Controlling factors affecting the presence and distribution of Didymosphenia geminata in lakes and rivers of the Neuquén province, Argentina

BEAMUD, SARA GUADALUPE; LAFFITTE, LORENA; MUÑIZ SAAVEDRA, JULIETA; BAFFICO, GUSTAVO; LAURENZANO, BETINA; DIAZ, MÓNICA; PEDROZO, FERNANDO

ECOHYDROLOGY

JOHN WILEY & SONS INC

Lugar: New York; Año: 2019

1936-0584

The diatom Didymosphenia geminata (D. geminata) is an invasive periphytic speciesfrom the Northern Hemisphere. D. geminata occurrence and mat formation inPatagonia Argentina dates from 2010, spreading throughout Patagonia (provinces ofChubut, Neuquén, Río Negro, and Santa Cruz) by 2017. In 2012, the Surveillance andMonitoring Program was implemented by Neuquén government entities. Within thisprogramme, nine sampling campaigns have been conducted at 91 sites includingstreams, rivers, lakes, reservoirs, and a canal. Presence or absence of D. geminatacells, abundance of D. geminata and other algal species cells as well as environmentalvariables were determined in samples. Multivariate analysis and generalized linearmodels were used to determine environmental constraints on habitat suitability andrequirements for D. geminata. During 2012?2017, D. geminata cells were detected at33 out of 91 sites sampled. D. geminata was present in lower streams order, with lowvalues of total and dissolved nutrients, conductivity, alkalinity, ions and solutes, andhigh values of dissolved oxygen and habitat quality, for the ranges of environmentalvariables measured at sampling sites. D. geminata abundance was negatively relatedto stream order. Our results prove that D. geminata is expanding its ecological spectrum,showing a wider tolerance to environmental conditions particularly for phosphorusand nitrogen, some ions such as magnesium, and even temperature, and theyconfirm some authors´ hypothesis about the ecological behaviour of this invasivespecies. Range expansion and environmental preferences of D. geminata could modifythe state of susceptibility to invasion in numerous waterbodies.