Lag in stream channel adjustment to livestock exclosure, White Mountains, California
Authors: G. M. Kondolf
Journal: Restoration Ecology
Summary of Methods: Riparian area recovery from grazing was measured along the North Fork of Cottonwood Creek in Inyo National Forest, California. The indicator of recovery was channel width and vegetation height after 24 years of livestock exclusion compared to areas still being grazed. The exclosure was constructed in 1967 and the study took place in September 1991. Areas outside the exclosure were annually grazed by 200 cattle for one to two months. Stream channel width and vegetation height were measured at eight cross sections within the exclosure and seven cross sections downstream of the exclosure.
Article Summary / Main Points: There were no differences in channel width inside and outside of the exclosure. However, vegetation height was much shorter outside of the exclosure. Channel width similarities were unexpected and could be due to the lack of time for recovery and high flows to deposit sediment.
Vegetation Types: Riparian and Wetlands
Article Review Type: Refereed
Article Type: Documented Case History
Keywords: channel morphology, inyo national forest, streambank vegetation, grazing impacts, stream channel width, revegetation, streambank recovery
Annotation: This study has interesting results, but without more stream channels included in the study it is hard to rely on the findings. Stream type or class would also change how livestock exclusion affects riparian recovery. In addition to the authors’ explanation of channel width similarities inside and outside the exclosure, the inside of the exclosure could have crossed a threshold and reached a new steady state where the channel width cannot shrink without major environmental influences or management.