Historical Channel Narrowing and Riparian Vegetation Expansion in the Medicine Lodge River Basin, Kansas, 1871–1983

Abstract

Abstract Remeasurement of selected section line channel crossings from the 1871 first federal land survey of the Medicine Lodge River system in south-central Kansas revealed that channels have narrowed and riparian vegetation density has increased since white European settlement of the area in the early 1870s. Analysis of channel width data, daily precipitation data, aerial photography, tree cores extracted from riparian tree species and of testimony from long-term residents led to the development of a model suggesting that a series of wet years in the 1940s initiated the narrowing and allowed vegetation to stabilize mid-channel and bankside deposits. Precipitation during the 1940s was less seasonal than that during the 1930s, resulting in less variable stream discharge and lower peak discharges during the 1940s. Under this state of altered stream discharge, vegetation was able to become established on mid-channel and point bar deposits. Land use patterns, because they have not changed significantly in th...