CN107466516B - Method for improving deep soil of old orchard tree - Google Patents

Abstract

The method for improving the deep soil of old trees in orchards includes the following steps: (1) planning: planning drill holes with scattered distribution points, the drill holes are located inside the vertical projection of the tree crown, and the distance from the trunk of the old tree is not less than 80cm; ( 2) Drilling: Use a drill bit with a diameter of 15-20cm, and drill a hole with a depth of 50-80cm according to the planned position. When the drill bit is lifted, all the soil in the hole will be taken out, and then inserted and drilled into the hole quickly. The matching fertilization cylinder can prevent the inner wall of the drilling hole from collapsing and affecting the drilling depth; (3) Fertilization: according to the needs of soil improvement, apply pre-mixed formula fertilizer, pull out the fertilizing cylinder after fertilization, and fill the drilling hole. Using a drill bit with a diameter of 15-20cm is the optimal diameter to ensure the maximum fertilization amount and the minimum damage to the roots of the 40-80cm drilling hole; the drilling hole is light to damage the roots of large trees, and the fertilization depth is deep and adjustable. Using this feature, according to the deep soil According to the sampling analysis, there are steps to fertilize the soil, restore the soil ecological environment, and adjust the soil pH value year by year.

Description

Deep soil improvement methods for old trees in orchards

technical field

The invention belongs to the field of agriculture, and specifically relates to a deep soil improvement technology in an old tree in an orchard, in particular to transforming and repairing the deep soil environment in the canopy of an orchard without destroying the normal growth environment of the old tree, so as to achieve the effect of rejuvenation of the old tree.

Background technique

In order to obtain high yield and good economic benefits in fruit tree production, fruit farmers will fertilize fruit trees according to different growing seasons, tree ages and yields. Traditional fertilization methods include furrow application, hole application, spreading application and flushing application with water. Most of the fertilization depth is 0-20cm (surface) soil, and a small part of fertilizer depth can reach 20-40cm (subsurface) soil. However, due to the poor mobility of phosphate fertilizer and some trace elements in the soil, the shallow depth of fertilization determines the shallow depth of root absorption. When fruit tree seedlings are planted in new soil, soil nutrients are rich in organic matter, medium and trace elements, and the soil environment has good soil aggregate structure, strong air permeability, and stable microbial colonies, laying the foundation for the vigorous growth of fruit tree saplings. According to the survey of 5-year-old fruit trees The root depth can reach more than 2 meters. In the early stage of fruit trees, the yield is fast, the fruit size is large and uniform, and the fruit quality is excellent, all thanks to the high-quality soil.

With the growth of fruit trees, the increase in yield, and the more and more serious the connection between the canopies, the growth range of fruit trees above and below ground can only grow within the range of plant-to-row spacing. In order to ensure stable and high yield, it is only necessary to increase the use of chemical fertilizers. The characteristics of traditional fertilization methods are: 1. There is more damage to the roots during fertilization; 2. The depth of fertilization is 0-30cm, and the soil below 30cm can obtain fertilizer only by the gradient of fertilizer concentration in the soil above 30cm. For some element fertilizers with poor mobility, the transfer effect is worse; 3. The absorbing roots are distributed between the soil layers of 0-40cm, the ability of fruit trees to resist drought and waterlogging is weakened, and the three-dimensional space for root growth is reduced; the soil layer of 4.0-40cm is Repeated use year after year, although the mineral nutrients in the soil are replenished every year, there is an imbalance phenomenon, and the soil ecological environment is damaged to varying degrees, such as soil aggregate structure, soil bulk density, microbial colonies, soil carbon/nitrogen ratio, and microbial biomass carbon. , catalase, invertase, urease, alkaline phosphatase, etc. For example, for fruit trees that are more than 20 years old, the absorbing roots under the crown continuously absorb soil mineral nutrients - growth - death - regrowth - death again, and so on and so forth to supply the nutrients needed for the growth of the above-ground parts. The 30-40cm deep soil can obtain some nutrients by gradient descending transfer and maintain the growth of a small amount of roots. The 40-80cm and deeper soils cannot receive various nutrient supplements, and the own soil nutrients can only be absorbed and reduced year by year. The mineral nutrients in the soil are depleted year by year. The so-called "old people get old legs first, trees die before roots die", is because the nutrients in the deep soil of fruit trees are not replenished, resulting in the deep roots being starved to death. That is to say, in general, due to the general pattern of fruit trees growing year by year, the three-dimensional space for root growth is gradually reduced; this leads to the death of underground roots and the weakened absorption capacity, which in turn leads to insufficient nutrients, weaker growth, and weaker growth of aboveground branches. The amount of fruiting decreases and the tree begins to weaken.

