A methodology to quantify the potential of urban rivers to provide ecosystem services based on remote sensing and field indicators – The Pochote River, Nicaragua

Natural rivers in urban areas bear significant potential to provide ecosystem services for surrounding inhabitants. However, surface sealing by houses and street networks, urban drainage, disposal of waste and wastewater resulting from advancing urbanization usually leads to deterioration of urban rivers and their riparian areas. This ultimately leads to the loss of ecosystem service provision. This contribution presents an innovative methodology for a rapid and low-cost assessment of the ecological status of urban rivers and riparian areas in developing countries under data scarcity conditions. The methodology uses a combination of low-cost field data and freely available high resolution satellite images to assess three ecological status categories: river hydromorphology, water quality and riparian land cover. The focus here is on the assessment of proxies for biophysical structures and processes representing ecological functioning that enable urban rivers and riparian areas to provide ecosystem services. These proxies represent a combination of remote sensing land cover/land use-based and field-based indicators. Finally, the three ecological status categories are combined to quantify the potential of 100 m long river sections to provide regulating ecosystem service. The development and application of the methodology is demonstrated on the case study of the Pochote River in the City of León, Nicaragua. The potential to provide a set of different regulating ecosystem services is then visualized for each 100 m section of the river. This spatially distributed information of urban river ecosystem service potential of individual sections of the urban river and riparian areas can serve as an important information for decision making considering the protection, future use and city development of these areas as well as the targeted and tailor-made development of nature-based solutions such as green infrastructure