Riverine transport is the principal pathway of dissolved elements from land to the sea.Based on the quantitative analysis of human effects on the phosphorus cycling within the Yangtze River basin, we estimated the exports of dissolved inoiganic phosphorous (DIP) from the Yangtze River to the estuary for the period 1970-2003, by using the Global NEWS-DIP model.Modeled DIP export increased from 2.45kg/km² in 1970 to 14.05kg/km² in 2003 under the enhancing anthropogenic activities.No significant difference between the modeled and measured values at the level of P=0.05 is observed, and the average model error is 12.29%.Diffuse sources (including chemical fertilizer application and animal manure P input) had contributed the most in DIP export since 1993.The contribution varied between 58.60% and 75.48%.Sewage discharge was the major source of river DIP export before 1993, with the contribution varying between 99.98% and 45.21%, while the contribution decreased rapidly since then until to 24.81% in 2003.We also discussed possible future trajectories of DIP export based on the MEA scenarios.How to control the diffuse nutrient inputs under enhancing human pressures will be a long-term and urgent task.