Comparison of litter dynamics in native and exotic riparian vegetation along the Middle Rio Grande of central New Mexico, U.S.A.

Exotic plants and river regulation have changed riparian ecosystems throughout the south-western U.S. We compared litter dynamics at sites dominated by native cottonwoods or exotic saltcedar in the Middle Rio Grande Valley of central New Mexico. Litter production was greater at cottonwood sites and may have increased after experimental flooding in cottonwood but not in saltcedar. Decomposition was similar for both types of leaves and increased with experimental flooding for both. Forest floor litter was greater at cottonwood sites; litter storage decreased after flooding at the saltcedar site but not at the cottonwood site. Flooding may help reduce the impact of fires by increasing decomposition and reducing the standing stock of forest floor organic matter.