The invention patent of the invention patent application 201610280517.X discloses "a method of drilling and fertilizing fruit trees", which solves the problems of the traditional fertilization method that damages the roots, wastes manpower, and the fertilization method is slow. The fertilization method described in this application is light root damage, but this method is used for basal fertilizer application, and the applied basal fertilizer is a basal fertilizer formed by organic fertilizers such as livestock manure into a cylinder, and the diameter of the fertilization hole is 15-30cm and the depth is 30-50cm. The diameter of the forming cylinder is 1-3cm smaller than that of the fertilization hole, and the depth is 5-15cm shorter; the steps of forming the base fertilizer are increased, thereby increasing the cost. In addition, the invention ignores that the organic fertilizer compost is the function of microorganisms to decompose macromolecular organic matter into small molecular organic matter, which is beneficial to the absorption of capillary roots; while it squeezes the organic fertilizer into column-type organic fertilizer, it also decomposes the organic fertilizer in the organic fertilizer. The air is squeezed out, resulting in hypoxia, which delays the decomposition of organic matter by microorganisms, which is not conducive to the exertion of fertilizer efficiency. Utility model patent ZL 201521018878.4 discloses "an integrated casing fertilization device for fruit tree drilling and fertilization", which inserts a plastic pipe with a diameter of 5-20cm and a length of 50-80cm into the soil in the direction of the main root of the tree, and requires a plastic pipe wall. There are small holes, the insertion angle is 60-70° with the ground, the fertilization deep hole interval is 60-100cm, the service period is 20 years, and the fertilizer is liquid fertilizer. With the fertilization device described in this application, the roots can be guided to develop deep into the soil; however, the plastic pipe is inserted into a fixed position under the tree, only liquid fertilizer can be used, the absorbing roots are all around the fertilization casing, and the utilization rate of other soil space is still very high. Low.

The traditional fertilization method has heavy root damage and shallow fertilization depth, and cannot fertilize and repair the soil layer 40-80 cm or even deeper below the canopy width. How to fertilize the deep soil, adjust the soil ecological environment and ensure the normal growth of fruit trees. Restoration, cultivation of microbial colonies, etc., are the problems to be solved by the present invention.

SUMMARY OF THE INVENTION

Aiming at the problem that the living conditions of the deep soil of the old trees in the orchard are deteriorating day by day, which leads to the weakening of the fruit tree and the reduction of the yield, the present invention provides a method for improving the deep soil of the old trees in the orchard. The method of the invention fertilizes the deep soil under the canopy, restores the soil ecological environment and microbial colonies, adjusts the pH value of the soil, expands the deep root growth space and absorbs the number of roots of fruit trees, and provides guarantee for stable and high yield of fruit trees and slowing down tree senescence.

The method for improving the deep soil of old trees in orchards includes the following steps: (1) planning: planning drill holes with scattered distribution points, the drill holes are located inside the vertical projection of the tree crown, and the distance from the trunk of the old tree is not less than 80cm; ( 2) Drilling holes: Use a drill bit with a diameter of 15-20cm, according to the planned position, drill a hole with a depth of 50-80cm. When the drill bit is lifted, all the soil in the hole will be taken out, and the hole will be inserted and drilled quickly. The matching fertilization cylinder can prevent the inner wall of the drilling hole from collapsing and affecting the drilling depth; (3) Fertilization: according to the needs of soil improvement, apply pre-mixed formula fertilizer, pull out the fertilizing cylinder after fertilization, and fill the drilling hole. Using a drill bit with a diameter of 15-20cm is the optimal diameter to ensure the maximum fertilization amount and the minimum damage to the roots of the 40-80cm drilling hole; the drilling hole is light to damage the roots of large trees, and the fertilization depth is deep and adjustable. Using this feature, according to the deep soil According to the sampling analysis, there are steps to fertilize the soil, restore the soil ecological environment, and adjust the soil pH value year by year.

