CN-122010642-A - Special bag-type fertilizer and method for improving oxygen content of soil by using same

CN122010642ACN 122010642 ACN122010642 ACN 122010642ACN-122010642-A

Abstract

The invention discloses a special bag fertilizer and a method for improving the oxygen content of soil by using the special bag fertilizer, belonging to the technical field of agricultural planting soil improvement and fertilization. The special bag control fertilizer comprises a bag body and functional materials, wherein the bag body is made of polypropylene porous non-woven fabrics, the functional materials comprise a control release fertilizer, perlite, decomposed organic fertilizer and bentonite, the control release fertilizer is coated by a degradable polymer composite film, and the composite film is prepared by pretreatment, pre-crosslinking, melt mixing, modification blending, compounding and film forming liquid preparation, casting, drying and curing of raw materials such as polylactic acid, tapioca starch and the like. When the ventilation device is applied, the ventilation channel is constructed by the cooperation of the bag body and the functional materials through soil pretreatment, special bag layout and later management. The invention realizes the synergistic effect of oxygen supply and fertilizer control, can stabilize the oxygen content of the soil root system layer, improve the activity of the crop root system and the utilization rate of nutrients, reduce the leaching loss of the nutrients, has simple operation and wide adaptability, can be repeatedly used, avoids the pollution and the degradation of the soil, and has production benefit and ecological benefit.

Inventors

HUANG LINGZHI
XU SHIPING
CAO JIZHAO
WANG HUILI
DENG XIAOJUN
QIN QIYUN
PAN BO
SUN ZHIYU
HE JIANYONG
DENG YANQIN

Assignees

广西壮族自治区林业科学研究院

Dates

Publication Date: 20260512
Application Date: 20260214

Claims (10)

