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Water, Energy, and Biogeochemical Budgets Program: Luquillo Mountains, Puerto Rico


The USGS Water, Energy, and Biogeochemical Budgets (WEBB) project performs research at 5 sites across the U.S., in ecosystems ranging from tropical rainforest to alpine tundra. The WEBB project strives to conduct innovative, interdisciplinary research that will improve our understanding of processes controlling the exchange of water, energy, and solutes between atmospheric, terrestrial, and aquatic environments. The WEBB program uses the "small watershed approach," in which water and chemical inputs in precipitation and outputs in streamwater are accurately measured. Focused study in a small watershed makes it easier to identify patterns, trends, and processes by which chemicals - including pollutants - move from the land to streams. Results are then extrapolated to the larger landscape and help inform the government, land managers, and the public on issues facing water supplies and biological resources.

Our research focuses on three themes:

The Luquillo WEBB Project is set in a mountainous, humid-tropical environment in and adjacent to the El Yunque National Forest in eastern Puerto Rico. Since 1991, WEBB researchers here have studied the effects of geology, land use, atmospheric pollution, drought, and rainfall patterns on hydrology, water quality, and landslide events. We continue to monitor streamflow, water quality, and stable isotopes to better understand how rainfall becomes streamflow, how its chemistry changes along the way, and how the system may be affected by climate change in the future. The Luquillo WEBB site anchors the low-latitude end of the climatic gradient of the WEBB program; it also provides information that is applicable to other tropical watersheds around the world.

See the locations page for more information on WEBB sites.

Contact Information

Sheila Murphy
Site Coordinator and Project Scientist
USGS National Research Program
sfmurphy@usgs.gov
https://profile.usgs.gov/sfmurphy

Angel Torres
Fieldwork Coordinator
USGS Caribbean Water Science Center
ajtorres@usgs.gov

Manuel Rosario
Technician
USGS Caribbean Water Science Center
mrosario@usgs.gov

Martha Scholl
Project Scientist
USGS National Research Program
mascholl@usgs.gov
https://profile.usgs.gov/mascholl

Jamie Shanley
Project Scientist
USGS New Hampshire-Vermont Water Science Center
jshanley@usgs.gov

