Abstract:

To study the effect of long-term reducing fertilization on soil nutrient content in protected cultivated land under different cropping systems, the soil nutrients and fertilization rate of five long-term soil nutrient monitoring points in Jinning County of Kunming City were statistically analyzed, and the effect of different fertilization treatments on soil nutrient was compared. The results showed that there was no significant difference in soil organic matter between long-term reducing fertilizer treatment and conventional fertilizer treatment, but the organic matter in long-term non-fertilization decreased significantly. Compared with those of the fertilization treatment, soil available N and available P of non-fertilization treatment decreased obviously. There was no significant difference in soil available N and available P between reducing fertilizer treatment and conventional fertilizer treatment, but available N decreased as nitrogen fertilizer decreased. Due to the long-term phosphorus fertilizer application, enrichment effect of phosphorus was significant in protected soil. Long-term reducing nitrogen application will not result in the decrease of soil organic matter, available N and available P in protected cultivated land.

Key words: Long Term, Reducing Fertilization, Protected Cultivated Land Soil, Soil Nutrient Content, Kunming