1. A special bag fertilizer is characterized by comprising a porous air permeable bag body and functional materials filled in the bag body; The porous air permeable bag body is made of porous non-woven fabrics, the porosity is 30% -40%, the thickness is 0.15-0.2mm, and a plurality of air holes are uniformly formed in the bottom and the side surfaces of the bag body; The functional material consists of the following raw materials, by weight, 70-85 parts of a controlled release fertilizer, 3-5 parts of a light breathable medium, 5-8 parts of an organic fertilizer and 2-3 parts of a soil conditioner, wherein the filling amount of the functional material is 70% -80% of the volume of the bag body; the controlled release fertilizer is fertilizer particles coated by adopting a degradable polymer composite film; The degradable polymer composite film is prepared from 40-50 parts of polylactic acid, 15-20 parts of starch, 5-8 parts of cellulose derivative, 3-5 parts of plasticizer, 2-4 parts of cross-linking agent, 1-3 parts of nano filler, 2.5-4 parts of antibacterial agent, 3-6 parts of dispersing agent, 1-2 parts of anti-aging agent, 2-3 parts of binder, 3-5 parts of film forming additive, 2-4 parts of auxiliary plasticizer, 3.5-5 parts of reinforcing fiber and 1.5-2.5 parts of degradation rate regulator.
2. The special bag fertilizer according to claim 1, wherein the porous non-woven fabric is polypropylene porous non-woven fabric, the diameter of the air holes is 0.5-1cm, the distance between the holes is 5-8cm, and the size of the bag body is 30-40cm in length and 20-25cm in width.
3. The special bag fertilizer according to claim 1, wherein the light breathable medium is perlite with a particle size of 1-2mm, the organic fertilizer is decomposed organic fertilizer, and the soil conditioner is bentonite.
4. The special bag control fertilizer according to claim 1, wherein the starch is tapioca starch, the cellulose derivative is hydroxypropyl methyl cellulose, the plasticizer is glycerin, the cross-linking agent is tannic acid, the antibacterial agent is chitosan, the anti-aging agent is phytosterol, the binder is sodium alginate, the film forming auxiliary agent is polyvinyl alcohol, the auxiliary plasticizer is sorbitol, the reinforcing fiber is microcrystalline cellulose, the degradation rate regulator is calcium lactate, and the nanofiller comprises nano silicon dioxide and a light stabilizer.
5. The special bag fertilizer according to claim 4, wherein the light stabilizer is titanium dioxide, the weight ratio of the tannic acid to the calcium lactate is1 (0.5-1), and the weight ratio of the titanium dioxide to the nano silicon dioxide is1 (1-2).
6. A method of preparing a degradable polymer composite film for a dedicated bag fertilizer according to any one of claims 1-5, comprising the steps of: (1) Raw material pretreatment, namely weighing the raw materials according to the proportion, drying polylactic acid, drying starch, sieving, dissolving chitosan with acid solution to prepare chitosan solution, sieving microcrystalline cellulose for standby; (2) Preparing a pre-crosslinking liquid, namely mixing tannic acid and calcium lactate with a part accounting for 30-50% of the total weight of the plasticizer and the auxiliary plasticizer, and stirring and reacting under a heating condition to obtain the pre-crosslinking liquid; (3) Melting and mixing the base materials, namely mixing the pretreated polylactic acid, starch, hydroxypropyl methyl cellulose, polyvinyl alcohol and microcrystalline cellulose, and melting and blending under heating and stirring to obtain a base mixture; (4) Adding the rest plasticizer, auxiliary plasticizer, dispersant, nano filler and light stabilizer into the basic mixture, and carrying out blending modification under stirring to obtain a modified blend; (5) Preparing a composite and film-forming solution, namely adding the chitosan solution, the plant sterol, the sodium alginate and the pre-crosslinking solution into the modified blend, stirring and mixing, then adding water, regulating the solid-liquid mass ratio of the system to be 1 (3-5), stirring at constant temperature, and filtering to obtain uniform film solution; (6) Casting, drying and curing, namely casting the film on a substrate, controlling the thickness of a wet film, primarily drying, and balancing and curing to obtain the degradable polymer composite film with the target thickness.
7. The method of degradable polymer composite membrane according to claim 6, wherein in step (6), the wet membrane thickness is 0.1-0.16mm, the preliminary drying temperature is 40-50 ℃, the equilibrium curing condition is temperature 25 ℃, relative humidity is 50% -60%, time is 24-48 hours, and the obtained composite membrane thickness is 0.05-0.08mm.
8. A method for increasing the oxygen content of soil by using the special bag fertilizer according to any one of claims 1 to 5, which is characterized by comprising the following steps: (1) Soil pretreatment, namely crushing and screening the soil of a target land block, adjusting the volume weight, the water content and the pH value of the soil, and ploughing; (2) The special bags are laid, namely, the laying interval is determined according to the planting type, planting ditches or planting holes are excavated in the soil, the special bags are laid according to the set depth, the soil is covered and compacted; (3) And (3) planting and managing crops, namely planting crops in the area where the special bags are distributed, irrigating, and periodically checking the smoothness of the ventilation holes of the bag body.
9. The method for improving the oxygen content of soil by using the special bag fertilizer according to claim 8, wherein in the step (1), the soil volume weight is adjusted to 1.1-1.3g/cm 3 , the mass water content is adjusted to 20% -25%, the pH value is adjusted to 6.0-7.5, in the step (2), the row spacing of open field planting is 30-40cm, the plant spacing is 25-30cm, the row spacing of facility planting is 25-35cm, the plant spacing is 20-25cm, the laying depth is 15-20cm, and in the step (3), the irrigation frequency is once every 3-5 days, so that the soil mass water content is maintained to 30% -35%, and the frequency of checking ventilation holes is once every 15-20 days.
10. The method for improving the oxygen content of soil by using the special bag fertilizer according to claim 8, which is characterized by further comprising a bag body treatment step after crop harvesting, wherein the porous air permeable bag body is recovered, the consumed functional materials remained in the bag are removed, and new functional materials with the same composition as the functional materials are supplemented into the bag body.

