Nitrates Evaluation in the National Térraba-Sierpe Wetland

Keywords: nitrates, wetlands, sustainable agriculture, ecological impacts, National Térraba-Sierpe Wetland


This research aimed to describe, spatially and temporally, the concentrations of nitrates in correlation with anthropogenic activities surrounding the Sierpe River that crosses the National Térraba-Sierpe Wetland (HNTS). Although territorially protected by Costa Rican legislation, this wetland is surrounded by intense agricultural activity. In 2018, monthly monitoring of pH, nitrates, and dissolved oxygen was carried out in fourteen points of the river. A baseline around 5 mg NO3- / L was obtained in periods without agricultural activities and peaks up to 20 mg NO3- / L after fertilization activities. Correspondingly, a decrease in dissolved oxygen and pH was observed on days of high agricultural activity. In the months following fertilization, accelerated growth of aquatic plants and a general deterioration in mangrove reproduction were observed by collaborators of the HNTS management and surveillance program. Nevertheless, when high nitrates concentration in agricultural areas are observed,  their decline is also observed in the direction of the river's flow until it reaches its mouth.  This facts shows the still active function of the wetland and its importance in the processing of nitrates. To regulate activities not only in the territorial limit but also in the limits of the water system surrounding the HNTS is recommended to protect this ecosystem function.


