Blackflies as indicators of ecological stress in two Alpine streams with different land use in the catchment

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Blackfìies as indicators ofecological stress in two Alpine

streams with different land use in the catchment

BRUNo MAToLINI, SoNre Euoruzzt & M. CRrsrrNA BRUNO lìcse.rrch and Innoviìtion Centrc {CRl), Sust.ìin!ble Agro,t:co\\'st.ms and

Iljoresourccs l)rparrment, vic Medjci l2l, -l I-llÌl2l -lrLnro, lr.ììyi b, uno.n ìolini@fllrr.h.il

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strcanrs in ldjacent rvatersheds rvere sarnpled nronthly tÌonr spring to autunlD irì 2010 a,ld 201 l.'lhc trvo streams shared similar en\.ironnìentùl conditions but one clrailase ba sin rvls largely used for €xtensive agriculture and the second rvas in nedr b nttrrJl iondi-tions. Physical-chemicirl paraùete$ (mean water velocity, water teIìlperature, dissolved (),, pH, turbidity ànd conductivity) were measured in both strearns during each sanrpling occìsion. The benthic co munity rvas sampled tvith the standàrd kick-net technique and all individuals rvere counted and identilìed to the Iowest possible taxonornical level. Ilesults indiciìte significative differerìces bctween the inlpàcted ilncl relerence strcams ill tcrnrs ofabundance, composition and seasonality ofthe benthic contnrunities. The blackly liuna resulted generally more abundant but less diverse in the ilnpiìcted streant. domi-nirted by more tolerant sDecics.