Kutsadura urbanoaren eta ur-eskasiaren arteko elkarreragina erreken funtzionamenduan

Abstract

Hiri-guneetako kutsadura oso estres faktore garrantzitsua da ibaientzat. Ur-eskasiak sistema hauek kalte ditzake ere, diluzio-gaitasunean eta hortaz, kutsatzaileen kontzentrazioan eragina baitu. Gure helburua kutsadura urbanoaren eta ur-eskasiaren elkarreraginaren efektua aztertzea izan zen ibai ekosistemen funtzionamenduan. Prozesu desberdinen erantzuna neurtu genuen lehorte gradiente batean kokatuta zeuden 13 erreketan Ebroko arroan zehar; bertan, isurketetatik behera (inpaktuak) eta gora zeuden tramoak aztertuz (kontrolak). Prozesuek, ordea, modu desberdinean erantzun zuten, isurketen ezaugarrien eta erreken diluzio-gaitasunaren arabera.

Pollution of urban areas is an important stress factor for rivers. Water scarcity can also affect these systems, as it determines the dilution capacity and affects pollutants final concentration. We evaluated the interactive effects of pollution and water scarcity on river ecosystem functioning. We analysed the response of different processes into 13 streams arranged in a gradient of water scarcity in the Ebro River basin, where reaches downstream (impact) received sewage inputs, while those upstream were used as control. Results show diverging responses among the processes, which depends on the effluent characteristics and the dilution capacity of the receiving water body.