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Email the author (Login required) Proposal of ecological flow at Ayuquila-Armeria River watershed in western Mexico
Submited: 2016-07-29 02:09:25 | Published: 2018-03-15 16:31:40
DOI: https://doi.org/10.3856/vol45-issue5-fulltext-17
Abstract
Rivers have experienced great changes in the last 100 years. In Mexico, measures have been taken to compensate for the damages caused, through the Mexican Standard NMX-AA-159-SCFI-2012, which establishes the procedure for determining the ecological flow. The watershed of the Ayuquila-Armeria River, one of the most important rivers in western Mexico, has suffered in recent years drying out, towards to the sea, which has been an obstacle for migratory species. The objective of our study is the proposal of ecological flow of monthly distribution, using the hydrological methods, combined with the use of the hydrobiological method, defined in the Mexican standard. As a result of hydrological methods totaling 1.088 hm3 year1 , the hydrobiological method estimates an ecological minimum flow of 4.5 m3 s-1, indicating that in spending levels below this flow the "target species" would not survive if flows fall below these levels due to significant decreases in their Weighted Usable Area (WUA). The final result is a monthly flow regime; during the dry season (November-May) it maintains a 7% water reserve, and for the driest months from March to May, 2%, with flow rates of 5 m3 s-1 in March, 4.5 m3 s-1 for April and 4.4 m3 s-1 in May, the protection of aquatic fauna was ensured, in rainfall from June to October it has a water reserve of 41%, reaching its highest flow in September with 105.3 m3 s-1 improving the hydrological and geomorphological dynamics of the river.
