Abstract
Benthic macroinvertebrate tolerance to water acidity in the Grande river sub-basin (San Luis, Argentina) Acidic stress induces multiple adverse effects on the benthic macroinvertebrate community. The methods used to assess the taxa tolerance limit are based on qualitative relations between species at different pH values. The aim of this work was to estimate the tolerance of benthic macroinvertebrates to water acidification. Four sampling stations were established in the sub-basin of the Grande River, three of them (G1 ,G 2 and G3) on the Grande River and one (C) in one of its tributaries, the Carolina Stream, which receives the acid drainage of an abandoned gold mine. Sample collection (n = 24) was carried out with a Surber net and recorded bimonthly between May 1997 and December 1998. The tolerance limit (TL), the optimal pH, the tolerance range (TR) and the acidification index (AI) were calculated for each taxon. pH values ranged between 3.6 and 9.6. Sixty eight taxa were identified and separated into three groups, according to the TL: > 5.5 with 50 %, an intermediate group with a value of 5.5 and the remaining ones (40 %) with values < 4.7. Several acid-sensitive taxa were not present in station C. Dipterans presented higher tolerance to acidity. The application of the acidification index (AI) resulted in category 1 (not acidified) in G1 ,G 2, and G3 and in category 0.5 (acidity episodes) in C.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
