Chronic toxicity of ammonia to New Zealand freshwater invertebrates : A mesocosm study

• Published in: Archives of environmental contamination and toxicology Vol. 37; no. 3; pp. 338 - 351
• Main Authors: HICKEY, C. W, GOLDING, L. A, MARTIN, M. L, CROKER, G. F
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer-Verlag 01-10-1999; Berlin Springer Nature B.V; New York, NY
• Subjects: Ammonia; Animal, plant and microbial ecology; Applied ecology; Aquatic insects; Biological and medical sciences; Chronic toxicity; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Environmental conditions; Freshwater invertebrates; Fundamental and applied biological sciences. Psychology; Invertebrates; Macroinvertebrates; Protected species; Taxa; New Zealand; Oceania; Community structure; Artificial stream; Fauna; Toxicity; Concentration; Freshwater environment; Ammonia; Biotic integrity index; Pollutant; Animal community; Macrofauna; Water pollution; Invertebrata; Population density; Animal passive transport; Species richness; Organic compounds
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s002449900523

Freshwater macroinvertebrate communities were established within 12 artificial streams or "toroidal" mesocosms and exposed to three replicated concentrations of ammonia for 29 days at constant temperature (16 degrees C) and pH (median 8.4). The criterion units (CU = measured [ammonia]/US EPA 1985 chronic criterion value) of total ammonia in the LOW, MED, and HIGH treatments were 2.0, 4.8, and 13 CUs respectively, and 1.9, 5.8, and 12 CUs for the unionized ammonia. Macroinvertebrates were tolerant of the ammonia exposures with no significant (p > 0.1) effect on taxa richness; number of taxa in the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT); or the quantitative macroinvertebrate community index (QMCI), a biotic index proposed for assessing effects of organic enrichment in New Zealand streams. Significant differences (p < 0.05) occurred for the mean abundance and the numbers of EPT individuals (QEPT), with the HIGH treatment significantly lower (-41%) than the control for both abundance and QEPT. Of the major species, only the mayflies Deleatidium sp. (Ephemeroptera: Leptophlebiidae) and Coloburiscus humeralis (Ephemeroptera: Oligoneuriidae) showed significant reductions in abundance, with only the caddisflies Beraeoptera roria (Trichoptera: Conoesucidae) and Confluens sp. (Trichoptera: Conoesucidae) showing significant increases in abundance. The abundance of juvenile Deleatidium sp. had a negative concentration-response relationship that resulted in an 82% decrease in abundance in the HIGH treatment. Drift of invertebrates showed no response to ammonia treatments. The 29-day EC(50) values for Deleatidium sp. for total and unionized ammonia were 2.15 mg (N)/L (pH 8.4) and 0.145 mg (NH(3)-N)/L. No observed effect concentration (NOEC) values were 0.95 mg (N)/L and 0.066 mg (NH(3)-N)/L, and the threshold effect concentration (TEC) was 1.49 mg (N)/L and 0.102 mg (NH(3)-N)/L. Comparison of the Deleatidium sp. chronic ammonia sensitivity data with the US EPA 1985 chronic criterion value (CCC = 0.45 mg [N]/L, pH 8.4, 16 degrees C) showed the TEC value for total ammonia was 3.3x CCC, and 2.2x higher than the updated US EPA 1998 criteria. The findings suggest that use of the US EPA criteria would provide minimal protection for Deleatidium for chronic ammonia exposure, and that development of site-specific criteria, covering a wide range of environmental conditions, may be required to adequately protect this species.http://link.springer-ny.com/link/service/journals/00244/bibs/37n3p338.html