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60 A Cuba 400 10 3 B
Average concentration [mg/L] 40 Martinique 300 Chem. weath. rate [tons km -2 yr −1 ] 10 2 1
Dominica
Guadeloupe

200
20
10
100

0
Ca Cl K Mg Na NO 3 Si SO 4 HCO TDS 0 10 0
3
Analyte Cuba Dominica Martinique
Global

Guadeloupe
3 C Mississippi River 6 1961 D
1978
1995
TDN [mg/L] 2 Fertilizer use [tons km -2 yr -1 ] 4 2016

2
1

25 Cuban Rivers (2018), 0.76±0.37 mg/L 0
2012 2014 2016 2018 Cuba United
Year Republic States
Jamaica
Dominican
Figure 6. Cuban river water data in context. (A) Cuban waters contain greater dissolved concentrations for most elements or ions than other Caribbean
islands (Rad et al., 2013). (B) Chemical weathering rates (cations, anions, and Si) in rivers sampled in central Cuba, Dominica, Guadeloupe, and Martinique
(Rad et al., 2013) are high and similar (cf. global from Larsen et al. [2014]; n = 299). Note log scale. Median is middle line, the 25th and 75th percentiles are
the edges, and whiskers extend to include all samples within 1.5 times the range of the box. (C) Total dissolved nitrogen (TDN) for Mississippi River at Baton
Rouge (water.usgs.gov) compared to central Cuban rivers (this paper). (D) Cuban fertilizer use (P, K, N) normalized by arable land area is stable and less than
other nations. Data from https://data.worldbank.org/indicator/, Rawlins et al. (1998), and https://www.epa.gov/roe/.

IMPLICATIONS where suspended sediment, and bacteria from Beck, H.E., de Roo, A.D., and van Dijk, A.I.J.M., 2015,
Our data provide a comprehensive snap- agricultural activity, impact water quality and Global maps of streamflow characteristics based
on observations from several thousand catchments:
shot of the chemistry of water moving through clarity on coral reefs and beaches frequented Journal of Hydrometeorology, v. 16, no. 4, p. 1478–
rivers in central Cuba. From these data, we by tourists (Rawlins et al., 1998), a source of 1501, https://doi.org/ 10.1175/ JHM-D -14 -0155.1.
calculate high rates of rock weathering and income to Cuba (Duffy and Kline, 2018). Beck, H.E., Vergopolan, N., Pan, M., Levizzani, V.,
landscape-scale denudation and thus infer the van Dijk, A.I.J.M., Weedon, G.P., Brocca, L.,
presence of flow paths through fresh rock or ACKNOWLEDGMENTS Pappenberger, F., Huffman, G.J., and Wood, E.F.,
regolith supplying water to rivers we sam- Support for field and analytic work provided by 2017, Global-scale evaluation of 22 precipitation
datasets using gauge observations and hydro-
pled—perhaps in response to tectonic uplift. NSF EAR-1719249 and NSF EAR-1719240 to logical modeling: Hydrology and Earth System
Cuba’s transition toward sustainable agricul- Bierman and Schmidt. Cuban researchers supported Sciences, v. 21, p. 6201–6217, https://doi .org/
by the MICATIN and ISOAGRI projects. We thank
ture (and its reduced use of fertilizer per acre W. Amidon, P. Ryan, and J. Smith (Middlebury Col- 10.5194/hess-21-6201-2017.
of crop land) results in much lower river-water lege) for ICP-MS data and J. Brown UVM for photog- Betancourt, C., Suarez, R., and Jorge, F., 2012, In-
nutrient concentrations in central Cuban riv- raphy. Some field costs and DNA tests supported by fluence of natural and antropic processes on the
ers than in the Mississippi River—a model for Oberlin College. We thank T. Dunne, B. McDowell, water quality in four Cuban reservoirs: Limneti-
ca, v. 31, p. 193–204.
and students in University of Vermont Geology 351
other agricultural economies. Additional for feedback on earlier versions of the manuscript. Cosculluela, J.A., 1946, Prehistoric Cultures of
management strategies to reduce manure and Cuba: American Antiquity, v. 12, no. 1, p. 10–18,
sediment loads to rivers (such as fencing to REFERENCES CITED https://doi.org/10.2307/275809.
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rapidly improve central Cuban river water and Ramsubhag, A., 2010, Assessment of non- water and watershed infrastructure: Annual Meet-
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will have economic benefits, because rivers Bulletin, v. 60, no. 7, p. 1117–1121, https:// doi .org/ .org/asce_proceedings/appendix -b-evaluation
eventually discharge into the coastal zone 10.1016/j.marpolbul.2010.04.020. -cubas-water-watershed-infraestructure-student
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