Using Single-Species and Whole Community Stream Mesocosm Exposures for Identifying Major Ion Effects in Doses Mimicking Resource Extraction Wastewaters.

Wastewaters and leachates from various inland resource extraction activities contain high ionic concentrations and differ in ionic composition, which complicates the understanding and effective management of their relative risks to stream ecosystems. To this end, we conducted a stream mesocosm dose-response experiment using two dosing recipes prepared from industrial salts. One recipe was designed to generally reflect the major ion composition of deep well brines (DWB) produced from gas wells (primarily Na, Ca, and Cl) and the other, the major ion composition of mountaintop mining (MTM) leachates from coal extraction operations (using salts dissociating to Ca, Mg, Na, SO and HCO)-both sources being extensive in the Central Appalachians of the USA.

Harmful Algae Bloom Occurrence in Urban Ponds: Relationship of Toxin Levels with Cell Density and Species Composition.

Retention ponds constructed within urban watershed areas of high density populations are common as a result of green infrastructure applications. Several urban ponds in the Northern Kentucky, USA area were monitored for algal community (algae and cyanobacteria) from October 2012 to September 2013. Many of the harmful algal blooms observed during this study were composed primarily of the cyanobacteria genus, No correlations were observed between basic water quality parameters (dissolved oxygen, pH, conductivity, temperature, nitrate and soluble reactive phosphate) and the presence of cyanobacteria and/or microcystin cyanobacterial toxin levels.