Scientific fertilization plays an important role in ensuring high yield, stable yield, high quality, safety, low cost, and prevention of environmental pollution. The fertilization method should be based on soil fertilization, and the combination of soil fertilization and top dressing fertilizer should be adhered to. Here is a review of the problems that should be paid attention to when fertilizing fruit trees, so as to improve the effect of fertilization.
First, soil fertilization
1, find the location of fertilization: fine roots (absorbing roots) of fruit trees are more concentrated in the soil layer on both sides of the crown below the drip line, in order to promote root absorption, improve fertilizer efficiency, fertilization location should be in a canopy below the external drip line In the dense rooted soil, open strips (30–40 cm in width, 20–60 cm in depth) or radial sulcus are used for production (4 to 6 radii around the trunk, and 30 to 30 in width). 40cm, fertilization ditch shallow depth 20-60cm) way fertilization. Fertilizer must not be applied to the trunk next to the fertilizer or it will easily hurt the big roots, and the applied fertilizer is not easy to be absorbed and used, affecting fertilizer efficiency. The depth of fertilization should be determined according to the dense roots, the fertilization period, and the type of fertilizer. Generally, deep root distribution should be applied deep, and vice versa. Shallow application of base fertilizer, top dressing can be applied lightly; Fertilizers must be applied deeply, and quick-acting fertilizers can generally be applied. In fertilizers. Easy-flowing nitrogen fertilizers can be applied lightly, and moderately fluid potassium fertilizers should be slightly deeper. Phosphorus fertilizers that are not easy to flow and are easily fixed by the soil should be applied deep to the site where the fine roots are distributed most, and it is best to mix with organic fertilizers to increase the effectiveness of phosphorus. Each fertilization should pay attention to rotating fertilization sites to expand the fertilization surface, promote root absorption and increase fertilizer efficiency.
2. Adhere to the combination of organic and inorganic fertilizers. Nitrogen, phosphorus, and potassium are used in combination: organic fertilizers have comprehensive nutritive elements, fertilizer effect is slow and lasting, and chemical fertilizers are simple, nutrient content is high, and fertilizer efficiency is fast. Organic fertilizers and quick-acting fertilizers can be used in conjunction with Economic, complementary, and at the same time, the humus produced by the decomposition of organic matter has the ability to adsorb ammonium, potassium, magnesium, calcium, iron and other ions, thereby reducing the loss of fertilizer and improving fertilizer efficiency. During the annual growth cycle of fruit trees, organic nitrogen and inorganic nitrogen can be applied in a ratio of 1:1. Applying this method of fertilization can not only significantly increase soil organic matter content, but also achieve good effects of soil fertility improvement and increase soil efficiency. Nutrient content promotes normal growth and development of plants. In order to exert the synergistic effect of nitrogen, phosphorus, and potassium, the ratio of nitrogen (N) and phosphorus (P2O5 ≥ potassium) (K2O) in adult trees is generally kept at a ratio of 2:1:2. Nitrogen is used in young trees (N). The ratio of phosphorus (P2O5) and potassium (K2O) can be 1:0.3-0.5:0.4-0.8, and the dosage of phosphorus and potassium can be gradually increased as the age of trees increases.