Related Sites

Luquillo Critical Zone Observatory

Luquillo LTER

USGS Caribbean Water Science Center

Water, Energy, and Biogeochemical Budgets (WEBB) Program

Luquillo Project Publications

YearCitation
1995Brown, E.T., Stallard, R.F., Larsen, M.C., Raiseck, G.M., and Yiou, F. 1995, Denudation rates determined from the accumulation of in situ produced 10Be in the Luquillo Experimental Forest: Puerto Rico: Earth and Planetary Science Letters, vol. 129, p. 193-202.
1998Brown, E. T., Stallard, R. F., Larsen, M. C., Bourlès, D. L., Raisbeck, G. M., and Yiou, F., 1998, Determination of predevelopment denudation rates of an agricultural watershed (Cayaguás River, Puerto Rico) using in situ-produced 10Be in river-borne quartz: Earth and Planetary Sciences Letters, v. 160, p. 723-728.
2004Buss H.L., Sak P.B., White A.F., and Brantley S.L., 2004, Mineral dissolution at the granite-saprolite interface, in Wanty, R.B., and Seal, R.R. II, editors, Proceedings of the 11th International Symposium on Water-Rock Interaction, Taylor and Francis, the Netherlands, p. 819-823.
2005Buss H.L., Bruns M.A., Schultz M.J., Moore J., Mathur C.F., and Brantley S.L., 2005, The coupling of biological iron cycling and mineral weathering during saprolite formation, Luquillo Mountains, Puerto Rico. Geobiology, 3, 247-260.
2006Buss H.L., 2006, Biogeochemical Weathering of Iron-Silicate Minerals, Ph.D. Thesis, The Pennsylvania State University, 203 pp.
2008Buss H.L., Sak P.B., Webb S.M., and Brantley S.L., 2008, Weathering of the Rio Blanco quartz diorite, Luquillo Mountains, Puerto Rico: Coupling oxidation, dissolution, and fracturing. Geochimica et Cosmochimica Acta, 72, 4488-4507.
2010Buss H.L., Mathur R., White A.F., and Brantley S.L., 2010, Iron and phosphorus cycling in deep saprolite, Luquillo Mountains, Puerto Rico. Chemical Geology 269, 52-61.
2001Carter, L.M., Shea, E., Hamnett, M., Anderson, C., Dolcemascolo, G., Guard, C., Taylor, M., Barnston, T, He, Y., Larsen, M.C., Loope, L., Malone, L., and Meehl, M., 2001, Potential consequences of climate variability and change for the US-affiliated islands of the Pacific and Caribbean: Chapter 11, p. 315-349 in: The Potential Consequences of Climate Variability and Change: Foundation Report, Report by the National Assessment Synthesis Team for the US Global Change Research Program, Cambridge University Press, Cambridge, UK, 620p.
2006Derry L. A., Pett-Ridge J. C., Kurtz A. C., Troester J., 2006, Ge/Si and 87Sr/86Sr tracers of weathering reactions and hydrologic pathways in a tropical granitoid system: Journal of Geochemical Exploration 88, 271-274.
2006Fletcher R.C., Buss H.L., and Brantley S.L., 2006, A spheroidal weathering model coupling porewater chemistry to soil thicknesses during steady state erosion: Earth and Planetary Science Letters, 244, 444-457.
2009Glynn P.D., Larsen M.C., Greene E.A., Buss H.L., Clow D.W., Hunt R.J., Mast M.A., Murphy S.F., Peters N.E., Sebestyen S.D., Shanley J.B., and Walker J.F. (2009) Selected achievements, science directions, and new opportunities for the WEBB small watershed research program. In: Planning for an Uncertain Future—Monitoring, Integration, and Adaptation, Webb, R.M.T., and Semmens, D.J., eds., U.S. Geological Survey Special Investigations Report 2009-5049, 39-52.
1990Guariguata, M.R, and Larsen, M.C., 1990, Preliminary map showing landslides in El Yunque quadrangle, Puerto Rico: U.S. Geological Survey Open-file Report 89-257, scale 1:20,000, 1 sheet.
2004Kinner, D.A., and Stallard, R.F., 2004, Identifying storm-flow pathways in a rainforest catchment using hydrometric and geochemical evidence: Hydrological Processes, v. 18, p. 2851-2875.
1990Larsen, M. C., and Simon, A., 1990, Landslide processes in saprolitic soils of a tropical rain forest, Puerto Rico, in Larue, D.K., and Draper, G., eds., Transactions of the 12th Caribbean Geological Conference, St. Croix, U.S. Virgin Islands: Miami Geological Society, p. 217-222.
