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Precipitation Characteristics and Land Cover Control Wet Season Runoff Source and Rainfall Partitioning in Three Humid Tropical Catchments in Central PanamaBirch, Andrew L.Stallard, Robert F.Barnard, Holly R.DOI: info:10.1029/2020WR028058v. 57No. 2
Birch, Andrew L., Stallard, Robert F., and Barnard, Holly R. 2021. "Precipitation Characteristics and Land Cover Control Wet Season Runoff Source and Rainfall Partitioning in Three Humid Tropical Catchments in Central Panama." Water Resources Research 57 (2):https://doi.org/10.1029/2020WR028058
ID: 159176
Type: article
Authors: Birch, Andrew L.; Stallard, Robert F.; Barnard, Holly R.
Abstract: Mechanisms of runoff generation in the humid tropics are poorly understood, particularly in the context of land-use/land cover change. This study analyzed the results of 124 storm hydrographs from three humid tropical catchments of markedly different vegetation cover and land-use history in central Panama during the 2017 wet season: actively grazed pasture, young secondary succession, and near-mature forest. We used electrical conductivity to separate baseflow (old water) from storm-event water (new-water). In all three land covers, new-water dominated storm runoff generation in 44% of the sampled storm events, indicating the dominance of fast shallow flow paths in the landscape. Activation of these flow paths was found to depend on a combination of maximum rainfall intensity and total storm rainfall, which, in turn, relates to markedly contrasting hydrograph separation results among land covers. Relationships between these rainfall characteristics and storm runoff generation were nonlinear, producing a threshold response with the exceedance of specific rainfall volumes and/or intensities. The pastoral catchment delivered order of magnitude more new-water during storm events than the two forested catchments. Although new-water contributed minimally (<10%) to total wet season runoff in the forested catchments, 43% of runoff generation in the pasture came from five large rainfall events where a threshold response produced substantial increases in total runoff and new-runoff efficiency. Based on our results, we propose a conceptual model of hydrologic flow paths in humid tropical systems that can explain previously observed disparities in seasonal storage and runoff with respect to land use/land cover.
The influence of land cover and storm magnitude on hydrologic flowpath activation and runoff generation in steep tropical catchments of central PanamaBirch, Andrew L.Stallard, Robert F.Bush, Sidney A.Barnard, Holly R.DOI: info:10.1016/j.jhydrol.2021.126138v. 596
Birch, Andrew L., Stallard, Robert F., Bush, Sidney A., and Barnard, Holly R. 2021. "The influence of land cover and storm magnitude on hydrologic flowpath activation and runoff generation in steep tropical catchments of central Panama." Journal of Hydrology 596:https://doi.org/10.1016/j.jhydrol.2021.126138
ID: 159701
Type: article
Authors: Birch, Andrew L.; Stallard, Robert F.; Bush, Sidney A.; Barnard, Holly R.
Abstract: Despite abundant research documenting that land use/land cover (LULC) have substantial impacts on the hydrology of humid tropical systems, field-based evidence for the physical mechanisms behind these impacts are still lacking. In particular, our understanding of the hydrologic flowpaths that generate runoff in these systems, and how they vary with respect to LULC is insufficient to inform both physically-based hydrologic modeling and land-use decision-making. In this study, we use end-member mixing analysis (EMMA) of stream chemistry, and hydrometric characterizations of hillslope soil moisture to identify hydrologic flowpaths in humid tropical steepland catchments of varying LULC: mature tropical forest, young secondary tropical forest, cattle pasture. EMMA was applied to data from 14 storm events (six at the mature forest, five at the young secondary forest, and three at the cattle pasture) that were intensively sampled during the 2017 wet season representing a wide range of rainfall magnitudes and intensities. Additionally, volumetric-soil-moisture responses at multiple depths were characterized during and after 74 storm events occurring from 2015 to 2017. EMMA results indicated that lateral preferential flow within the top 30 cm of the soil profile was a dominant source of runoff generation at the two forested catchments, with the contribution of this flow path increasing with rainfall magnitude and intensity. This was corroborated by volumetric-soil-moisture data, that showed that a perched zone of saturation developed at 30 cm at the time of peak storm runoff during the largest events and lasted for the remaining duration of the event. EMMA indicated that runoff was a combination of infiltration-excess overland flow and lateral subsurface flow in the actively grazed pastoral catchment. There, overland flow contributed 62 % of runoff during the highest runoff rate sampled (35.3 mm/hr) and this contribution increased substantially with storm magnitude. This flowpath identification was also supported by volumetric-soil-moisture data at the pasture, with peak saturation at all depths during the largest storm events occurring up to 30 min after peak runoff. These results provide a mechanistic explanation for previously observed hydrologic differences among tropical LULCs. Additionally, the wide range of hydrologic conditions during these storm events provide a basis for understanding how future changes to this, and similar humid tropical regions will impact hydrological processes and water availability.
