Tropical South American Diatom Database


This site contains a description of the Tropical South American Diatom Database. The database includes diatom (unicelular siliceous algae) data and associated environmental variables of waterbody sites (streams, wetlands and lakes; n=270 sites aprox.), covering an altitudinal gradient from 220 to 5,070 m a.s.l. between 8°N–30°S and 58–79°W.

Diatom samples comprise sediment surface, core tops, periphyton, and plankton, collected in the period 1977–2009 by different investigators for a variety of scientific objectives (e.g. biodiversity, paleoclimatic reconstructions, taxonomic descriptions).

Depending on the variable and waterbody, three categories of environmental data are available:

  • Physical context (e.g. location, depth of the lake, area of the catchment)
  • Water chemistry (e.g. pH, conductity, nutrients)
  • Geo-climatic context (e.g. elevation, climatic, landscape aquatic connectivity)

Diatom data consist in site-by-species relative abundance matrices in about 90% of the samples, while species data of the remaining 10% of the samples consisted of presence–absence counts.

The database is mostly available on Dryad repository (see 'publications' on the left-hand menu) while here the aim is to provide a georeferenced database to promote biodiversity, biogeographic and palaeoecological studies in tropical South America using diatoms as sentinel organisms.

The database is a collaborative network of multiple researchers. We acknowledge funding received from:

  • NSF Grants EAR-1338694, NSF-EAR1251678, NASA 15-BIODIV15-0013, and National Geographic #8672-09 grants to Sheri Fritz
  • NSF Grants BSR-8021539 and BSR-8202658 to Miriam Steinitz-Kannan
  • NWO-WOTRO grant WB 75368 to Maria I. Velez
  • National Geographic #9797-15 and NSF EAR 1541247 to Michael M. McGlue
  • FONDECYT and the Institue of Ecology and Biodiversity through ICMP05-002 and PFB-23 grants to Maria L. Carrevedo

Authors are also grateful to colleagues who submitted samples and unpublished diatom and environmental data for the construction of the database:

  • Pedro Tapia (Universidad Cayetano Heredia, Perú)
  • John Smol and Neal Michelutti (PEARL, Queen´s University, Canada)
  • Frank Mayle (University of Reading, UK)
  • William Gosling (Open University, UK)
  • Bryan Valencia and Mark Bush (Florida International University, USA)
  • Blas Valero-Garcés (Instituto Pirenaico de Ecología, CSIC, Spain)
  • (late) J.P. Bradbury


Send me a message if you have any inquiry and want to collaborate with the database!

Alternatively, email me and I´ll get in contact as soon as I can.