At present, a considerable portion of the marketed compound fertilizers do not meet the national DB15063-94 standard. National standards stipulate that the effective nutrient content of compound fertilizer (composite fertilizer), the total concentration of high-concentration NPK ≥40%, the low concentration of NPK ≥25%, excluding trace elements and medium elements; water-soluble phosphorus content ≥ 40%, the water molecule content is less than 5%; the particle size is 1 to 4.75 mm. Therefore, in addition to looking at the trademark and nutrient content when purchasing compound fertilizer, it is also necessary to pay attention to the manufacturer and the place of origin. In addition, there are two kinds of potassium in the compound fertilizer, one is potassium chloride and the other is potassium sulfate. Potassium chloride contains chlorine, which is not suitable for chlorine-free crops. Where there is no "S" symbol on the composite fertilizer bag, the potassium is potassium chloride, and the chlorine crops such as grapes, potatoes, tobacco, beets, etc. must not be applied. The fertilizer bag must be marked with the "S" symbol. Compound fertilizer, a compound fertilizer composed of potassium sulfate.
Second, scientific selection of compound fertilizer according to crop varieties
Generally, the field crops use NPK compound fertilizer, wheat high-yield fields should use NPK ternary compound fertilizer; wheat, rice, millet and other close crops, suitable for powder compound fertilizer; thin planting crops such as corn should use granular Compound fertilizer; vegetables, especially fruit and vegetables, root vegetables and fruit trees, etc. need more cash crops, should use NPK compound fertilizer with higher potassium and low nitrogen.
Third, according to soil properties, scientific selection of compound fertilizer
For soils with slightly alkaline and low organic matter content (the soil pH is generally around 8.0) and effective nitrogen and phosphorus deficiency, acidic compound fertilizers such as monoammonium phosphate or humic acid NPK fertilizers and nitrogen and phosphorus should generally be used. Compound fertilizer is appropriate. However, for a small number of red clay or acid brown loam, alkaline compound fertilizers such as diammonium phosphate should be used.
4. Selecting compound fertilizer scientifically according to fertilization method
In order to improve the fertilizer efficiency of the compound fertilizer, different application methods should be selected for different dosage forms of compound fertilizer. Granular compound fertilizer must be used as base fertilizer, and the higher the hardness of the pellet, the better the fertilizer. The compound fertilizer composed of ammonium nitrogen in the compound fertilizer is beneficial to increase the utilization rate of nitrogen. For topdressing application, powdered compound fertilizer should be used, and it should be noted that the water-soluble phosphorus content in the compound fertilizer should be greater than 40%, and the nitrogen compound is composed of ammonium nitrogen and nitrate nitrogen. should. Generally, the effect of humic acid compound fertilizer is better than the effect of topdressing.
We supply various down light, including recessed down light, surface mounted downlight, small led downlights etc.
The below information will help you to know more about down light.
What are downlights?
A Downlight is a light placed or designed to throw illumination downwards, concentrating the light in a downward direction.
What is the difference between downlight and ceiling light?
The difference between downlights and ceiling mounted lights are how they are installed into the roof. Both are mostly flush mounted against the ceiling with a hole to install the light, downlights requiring a larger hole.
Which rooms should have downlights?
Downlights are often used as spotlights or used in areas where you need an additional amount of light for task illumination. They're one of the most popular types of ceiling lights in kitchens as a way to light up countertops and work surfaces. They're also great for general ambient lighting in larger rooms.
Down light is suitable for commercial and residential spaces, can be installed in a multitude of commercial and residential spaces needing vibrant lighting including bedrooms, kitchens, living rooms, office spaces, hotels, retail stores, and more!
Down Light ,Recessed Downlight,Bathroom Downlights, surface mounted downlight
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