As Ann Perry reports:

Wheat farmers in eastern Oregon and Washington who use no-till production systems can substantially stem soil erosion and enhance efforts to protect water quality, according to research by USDA scientists. Agricultural Research Service (ARS) hydrologist John Williams led a study that compared runoff, soil erosion and crop yields in a conventional, intensively tilled winter wheat-fallow system and a no-till 4-year cropping rotation system. ARS is USDA’s chief intramural scientific research agency, and this research supports the USDA mission of promoting sustainable agriculture.

No-till production left the soil surface intact and protected pore space beneath the soil surface, which allowed more water to infiltrate into the subsoil. In addition, there was no significant yield difference between the no-till and conventional till production, and direct seeding in no-till production saved fuel and time.
Read more about this research in the March 2011 issue of Agricultural Research magazine.