HABITAT ANALYSIS II - AQUATIC
GENERAL ECOLOGY LABORATORY
Location: Burns Valley Creek and Gilmore Creek
Objective: Assess general habitat characteristics of two sites on
different streams in Winona
Hypothesis: Physical and chemical characteristics do not
differ between Burns Valley Creek and Gilmore Creek
Agenda:
1) General description of stream - watershed characteristics
(natural area, residential, agricultural, industrial, obvious
pollution sources), vegetation, animals present, weather conditions
2) Measurement of physical characteristics:
a) Take multiple measurements of width, water depth, water temperature, and conductivity (p. 54-58)
b) Determine the flow rate by measuring current velocities at 0.6-depth at 12 points spaced equally across a stream transect; record the stream width, the 12 velocity measurements, and the total stream depths where the velocities were measured
c) Determine substrate composition by identifying the major substrate types in square-foot patches across five or more stream transects. Use the following guide:
Bedrock - large mass of solid rock
Boulder - over 10" in diameter
Rubble - 2" to 10" in diameter
Gravel - 1/8" to 2" in diameter
Sand - less than 1/8" in diameter
Silt - fine material with little grittiness
Clay - compact, sticky material
Muck - decomposed organic matter, usually black
Detritus - organic matter, e.g., sticks, leaves, etc.
3) Measurement of chemical characteristics - Take multiple measurements of dissolved oxygen, nitrates, and hardness (p. 63-76)
Analysis:
1) Calculate means and standard deviations for width, depth, water
temperature, conductivity, dissolved oxygen, nitrates, and hardness,
and statistically compare the means between sites using two-tailed t
tests.
2) Calculate flow estimates (cubic meters per second) for each site.
3) Use a contingency table to compare substrate composition between the two sites.
Equipment:
Meter tapes, conductivity meter, meter sticks, bucket, digital
thermometer, current meter, DO meter, nitrate and hardness test
kits, waders!