title: Development of a spatially-distributed hydroecological model to simulate cottonwood seedling recruitment along rivers.
abstract: Dam operations have altered flood and flow patterns and prevented successful cottonwood seedling recruitment along many rivers. To guide reservoir flow releases to meet cottonwood recruitment needs, we developed a spatially-distributed, GIS-based model that analyzes the hydrophysical requirements for cottonwood recruitment. These requirements are indicated by five physical parameters: (1) annual peak flow timing relative to the interval of seed dispersal, (2) shear stress, which characterizes disturbance, (3) local stage recession after seedling recruitment, (4) recruitment elevation above base flow stage, and (5) duration of winter flooding, which may contribute to seedling mortality. The model categorizes the potential for cottonwood recruitment in four classes and attributes a suitability value at each individual spatial location. The model accuracy was estimated with an error matrix analysis by comparing simulated and field-observed recruitment success. The overall accuracies of this Spatially-Distributed Cottonwood Recruitment model were 47% for a braided reach and 68% for a meander reach along the Kootenai River in Idaho, USA. Model accuracies increased to 64% and 72%, respectively, when fewer favorability classes were considered. The model predicted areas of similarly favorable recruitment potential for 1997 and 2006, two recent years with successful cottonwood recruitment. This model should provide a useful tool to quantify impacts of human activities and climatic variability on cottonwood recruitment, and to prescribe instream flow regimes for the conservation and restoration of riparian woodlands.
authors.affiliation: Center for Ecohydraulics Research, University of Idaho, 322 E. Front Street, Boise, ID 83702, USA. Electronic address: rohanb@uidaho.edu.
authors.forename: Rohan
authors.initials: R
authors.lastname: Benjankar
authors.affiliation: Inter-Fluve, Hood River, OR 97031, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Burke
authors.affiliation: Center for Ecohydraulics Research, University of Idaho, 322 E. Front Street, Boise, ID 83702, USA.
authors.forename: Elowyn
authors.initials: E
authors.lastname: Yager
authors.affiliation: Center for Ecohydraulics Research, University of Idaho, 322 E. Front Street, Boise, ID 83702, USA.
authors.forename: Daniele
authors.initials: D
authors.lastname: Tonina
authors.affiliation: Environmental Consulting Ltd, Bahnhofstrasse 39, 9020 Klagenfurt, Austria.
authors.forename: Gregory
authors.initials: G
authors.lastname: Egger
authors.affiliation: Department of Biological Sciences, University of Lethbridge, AB T1K 3M4, Canada.
authors.forename: Stewart B
authors.initials: SB
authors.lastname: Rood
authors.affiliation: Kootenai Tribe of Idaho, Bonners Ferry, ID 83805, USA.
authors.forename: Norm
authors.initials: N
authors.lastname: Merz
mesh_terms: D055868:Floods; D017143:Fuzzy Logic; D007061:Idaho; D008954:Models, Biological; D011157:Population Dynamics; D032107:Populus / Q000254:growth & development / Q000502:physiology*; D045483:Rivers; D012621:Seasons; D058614:Seed Dispersal; D036226:Seedlings / Q000254:growth & development / Q000502:physiology; D014872:Water Movements
keywords: Cottonwood; Hydrodynamic model; Hydroecological model; Recruitment; Regulated river; Restoration; Riparian; River management