Wherein, the specific distribution of the point-scattered drilling holes in step (1) is as follows: the number of the drilling holes is 1-2 holes per 0.8-1.2 m ² of ground area per year. Wherein, the drilling of 1 hole per year refers to drilling one hole every spring or autumn; the drilling of 2 holes per year refers to drilling a hole in spring and autumn each.

Wherein, the drilling holes described in step ( ² ) are drilled year by year according to batches, and the holes are continuously drilled for 4-5 years. The positions of all the drilled holes do not coincide. Thereby, the comprehensive improvement of the deep soil under the canopy is realized, the yield of fruit trees is guaranteed, and the economic benefit is improved.

Wherein, the fertilization method described in step (3) is specifically the following three types: 1. all the spaces of the drilling holes are filled with fertilization; 2. the space A of the drilling holes far from the surface is fertilized, and the space B close to the surface is filled with soil, the step 2. The minimum distance from the space A to the ground surface is 40cm, and the depth of the space A is 10-40cm; so as to achieve the purpose of applying fertilizer to a certain depth. ③ Apply formula fertilizer to the space A where the hole is drilled away from the surface, and fill the space B close to the surface with B fertilizers; there is a certain interval between the A space and the B space. Described step 3. space A is 40cm from the surface minimum distance, the depth of described space A is 10-40cm; The depth of described space B is 30-40cm, and the interval between described formula fertilizer and B kind of fertilizer is 0- 10cm, the space is filled with soil, grass or straw powder.

Wherein, the formula fertilizer includes the following components in parts by weight: 5-30 parts of inorganic fertilizer, 30-60 parts of organic fertilizer, 1-10 parts of beneficial bacteria, and 20-40 parts of soil. The inorganic fertilizer is one or two or three kinds of nitrogen, phosphorus and potassium, one or more of calcium fertilizer, magnesium fertilizer, boron fertilizer, zinc fertilizer and iron fertilizer. The organic fertilizer is one or more of soybean meal powder, plant straw powder mixed with beneficial bacteria, seaweed residue, furfural residue, and livestock manure fermented by beneficial bacteria. The dosage of the beneficial bacteria species is not more than 10%; the beneficial bacteria species are lactic acid bacteria, yeast bacteria, photosynthetic bacteria, Gram-positive actinomycetes, fermentative filamentous bacteria and Bacillus subtilis. several or all. The proportion of the soil is not less than 20%, and its function is to eliminate the excessive osmotic pressure of the fertilizer, which is beneficial to the absorption of the fertilizer by the roots. The formula fertilizer can supplement nitrogen, phosphorus and potassium and medium and trace elements to soil, increase organic matter, adjust soil pH value, improve soil aggregate structure, and increase soil microbial colony.

The formula fertilizer also includes compound microbial organic fertilizer, and the proportion of the compound microbial organic fertilizer is not more than 50% in parts by weight. The formula fertilizer includes the following components in parts by weight: 4.5-30 parts of inorganic fertilizer, 15-60 parts of organic fertilizer, 0.5-8 parts of beneficial bacteria, 10-40 parts of compound microorganism organic fertilizer, 20- 40 parts soil. The compound microbial organic fertilizer is a commercially available compound microbial organic fertilizer (manufacturer: Rizhao Yikang Organic Agriculture Technology Development Co., Ltd.; trade name: Haishengbao brand compound microbial organic fertilizer). It contains high-quality organic matter, compound beneficial bacteria, fulvic acid, amino acids, plant endogenous enzymes, and natural medium and trace elements required for the growth of calcium, silicon, iron and magnesium plants. Improve fertilizer utilization, increase root stress resistance, adjust soil pH, and improve soil aggregate structure to increase water retention and permeability.