Description

Special bag-type fertilizer and method for improving oxygen content of soil by using same Technical Field The invention relates to the technical field of agricultural planting soil improvement and fertilization, in particular to a special bag fertilizer and a method for improving the oxygen content of soil by using the special bag fertilizer. Background In agricultural production, the oxygen content and nutrient supply of soil are core factors influencing the growth, yield and quality of crops, and the cooperative optimization of the oxygen content and the nutrient supply is the key of quality improvement and sustainable development of modern agriculture. The oxygen sufficient in the root system layer of the soil is the basis of respiration, nutrient absorption and metabolic activity of the root system of the crop, the oxygen deficiency can lead to the reduction of the activity of the root system, rotten roots and disease breeding, scientific nutrient supply needs to be matched with the growth period requirement of the crop, and meanwhile, the soil structure is protected, and the soil degradation caused by improper fertilization is avoided. However, current soil oxygen supply and nutrient regulation technologies are long-term split, and the current soil oxygen supply and nutrient regulation technologies have bottlenecks which are difficult to break through, so that the comprehensive optimization requirements of the soil environment cannot be met. In the aspect of the soil oxygen supply technology, the traditional means mainly comprises deep ploughing and soil loosening, adding a coarse medium and paving an air duct. Deep ploughing loosens soil and breaks a plate layer through machinery, but irrigation, rainfall and root system growth can quickly lead to soil re-compaction, the ventilation effect is short, repeated operation is needed, time and labor are consumed, the soil structure can be damaged, a continuous ventilation channel is difficult to construct due to the fact that coarse media are added to improve the ventilation property for a short period, the ventilation channel is easy to block and extremely poor in stability, the ventilation pipeline is complex to install, high in cost and high in maintenance difficulty, and the ventilation channel is only suitable for large-scale facility agriculture and is difficult to popularize. More importantly, the single oxygen supply technology does not consider the influence of fertilization on soil ventilation, and the soil structure is easy to be unbalanced and the hypoxia is aggravated after long-term use. In the field of nutrient regulation and control, the traditional fertilizer is quick to release, is not matched with the fertilizer requirement rule of crops, has serious nutrient leaching loss, is low in utilization rate, can also cause soil acidification and salinization, damages a granular structure and indirectly reduces the air permeability of soil, the existing controlled release fertilizer can regulate and control the nutrient release through a coating, but does not consider the air permeability requirement of the soil, the coating material is poor in degradability and residual to pollute the soil, or is too fast to degrade and can not realize long-term controlled release, and the gas permeation is not considered by the coating structure, so that the nutrient controlled release and the air permeability requirement of the soil are difficult to be cooperatively met. Meanwhile, the controlled release fertilizer and the oxygen supply measure are cut, so that even if the nutrient release is reasonable, the nutrient absorption efficiency of crops can be greatly reduced due to the lack of oxygen in the soil. More prominently, the cutting of the oxygen supply and fertilizer control technology forms a vicious circle, namely, the nutrition imbalance can not be solved by single oxygen supply, the soil hardening and the hypoxia are aggravated, and the ventilation is not carried out by single fertilizer control, so that the soil structure is degraded, and the ventilation performance is further reduced. In addition, the demand difference of different soil types and planting scenes on oxygen supply and nutrients is obvious, the adaptability of the prior art is poor, ventilation and reinforcement of the sticky soil are insufficient, the sandy soil is difficult to consider both water retention and fertilizer retention and ventilation, and the fertilizer requirement rules and root system distribution differences of different crops cannot be met pertinently through the prior art, so that the universality is extremely poor. In the field of coating materials, the traditional polylactic acid coating has large brittleness, difficult degradation rate regulation and control, poor film forming property of a starch-based coating, insufficient strength, single raw materials of the existing composite coating material, and lack of scientific synergistic mechanism, and can not simult