Tuesday, March 26, 2013

How We Analyze Ions

“A process of critical thinking that uses observations and experiments to investigate testable predictions about the physical universe.” By using the scientific method throughout our class experiment we have attempted to dissect the more complex issue into smaller parts to help us better understand our experiment and purpose.  We want to know does this high resolution small scale experiment help us understand trends for the large scale rivers that serve as tributaries to Buck Creek. The steps of the method we have used in our tests are choosing a guiding question to go along with our controlled experiment to seek out the big picture in our study.  Our hypothesis or guiding question is by examining Buck Creek and its surrounding wetlands does the water quality improve with increased nitrogen and more organisms as the water travels its course through the sub-tributaries of the river. To investigate our hypothesis we have put in place procedures of sampling and recording our results to put together a data set we can show and interpret at GSA. 

We have collected ion concentrations by using an automatic sampling ion chromatograph(pictured above).  An ion chromatograph analyzes the concentrations of various ions that are in the samples.  This is done by using standard solutions that we create with concentrations within the expected range for each ion.  The chromatograph then uses these standard solutions to create an equation to find the concentrations of the unknown samples.    As the sample travels through the machine each ion travels at different speeds and the machine measures this speed and produces peeks(sample peaks pictured below).  The area is then found and can correlate to what the concentrations of the ions are. 

With the small scale data we can observe how our local impact is affecting the larger tributaries such as the Ohio and Mississippi Rivers.

-Beth and Grant

Sources used:

1 comment:

  1. We might not see an impact from our small watershed on the larger watershed, but we can better understand how these ions are altered as they travel through the stream & wetland. This gets harder as the landuse contributing to larger watersheds is more varied.