Lutz Creek watershed, Barro Colorado Island, Republic of PanamaLarsen, Matthew C.Stallard, Robert F.Paton, StevenDOI: info:10.1002/hyp.14157v. 35No. 4
Larsen, Matthew C., Stallard, Robert F., and Paton, Steven. 2021. "Lutz Creek watershed, Barro Colorado Island, Republic of Panama." Hydrological Processes 35 (4):https://doi.org/10.1002/hyp.14157
Assessing ecological infrastructure investmentsAdamowicz, WiktorCalderon-Etter, LauraEntem, AliciaFenichel, Eli P.Hall, Jefferson S.Lloyd-Smith, PatrickOgden, Fred L.Regina, Jason A.Rad, Mani RouhiStallard, Robert F.DOI: info:10.1073/pnas.1802883116v. 116No. 125254–5261
Adamowicz, Wiktor, Calderon-Etter, Laura, Entem, Alicia, Fenichel, Eli P., Hall, Jefferson S., Lloyd-Smith, Patrick, Ogden, Fred L., Regina, Jason A., Rad, Mani Rouhi, and Stallard, Robert F. 2019. "Assessing ecological infrastructure investments." Proceedings of the National Academy of Sciences 116 (12):5254– 5261. https://doi.org/10.1073/pnas.1802883116
ID: 150713
Type: article
Authors: Adamowicz, Wiktor; Calderon-Etter, Laura; Entem, Alicia; Fenichel, Eli P.; Hall, Jefferson S.; Lloyd-Smith, Patrick; Ogden, Fred L.; Regina, Jason A.; Rad, Mani Rouhi; Stallard, Robert F.
Abstract: Conventional markets can underprovide ecosystem services. Deliberate creation of a market for ecosystem services e.g., a payments for ecosystem services (PES) scheme] can close the gap. The new ecosystem service market alters behaviors and quantities of ecosystem service provided and reveals prices for the ecosystems service: a market-clearing equilibrium. Assessing the potential for PES programs, which often act as ecological infrastructure investment mechanisms, requires forecasting the market-clearing equilibrium. Forecasting the equilibrium is complicated, especially at relevant social and ecological scales. It requires greater disciplinary integration than valuing ecosystem services or computing the marginal cost of making a land-use change to produce a service. We conduct an ex ante benefit–cost assessment and forecast market-clearing prices and quantities for ecological infrastructure investment contracts in the Panama Canal Watershed. The Panama Canal Authority could offer contracts to private farmers to change land use to increase dry-season water flow and reduce sedimentation. A feasible voluntary contracting system yields a small program of about 1,840 ha of land conversion in a 279,000-ha watershed and generates a 4.9 benefit–cost ratio. Physical and social constraints limit market supply and scalability. Service delays, caused by lags between the time payments must be made and the time services stemming from ecosystem change are realized, hinder program feasibility. Targeting opportunities raise the benefit–cost ratio but reduce the hectares likely to be converted. We compare and contrast our results with prior state-of-the-art assessments on this system.
Land use history and population dynamics of free-standing figs in a maturing forestAlbrecht, LarissaStallard, Robert F.Kalko, Elisabeth K. V.DOI: info:10.1371/journal.pone.0177060v. 12No. 51–18
Albrecht, Larissa, Stallard, Robert F., and Kalko, Elisabeth K. V. 2017. "Land use history and population dynamics of free-standing figs in a maturing forest." PloS One 12 (5):1– 18. https://doi.org/10.1371/journal.pone.0177060
ID: 143128
Type: article
Authors: Albrecht, Larissa; Stallard, Robert F.; Kalko, Elisabeth K. V.
