A Geomorphic Characterization Of An Ecuadorian Páramo River

The páramo describes a neo-tropical alpine grassland located between the permanent tree and snowline in the northern Andes of South America. Millions of people in the northern Andes are dependent upon the páramo for ecosystem services. The páramo serves as the principal supply of freshwater as well as hydropower generation and is an important headwater region of the Amazon River. Little is known about the hydro-geomorphic characteristics of these river systems that are increasingly being impacted by human use. The objectives of this research are to characterize the geomorphology of the Ningar River, a headwater stream in the Amazon basin that drains a 14.52 km2 páramo watershed in the Central Cordillera of south central Ecuador. This includes establishing hydraulic geometry and stream power relationships derived from topographic surveys and pebble count data, and a subsequent global comparison with other, previously studied mountain river systems. Results suggest that páramo streams exhibit similar hydro-geomorphic characteristics as other mountain systems, as well as grassland and plains areas, likely because ample sediment supply in lower slope reaches in the form of páramo soils. Constructing dams in this environment could disrupt the important geochemical connection between the páramo and downriver ecosystems, such as the Amazon.