3, pay attention to the mixed use of fertilizer: the mixing of different fertilizers, must not lose nutrients, do not change the chemical properties, help to improve the efficiency of fertilizer and ergonomic principles, or can not be mixed application. Fertilizers that can be mixed in production include ammonium sulfate, ammonium chloride and other physiological acidic fertilizers, phosphate rock powder, calcium magnesium phosphate fertilizer, ammonium sulfate and superphosphate, urea and superphosphate, calcium magnesium phosphate fertilizer, and magnesium sulfate (manganese). , borax (acid), manure, potassium sulfate, calcium perchlorate and urea, potassium chloride, potassium sulfate, manure, lime nitrogen and potassium sulfate, potassium chloride, fresh barium fertilizer, compost and ammonium nitrogen fertilizer, potash fertilizer, phosphorus Mineral powder, calcium magnesium phosphate fertilizer, calcium superphosphate, steel slag phosphate, grass ash, lime, manure, etc. can all be mixed and applied. Plant ash, lime nitrogen, lime, calcium magnesium phosphate, cellar ash potash and other alkaline fertilizers and decomposed organic fertilizer, superphosphate, ammonium nitrogen fertilizer, ferrous sulfate and other acidic fertilizers, steel slag phosphate fertilizer and cellar ash potash, bone meal, phosphate rock Powder and alkaline fertilizers, superphosphate and ammonium bicarbonate cannot be mixed, otherwise it is easy to cause loss of nutrients and reduce fertilizer efficiency. The combination of decomposed organic fertilizer and 3%-5% superphosphate can reduce the loss of ammonium nitrogen from organic fertilizer to gaseous nitrogen, and can increase the availability of phosphorus. Fertilizer should be applied in a timely manner after mixing, with the mixing with the application, try not to mix too early. Fertilizers that cannot be mixed must be applied several days apart.
4, fertilization depends on the day, see the land, see fertilizer, see the tree: the soil fertilization needs specific control according to the specific conditions, do not apply before heavy rain, grab after the rain; wet season, dry season, dry season, thick Shi; winter basal fertilizer to be applied early, the South not later than the end of November. Alkaline fertilizers are used in acid soils in red and yellow soils, and acidic fertilizers are used in alkaline soils. The ability to retain water and fertility is poor in sandy soils. Thin and thin soils should be applied frequently, and viscous heavy soils should be appropriately replanted; mountainous lands should be deeply applied and furrowed. In order to neutralize the excessively acidic nature of the soil, lime must be added. The garden with shallow soil and high groundwater level should be properly applied. Fertilizers are generally added with water to avoid over-concentration, roots, cakes, and garbage should be composted and then cooked. Green manure should be turned over in the flowering stage or the crusting stage, usually divided into 2-3 layers, each layer needs to be applied with appropriate amount of lime. If the superphosphate is applied at the same time, it should be applied separately and cannot be mixed with lime. Fertilizers and farmyard manures should be dry-applied. Fertilizers should be mixed with the soil in the ditch and be timely covered with soil after the application. Conditional orchards should be promptly filled with water to promote the dissolution and absorption of nutrients. The amount of irrigation water after fertilization should not be large, and the water-soluble fertilizer infiltration should be concentrated in the root distribution layer. Fertilization should be balanced according to the strength of tree vigor, tree species characteristics, soil fat, tree size, and yield abundance afforestation. Generally, afforestation should be applied more frequently and fertilizer should be used less frequently; Orange and other fertility tree species should be applied in multiple ways, and orange-tolerant species such as oranges can be used less properly; high-yielding trees, weak trees and multiple trees, low-yield trees, and strong-strong trees can be used less frequently; and big-year trees can be replanted with nitrogenous fertilizers, combined with phosphorus and potash fertilizers. The young trees are increased with phosphorus and potassium fertilizers. Conditional orchards should promote soil testing and formula fertilization to achieve balanced supply of various nutrients and improve efficiency of fertilization.
5. Does not have adverse effects on the environment and fruit trees: organic manure, manure, farm waste, municipal solid waste, sludge and other organic fertilizers must be harmlessly treated. These fertilizers hide a large number of germs and parasite eggs. Applying directly to the soil without treatment not only contaminates the soil environment, but also causes root damage due to the high temperatures produced during fermentation. The use of nitrate-based fertilizers, excessive heavy metals, antibiotics and other harmful substances such as garbage, sludge and excrement should be prohibited in production. For fruit trees that are sensitive to chlorine, such as oranges, pears, apples, and peaches, fertilization should pay attention to the control of the application of chlorinated fertilizers and chlorine-containing (mixed) fertilizers. It is best to use chlorinated fertilizers and chlorine-containing compound fertilizers. Apply organic fertilizer and phosphate fertilizer, and try to make basal fertilizer as much as possible to prevent damage to fruit trees due to excessive chloride ions. It is best to stop the soil top dressing within 30 days before fruit picking to avoid adverse effects on the fruit.
