Turnitin: Prosiding SCRRD 2018 - Aquatic Macroinvertebrates of the Lower Santa Cruz River

Abstract

In arid climates, increasing water use has resulted in the loss of surface water resources. For example, much of the Santa Cruz River in southern Arizona lost perennial flow in the mid-1900s due to extensive groundwater pumping. However, portions of the river have been artificially reborn through effluent discharge from wastewater treatment plants. This effluent discharge has created aquatic habitat, but it is not known how taxa have responded to the artificial flow regime and water quality dynamics. We collect monthly samples along the lower Santa Cruz River at six reaches near Tucson, AZ. This monthly collection includes benthic multihabitat and drift net sampling and has uncovered a surprisingly diverse community yielding >100 aquatic macroinvertebrate species within the effluent-dominated lower Santa Cruz River. Our sampling has also revealed the presence of microplastics (such as micro beads from personal care products) in this treated wastewater. As urban development continues, discharge of effluent into rivers and streams will become more common. Continued research is needed to determine the viability of treated wastewater to augment or replace natural flows and to incorporate ecosystem services into effluent management.