Changing landscapes of the middle Rio Grande
Product Type:Book, Pages in
Suggested Citation:Bogan, M.A. 1998. Changing landscapes of the middle Rio Grande. In: Status and trends of the nation's biological resources: vol. 2. Washington, D.C.: U.S. Geological Survey. 562-563.
Before the fourteenth century, the Rio Grande between Cochiti and San Marcial, New Mexico, was a perennially flowing, sinuous, and braided river (Crawford et al. 1993). The river migrated freely over the floodplain, limited only by valley terraces and bedrock outcroppings; this shifting of the river created ephemeral mosaics of riparian vegetation (forests and shrublands) and wetlands (ponds, marshes, wet meadows) (Durkin et al. 1995). Water diversion for irrigated agriculture by Native Americans and later by European immigrants may have somewhat diminished river flows during drowning season before 1900. Increased sediment loading, the result of climatic variations and agriculture, caused the river’s channel to become broader and shallower, which increased the river’s tendency to flood.