1990 Larsen, M. C., and Torres-Sánchez, A. J., 1990, Rainfall-soil moisture relations in landslide-prone areas of a tropical rain forest, Puerto Rico, in Krishna, J. H., Quinones-Aponte, Vicente, Gomez-Gomez, Fernando, and Morris, G. L., eds., Tropical Hydrology and Caribbean Water Resources: Proceedings of the International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress, p. 121-130.
1992Larsen, M. C., and Torres-Sánchez, A. J., 1992, Landslides triggered by Hurricane Hugo in eastern Puerto Rico, September 1989: Caribbean Journal of Science, vol. 28, no. 3-4, p. 113-125.
1993Larsen, M.C., and Simon, Andrew, 1993, Rainfall-threshold conditions for landslides in a humid-tropical system, Puerto Rico: Geografiska Annaler, v. 75A (1-2), p. 13-23.
1993 Larsen, M.C., Collar, P.D., and Stallard, R.F., 1993, Research plan for the investigation of water, energy, and biogeochemical budgets in the Luquillo mountains, Puerto Rico: U.S. Geological Survey Open-file Report 92-150, 19 p.
1995Larsen, M.C., 1995, Use of seismic refraction techniques for investigating recent landslides in a tropical rain forest in Puerto Rico in Miller, R.L., Escalante, J.A., Reinemund, J.A., and Bergin, M.J., eds., Energy and Mineral Potential of the Central American-Caribbean Regions, Springer-Verlag, Berlin, p. 411-414.
1996Larsen, M.C., Torres Sánchez, A.J., 1996, Climatologic, geographic, and geologic factors influencing the distribution and occurrence of landslides in the Blanco, Cibuco, and Coamo river basins, Puerto Rico: U.S. Geological Survey Water Resources Investigations Report 95-4029, 56 p.
1997Larsen, M.C. and Parks, J.E., 1997, How wide is a road? The association of roads and mass-wasting disturbance in a forested montane environment: Earth Surface Processes and Landforms, vol. 22, no. 9, p. 835-848.
1998Larsen, M.C., and Torres Sánchez, A.J., 1998, The frequency and distribution of recent landslides in three montane tropical regions of Puerto Rico: Geomorphology, v. 24, no. 4, p. 309-331.
1998Larsen, M.C. and Concepción, I.M., 1998, Water budgets of forested and agriculturally-developed watersheds in Puerto Rico : Proceedings, Tropical Hydrology and Caribbean Water Resources, R.I. Segarra-García, ed., American Water Resources Association, San Juan, Puerto Rico, July 12-16, 1998, p. 199-204.
1999Larsen, M.C., Torres-Sánchez, A.J., and Concepción, I.M., 1999, Slopewash, surface runoff, and fine-litter transport in forest and landslide scars in humid-tropical steeplands, Luquillo Experimental Forest, Puerto Rico: Earth Surface Processes and Landforms, vol. 24, p. 481-502.
2000Larsen, M.C. and Stallard, R.F., 2000, Water, Energy,and Biogeochemical Budgets Luquillo Mountains, Puerto Rico: U.S. Geological Survey Fact Sheet, FS 163-99, 4 p.
2000Larsen, M.C., 2000, Analysis of 20th century rainfall and streamflow to characterize drought and water resources in Puerto Rico: Physical Geography, v. 21, p. 494-521.
2001Larsen, M.C. and Santiago-Román, Abigail, 2001, Mass wasting and sediment storage in a small montane watershed: an extreme case of anthropogenic disturbance in the humid tropics, in Dorava, J. M., Palcsak, B.B., Fitzpatrick, F. and Montgomery, D., eds., Geomorphic Processes and Riverine Habitat: American Geophysical Union, Water Science & Application Series Volume 4, p. 119-138.
2001Larsen, M.C., 2001, Evaluation of temporal and spatial factors that control the susceptibility to rainfall-triggered landslides, in Gruntfest, E., and Handmer, J., eds., Coping with Flash floods: Kluwer Academic Publishers, p. 277-288.
