The pie charts illustrate The proportion of pollutatns which entered in specific parts of ocean from 7 diffrent source, air, litter, farm waste, industrial waste, marine, offshore oil, domestic sewage, in 1997 and 2007.
Overall, It can be seen that the Most pullutants came from air in both years. It stayed steadily over the time, accounting for around 30 percent. It followed by the portion of marine trash in 1997, while the rate of domestic sewage followed pollutants from air in 2007.
Looking at the graph more closely, It is clear that the domestic sewage and offshore oil increased over the year compared to litter and marine rubbish decreased slightly over the period. Besides, The rate of Industial waste dropped dramatically from 17 percent in 1997 to 9 percent in 2007. It cut by halves throughout the period. Moreover, Other notable feature is the percentage of litter rubbish in 2007, reporting 0 percent.