Second, outside the top dressing
1, master the spray fertilizer concentration: fruit trees outside the top dressing, should grasp the appropriate concentration, over-concentration is easy to produce fertilizer damage, too little effect is not. In the absence of fertilizer damage, high concentrations should be used as much as possible to satisfy the fruit tree's demand for nutrients. The foliar spraying fertilizer concentration commonly used in the growing season is: urea 0.2%-0.4%, potassium sulfate (potassium chloride) 0.3%-0.5%, ammonium phosphate 0.5%-1%, potassium dihydrogen phosphate 0.2%-0.5%, over Calcium phosphate 0.5%-1%, ash 1%-3%, decomposed human urine 10%-30%, biogas slurry 50%-100%, nitrogen-phosphorus potassium ternary compound fertilizer 0.3%-0.5%, manganese sulfate 0.05%- 0.1%, borax (acid) 0.1%-0.2%, zinc sulfate 0.1%-0.3%, ferrous sulfate 0.1%-0.2%, magnesium sulfate 0.1%-0.3%, rare earth nitrate 0.05%-0.1%, copper sulfate 0.01% - 0.02%. When the temperature is low, the humidity is high, and the leaves are old, the use concentration is too high, which can easily cause fertilizer damage. To promote new leaf fertilizers, small tests should be conducted first to avoid fertilizer damage. Outside the root dressing, in addition to the growing season, the dormancy period can also be carried out. The concentration of urea sprayed by the evergreen fruit tree can be increased to 0.5% in winter. Nitrogen spraying outside the root during dormancy can increase nutrient storage of the tree, help to overcome the annual phenomenon of fruit tree size, and increase flower quality and fruit setting rate, so that the fruit tree can maintain stable and high yield.
2. Select the time of spraying: The optimal temperature for dressing fertilizer outside the root is 18-25°C, and the absorption effect is better when the humidity is slightly larger. Therefore, it is best to choose a windless cloudy or sunny (dry dew) fertilizer spray, summer and hot weather should be carried out before 10 o'clock or after 16 o'clock. The top-dressing fertilizers are targeted at the early flowering stage, flowering stage, fruiting stage, and the lack of foliar period. What is urgently needed and what to spray is generally sprayed 2-3 times, once every 10-15 days. After 2-3 consecutive shots of trace elements, if the symptoms of deficiency disappear, they do not need to be sprayed. Otherwise, the amount of spraying will be sprayed on wet crowns and leaves (without dripping water) for degrees, and must not be repeatedly sprayed continuously.
3, to determine the best spraying site: leaf back stomata more than green branches, leaves more easily absorb nutrients. In addition to the leaves, the young fruit's absorption capacity is also strong. Outside the roots to the top of the leaves and fruit. Properly and positively, the interior and exterior of the canopy strive to spread evenly and thoughtfully. To improve the spraying effect. Can be added in the fertilizer solution 0.25% -0.5% sugar or 0.01% -0.02% of neutral laundry detergent as an adhering agent. When spraying, it is necessary to make fine particles of the fog so as to make it uniform and dense. The amount of sprayed cloth should be sprayed wet to the branches and leaves (without dripping water). Repeated spraying should not be repeated.