2001Larsen, M.C., Vásquez-Conde, M.T., and Clark, R.A., 2001, Flash-flood related hazards: landslides, with examples from the December, 1999 disaster in Venezuela, in E. Gruntfest and J. Handmer, eds., Coping with Flash floods: Kluwer Academic Publishers, p. 259-275.
2009Larsen, M.C. and Webb, R.M.T. (2009) Potential effects of runoff, fluvial sediment and nutrient discharges on the coral reefs of Puerto Rico: Journal of Coastal Research, 25, 189-208.
2012Minyard M.L., Bruns M.A., Liermann L.J., Buss H.L., and Brantley S.L., 2012. Bacterial Associations with Weathering Minerals at the Regolith-Bedrock Interface, Luquillo Experimental Forest, Puerto Rico. Geomicrobiology Journal, vol 28, issue 9, p. 792-803.
2010Minyard M.L., Bruns M.A., Martinez C.E., Liermann L.J., Buss H.L., and Brantley S.L. (2010) Occurrence of halloysite nanotubes and bacteria in a quartz diorite weathering front, Rio Icacos Watershed, Puerto Rico. SSSAJ. In Press.
1998Murphy, S.F., Brantley, S.L., Blum, A.E., White, A.F, Dong, Hailiang, 1998, Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico: II. Rate and mechanism of biotite weathering: Geochimica et Cosmochimica Acta, v. 62, no. 2, p. 227-243.
1997Myster, R.W., Thomlinson, J.R., and Larsen, M.C., 1997, Predicting landslide vegetation in patches on landscape gradients in Puerto Rico: Landscape Ecology, v. 12 p. 299-307.
2009Murphy, S.F. and Stallard, R.F., 2009, Primary factors affecting water quality and quantity in four watersheds in Eastern Puerto Rico, in Webb, R.M.T., and Semmens, D.J., eds, Proceedings of the Third Interagency Conference on Research in the Watersheds: Planning for an Uncertain Future: Monitoring, Integration, and Adaptation: U.S. Geological Survey Scientific Investigations Report 2009-5049. Estes Park, Colorado, September 9-11, 2008, p. 251-256.
2006Peters, N E; Shanley, J B; Aulenbach, B T; Webb, R M; Campbell, D H; Hunt, R; Larsen, M C; Stallard, R F; Troester, J; Walker, J F. (2006) Water and solute mass balance of five small, relatively undisturbed watersheds in the U.S., Science of The Total Environment, 358, 221-242.
2001Santiago M., and Larsen, M.C., 2001, Earthquake-induced landslide susceptibility in the San Juan Metropolitan Area, Puerto Rico: U.S. Geological Survey Open-file Report 01-39, 1 CD.
1991Scatena, F. N., and Larsen, M. C., 1991, Physical aspects of Hurricane Hugo in Puerto Rico: Biotropica, v. 23, no. 4A, p. 317-323.
2009Scholl, M.A., Shanley, J.B., Zegarra, J.P., and Coplen, T.B., 2009, The stable isotope amount effect: New insights from NEXRAD echo tops: Water Resources Research, v. 45, W12407, doi. 10.1029/2008WR007515.
1999Schulz, M.S. and White, A.F., 1999, Chemical Weathering in a Tropical Watershed, Luquillo Mountains, Puerto Rico: III. Quartz Dissolution Rates. Geochimica et Cosmochimica Acta, vol. 63, p. 337-350.
2008Shanley, J.B., M.A. Mast, D.H. Campbell, G.R. Aiken, D.P. Krabbenhoft, R.J. Hunt, J.F. Walker, P.F. Schuster, A. Chalmers, B.T. Aulenbach, N.E. Peters, M. Marvin-DiPasquale, D.W. Clow, and M.M. Shafer (2008). Comparison of total mercury and methylmercury cycling at five sites using the small watershed approach. Environmental Pollution 154, 143-154.
1990Simon, A., Larsen, M. C., and Hupp, C. R., 1990, The role of soil processes in determining mechanisms of slope failure and hillslope development in a humid-tropical forest: eastern Puerto Rico, in Kneuper, P.L.K., and McFadden, L. D., eds., Soils and Landscape evolution: Geomorphology, v. 3, p. 263-286.
1995Stallard, R.F., 1995, Relating chemical and physical erosion, in Chemical Weathering Rates of Silicate Minerals: Washington, D.C., Mineralogical Society of America, Reviews in Mineralogy 31, p. 543-564, 583 pages.
1995Stallard, R.F., 1995, Tectonic, environmental, and human aspects of weathering and erosion: A global review using a steady-state perspective: Annual Review of Earth and Planetary Sciences, v. 12, p. 11-39.
