Why Fertilizer Has Different Efficiency
After fertilizing, the nutrients in fertilizer has gone in four ways: the first is absorbed and employed directly by crops; Second, after decomposed, parts of nutrients volatilized as gas, for example, ammonium bicarbonateis most easily volatilized; Third, every time when it rains heavily, many nutrients run off with water, especially available nitrogen and available potash fertilizer; Fourth, part of nutrients are attached and fixed by soil, unable to be utilized. Fertilizer using efficiency refers to the percentage of nutrient elements absorbed and utilized by current crops from those applied into soil in the total quantity of nutrient elements applied. It varies depending on crops type, fertilizer type, fertilizing amount, fertilizing method, soil type, soil fertility level, etc.
1. Different crops, different utilization rate
Usually, cereal has a low utilization rate for phosphate fertilizer, but legume has a high rate.
2. Different type of fertilizer has different rate of utilization
The loss of organic fertilizer is less than chemical fertilizer, since the efficiency of organic fertilizer is released gradually. In chemical fertilizer, phosphate fertilizer and potash fertilizer has less loss than nitrogen fertilizer.
3. Different Quality of Fertilizer.
It includes fertilizer appearance, content, weight, ingredients, etc. If misused, powdery fertilizer is easier to injure leaves comparing with granulated fertilizer. The reason of calcium superphosphate seedling burning is usually the high content of free acid, trichloracetic aldehyde and trichloroacetic acid. Workmanship defects of slow or controlled-released fertilizer may induce the problems related to nutrient release.
4. Fertilization Time
Just as three meals a day of people, crops need nutrients on time. Other than base fertilizer, timely and proper top dressing according to crops growth demand could give full play to fertilizer efficiency. Most crops has high demand for phosphorus in their seedling stage, and in their later period they need more potassium, so phosphate fertilizer and balanced compound fertilizer are more suitable to be used as base fertilizer, water soluble fertilizer and high potassium compound fertilizer is more suitable for top dressing in later period.
5. Different fertilizing method, different fertilizer using efficiency.
★ The combine use of organic fertilizer and chemical fertilizer has high utilization efficiency. Combined application of elements in chemical fertilizer has obviously high utilization rate than single element.
★ Different application depth, different using efficiency. Concentration placement of phosphorus potassium fertilizer has a high using ratio than surface broadcasting.
★ unreasonable fertilization structure, imbalanced ratio of nitrogen, phosphorus and potassium. Long lack of trace element in soil will affect the output of crops.
★ Too large fertilizing amount poses heavy waste.
6. Different soil moisture content, different utilization rate.
Within certain range of filed moisture capacity, fertilizer using efficiency decreases along with reduce of soil moisture content. However, too much water will cause the leaching of fertilizer, as well as the reduction of fertilizer efficiency. Some nutrients become unavailable for crops because of leaching loss, volatilization or soil fixation.
7. Different fertility, different utilization rate.
Usually, the lower the fertility level, the higher the using efficiency.
Knowing the reasons of differences in fertilizer using efficiency can help us make the most use of fertilizers.