4, rational mixed fertilizers, pesticides: First, the antagonistic effect of nutrients between fertilizers do not mix spray. Such as phosphorus and zinc, iron, copper, boron, potassium and manganese, zinc, calcium, magnesium, calcium and manganese, iron, zinc, boron, etc., mixed spray between these elements will reduce fertility. Second, acid fertilizers can only be mixed with acidic fertilizers and neutral fertilizers, and cannot be mixed with alkaline fertilizers. In order to make the best use of fertilizers, the three elements of nitrogen, phosphorus and potassium are used in the production. Fertilizer mixed with 2-3 kinds of suitable. The types of fertilizers to be mixed should not be excessive and care should be taken to reduce their respective concentrations. Third, the mixed spraying of fertilizers and pesticides must be based on the principle of not reducing the effectiveness of fertilizers, efficacy, and harm to fruit trees. In addition to urea can be sprayed together with any pesticide production, other fertilizers and pesticides mixed spraying, pay attention to acidic fertilizers can not be mixed with alkaline pesticides, alkaline fertilizers can not be mixed with acidic pesticides, biological fertilizers can not be with fungicides, Mixed insecticides, otherwise it will reduce efficacy, fertilizer efficiency, and may even cause phytotoxicity. Regardless of fertilizer spray or mixed spray of pesticides and fertilizers, they must be mixed with existing ones. Do not place them for a long time after mixing to avoid changes. Frequently stir during spraying, stirring while stirring until spraying is complete.
Medical masks are mostly made of one or more layers of nonwoven fabrics. The main production processes include meltblown, spunbond, hot air or needle punching. They are equivalent to resisting liquids, filtering particles and bacteria, and are a kind of medical protection. textile.
The Medical Mask is composed of a mask face and a tightening belt. The mask face is divided into inner, middle and outer layers. The inner layer is skin-friendly (general hygienic gauze or non-woven fabric), and the middle layer is an isolation filter layer (ultra-fine polypropylene Fiber melt-blown material layer), the outer layer is a special material antibacterial layer (non-woven fabric or ultra-thin polypropylene melt-blown material layer).
According to performance characteristics and scope of application, medical masks can be divided into: medical protective masks, medical surgical masks, ordinary medical masks.
1. Medical Protective Mask
Medical protective masks are suitable for the protection of airborne respiratory tract infectious diseases by medical staff and related staff. It is a close-fitting self-priming filter medical protection article with a high protection level, especially suitable for contact with airborne transmission during diagnostic activities Or worn by patients with respiratory infections transmitted by droplets at close range. It can filter the particles in the air, block droplets, blood, body fluids, secretion droplets, etc. It is a disposable product. Medical protective masks can prevent most pathogens such as bacteria and viruses. WHO recommends medical personnel to use protective masks against particles to prevent viral infections in hospital air. .
Medical protective masks comply with GB19083-2003 "Technical Requirements for Medical Protective Masks". Important technical indicators include non-oily particle filtration efficiency and airflow resistance. The specific indicators are as follows: [3]
1) Filtration efficiency: Under the condition of air flow (85 ± 2) L / min, the filtration efficiency of aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 95%, which is in accordance with N95 ( Or FFP2) and above. It can block infectious agents with a diameter of less than 5 μm transmitted by air or close contact with infectious agents transmitted by droplets.
2) Inhalation resistance: under the above flow conditions, the inhalation resistance does not exceed 343.2Pa (35mmH2O).
3) For the samples sprayed on the mask under the pressure of 10.9Kpa (80mmHg), no technical indicators such as penetration should appear on the inside of the mask.
4) The nose mask must be equipped with a nose clip, which is made of bendable plastic material and has a length> 8.5cm.
5) Synthetic blood is sprayed towards the mask sample at a pressure of 10.7kPa (80mmHg), there should be no penetration inside the mask.