Abstract: Figs (Ficus sp.) are often considered as keystone resources which strongly influence tropical forest ecosystems. We used long-term tree-census data to track the population dynamics of two abundant free-standing fig species, Ficus insipida and F. yoponensis, on Barro Colorado Island (BCI), a 15.6-km2 island in Lake Gatún, Panama. Vegetation cover on BCI consists of a mosaic of old growth (>400 years) and maturing (about 90-150 year old) secondary rainforest. Locations and conditions of fig trees have been mapped and monitored on BCI for more than 35 years (1973-2011), with a focus on the Lutz Catchment area (25 ha). The original distribution of the fig trees shortly after the construction of the Panama Canal was derived from an aerial photograph from 1927 and was compared with previous land use and forest status. The distribution of both fig species (~850 trees) is restricted to secondary forest. Of the original 119 trees observed in Lutz Catchment in 1973, >70% of F. insipida and >90% of F. yoponensis had died by 2011. Observations in other areas on BCI support the trend of declining free-standing figs. We interpret the decline of these figs on BCI as a natural process within a maturing tropical lowland forest. Senescence of the fig trees appears to have been accelerated by severe droughts such as the strong El Niño event in the year 1982/83. Because figs form such an important food resource for frugivores, this shift in resource availability is likely to have cascading effects on frugivore populations.
Formation of the Isthmus of PanamaO'Dea, AaronLessios, Harilaos A.Coates, Anthony G.Eytan, Ron I.Restrepo-Moreno, SergioCione, Alberto L.Collins, Laurel S.de Queiroz, AlanFarris, David W.Norris, Richard D.Stallard, Robert F.Woodburne, Michael O.Aguilera, OrangelAubry, Marie-PierreBerggren, William A.Budd, Ann F.Cozzuol, Mario A.Coppard, Simon E.Duque-Caro, HermanFinnegan, SethGasparini, German M.Grossman, Ethan L.Johnson, Kenneth G.Keigwin, Lloyd D.Knowlton, NancyLeigh, Egbert Giles, Jr.Leonard-Pingel, JillMarko, Peter B.Pyenson, Nicholas D.Rachello-Dolmen, PaolaSoibelzon, EstebanSoibelzon, LeopoldoTodd, Jonathan A.Vermeij, Geerat J.Jackson, Jeremy B. C.DOI: info:10.1126/sciadv.1600883v. 2No. 8
O'Dea, Aaron, Lessios, Harilaos A., Coates, Anthony G., Eytan, Ron I., Restrepo-Moreno, Sergio, Cione, Alberto L., Collins, Laurel S., de Queiroz, Alan, Farris, David W., Norris, Richard D., Stallard, Robert F., Woodburne, Michael O., Aguilera, Orangel, Aubry, Marie-Pierre, Berggren, William A., Budd, Ann F., Cozzuol, Mario A., Coppard, Simon E., Duque-Caro, Herman, Finnegan, Seth, Gasparini, German M., Grossman, Ethan L., Johnson, Kenneth G., Keigwin, Lloyd D., Knowlton, Nancy et al. 2016. "Formation of the Isthmus of Panama." Science Advances 2 (8):https://doi.org/10.1126/sciadv.1600883
ID: 140180
Type: article
Authors: O'Dea, Aaron; Lessios, Harilaos A.; Coates, Anthony G.; Eytan, Ron I.; Restrepo-Moreno, Sergio; Cione, Alberto L.; Collins, Laurel S.; de Queiroz, Alan; Farris, David W.; Norris, Richard D.; Stallard, Robert F.; Woodburne, Michael O.; Aguilera, Orangel; Aubry, Marie-Pierre; Berggren, William A.; Budd, Ann F.; Cozzuol, Mario A.; Coppard, Simon E.; Duque-Caro, Herman; Finnegan, Seth; Gasparini, German M.; Grossman, Ethan L.; Johnson, Kenneth G.; Keigwin, Lloyd D.; Knowlton, Nancy; Leigh, Egbert Giles, Jr.; Leonard-Pingel, Jill; Marko, Peter B.; Pyenson, Nicholas D.; Rachello-Dolmen, Paola; Soibelzon, Esteban; Soibelzon, Leopoldo; Todd, Jonathan A.; Vermeij, Geerat J.; Jackson, Jeremy B. C.
Que tan Viejo es el Istmo de PanamaCoates, Anthony G.Stallard, Robert F.Rodriguez Mejia, Felix A.O'Dea, AaronSENACYT/STRI17–28
Coates, Anthony G. and Stallard, Robert F. 2015. "Que tan Viejo es el Istmo de Panama." in Historia natural del Istmo de Panama, edited by Rodriguez Mejia, Felix A. and O'Dea, Aaron., 17– 28. SENACYT/STRI.
