Horticulture affects macroinvertebrate assemblages in adjacent streams (Buenos Aires, Argentina)

ARIAS, MARINA; SCALISE, ANA; SOLIS, MARINA; PARACAMPO, ARIEL; INDACO, MERCEDES; FANELLI, SILVIA; MUGNI, HERNÁN; BONETTO, CARLOS

KNOWLEDGE AND MANAGEMENT OF AQUATIC ECOSYSTEMS

EDP SCIENCES S A

Lugar: Paris; Año: 2020

1961-9502

Abstract ? The agrochemicals used on crops can reach watercourses, affecting water quality and biologiccommunities. The aim of this research was to study the effects of horticulture on the water quality andinvertebrate assemblages of adjacent streams in Buenos Aires province, Argentina. Four streams draininghorticultural basins were compared with another four considered less disturbed: two of the latter located in aBiosphere Reserve and the other two in extensive livestock-raising basins. Pesticides were detected inthe horticulture-related streams, while nutrient concentrations were significantly higher than in the lessdisturbed streams. The macroinvertebrate assemblages differed: the less-disturbed streams exhibited asignificantly higher taxa richness and density. Hyalella sp. and Simocephalus vetulus were dominant,whereas Entomobryoidea, Dugessidae, and Glossiphoniidae were dominant in the horticultureassociated streams. Ephemeroptera (Caenis and Baetidae) were well represented in the less-disturbedstreams and rare or absent in the horticulture-adjacent streams. Multivariate analysis indicated that thehorticulture-impacted sites contained high nutrient concentrations and tolerant taxa, while the lessdisturbed sites corresponded to lower nutrient concentrations and sensitive taxa. We propose Hyalella sp.and S. vetulus as water-quality indicators in pampean streams and conclude that intensive agrochemicalapplications in horticulture increase nutrient and pesticide loads affecting the macroinvertebrateassemblages of adjacent streams.