Objectives Over the past 25 years, agricultural technology has advanced rapidly. Studying changes in fertilizer application rates, yield, nutrient uptake and fertilizer use efficiency of rice in Heilongjiang Province can provide technical support and theoretical basis for improving fertilizer efficiency.

Methods A total of 255 rice field experiment data between 1999 to 2023 were collected, and the fertilizer application rate, yield, nutrient uptake, and fertilizer use efficiency data were extracted from 5 treatments like CK, NP, NK, PK and NPK. Each 5-year period was designated as a stage (Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ). A total of 1130 sets of data on fertilizer application rates, yields, nutrient uptake, and fertilizer use efficiency for each treatment were compiled. Temporal trends in rice yields and fertilizer use efficiency in Heilongjiang Province, as well as their driving factors were analyzed.

Results From 1999 to 2023, rice yield under NPK treatment in Heilongjiang Province showed a fluctuating but overall upward trend, averaging 8434 kg/hm² annually with an average yearly increase of 1.6%. Compared with NPK, the yields in PK, NK, NP and CK treatments were reduced by 37.0%, 15.1%, 13.7% and 38.0% respectively (P<0.05). Fertilizer application rate of rice demonstrated a slightly fluctuating upward trend. The average fertilization rates of N, P₂O₅ and K₂O were 137.2, 66.5 and 78.4 kg/hm² respectively, with annual average increases of 1.8%, 2.2% and 2.0% respectively; the economic optimal fertilization rates for rice were N 133.9, P₂O₅ 63.7, K₂O 74.2 kg/hm², with the ratio of N∶P₂O₅∶K₂O at 2.1∶1∶1.2. The uptake amounts of N, P and K nutrients in rice under NPK treatment showed a slightly fluctuating upward trend. The average uptake of N, P₂O₅ and K₂O was 133.1, 55.3 and 127.1 kg/hm², with an average annual increase of 2.4%. 2.6% and 1.7%, respectively; while nutrient uptake of rice plants in PK, NK, NP and CK treatments were significantly reduced, relative to NPK treatment. Yield of rice was positively (P<0.05) correlated with the uptake of N, P and K by the plants, and the degree of correlation was N>P>K. Nutrient recovery rates, agronomic efficiency and partial productivity of N, P and K in rice showed a slightly fluctuating upward trend. Average N recovery efficiency, agronomic efficiency, and partial productivity of nitrogen fertilizer were 37.6%, 25.8 kg/kg, and 66.1 kg/kg respectively, with an average annual increase of 0.3%, 2.6%, and 0.1%, respectively. For P fertilizer, the corresponding values were 25.0%, 32.7 kg/kg, and 135.4 kg/kg, respectively, with annual average increases of 0.4%, 2.9%, and 1.5%, respectively; and for K fertilizer, they were 46.1%, 24.2 kg/kg, and 115.9 kg/kg respectively, with an average annual increase of 0.7%, 3.8%, and 1.8% respectively.

Conclusions Over the past 25 years, rice yield, fertilizer application rate, nutrient uptake amount and fertilizer use efficiency in Heilongjiang Province have all increased with fluctuations, the optimal economic fertilization rates stand at N 133.9, P₂O₅ 63.7and K₂O 74.2 kg/hm², maintaining a ratio of N∶P₂O₅∶K₂O at 2.1∶1∶1.2. Increased fertilizer application rate, enhanced nutrient uptake, and improved fertilizer use efficiency have been the key factors contributing to the increase in rice production.