1998Stallard, R. F., 1998, Terrestrial sedimentation and the carbon cycle: Coupling weathering and erosion to carbon burial: Global Biogeochemical Cycles, v. 12, no. 2, p. 231-252.
2000Stallard, R.F. 2000, Tectonic processes and erosion, in Jacobson, M.C., Charleson, R.J., Rodhe, H., and Orians, G.H., editors, Earth System Science: From Biogeochemical Cycles to Global Change: San Diego, California, Academic Press. p. 195-229.
2001Stallard, R.F.: 2001, Possible Environmental Factors Underlying Amphibian Decline in Eastern Puerto Rico--Analysis of U.S. Government Data Archives: Conservation Biology, v. 15, no. 4, p. 943-953.
1998Stonestrom, D.A., White, A.F., and Akstin, K.C., 1998, Determining rates of chemical weathering in soils--Solute transport versus profile evolution: Journal of Hydrology, v. 209, p. 331-345.
2004Svenning, J.-C., Kinner, D.A., Stallard, R.F., Engelbrecht, B., and Wright, S.J., 2004, Determinism in plant community structure across a tropical forest landscape: Ecology, v. 85, p. 2526-2538.
2003Turner, B.F., Stallard, R.F., and Brantley, S.L., 2003, Investigation of quartz diorite weathering in the Rio Icacos Basin, Luquillo Experimental Forest, Puerto Rico: Chemical Geology, v. 202, p. 313-341.
2005Warne, A.G., Webb, R.M.T. and Larsen, M.C. (2005) Water, sediment, and nutrient discharge characteristics of rivers in Puerto Rico, and their potential influence on coral reefs. U.S. Geological Survey Scientific Investigations Report 2005-5206. 58 p.
1997Webb, Richard M.T., and Soler-López, Luis R. (1997) Sedimentation History of Lago Loíza, Puerto Rico, 1953-1994: U.S. Geological Resources Water-Resources Investigations Report 97-4108, 18 p.
1994White, A.F., 1994, Chemical weathering rates of silicate minerals in soils in White, A.F., and Brantley, S.L., Chemical Weathering Rates of Silicate Minerals, Reviews in Mineralogy, v. 31, p. 407-461.
1995White, A.F., and Blum, A.E., 1995, Effects of climate on chemical weathering in watersheds: Geochimica et Cosmoschimica Acta, v. 59, no. 9, p. 1729-1747.
1995White, A.F., and Blum, A.E., 1995, Climatic effects on chemical weathering in watersheds-- application of mass balance approaches in Trudgill, S.T., ed., Solute Modelling in Catchment Systems, John Wiley and Sons, Ltd., London, p. 102-131.
1998White, A.F, Blum, A.E., Schulz, M.S., Vivit, D.V., Stonestrom, D.A., Larsen, Matthew, Murphy, S.F., and Eberl, D., 1998, Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico: I. Long-term versus short-term weathering fluxes: Geochimica et Cosmochimica Acta, v. 62, no. 2, p. 209-226.
1998White, A.F., and Stonestrom, D.A., 1998, Comparisons of short-term and long-term chemical weathering rates in granitoid regoliths, in Arehart, G.B., and Hulston, J.R., eds., Proceedings of the 9th International Symposium on Water-Rock Interaction, WRI-9, Taupo, New Zealand, March 30-April 3, 1998, p. 399-402.
1999White, A.F., Blum, A.E., Bullen, T.D., Vivit, D.V., Schulz, Marjorie, and Fitzpatrick, John, 1999, The effect of temperature on experimental and natural chemical weathering rates of granitoid rocks: Geochimica et Cosmochimica Acta, vol. 63, p. 3277-3291.
1994Zack, Allen, and Larsen, M.C., 1994, Island hydrology: Puerto Rico and the U.S. Virgin Islands: National Geographic Research & Exploration: Water Issues, p. 126-134.
2012Buss, H. L. and A. F. White (2012). Weathering processes in the Icacos and Mameyes watersheds in eastern Puerto Rico-Chapter I. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 249-262.
2012Gould, W. A., et al. (2012). Land use, population dynamics, and land-cover change in eastern Puerto Rico-Chapter B. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 25-42.
2012Larsen, M. C. (2012). Landslides and sediment budgets in four watersheds in eastern Puerto Rico-Chapter F. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 153-178.
