2.2 Measuring abiotic components of the system
Dec 28, 2015
2.2 Measuring abiotic components of the system
2.2.1 List the significant abiotic (physical) factors of an ecosystem.
2.2.2 Describe and evaluate methods for measuring at least three abiotic (physical) factors within an ecosystem
Ecosystems can be divided up as:
Marine – Sea, estuaries, salt marshes, and mangroves due to high salt content
Freshwater – Rivers, lakes, and wetlands
Terrestrial – Land-based
Marine Factors: Salinity pH Temperature Dissolved
Oxygen Wave Action
Freshwater Factors:
Turbidity pH Temperature Dissolved
Oxygen Flow Velocity
Terrestrial Factors:
Light Intensity Wind Speed Temperature Particle Size Slope/Aspect Soil Moisture Drainage Mineral Content
Light: Equipment: A
light meter Method: Multiple
times a day with same direction and angle. Must not be shaded.
Temperature: Equipment:
Digital Thermometer
Method: For air, water and soil. Soil needs to be standard depth, not too shallow.
pH: Equipment: pH
Meter or probe Method: Cleaned
between readings, and at same depth. Soil uses soil test kit – indicator added and compared to chart.
Wind: Equipment:
Anemometer Method:
Observing objects and relating to beaufort scale. Don’t block wind. Gusty wind may cause variations.
Particle Size: Equipment:
Sieves Method: Large:
Individually measured and averaged Small: Sieves Smallest: Sedimentation Optical: Light scattered by suspension
Slope/Aspect: Equipment:
Clinometer / Compass
Method: tangent of slope x 100
Soil Moisture: Equipment:
Scale and oven Method: Mass
before and after heating. Not too hot, and keep final mass after stabilized after heatings.
Mineral Content: Equipment:
Scale and Oven Method: Mass
before and after heating. Very hot (500-1000 C) for hours. Depends on minerals.
Flow velocity: Equipment:
Floating Object or flow-meter
Method: Object is timed. Meter is inserted just below surface for several readings. Taken multiple parts and times of year.
Salinity: Equipment:
Datalogger or calculator
Method: Measure electrical conductivity. High salt content is higher density than lower salt content.
Dissolved Oxygen: Equipment: Oxygen
sensitive electrodes or test kit
Method: Avoid oxygen in air. Kit based on oxygen reacting with iodide ions, and acid added to release them.
Wave Action: Equipment:
Dynamometer Method: Measures
force of waves. Average results must be taken due to changes in tide and wave strength over time.
Turbidity: Equipment:
Secchi disc Method: Put to
depth where it just disappears. Avoid glare, and use shady side of boat.