Spatial and temporal trends and flow dynamics of glyphosate and other pesticides within an agricultural watershed in Argentina

 

Autores
Pérez, Débora Jesabel; Okada, Elena; de Gerónimo, Eduardo; Menone, Mirta Lujan; Aparicio, Virginia Carolina; Costa, Jose Luis
Tipo de recurso
artículo
Estado
Versión publicada
Año de publicación
2017
País
Argentina
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio
CONICET Digital (CONICET)
Descripción
In the present study, we evaluated the spatial and temporal trends of current-use pesticides in surface water and sediments as well as their relationship with hydrological stream dynamics within the agricultural watershed of El Crespo stream (Buenos Aires Province, Argentina). We sampled 2 contrasting sites: site 1 (upstream), surrounded by agricultural lands, and site 2 (downstream), surrounded by natural grasslands. Most of the applied pesticides (glyphosate, 2,4-D, atrazine, tebuconazole, and imidacloprid) were detected at high frequencies in surface water samples at both sites. However, only glyphosate and aminomethylphosphonic acid (AMPA) were present at high concentrations and had a significant spatial–temporal trend. The highest concentrations were found during spring 2014 at site 1, in association with the intense rains that occurred in that season. The fact that glyphosate and AMPA concentrations were higher than the rest of the studied compounds is closely related to the land use within the watershed, as glyphosate was the most applied herbicide during the fallow period of glyphosate-resistant crops (soybean, maize). The pesticide mixture had a significant spatial–temporal trend, reaching the highest levels during storm flow events in spring 2014. The intensive rains in spring 2014 could be the main factor influencing stream hydrology and pesticide behavior at El Crespo watershed. The estimated annual pesticide losses were 3.11 g/ha at site 1 and 0.72 g/ha at site 2. This result indicates that an attenuation process could be decreasing pesticide loads during downstream transport from site 1 to site 2.
Idioma
inglés
OAI Identifier
oai:ri.conicet.gov.ar:11336/54101
Enlace del recurso
http://hdl.handle.net/11336/54101
Nivel de acceso
Acceso abierto
Materia
GLYPHOSATE
PESTICIDE LOSS
PESTICIDE MIXTURE
STREAM DISCHARGE
SURFACE WATER
Agricultura
Agricultura, Silvicultura y Pesca
CIENCIAS AGRÍCOLAS