The purpose of the above formula fertilizer is to increase soil organic matter content, increase the number of microbial colonies, improve soil fertility, loosen soil to increase air permeability, adjust soil pH, increase soil aggregate structure, increase deep root growth space and the total amount of roots absorbed by the tree body. Depending on soil conditions, certain fertilizers can be removed or added. Whether basal fertilizer or top dressing, the above formula and method can be used. The formula fertilizer is suitable for the space A far from the surface in the fertilization method ① or the method ②/③; the space B close to the surface in the method ②/③ is filled with soil or B type of fertilizer is used as required, and the B type of fertilizer is: NPK compound fertilizer, compound microbial organic fertilizer or special fertilizer for fruit trees.

Beneficial effects of the present invention:

(1) The method for improving the deep soil of old trees in orchards of the present invention, fertilizes the deep soil under the canopy, restores the soil ecological environment and microbial colonies, adjusts the soil pH value, expands the deep root growth space of fruit trees and absorbs the number of roots, and makes the tree body The ability to resist drought and waterlogging has been increased, providing a guarantee for the stable and high yield of fruit trees to slow down tree senescence.

(2) The present invention adopts a drill bit with a diameter of 15-20 cm, which ensures that the maximum fertilization amount and the minimum degree of root injury of the drilling hole with a depth of 40-80 cm are used; According to this characteristic, according to the sampling analysis of the deep soil, there are steps to fertilize the soil year by year, restore the soil ecological environment, adjust the pH value of the soil, loosen the deep soil to increase the soil permeability;

(3) The present invention adopts the method of drilling in batches year by year, thereby realizing the comprehensive improvement of the deep soil under the canopy in 4-5 years, ensuring the yield of fruit trees, and improving the economic benefit.

Detailed ways

The present invention will be further described below in conjunction with the embodiments.

A 50-year-old orchard of Laiyang pear was used to draw out 7 experimental fields, 6 of which were fertilized with the formulas of Examples 1-6 respectively, and the remaining experimental field was reserved as a blank control group. The row spacing is 5×6, and a hole is drilled every 0.8-1.2 square meters, with a depth of 50--80cm.

Example 1:

The deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: the drilling holes with scattered distribution of planning points, the drilling holes are located inside the vertical projection of the tree crown, and the distance from the trunk of the old tree is not less ^than 80cm; 1 hole. .

(2) Drilling: Use a drill bit with a diameter of 20cm. According to the planned position, drill a hole with a depth of 50cm. When the drill bit is lifted, all the soil in the hole will be taken out, and the fertilization matching the hole will be quickly inserted into the hole. To prevent the inner wall of the drilling hole from collapsing and affecting the drilling depth; the drilling holes are drilled year by year in batches, and the holes are continuously drilled for 4-5 years. ^The annual drilling density reaches 1.0m2 per ground area. , the positions of all the drilled holes are not coincident.

(3) Fertilization: apply the pre-stirred formula fertilizer, pull out the fertilization cylinder after fertilization, and fill up the drilling hole; the fertilization method is: ② fertilize the space A where the drilling hole is far from the surface, and the space close to the surface B is filled with soil, the depth of the space B is 40 cm, and the depth of the space A is 10 cm.

Wherein, the formula fertilizer includes the following components in parts by weight: 5 parts of inorganic fertilizer, 45 parts of organic fertilizer, 10 parts of beneficial bacteria, and 40 parts of soil. Preparation method: Weigh 2kg of urea, 2kg of calcium fertilizer, 1k of magnesium fertilizer, 20kg of soybean meal, 25kg of straw powder, 10kg of beneficial bacteria, and 40kg of soil. Mix other fertilizers evenly.

Example 2:

Different from Example 1, the deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: The number of holes to be drilled is one hole per ^1.2m2 of ground area every spring.

