procedures

• Survey a designated segment in Molawin Creek, designate two stations: riffle (highest velocity) and pool (lowest velocity); note the distance between each station
• At each station do the following:

  • Measure stream velocity (m/sec) using the pingpong ball
  • With a stopwatch, determine the time it takes for the ball to traverse the distance of 1m. Convert measurements into m/s
  • Determine some of the stream's physico-chemical characteristics using analytical methods/instruments. Have three replicate readings for each parameter per station and record the results on 4C.1
  • Characterize the nature of sub-stratum of the assigned station starting from the station most down stream
• Plankton collection and identification

  1. Dip and raise the plankton net 20 times in the pool segment

  2. Place the orifice of the plankton net against the flow of the water for 5 minutes in the riffle segment

  3. Collect the concentrated plankton sample in a 200ml screw-capped collecting jar/bottle

  4. Add Lugol's iodine as a fixative

  5. Bring the samples to the lab, take an aliquot of the mixed sample and mount this on a glass slide with cover slip

  6. Examine under the microscope

  7. Use the references provided by your instructor for guidance in the identification of species seen under the microscope
• Table 4C.2

  • Organisms observed
  • Adaptive features of the organisms that enable them to thrive suspended in the flowing water
• Aquatic microflora and fauna identification

  • Observe the aquatic macrophytes and animals in each station and in the riparian zone
  • List the names of the organisms observed in table 4C.3