2. Medical Surgical Mask
Medical surgical masks are suitable for the basic protection of medical staff or related personnel, as well as the protection against the spread of blood, body fluids and splashes during the invasive operation. The protection level is medium and has certain respiratory protection performance. It is mainly used in clean environments with a cleanliness level of less than 100,000, operating in the operating room, nursing patients with low immune function and performing body cavity puncture and other operations. Medical surgical masks can block most bacteria and some viruses, can prevent medical staff from being infected, and can also prevent the microorganisms carried by medical staff's breath from being directly discharged, posing a threat to patients undergoing surgery. Medical surgical masks require the filtration efficiency of bacteria to be above 95%. Disposable medical surgical masks should also be issued to suspicious respiratory patients to prevent the threat of infection to other hospital personnel and reduce the risk of cross-infection, but to avoid infections that are less effective than medical protective masks. .
It complies with YY0469-2004 "Technical Requirements for Medical Surgical Masks", and important technical indicators include filtration efficiency, bacterial filtration efficiency and respiratory resistance. The specific indicators are as follows:
1) Filtration efficiency: Under the condition of air flow (30 ± 2) L / min, the filtration efficiency of aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 30%.
2) Bacterial filtration efficiency: under specified conditions, the filtration efficiency of Staphylococcus aureus aerosol with an average particle diameter of (3 ± 0.3) μm is not less than 95%; the bacterial filtration rate should be ≥95%; the The filtration rate should be ≥30%.
3) Breathing resistance: Under the condition of filtration efficiency flow, the inhalation resistance does not exceed 49Pa, and the exhalation resistance does not exceed 29.4Pa. When the pressure difference △ P of gas exchange on both sides of the mask is 49Pa / cm, the gas flow rate should be ≥ 264mm / s.
4) Nose clips and mask straps: Nose clips should be provided on the mask. The nose clips are made of plastic materials and the length of the nose clip should be greater than 8.0cm. The mask band should be easy to wear and take, and the breaking strength at the connection point between each mask band and the mask body should be greater than 10N.
5) Synthetic blood penetration: After 2ml of synthetic blood is sprayed at the pressure of 16.0kPa (120mmHg) towards the outer side of the mask, no penetration should occur on the inner side of the mask.
6) Flame retardant performance: The mask material should be made of non-flammable materials, and the mask burns less than 5s after leaving the flame.
7) Residual amount of ethylene oxide: For masks sterilized by ethylene oxide, the residual amount of ethylene oxide should be less than 10μg / g.
8) Skin irritation: The primary irritation index of the mask material should be ≤0.4, and there should be no sensitization reaction.
9) Microbial indicators: total bacterial colonies ≤20CFU / g, and no coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococci and fungi shall be detected.
3. Ordinary medical mask
Ordinary medical masks are used to block spouts exhaled from the oral cavity and nasal cavity, and can be used for one-time hygiene care in ordinary medical environments with the lowest protection level. It is suitable for general hygiene care activities, such as sanitary cleaning, liquid distribution, cleaning bed units, etc., or the blocking or protection of particles other than pathogenic microorganisms such as pollen.
Conforms to the relevant registered product standard (YZB), generally lacks the filtration efficiency requirements for particles and bacteria, or the filtration efficiency requirements for particles and bacteria are lower than medical surgical masks and medical protective masks, only reaching 20.0% for 0.3μm diameter aerosol -25.0% protection effect, can not reach the filtration efficiency of particles and bacteria, can not effectively prevent pathogens from invading through the respiratory tract, can not be used for clinical invasive operations, nor can it protect particles and bacteria and viruses, only limited to dust particles Or aerosol plays a certain mechanical barrier.
Instructions:
1. Carefully cover the mouth and nose with a mask and fasten it to minimize the gap between the face and the mask;
2. Avoid touching the mask when using it-after touching the used mask, for example to remove or clean the mask, wash your hands with soap and water or use alcohol hand sanitizer;
3. After the mask is wet or contaminated with moisture, replace with a new clean and dry mask;
4. Do not reuse disposable masks. Disposable masks should be discarded after each use.
Medical Mask
Medical Mask,Medical Surgical Mask,Disposable Surgical Face Mask,Disposable Non Woven Mask
Guangzhou Aikangli Medical Technology Co., Ltd. , https://www.aikanli.com