Based on the data of COD emission,GDP and population in Wuhan from 2009 to 2015,the temporal characteristics of COD emission,per capita COD emission and 10 000 yuan GDP COD emission in Wuhan were analyzed,and the environmental learning curve of COD emission in Wuhan was established. The results show that the COD emissions,per capita COD emissions and COD emissions per 10,000 yuan GDP in Wuhan are downward,and the environmental learning curve equation of COD emissions is y = 0.026x - 1.2769 ,and the COD emissions of Wuhan at the end of the 13th Five-Year Plan are about 133 950 tons. Wuhan econo...