(Posted by Tom Fisher.)

For the last 400 years agriculture has been an important component of the Chesapeake Bay watershed. Wheat and other grains in the 1700s and 1800s led to widespread clearing of forests, but poor management practices resulted in soil erosion that left a clear signal in the sediments that is still visible in cores retrieved from the bay. The introduction of European soil conservation methods in the 1800s helped stabilize a denuded landscape, and abundant oysters and submerged grasses cleared the waters.