Dynamic processes and ecological restoration of hyporheic layer in riparian zone

Hyporheic layer of riparian zone is an active transition zone and ecotone between river and groundwater in riparian zone, which can be denoted respectively from hydrogeography, ecology and environment. Due to its unique structure properties in vertical, lateral and longitudinal directions, hyporheic layer of riparian zone was characterized to have some edge-effects and dynamic processes, including flow dynamics, ecological and chemical processes, which were driven by interactions among sediments, flow, communities, organic matters, solutes and environmental factors. As the three dynamic processes have affected each other and ecological and chemical processes have depended on flow dynamics driving and oxygen concentration, it has resulted that hyporheic layer in riparian zone could have stored floods and supplied suitable habitats and removed pollution. However, some of these functions were being weakened due to human and natural actions. In order to conserve the ecological balance and keep the sustainable development in riparian zone, it should be necessary to diagnose health status and verify weakening mechanism and practice ecological restoration. In future, according to the complex properties of riparian zones in our countries, it should be very important to investigate the responses of the hydrological, heat transportation, biochemical and ecological mechanisms to variation of hydrology, geomorphology, permeability, vegetation and riparian construction, and quantify the range of hyporheic layer and design the ecological restoration.