertilizer of the present invention, the soil environmental stress degree can be significantly reduced, the increase of the soil respiration intensity after fertilization is generally recognized as a stress response of microorganisms, meanwhile, the soil respiration intensity and the soil metabolic entropy are in positive correlation, and the actual change trends of the two have similar change trends under the condition that the content of the microorganism C is basically unchanged. However, actual tests show that the change trend of the soil microorganism amount C is opposite to the trend in the table, so that the actual soil metabolic entropy is almost in square positive correlation with the soil respiration intensity in the table 7, namely the soil metabolic entropy of SD5 is obviously higher than that of SD1, the soil metabolic entropy of the SD6 test group is much higher than that of the SD1 test group, and the increase of the soil metabolic entropy shows that the soil microorganisms need more energy, which indicates that the soil microorganisms actually have certain adverse effects on the soil microorganisms.

The soil enzyme activity obviously shows that under the action of the special fertilizer containing humic acid for rice, the activity of various enzymes in soil, especially urease and dehydrogenase, can be obviously improved. Studies have shown that the activities of urease and dehydrogenase are positively correlated with the chlorophyll content, proline content and peroxidase activity of rice, and can effectively improve the quality of rice, while acid phosphatase has a positive promoting effect on the chlorophyll content of rice, but is negatively correlated with the proline content and peroxidase activity of rice, and therefore needs to be inhibited to some extent. Whereas the urease activity and dehydrogenase activity of the SD1 test group were relatively highest, and the acid phosphatase was almost lowest, compared to the conventional fertilizer and the remaining test groups.

Therefore, the quality of rice can be improved very effectively by adjusting the activity of the enzyme in the soil to be suitable for rice.

Claims

1. An organic-inorganic compound fertilizer containing humic acid special for paddy rice, which is characterized in that,

the method comprises the following steps:

the content of humic acid is more than or equal to 20 wt%;

the microelement fertilizer is soluble zinc salt.

2. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

the inorganic nitrogen fertilizer comprises urea or ammonium chloride or monoammonium phosphate or diammonium phosphate.

3. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

the phosphate fertilizer comprises calcium magnesium phosphate fertilizer or calcium superphosphate or magnesium superphosphate or monoammonium phosphate or diammonium phosphate.

4. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

the potash fertilizer is potassium sulfate or potassium chloride.

5. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

6. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

the microelement fertilizer is zinc sulfate.

7. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 1,

the water and fertilizer retention agent comprises:

8. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 7,

the water-retaining agent is silicon dioxide powder;

the fertilizer retention agent is NBPT and/or DMPP;

9. The organic-inorganic compound fertilizer containing humic acid special for paddy rice as claimed in claim 7 or 8,