The Impact of Herbicides on Benthic Organisms in Flooded Ricefields in Southern Brazil

Immatures of Chironomidae (Insecta – Diptera) under the action of pesticides in irrigated rice field

“…Since the benthonic community depends on phytoplankton for food, it is expected that its recovery takes place in a period of more than 10 days. Similar effect for the action of Quinclorac was found by Baumart, Santos (2010), who reported that Quinclorac had the greatest impact on the benthonic community among the pesticides examined in their study. Moreover, Daam et al (2009) reported that the application of the herbicide Linuron on an experimental microcosm led to an alteration of the algal community, eliminating some the sensitive species, which were the more digestible to the zooplankton.…”

Effects of carbofuran and metsulfuron-methyl on the benthic macroinvertebrate community in flooded ricefields

“…As seen in other studies (Schulz & Liess, 1999;Suhling et al, 2000;Baumart and Santos, 2010), with the end of the crop cycle, some taxa recolonized the area, and other groups already present increased in abundance.…”

“…In rice crop areas, the concentration of dissolved oxygen (DO) tends to be low due to the height of the water, usually between 5 and 15 cm. Other studies in the same area reported DO concentrations from 0.6 to 2.2 mg.L -1 , 2.4 to 4.6 mg.L -1 and 2.5 to 11.90 mg.L -1 (Baumart and Santos, 2010). In this study, DO ranged between 1.7 and 2.12 mg.L -1 ; however, because this difference was recorded before the pesticide application, probably the oxygen levels were not associated with these treatments.…”

“…In this study, DO ranged between 1.7 and 2.12 mg.L -1 ; however, because this difference was recorded before the pesticide application, probably the oxygen levels were not associated with these treatments. The low DO availability may have, however, restricted the colonization of the area by certain taxa that could be present if the DO concentrations were close to saturation, such as reported by Baumart and Santos (2010), who reported a higher diversity of taxa, when only control treatments are compared.…”

Diversity and conservation status of Aegla spp. (Anomura, Aeglidae): an update

“…use of pesticides in agriculture or by urban sewage, silvicultural practices, construction of hydroelectric plants, among others (Pérez-Losada et al, 2002b;Bond-Buckup et al, 2008;Baumart and Santos, 2010;Santos et al, 2012). Th e presence of some species in restrict areas, as in headwaters, several of them with a few records of occurrence, highlights even more the level of threat to the group's conservation (Magris et al, 2010).…”