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Environmental quality assessment in Central Andean rivers: using the Ecological Thresholds Concept, Environmental Quality Standards, and Biotic Indexes
  • Eduardo Oyague,
  • Edgar Sánchez
Universidad Nacional Agraria La Molina

Corresponding Author:[email protected]

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Eduardo Oyague
División de Limnología CORBIDI Lima Peru
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Edgar Sánchez
Universidad Nacional Agraria La Molina
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As in many other countries, Peru has the Water Quality Standard (WQS) as the primary tool for managing and diagnosing water resources. An analysis variable by variable to define water quality as poor or good was applied by setting concentration limits. A second group of tools commonly used are Biotic Indexes based on tolerance of benthic macroinvertebrates to pollution, that reflect the impacts caused by a group of variables, even though they cannot identify which variables determine the viability of the ecosystem. This research proposes to include the Stable States approach to evaluate the ecological integrity in central Andes rivers to explore an alternative approach with the capacity to represent a broader number of factors through multivariate analysis. A ten-year database of biological and physical-chemical variables measured in five Andean rivers were evaluated. Our results suggest these rivers fluctuate into two seasonal stable states (wet and dry season), accounting for approximately 31% of the system variability. In the wet season, the equilibrium of the state was dominated by the highest levels of suspended solids, turbidity, coliform, phosphorus, and some metals. During the dry season, the key variables were dissolved oxygen, flow, physical habitat, and biotic and diversity indexes. Likewise, there seems to be a third alternative state influenced by human pressures because of variables that exceed the WQS. Regarding water quality, the concentrations of coliforms, phosphorus, and lead usually exceeded the limits in two stations, but not every year. The ecological condition was better represented by ABI index than EPT.
24 Aug 2021Submitted to River Research and Applications
24 Aug 2021Submission Checks Completed
24 Aug 2021Assigned to Editor
08 Sep 2021Review(s) Completed, Editorial Evaluation Pending
08 Sep 2021Reviewer(s) Assigned
13 Feb 2022Editorial Decision: Revise Major
13 Apr 20221st Revision Received
16 Apr 2022Submission Checks Completed
16 Apr 2022Assigned to Editor
16 Apr 2022Review(s) Completed, Editorial Evaluation Pending
17 Apr 2022Reviewer(s) Assigned
20 Apr 2022Editorial Decision: Revise Minor
27 Apr 20222nd Revision Received
02 May 2022Submission Checks Completed
02 May 2022Assigned to Editor
02 May 2022Review(s) Completed, Editorial Evaluation Pending
03 May 2022Editorial Decision: Accept
Sep 2022Published in River Research and Applications volume 38 issue 7 on pages 1305-1320. 10.1002/rra.3993