2012Larsen, M. C., et al. (2012). Effects of earthworms on slopewash, surface runoff, and fine-litter transport on a humid-tropical forested hillslope in eastern Puerto Rico-Chapter G. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 179-197.
2010Murphy, S. F. and R. F. Stallard (2010). Assessing global change effects in eastern Puerto Rico: Observations and complicating factors at the small watershed scale, Reston, Virginia, U.S. Geological Survey.
2012Murphy, S. F. and R. F. Stallard (2012). Appendix 2-Methods used to analyze water quality of four watersheds in eastern Puerto Rico. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 289-292.
2012Murphy, S. F. and R. F. Stallard (2012). Appendix 2-Methods used to analyze water quality of four watersheds in eastern Puerto Rico. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 289-292.
2012Murphy, S. F. and R. F. Stallard (2012). Hydrology and climate of four watersheds in eastern Puerto Rico-Chapter C. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 43-84.
2012Murphy, S. F. and R. F. Stallard (2012). Water Quality and Landscape Processes of Four Watersheds in Eastern Puerto Rico, U.S. Geological Survey: 292.
2012Murphy, S. F. and R. F. Stallard (2012). Water quality and landscape processes of four watersheds in eastern Puerto Rico. Reston, VA, U. S. Geological Survey.
2012Murphy, S. F., et al. (2012). Physiography, geology, and land cover of four watersheds in eastern Puerto Rico-Chapter A. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 1-23.
2011Ogden, F. L., et al. (2011). A Panama Canal Watershed Experiment: The Agua Salud Project, Panama, Republic of Panama, Panama Canal Authority and UNESCO.
2011Ogden, F. L., et al. (2011). A Panama Canal Watershed Experiment: The Agua Salud Project, Panama, Republic of Panama, Panama Canal Authority and UNESCO.
2014Scholl, M. A. and S. F. Murphy (2014). Precipitation isotopes link regional climate patterns to water supply in a tropical mountain forest, eastern Puerto Rico. Water Resources Research 50(5): 4305-4322.
2014Scholl, M. A., et al. (2014). Stable isotope (delta 18O and delta 2H) data for precipitation, stream water and groundwater in Puerto Rico. U.S. Geological Survey Open-File Report 2014-1101, U.S. Geological Survey: 29 p.
2011Shanley, J. B., et al. (2011). "Long-term patterns and short-term dynamics of stream solutes and suspended sediment in a rapidly weathering tropical watershed." Water Resources Research 47(7): W07515.
2011Stallard, R. F. (2011). "Weathering, landscape, and carbon in four paired research watersheds in eastern Puerto Rico." Applied Geochemistry 26(0): S370-S372.
2012Stallard, R. F. (2012). Appendix 1-Data processing and computation to characterize hydrology and compare water quality of four watersheds in Puerto Rico. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 263-287.
2012Stallard, R. F. (2012). Atmospheric inputs to watersheds of the Luquillo Mountains in eastern Puerto Rico-Chapter D. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 85-112.
2012Stallard, R. F. (2012). Weathering, landscape equilibrium, and carbon in four watersheds in eastern Puerto Rico-Chapter H. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 199-248.
2012Stallard, R. F. and S. F. Murphy (2012). Water quality and mass transport in four watersheds in eastern Puerto Rico-Chapter E. Water quality and landscape processes of four watersheds in eastern Puerto Rico. S. F. Murphy and R. F. Stallard. Reston, VA, U. S. Geological Survey: 113-152.
2014Stallard, R. F. and S. F. Murphy (2014). A unified assessment of hydrological and biogeochemical responses in research watersheds in eastern Puerto Rico using runoff-concentration relations. Aquatic Geochemistry 20: 115-139.

 

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