Get reliable rangeland science

The Lower Owens River was diverted into the Los Angeles Aqueduct in 1913 leaving the majority of the 62 mile river channel devoid of flowing surface water for 93 years.� Since 2006, controlled flows have been released into the river channel as part of the Lower Owens River Project. �Livestock utilization limits were also implemented along the riparian corridor beginning in 2006.� Long term trend transects were established on the adjacent moist floodplain sampling plant frequency and shrub cover.� The principle objectives for the trend monitoring program were to monitor vegetation community response with the return of flows and track long term livestock grazing impacts on these sites. The majority of transects had been consistently read for the past 14 years.�� Twelve of the 46 transects were situated in the former �dry reach� of the river which lacked perennial surface flow for 93 years. The remaining 34 transects were located in river sections that had received a minimal, continual flow beginning in the 1980�s or received water from spring flow.� Long term monitoring results documented two distinct trajectories. �Portions of the river which historically received some water developed into larger grass dominated meadows whereas the �dry reach� portions developed communities populated by Atriplex torreyi and Bassia hyssopifolia.� �The absence of coincident meadow development was likely caused by dissimilar successional starting points between the two sites.� In this case more time may be required for meadow development in the �dry reach�.� Other factors that may be driving trajectories of the two communities are channel development, depth to groundwater, historical and current disturbance regimes.