Implications of climate and land use changeHall, Jefferson S.Murgueitio, EnriqueCalle, ZoraidaRaudsepp-Hearne, CiaraStallard, Robert F.Balvanera, PatriciaHall, Jefferson S.Virn, VanessaYanguas-Fernandez, EstrellaSmithsonian Tropical Research Institute58–66
Hall, Jefferson S., Murgueitio, Enrique, Calle, Zoraida, Raudsepp-Hearne, Ciara, Stallard, Robert F., and Balvanera, Patricia. 2015. "Implications of climate and land use change." in Managing watersheds for ecosystem services in the steepland neotropics, edited by Hall, Jefferson S., Virn, Vanessa, and Yanguas-Fernandez, Estrella., 58– 66. Smithsonian Tropical Research Institute.
ID: 146651
Type: chapter
Authors: Hall, Jefferson S.; Murgueitio, Enrique; Calle, Zoraida; Raudsepp-Hearne, Ciara; Stallard, Robert F.; Balvanera, Patricia
Implicacioines del cambio climatico y del uso del sueloHall, Jefferson S.Murgueitio, EnriqueCalle, ZoraidaRaudsepp-Hearne, CiaraStallard, Robert F.Balvanera, PatriciaHall, Jefferson S.Kirn, VanessaYanguas-Fernandez, EstrellaInstituto Smithsonian de Investigaciones Tropicales65–74
Hall, Jefferson S., Murgueitio, Enrique, Calle, Zoraida, Raudsepp-Hearne, Ciara, Stallard, Robert F., and Balvanera, Patricia. 2015. "Implicacioines del cambio climatico y del uso del suelo." in La gestion de las cuencas hidrograficas para asegurar los servicios ecosistemicos en las laderas del Neotropico, edited by Hall, Jefferson S., Kirn, Vanessa, and Yanguas-Fernandez, Estrella., 65– 74. Instituto Smithsonian de Investigaciones Tropicales.
ID: 146638
Type: chapter
Authors: Hall, Jefferson S.; Murgueitio, Enrique; Calle, Zoraida; Raudsepp-Hearne, Ciara; Stallard, Robert F.; Balvanera, Patricia
Introduction to Watershed Ecosystem ServicesHall, Jefferson S.Stallard, Robert F.Kirn, VanessaHall, Jefferson S.Virn, VanessaYanguas-Fernandez, EstrellaSmithsonian Tropical Research Institute16–19
Hall, Jefferson S., Stallard, Robert F., and Kirn, Vanessa. 2015. "Introduction to Watershed Ecosystem Services." in Managing watersheds for ecosystem services in the steepland neotropics, edited by Hall, Jefferson S., Virn, Vanessa, and Yanguas-Fernandez, Estrella., 16– 19. Smithsonian Tropical Research Institute.
ID: 146647
Type: chapter
Authors: Hall, Jefferson S.; Stallard, Robert F.; Kirn, Vanessa
Introduccion a los servicios ecosistemicos de las cuencas hidrograficasHall, Jefferson S.Stallard, Robert F.Kirn, VanessaHall, Jefferson S.Kirn, VanessaYanguas-Fernandez, EstrellaInstituto Smithsonian de Investigaciones Tropicales18–21
Hall, Jefferson S., Stallard, Robert F., and Kirn, Vanessa. 2015. "Introduccion a los servicios ecosistemicos de las cuencas hidrograficas." in La gestion de las cuencas hidrograficas para asegurar los servicios ecosistemicos en las laderas del Neotropico, edited by Hall, Jefferson S., Kirn, Vanessa, and Yanguas-Fernandez, Estrella., 18– 21. Instituto Smithsonian de Investigaciones Tropicales.
ID: 146633
Type: chapter
Authors: Hall, Jefferson S.; Stallard, Robert F.; Kirn, Vanessa
Comprender el capital natural, parte A: Contexto geofisicoStallard, RobertHall, Jefferson S.Kirn, VanessaYanguas-Fernandez, EstrellaInstituto Smithsonian de Investigaciones Tropicales24–38
Stallard, Robert. 2015. "Comprender el capital natural, parte A: Contexto geofisico." in La gestion de las cuencas hidrograficas para asegurar los servicios ecosistemicos en las laderas del Neotropico, edited by Hall, Jefferson S., Kirn, Vanessa, and Yanguas-Fernandez, Estrella., 24– 38. Instituto Smithsonian de Investigaciones Tropicales.
ID: 146634
Type: chapter
Authors: Stallard, Robert
Understanding Natural Capital, part A: Geophysical contextStallard, Robert F.Hall, Jefferson S.Virn, VanessaYanguas-Fernandez, EstrellaSmithsonian Tropical Research Institute20–35
Stallard, Robert F. 2015. "Understanding Natural Capital, part A: Geophysical context." in Managing watersheds for ecosystem services in the steepland neotropics, edited by Hall, Jefferson S., Virn, Vanessa, and Yanguas-Fernandez, Estrella., 20– 35. Smithsonian Tropical Research Institute.
