The study aimed to find the best fertilizer amounts for winter wheat in Northern China's cinnamon soil. By testing soil and fertilizer in multiple locations and years, researchers calculated the nutrients wheat needs and how well the soil provides them. They found that wheat needs 3 kg of nitrogen, 1.2 kg of phosphorous, and 2.8 kg of potassium per 100 kg of grain. The amount of available nutrients in the soil affects how well plants use them. By using a balanced nutrient approach, researchers created a system to recommend the right fertilizer amounts for wheat production in the region.