Effect of agrochemicals on macroinvertebrate assemblages in Pampasic streams, Buenos Aires, Argentina

SOLIS M; MUGNI H; FANELLI S.L.; BONETTO C

Environmental Earth Sciences

Springer Berlin Heidelberg

Lugar: Berlín; Año: 2017 vol. 76 p. 1 - 13

1866-6280

Agricultural practices have been intensified inrecent decades in Argentina. The Pampa plain is the mainagricultural region of the country. The effect of increasedapplication of agrochemicals on the invertebrate fauna ofthe Pampasic streams remains unreported. In the presentstudy, we compared the abundance and composition ofinvertebrate assemblages in seven Pampasic streams withcontrasting soil use in their basins. Two streams runthrough intensively cropped plots, two drain basins withlivestock fields, while the other three are located within abiosphere Reserve. Higher nutrient and insecticide concentrationswere measured in the streams draining croppedbasins, related with pesticide applications and crop fertilization.The invertebrate assemblage composition of thecropped streams differed significantly from the others andbetween the two. Present evidence suggests that the impactof agrochemicals results in a change in composition withdecreased abundance or absence of sensitive species suchas Hyalellidae, Caenidae, Baetidae and Curculionidae andincreased abundance of more tolerant taxa: Ostracoda,Glossiphoniidae (Hirudinea), Ancylidae (Gundlanchia),Ampullariidae (Pomacea canaliculata), Sphaeriidae andDugesiidae. Available information suggests that macrophytecover and composition also influence the invertebrateassemblages of the Pampasic streams.