(2) Drilling holes: using a drill bit with a diameter of 15 cm, according to the planned position, drilling holes with a depth of 60 cm; drilling holes are drilled year by year according to batches,

(3) Fertilization: The specific fertilization method is as follows: ① All the spaces of the drilling holes are filled with fertilizer. The formula fertilizer includes the following components in parts by weight: 4.5 parts of inorganic fertilizer, 15 parts of organic fertilizer, 0.5 part of beneficial bacteria, 40 parts of compound microorganism organic fertilizer, and 40 parts of soil. Preparation method: weigh 2.5kg of diammonium phosphate, 1kg of zinc fertilizer, 1kg of boron fertilizer, 5kg of seaweed slag, 10kg of livestock manure, 0.5 kg of beneficial bacteria, 40kg of compound microbial organic fertilizer, and 40kg of soil, and dilute the bacteria to 30 times the mother liquor, After mixing with organic fertilizer and soil, then mix with other fertilizers evenly.

Example 3:

Different from Example 1, the deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: The number of holes to be drilled is one hole per ^0.8m2 of ground area every autumn.

(2) Drilling: A drill with a diameter of 18cm is used, and according to the planned position, a hole with a depth of 70cm is drilled; the holes are drilled year by year according to batches.

(3) Fertilization: The fertilization method is specifically: 2. fertilize the space A where the hole is drilled away from the surface, fill the space B close to the surface with soil, the depth of the space B is 40cm, and the depth of the space A is 30cm.

The formula fertilizer includes the following components in parts by weight: 30 parts of inorganic fertilizer, 30 parts of organic fertilizer, 5 parts of beneficial bacteria, and 35 parts of soil. Preparation method: Weigh 20kg of nitrogen, phosphorus and potassium three-element compound fertilizer, 10kg of medium and trace element fertilizer, 10kg of soybean meal powder, 10kg of furfural residue, 10kg of livestock manure, 5kg of beneficial bacteria, and 35kg of soil. After the organic fertilizer and soil are evenly mixed, they are then mixed with other fertilizers evenly.

Example 4:

Different from Example 1, the deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: The number of holes to be drilled is one hole per ^0.9m2 of ground area in spring and autumn each year.

(2) Drilling holes: using a drill bit with a diameter of 20 cm, according to the planned position, drilling holes with a depth of 80 cm; drilling holes are drilled year by year according to batches.

(3) Fertilization: The fertilization method is specifically as follows: 3. Apply formula fertilizer to the space A where the hole is drilled away from the surface, and fill the space B close to the surface with B kinds of fertilizers; there is a certain interval between the A space and the B space. The depth of the space A is 40 cm; the depth of the space B is 30 cm, and the interval between the formula fertilizer and the type B fertilizer is 10 cm, and the interval is filled with soil, broken grass or straw powder.

The formula fertilizer includes the following components in parts by weight: 7 parts of inorganic fertilizer, 60 parts of organic fertilizer, 3 parts of beneficial bacteria, 10 parts of compound microorganism organic fertilizer, and 20 parts of soil. Preparation method: weigh 4kg of urea, 1kg of magnesium fertilizer, 1kg of zinc fertilizer, 1kg of boron fertilizer, 15kg of soybean meal powder, 20kg of seaweed residue, 15kg of plant straw, 10kg of livestock manure, 3kg of beneficial bacteria, 10kg of compound microbial organic fertilizer, and 20kg of soil. , Dilute the strain by 10 times the mother liquor, stir evenly with organic fertilizer and soil, and then stir evenly with other fertilizers. The B kind of fertilizer is a commercially available compound microbial organic fertilizer.

Example 5:

Different from Example 1, the deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: The number of holes to be drilled is one hole per ^1.1m2 of ground area every spring.

(2) Drilling holes: using a drill bit with a diameter of 20 cm, according to the planned position, drilling holes with a depth of 80 cm; drilling holes are drilled year by year according to batches.

