2.2 Measuring abiotic components of the system. 2.2.1 List the significant abiotic (physical)...

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.