Cyanobacterial blooms in subtropical riverine and estuarine ecosystems of South America

Water quality impairment caused by toxic cyanobacterial blooms is a growing global concern adversely affecting the biodiversity and functioning of aquatic ecosystems, which can disrupt recreation and human health. Recent studies indicate that factors such as eutrophication, dam construction, and climate change are likely to increase the frequency and intensity of these blooms in aquatic ecosystems worldwide. This trend raises concerns in the subtropical South America (SA) region, where the pampas ecosystem has registered a sustained increase in the surface used by agroindustrial activities which leads to eutrophication of the Uruguay River (UR) and the Río de la Plata estuary (RdlP) ecosystems. The UR-RdlP system is crucial for recreational activities and serves as an essential water source. Historical monitoring data indicate that currently, toxic blooms are often documented in the UR and transported downstream to the RdlP (Kruk et al., 2017; Martínez de la Escalera et al., 2017). 
In ..., Study area
The Uruguay River (UR) is one of the largest rivers in South America (SA). Its basin spans from 28°S to 37°S, covering a vast area of ca. 365,000 km2 and a linear extension of 1,838 km, of which ~540 km is the border between Argentina and Uruguay. At 31°S, the Salto Grande (SG) dam was built in 1974 to produce electricity (length ~100 km, average depth 6.4 m) and frequently presents toxic cyanobacterial blooms. At 35°S on the Atlantic coast of SA, lies the Rio de la Plata estuary (RdlP), with an extension of 325 km and a mean depth of 10 meters, draining the second largest basin of SA (3,170,000 km2) formed by the Paraná River and the UR. Within this basin, agricultural and industrial activities thrive, with approximately 15 million people living along its margins.
Sampling and data collection
Water quality, cyanobacterial blooms, and risk indices
 
Cyanobacteria information was compiled from publicly accessible reports and through formal requests from the Uruguayan Governmen..., , # Data from: Cyanobacterial blooms in subtropical riverine and estuarine ecosystems of South America

Corresponding author: Carla Kruk ([[e-mail]](mailto:[e-mail]))

We present a comprehensive historical dataset spanning ca. 60 years of toxic cyanobacterial blooms abundance and risk indices, which were linked to in-situ water characteristics and merge to regional environmental variables. This dataset encompasses a wide geographic range of beaches across key South American water ecosystems.

The dataset is organized and stored in four files, two .xls with and two .csv files:
File 1: Metadata.xls
File 2: Variables.xls
File 3: CyaRiskData.csv
File 4: HistoricalCyaData.csv

The first two files provide comprehensive information regarding the sources referenced for generating this dataset, including compiled variables. The last two files contain the outcomes of the obtained values for each variable, prepared for analysis. One dataset focuses on indices associated with exposure t...