The Relationship Between Weather Conditions and Fertilization, and Fertilization Forecasting Methods Based on Weather Conditions

The growth of crops and the effects of fertilization are closely related to weather conditions. Light affects crop photosynthesis, and the product of photosynthesis——sugar, is the energy source supplied for root respiration. Insufficient energy will affect the roots' absorption of nutrients.

Therefore, under conditions of insufficient light, the absorption of elements such as nitrogen, phosphorus, potassium, calcium, magnesium, zinc and manganese is significantly reduced. Temperature affects both the transformation of fertilizers in the soil and the absorption of nutrients by crop roots. For example, rice in mountainous areas is often irrigated with low-temperature water, making it prone to rice blast disease, which is caused by low temperatures affecting the rice's absorption of silicon and potassium. Water, on the one hand, can accelerate the dissolution of fertilizers and promote crop absorption of nutrients; on the other hand, if there is too much water, not only is soil aeration poor, which is unfavorable for crop absorption of nutrients, but it also causes nutrient loss. Therefore, fertilization should not be carried out on rainy days. On sunny days, the fertilization concentration should also be determined according to soil moisture conditions. If the soil is wet, fertilizer can be used at a higher concentration; if the soil is dry, fertilizer should be diluted before application.

In long-term production practice, people have summarized fertilization forecasts based on weather conditions for possible nutrient deficiency symptoms in crops. For example, in years with low temperatures in early spring, rice is prone to phosphorus and zinc deficiency, so attention should be paid to the use of phosphate fertilizer or zinc fertilizer; under conditions of insufficient light, potassium fertilizer should be applied more to improve the crops' utilization of light energy; in dry years, rapeseed is prone to boron deficiency, and vegetables (Chinese cabbage, radish, etc.) are prone to calcium deficiency, so attention should be paid to the use of boron fertilizer and calcium fertilizer; in rainy seasons, available iron in the soil is easily leached out, and fruit trees often show iron deficiency symptoms.