Audet, J., Baattrup-Pedersen, A., Andersen, H. E., Andersen, P. M., Hoffmann, C. C., Kjaergaard, C., & Kronvang, B. (2015). Environmental controls of plant species richness in riparian wetlands: Implications for restoration. Basic and Applied Ecology, 16(6), 480–489.
Austin, A. T., Bustamante, M. M. C., Nardoto, G. B., Mitre, S. K., Pérez, T., Ometto, J. P. H. B., … Martinelli, L. A. (2013). Latin America’s Nitrogen Challenge. Science, 340(6129), 149.
Canfield, D. E., Glazer, A. N., & Falkowski, P. G. (2010). REVIEW The Evolution and Future of Earth’s Nitrogen Cycle. Science, 330, 192–196.
Devol, A. H. (2015). Denitrification, Anammox, and N 2 Production in Marine Sediments. Annual Review of Marine Science, 7(1), 403–423.
Dislich, C., Keyel, A. C., Salecker, J., Kisel, Y., Meyer, K. M., Auliya, M., … Wiegand, K. (2017). A review of the ecosystem functions in oil palm plantations, using forests as a reference system. Biological Reviews, 92(3), 1539–1569.
Fennel, K., & Testa, J. M. (2019). Biogeochemical Controls on Coastal Hypoxia. Annual Review of Marine Science, 11(1), 105–130.
Fisher, J., & Acreman, M. C. (2004). Wetland nutrient removal : a review of the Wetland nutrient removal: a review of the evidence. Hydrology and Earch System Sciences, 8(4), 673–685.
Fowler, D., Coyle, M., Skiba, U., Sutton, M. A., Cape, J. N., Reis, S., Sheppard, L.J., Jenkins, A., Grizzetti, B. Galloway, J. N. Vitousek, P., Leach, A. Bouwman, A.F., Butterbach-Bahi, K., Dentener, F., Stevenson, D., Amann, M. & Voss, M. (2013). The global nitrogen cycle in the twenty-first century. Philosophical Transactions of the Royal Society B: Biological Sciences, 368(1621), 20130164.
Gallmetzer, N., & Schulze, C. H. (2015). Impact of oil palm agriculture on understory amphibians and reptiles: A Mesoamerican perspective. Global Ecology and Conservation, 4, 95–109.
Galloway, J. N., Townsend, A. R., Erisman, J. W., Bekunda, M., Cai, Z., Freney, J. R., … Sutton, M. A. (2008). Transformation of the nitrogen cycle: Recent trends, questions, and potential solutions. Science, 320(5878), 889–892.
Gilmore, K. L., Doubleday, Z. A., & Gillanders, B. M. (2019). Prolonged exposure to low oxygen improves hypoxia tolerance in a freshwater fish. Conservation Physiology, 7(1), 1–10.
Hansen, A. T., Dolph, C. L., & Finlay, J. C. (2016). Do wetlands enhance downstream denitrification in agricultural landscapes? Ecosphere, 7(10).
Hernández-Alpízar, L., Mora-Molina, J., & Coy-Herrera, R. (2020). Monitoreo de nitratos en los drenajes de palma aceitera (Elaeis guineensis): una herramienta para la sostenibilidad del cultivo, UNED Research Journal, 12(1). Retrieved from
Hernández-Alpízar, L. & Coy-Herrera, R. (2019). Dispositivo y método de calibración interpolativo en análisis cuantitativo de flujo continuo. CR20180476 (A).
Johnson, M. W., Powers, S. P., Senne, J., & Park, K. (2009). Assessing in Situ Tolerances of Eastern Oysters (Crassostrea virginica) Under Moderate Hypoxic Regimes: Implications for Restoration. Journal of Shellfish Research, 28(2), 185–192.
Khatun, R., Reza, M. I. H., Moniruzzaman, M., & Yaakob, Z. (2017). Sustainable oil palm industry: The possibilities. Renewable and Sustainable Energy Reviews, 76(August 2016), 608–619.
Olivares, J., Bedmar, E. J., & Sanjuán, J. (2013). Biological Nitrogen Fixation in the Context of Global Change. Molecular Plant-Microbe Interactions, 26(5), 486–494.
U.S. EPA. (2002). Methods for Evaluating Wetland Condition: Study Design for MonitoringWetlands. Office of Water, U.S. Environmental Protection Agency, Washington, DC.EPA-822-R-02-015. Retrieved from
Pirker, J., Mosnier, A., Kraxner, F., Havlík, P., & Obersteiner, M. (2016). What are the limits to oil palm expansion? Global Environmental Change, 40, 73–81.
Srinivas, A., & Koh, L. P. (2016). Oil palm expansion drives avifaunal decline in the Pucallpa region of Peruvian Amazonia. Global Ecology and Conservation, 7, 183–200.
Sutton, M. A., Reis, S., Billen, G., Cellier, P., Erisman, J. W., Mosier, A. R., … Skiba, U. (2012). Preface: ""Nitrogen & global change"." Biogeosciences, 9(5), 1691–1693.
Taylor, P. G., & Townsend, A. R. (2010). Stoichiometric control of organic carbon-nitrate relationships from soils to the sea. Nature, 464(7292), 1178–1181.
Taylor, P. G., Wieder, W. R., Weintraub, S., Cohen, S., Cory, C., Townsend, A. R., … Townsend, A. R. (2018). Organic forms dominate hydrologic nitrogen export from a lowland tropical watershed Published by : Wiley on behalf of the Ecological Society of America Stable URL : Organic forms dominate hydrologie nitrogen export fro, 96(5), 1229–1241.
Walsh, R. P. D., Nainar, A., Bidin, K., Higton, S., Annammala, K. V, Blake, W., … Hanapi, J. (2016). Hydrogeomorphological and water quality impacts of oil palm conversion and logging in Sabah, Malaysian Borneo: a multi-catchment approach. Geophysical Research Abstracts, 18(4), EGU2016-18195.
Weintraub, S. R., Taylor, P. G., Porder, S., Cleveland, C. C., Asner, G. P., Townsend, A. R., … Townsend, A. R. (2018). Topographic controls on soil nitrogen availability in a lowland tropical forest. Wiley on behalf of the Ecological Society of America Stable Topographic controls on soil nitrogen availability in a l, 96(6), 1561–1574.
How to Cite
Hernández-Alpízar, L., & Mora-Molina, J. (2022). Nitrates Evaluation in the National Térraba-Sierpe Wetland. Uniciencia, 36(1), 1-11.
Original scientific papers (evaluated by academic peers)

Comentarios (ver términos de uso)