Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes
The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo’s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment (22.7 km2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns (dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.
KeywordsBank erosion Páramo Fluvial geomorphology Andes
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First and foremost the authors would like to thank the funding sources that supported this research. Those sources include an Oak Ridge Associated Universities Junior Faculty Enhancement Award, an Appalachian State University Board of Trustees International Research Grant, and an Appalachian State University Research Council grant awarded to PI Martin, and a Fulbright Foundation Science and Technology grant awarded to PI Wemple. Additionally, the authors extend sincere thanks to Pablo Arévalo Moscoso of the Universidad Politécnica Salesiana in Cuenca, Ecuador for use of the Biotechnology laboratory facility as well as to Catherine Schloegel, Molly Roske and Stuart White of the Fundación Cordillera Tropical in Cuenca, Ecuador for their granting of access to the research sites, logistical support, and local knowledge. Finally, the authors would like to thank the reviewers for their insightful comments that helped improve the quality of the original manuscript.
- Anderson EP, Marengo J, Villalba R, et al. (2011) Consequences of climate change for ecosystem services in the Tropical Andes. In: Climate Change and Biodiversity in the Tropical Andes. MacArthur Foundation, Inter-American Institute for global Change Research (IAI, Scientific Committee on Problems of the Environment (SCOPE), 1–5.Google Scholar
- Beck W, Isenhart T, Moore P, et al. (2018) Streambank alluvial unit contributions to suspended sediment and total phosphorus loads, Walnut Creek, Iowa, USA. Water 10(2). https://doi.org/10.3390/w10020111
- Crespo P, Célleri R, Buytaert W, et al. (2010) Land use change impacts on the hydrology of wet Andean páramo ecosystems. Proceedings of the Workshop held at Goslar-Hahnenklee, April 2009.Google Scholar
- Eguiguren-Velepucha P, Chamba J, Aguirre Mendoza N, et al. (2016) Tropical ecosystem vulnerability to climate change in southern Ecuador. Tropical Conservation Science 9(4): 1–17.Google Scholar
- Finer M, Jenkins C (2012) Proliferation of hydroelectric dams in the Andean Amazon and implications for Andes-Amazon connectivity. PLoS ONE 7(4). https://doi.org/10.1371/journal.pone.0035126
- Hribljan J, Cooper D, Sueltenfuss J, et al. (2015) Carbon storage and long-term rate of accumulation in high-altitude Andean peatlands of Bolivia. Mires and Peat 15(12):1–14.Google Scholar
- Joslin A, Jepson W (2018) Territory and authority of water fund payments for ecosystem services in Ecuador’s Andes. Geoforum 91:10–20.Google Scholar
- Lyons J, Trimble S, Paine L (2000) Grass versus trees: Managing riparian areas to benefit streams of central North America. Journal of the American Water Resources Association 36(4): 919–930. https://doi.org/10.1111/j.1752-1688.2000.tb04317.x Google Scholar
- Empresa Municipal de Agua Potable de Azogues - EMAPAL (2012) Estudios de factibilidad del componente de agua potable del projecto multifinalitario PUMA, Azogues, pp34.Google Scholar
- Montgomery D, Buffington J (1997) Channel reach morphology in mountain drainage basins. Geological Society of America Bulletin 109(5): 596–611. https://doi.org/10.1130/0016-7606(1997)109<0596:CRMIMD>2.3.CO;2 Google Scholar
- Osborne L, Kovacic D (1993) Riparian vegetated buffer strips in water-quality restoration and stream management. Freshwater Biology 29(2):243–258. https://doi.org/10.1111/j.1365-2427.1993.tb00761.x Google Scholar
- Piégay H, Cuaz M, Javelle E, et al. (1997) Bank erosion management based on geomorphological, ecological and economic criteria on the Galaure River, France. Regulated Rivers-Research & Management 13(5):433-448. https://doi.org/10.1002/(SICI)10991646(199709/10)13:5<433::AID-RRR467>3.0.CO;2-LGoogle Scholar
- Rolando J, Turin C, Ramirez D, et al. (2017) Key ecosystem services and ecological intensification of agriculture in the tropical high-Andean Puna as affected by land-use and climate changes. Agriculture, Ecosystems and Environment 236(2): 221–233. https://doi.org/10.1016/j.agee.2016.12.010 Google Scholar
- Schumm S (1985) Patterns of alluvial rivers. Annual Review of Earth and Planetary Sciences 13(1): 5–27. https://doi.org/10.1146/annurec.ea.13.050185.000253 Google Scholar
- Thorne CR (1981) Field measurements of rates of bank erosion and bank material strength. Erosion and Sediment Transport Measurement: Proceedings of the Florence Symposium, June 1981. IAHS Publ. no. 133.Google Scholar
- Vuille M (2013) Climate Change and water resources in the tropical Andes. Inter-American Development Bank 29.Google Scholar