Tamarix Species (Salt Cedar) Stem Density Along Fluvial and Salinity Gradients on the Salt Plains National Wildlife Refuge

Abstract

Invasive species and river alteration have major impacts on riparian ecosytems. I have examined density patterns of the invasive species Tamarix in relation to soil salinity patterns along a gradient at the transition from the salt flats to the vegetation zone during a two-year study period. These data were related to local precipitation and reservoir release records. In the vast majority of quadrats, Tamarix live and dead stem densities decreased from 2006 to 2007, while species richness increased. Tamarix density decrease in 2007 may have reduced competition, allowing an increaes in many other species. it is plausible that flooding in 2007 reduced Tamarix stem density in my study. However, due to the high spatial and temporal variability in soil salinity, effects of salinity are less obvious.