(3) Fertilization: The fertilization method is specifically as follows: 3. Apply formula fertilizer to the space A where the hole is drilled away from the surface, and fill the space B close to the surface with B kinds of fertilizers; there is a certain interval between the A space and the B space. The depth of the space A is 40 cm; the depth of the space B is 40 cm.

The formula fertilizer includes the following components in parts by weight: 19 parts of inorganic fertilizer, 60 parts of organic fertilizer, 1 part of beneficial bacteria, and 20 parts of soil. Preparation method: Weigh 12 kg of nitrogen, phosphorus and potassium compound fertilizer, 7 kg of medium and trace element fertilizer, 10 kg of seaweed residue, 10 kg of furfural residue, 10 kg of plant straw, 30 kg of livestock manure, 1 kg of beneficial bacteria, and 20 kg of soil, and dilute the bacteria by 30 times. , After mixing with organic fertilizer and soil, and then mixing with other fertilizers evenly. The B fertilizers are commercially available nitrogen-phosphorus-potassium compound fertilizers.

Example 6:

Different from Example 1, the deep soil improvement method for old trees in orchards includes the following steps:

(1) Planning: The number of holes to be drilled is ¹ hole per 1.0m2 of ground area every autumn.

(2) Drilling holes: using a drill bit with a diameter of 20 cm, according to the planned position, drilling holes with a depth of 80 cm; drilling holes are drilled year by year according to batches.

(3) Fertilization: The fertilization method is specifically as follows: 3. Apply formula fertilizer to the space A where the hole is drilled away from the surface, and fill the space B close to the surface with B kinds of fertilizers; there is a certain interval between the A space and the B space. The depth of the space A is 40 cm; the depth of the space B is 35 cm, and the interval between the formula fertilizer and the type B fertilizer is 5 cm, and the interval is filled with soil, broken grass or straw powder.

The formula fertilizer includes the following components in parts by weight: 30 parts of inorganic fertilizer, 17 parts of organic fertilizer, 8 parts of beneficial bacteria, 15 parts of compound microorganism organic fertilizer, and 30 parts of soil. Preparation method: weigh 20kg of diammonium phosphate, 4kg of calcium fertilizer, 2kg of boron fertilizer, 1kg of zinc fertilizer, 1kg of magnesium fertilizer, 2kg of iron fertilizer, 10kg of plant straw, 7kg of livestock manure, 8kg of beneficial bacteria, 15kg of compound microorganism organic fertilizer, 30kg of soil, dilute the strain by 5 times the mother liquor, stir evenly with organic fertilizer and soil, and then stir evenly with other fertilizers. The B kind of fertilizer is a commercially available special fertilizer for fruit trees.

new multiplier

Table 1. Comparison of various growth indicators and soil indicators of old trees after soil improvement

It can be seen from Table 1 that compared with the control group, the degree of increase in soluble solids increased by 1.8-2.7 degrees, and the taste was better. Among the multiples of new shoots, the multiples of long shoots are increased by 1.5-2.3 times, the multiples of middle shoots are increased by 1.7-2.0 times, and the multiples of short shoots are reduced by 1.5-2.0 times; therefore, the tree body has sufficient nutrition, the branches are fully developed and robust, and the photosynthetic efficiency is The higher the value, the more flower buds are formed, and the flower body is full, so the next year blooms early, the flower body is large, and the fruit is also large. The organic matter in the soil is increased by 15.3-18.5 times, the urease is increased by 5.1-6.4 times, the catalase is increased by 1.1-16 times, and the amount of humic acid and carbon is increased by 11.5-15.1 times, indicating that the method of the present invention is adopted. After improving the soil of old trees in the orchard, the fertility of the soil has been greatly restored, which not only provides sufficient organic matter and nitrogen for the fruit trees, but also increases the total amount of humic acid in the humus, improves the cation exchange capacity, and is beneficial to the soil. The formation of aggregates in the soil, which in turn allows the soil to form a good structure.

