Figure 10.20
The Chesapeake Bay. (A) Landsat image of the Chesapeake Bay. This estuary was a river valley when sea levels were lower about 15,000 years ago. (B) Most of the original wetlands of the Chesapeake Bay have been developed and are gone. Some, such as these wetlands in the Blackwater National Wildlife Refuge in Maryland, have been preserved.(A. NASA/Goddard Space Flight Center Scientific Visualization Studio; B. © Trevor Clark/Aurora/Getty Images)