In the past, farmers often relied on experience to fertilize or put fertilizer per mu, and many times there was often waste, resulting in high fertilizer costs. From the perspective of reducing fertilizer input and improving fertilizer utilization, scientific calculation of fertilizer application can allow farmers to truly save planting costs. Today we introduce the nutrient balance method, how to calculate it?
Nutrient balance method
The basic concept of the nutrient balance method is that the nutrient uptake of a crop is equal to the sum of the nutrient supply of soil and fertilizer. Some of the nutrients provided by fertilizers to crops are fertilized. However, the amount of fertilizer applied to the crop is not exactly the same as the amount of fertilizer nutrients available, because only a portion of the nutrients put into the field are absorbed by the crops in the current season.
Taking into account the fertilizer use efficiency factor, the amount of fertilizer can be estimated by the following formula:
Planned crop fertilization rate (kg) = (total amount of nutrients required for planned yield - soil nutrient supply) / [fertilizer nutrient content × fertilizer use efficiency (%)]
The amount of fertilizer applied to a crop here refers to the amount of a certain nutrient element applied.
Specific to the variety of chemical fertilizers, the amount of physical chemical fertilizers should be estimated by the following formula:
Planned crop fertilizer application amount (kg) = physical fertilizer dosage (kg) × active ingredient content (%)
In the above two formulas:
1. The total amount of nutrients required for the planned yield kg) = (planned yield / 100) × the number of nutrients required for each 100kg of yield (refer to the approximate number of nutrients required for the formation of 100kg of economic yield of different crops).
The planned yield is an additional 10-15% increase in the three-year average yield of local crops.
2. Soil nutrient supply (kg) = (yield in non-fertilizer area/100) × amount of nutrients required for each 100kg yield formed
Soil fertilizer supply is generally estimated by soil sampling tests. In the absence of laboratory conditions, it is also possible to estimate the yield without fertilization (blank yield).
3. In general, the seasonal utilization rate of chemical fertilizer is: nitrogen fertilizer 30%-35%, phosphate fertilizer 20%-25%, potassium fertilizer 25%-35%.