A study looked at how different fertilizers affect soil nutrition and crop yield over 18 years. They found that using fertilizers can increase organic matter, available phosphorus, and available potassium in the soil. Crop rotation and succession also play a role in soil nutrition changes. Applying manure had the biggest impact on crop yield, increasing it by 118.7% to 175.8% compared to no fertilizer. Organic manure was more effective than chemical fertilizer or crop straw. Not using any fertilizer for a long time can lower crop yield. Overall, using organic manure is the best way to improve soil nutrition and crop yield.