Claims (9)

1. The method for improving the deep soil of old trees in orchards is characterized in that: comprising the following steps: (1) Planning: planning drill holes with scattered distribution points, and the drill holes are located inside the vertical projection of the canopy, and are farther away from the trunk of the old tree. The distance is not less than 80cm; the specific distribution of the scattered holes in step (1) is: the number of the holes is 1-2 holes per 0.8-1.2m2 of the ground area per year; ( ² ) holes are drilled : Use a drill bit with a diameter of 15-20cm, according to the planned position, drill a hole with a depth of 50-80cm. When the drill bit is lifted, all the soil in the hole will be taken out, and the fertilization tube that matches the hole will be quickly inserted into the hole. ; (3) Fertilization: According to the needs of soil improvement, apply pre-mixed formula fertilizer, pull out the fertilization cylinder after fertilization, and fill the hole. 2. The deep soil improvement method for old trees in orchards according to claim 1, characterized in that: the drilling holes described in step (2) are drilled year by year in batches until the soil improvement is completed, and the density of drilling holes reaches the ground area every year. 1-2 holes are drilled every 0.8-1.2m ² per year, and the positions of all the holes are not coincident. 3. The deep soil improvement method for old trees in orchards according to claim 1, characterized in that: the fertilization method described in step (3) is specifically the following three types: 1. all the spaces for drilling holes are filled with fertilization; 2. for drilling holes The space A far from the surface is fertilized, and the space B close to the surface is filled with soil; ③ the space A where the hole is drilled away from the surface is applied with formula fertilizer, and the space B close to the surface is filled with B fertilizer; there is a certain interval between the space A and the space B . 4. deep soil improvement method for old trees in orchard according to claim 3, is characterized in that: described step 2. space A is 40cm from the surface minimum distance, and the depth of described space A is 10-40cm; Described step 3. space The minimum distance between A and the surface is 40cm, the depth of the space A is 10-40cm; the depth of the space B is 30-40cm, and the interval between the formula fertilizer and the fertilizer B is 0-10cm, and the interval Fill with soil, chopped grass or straw powder. 5. The method for improving the deep soil of old trees in orchards according to claim 3 or 4, wherein the formula fertilizer comprises the following components in parts by weight: 5-30 parts of inorganic fertilizer, 30-60 parts by weight parts of organic fertilizer, 1-10 parts of beneficial bacteria, and 20-40 parts of soil; the dosage of the beneficial bacteria is not more than 10%. 6. deep soil improvement method for old trees in orchard according to claim 5, is characterized in that: described inorganic fertilizer is one kind/two kinds/three kinds of nitrogen, phosphorus and potassium, calcium fertilizer, magnesium fertilizer, boron fertilizer, zinc fertilizer, One or more of iron fertilizers; the organic fertilizer is one or more of soybean meal powder, plant straw powder mixed with beneficial bacteria, seaweed residue, furfural residue, and livestock manure fermented by beneficial bacteria; The beneficial bacteria species are several or all of lactic acid bacteria, yeast bacteria, photosynthetic bacteria, Gram-positive actinomycetes, fermentative filamentous bacteria and Bacillus subtilis. 7. deep soil improvement method for old trees in orchard according to claim 6, is characterized in that: in described formula fertilizer, also comprise compound microbial organic fertilizer, by weight, the ratio of described compound microbial organic fertilizer is not more than 50%. %. 8. The deep soil improvement method for old trees in orchards according to claim 7, wherein the formula fertilizer comprises the following components in parts by weight: 4.5-30 parts of inorganic fertilizers, 15-60 parts of organic fertilizers Fertilizer, 0.5-8 parts of beneficial bacteria, 10-40 parts of compound microbial organic fertilizer, 20-40 parts of soil. 9. deep soil improvement method of old tree in orchard according to claim 6 or 8, is characterized in that: described formula fertilizer is applicable to the space A far from the surface in fertilization method 1. or method 2./3; in method 2./3. The space B close to the surface is filled with soil or B type of fertilizer is used as needed, and the B type of fertilizer is nitrogen-phosphorus-potassium compound fertilizer, compound microbial organic fertilizer or special fertilizer for fruit trees.