流域土地利用与河道生态工程的洪水效应模拟剖析.pptx

Interpretation of High Quality Literarure: The effects of river restorationon catchment scale flood risk and flood hydrologyLian Sun 3/16/2017Copyrights: School of Environment, Beijing Normal Unveisity Published on EARTH SURFACE PROCESSES AND LANDFORMSIn 2016Abstract Background: In the face of challenge of flood risk, a continued reliance on engineered at-a-point flood defenses is seen as both unrealistic and undesirable.Research advances: The contribution of ‘soft engineering’ solutions (e.g. riparian forests, wood in rivers) to integrated, catchment scale flood risk management has been demonstrated at small scales but not larger ones.In this study: we use reduced complexity hydrological modelling to analyze the effects of land use and channel changes resulting from river restoration upon flood flows at the catchment scale.Results: 1 Using engineered logjams(溪流倒木) have highly variable impacts on catchment-scale flood peak.2 The most promising restoration scenarios for flood risk management are for riparian forest restoration at the sub-catchment scale, representing 20 – 40% of the total catchment area, where reductions in peak magnitude of up to 19% are observed through de-synchronization of the timings of sub-catchment flood waves.Floodplain forest:a land cover restorationFloodplain forest and Engineered logjams?Managers restore floodplain morphology and river channel to modify the flood hydrograph(洪水过程线)Principle: the geomorphological configuration of a drainage basin determines the time that it takes for a runoff unit to travel to a point where there is a flood risk. Engineered Logjams (ELJs): a river channel restorationRelative fine in smaller basin,but not clear in larger basin.Require a spatially explicit evaluation of where each intervention is addedFloodplain forest and LogjamsFloodplain forest:a land cover restorationFloodplain forest efficacy: interception, infiltration, slowing conveyance, attenuating runoff, and efficacy increases as the forest ages.H