Mountain Research Station – University of Colorado, Boulder.

The Effects of Chemical and Physical Factors of Streams on Aquatic

Invertebrates

Carissa FisherWinter Ecology

Spring Semester 2010Mountain Research Station – University of Colorado, Boulder

Introduction

The goal of the study was to look at the different numbers and species of Aquatic Invertebrates living in winter streams in the Rocky Mountains.

http://www.mbgnet.net/fresh/slide/pict/19.htm

Questions Does the Stream Morphology and Chemical

Composition play a huge roll to the life of Aquatic Invertebrates living there through the winter?

Do many Aquatic Insects inhabit the Streams throughout the winter season?

Hypothesis: How do factors of dissolved O2, pH, temperature, elevation, and TOC (Total Organic Carbon) affect the species richness, and species density of aquatic invertebrates in fresh water streams during the winter?

Stream Selection

Streams Located on Same Mt. in Similar areas

Known and similar elevation between streams

Known Order of Stream Similar Stream

Morphology Similar Slope

Location of Streams

Site 1 WCC

3050’

Site 2 WCC

2900’

Site 3 CC2800’Site 4 CC

2700’N

S

EW

Headwaters of WCC

Headwaters of CC

Sample Site 1 West Chicago Creek The stream was more narrow here and

it was much more protected by the snow. There was rich sediment in the bottom of the stream here.

Sample Site 2 West Chicago Creek This site was closer to peoples personal

land and that may have affected the water quality. The stream here begins to get wider and is still protected by snow.

Sample Site 3 Chicago Creek Here the Stream is wider, pebbles and

rocks make up the bottom. There is much less organic Material here, and the vegetation is Conifers instead of predominantly willow.

Ice dominates the stream.

Sample Site 4 Chicago Creek Here again the dominant vegetation is

willows. The stream is at its widest and the bottom is covered with rocks. The stream is covered with ice.

Sample Collecting Techniques

pH Probe Temperature Probe Water Sample Collection Strainer to collect Aquatic Inverts Send the Samples to Louisville Water Lab

Data Analysis Toolsat Louisville

Laboratory TOC Analyzer Multifunctional Probe : Chlorophyll, Dissolved O2, TDS

Turbidimeter

Results

I was able to collect 2 samples from each stream. These are represented on the graphs on the next page.

Each sample was tested for: Temp, pH, TOC, DO, Chlorophyll, and Turbidity

-0.2 0.8 1.8 2.8 3.8 4.8 5.8 6.8 7.8 8.8 9.8 10.82700

2750

2800

2850

2900Chicago Creek Temperature C

pHDissolved Oxygen mg/LTotal Organic Carbon mg/LChlorophyll mg/LTurbidity NTUInsects Found #'s

Ele

vati

on

'

-0.2 0.8 1.8 2.8 3.8 4.8 5.8 6.8 7.8 8.8 9.8 10.8290029202940296029803000302030403060

West Chicago Creek Temperature CpHDissolved Oxygen mg/LTotal Organic Carbon mg/LChlorophyll mg/LTurbidity NTUInsects Found #'s

Ele

vati

on

'

Similarities Between Graphs

Temperature goes down by less than a degree as elevation drops in both streams

The TOC goes up a fraction as elevation goes down, this is almost negligible.

Differences Between Graphs

In Chicago Creek there is no chlorophyll or insects found. While in WCC both the chlorophyll and # of insects found increased with elevation.

In WCC the DO is lower at higher elevations, while in CC it is stable throughout

Turbidity decreases with elevation in CC but increases with elevation in WCC

Insects Found: I wasn’t able to identify this insect however if slightly resembles beetle larvae. Found at Site 1.

This Insect is likely a Stonefly Larvae – They feed on plant matter and TOC. They live in the benthic area of streams. Found at Site 1.

This insect began to decompose before I was able to identify it. However it is likely a Stonefly Larvae or a Mayfly Larvae- They cling onto rocks in the bottom of streams and also eat detritus and plants. Found at Site 2.

Discussion and Conclusions

The main question I was looking at is pretty inconclusive. I didn’t collect enough data to show aquatic insect species diversity in CC.

I did find that CC had less Chlorophyll and I didn’t find any insects there. So it is possible that there is a correlation but more testing is necessary to find out for sure.