Quantification of potential flood inundation areas in the marsh wetland of Honghe National Natural Reserve, Northeast China

Wetland protection and recovery needs scientific foundations for a better understanding of wetland floods, since the flooding existence and its dynamics are the key aspects in the formation and evolution of wetland ecosystems. The Honghe National Natural Reserve (HNNR) in the Northeast China has been listed in the Ramsar Convention on Wetlands since 2002. The specific dates for determining of an average inundation boundary caused by a regular flooding were firstly fixed from multiple rainfall events by a hydro-meteorological analysis based on the long-term rainfall data. The flood inundation areas in the HNNR marshes were mapped according to the correlation between hydro-geomorphology and regular flood progress. The mapping of the flood inundation areas were supported technically from the application of remote sensing images, combining the hydro-geomorphologic analysis with meteorological statistical data. The final map with the spatial-temporal content of an inundation created by hydro-geomorphological analysis and remote sensing data was validated by the long-term rainfall, soil moisture and surface water level data in the HNNR. The results indicated that the flood inundation areas were mainly distributed in large patches along the two main river courses of Nongjiang River and its branch of Woyalan River in the northern and central HNNR. The flood inundation patches were scattered as seasonal marshes and permanent ponds in the southern and eastern HNNR. The extracted flood inundation area accounted for more than a quarter of the total area of HNNR. The flood inundation area of Nongjiang was much larger than that of Wuyalan. (C) 2018 European Regional Centre for Ecohydrology of the Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.