ID: 146648
Type: chapter
Authors: Stallard, Robert F.
A Unified Assessment of Hydrologic and Biogeochemical Responses in Research Watersheds in Eastern Puerto Rico Using Runoff–Concentration RelationsStallard, Robert F.Murphy, Sheila F.DOI: info:10.1007/s10498-013-9216-5v. 20No. 2/3115–139
Stallard, Robert F. and Murphy, Sheila F. 2014. "A Unified Assessment of Hydrologic and Biogeochemical Responses in Research Watersheds in Eastern Puerto Rico Using Runoff–Concentration Relations." Aquatic Geochemistry 20 (2/3):115– 139. https://doi.org/10.1007/s10498-013-9216-5
ID: 118086
Type: article
Authors: Stallard, Robert F.; Murphy, Sheila F.
How old is the Isthmus of Panama?Coates, Anthony G.Stallard, Robert F.DOI: info:10.5343/bms.2012.1076v. 89No. 4801–813
Coates, Anthony G. and Stallard, Robert F. 2013. "How old is the Isthmus of Panama?." Bulletin of Marine Science 89 (4):801– 813. https://doi.org/10.5343/bms.2012.1076
Effect of land cover and use on dry season river runoff, runoff efficiency and peak storm runoff in the seasonal tropics of central PanamaOgden, Fred L.Crouch, Trey D.Stallard, Robert F.Hall, Jefferson S.DOI: info:10.1002/2013WR013956v. 49No. 128443–8462
Ogden, Fred L., Crouch, Trey D., Stallard, Robert F., and Hall, Jefferson S. 2013. "Effect of land cover and use on dry season river runoff, runoff efficiency and peak storm runoff in the seasonal tropics of central Panama." Water Resources Research 49 (12):8443– 8462. https://doi.org/10.1002/2013WR013956
ID: 118092
Type: article
Authors: Ogden, Fred L.; Crouch, Trey D.; Stallard, Robert F.; Hall, Jefferson S.
Land use effects on ecosystem service provisioning in tropical watersheds, still and important unsolved problemOgden, FredStallard, Robert F.DOI: info:10.1073/pnas.1314747111v. 110No. 52E5037
Ogden, Fred and Stallard, Robert F. 2013. "Land use effects on ecosystem service provisioning in tropical watersheds, still and important unsolved problem." Proceedings of the National Academy of Sciences of the United States of America 110 (52):E5037. https://doi.org/10.1073/pnas.1314747111
ID: 127675
Type: article
Authors: Ogden, Fred; Stallard, Robert F.
Water quality and landscape processes of four watersheds in eatern Puerto RicoMurphy, Sheila F.Stallard, Robert F.U.S. Geological Survey292
Murphy, Sheila F. and Stallard, Robert F. , eds. 2012. Water quality and landscape processes of four watersheds in eatern Puerto Rico. U.S. Geological Survey.
ID: 114847
Type: book
Hydrology and climate for four watersheds in eastern Puerto RicoMurphy, Sheila F.Stallard, Robert F.Murphy, Sheila F.Stallard, Robert F.U.S. Geological Survey43–84
Murphy, Sheila F. and Stallard, Robert F. 2012. "Hydrology and climate for four watersheds in eastern Puerto Rico." in Water quality and landscape processes of four watersheds in eastern Puerto Rico, edited by Murphy, Sheila F. and Stallard, Robert F., 43– 84. U.S. Geological Survey.
ID: 114849
Type: chapter
Authors: Murphy, Sheila F.; Stallard, Robert F.
Physiography, geology, and land cover of four watersheds in eastern Puerto RicoMurphy, Sheila F.Stallard, Robert F.Larsen, Matthew C.Gould, William A.Murphy, Sheila F.Stallard, Robert F.U.S. Geological Survey1–24
Murphy, Sheila F., Stallard, Robert F., Larsen, Matthew C., and Gould, William A. 2012. "Physiography, geology, and land cover of four watersheds in eastern Puerto Rico." in Water quality and landscape processes of four watersheds in eastern Puerto Rico, edited by Murphy, Sheila F. and Stallard, Robert F., 1– 24. U.S. Geological Survey.
ID: 114848
Type: chapter
Authors: Murphy, Sheila F.; Stallard, Robert F.; Larsen, Matthew C.; Gould, William A.