The study looked at how different types of fertilizer affect the loss of nitrogen and phosphorus in water from paddy fields, as well as grain production. They found that reducing nitrogen fertilizer alone lowered the risk of nitrogen loss, but when combined with biomass carbon, it increased grain production by 24.6%. However, this combination also raised the risk of phosphorus loss in the water. The best time to control nitrogen and phosphorus loss is within a week after fertilization, as heavy rain during this time can lead to runoff and loss of these nutrients.