Measuring Abiotic Factors

Each ecosystem has its own abiotic factors  Different factors for… – Marine ecosystems – Freshwater ecosystems – Terrestrial ecosystems

Marine Ecosystem abiotic factors  Salinity  pH  Temperature  Dissolved oxygen  Wave action

Freshwater Abiotic Factors  Turbidity  Flow velocity  pH  Temperature  Dissolved oxygen

Terrestrial Abiotic Factors  Temperature  Light intensity  Wind speed  Particle size  Slope/aspect  Soil moisture  Drainage  Mineral content

How?  Most of these measurements are done with dataloggers. – Probe connected to a calculator that reads the measurement

pH  7 is neutral  Values in freshwater range from slightly basic to slightly acidic  Seawater is usually above 7.  Terrestrial: use a soil testing kit, match color

Wind  Determined by the beaufort scale  Use an anemometer  Hand held wind propeller

Mineral Content  Weigh soil sample,  Heat C for several hours – Allows volatile substances to escape  Whatever is left is the mineral content

Flow Velocity  Time how long it takes a floating object to travel a particular distance.  Or use flowmeter

Salinity  Determine the conductivity of a solution (higher salt is highly conductive)  Or by density of water (higher salt-more dense)

Dissolved Oxygen  Electrodes  Titration  Dissolve tab

Turbidity  Cloudy water has high turbidity  Turbidity affects the penetration of sunlight and therefore the rate of photosynthesis  Use a Secchi disc -lowered into the water until it is out of sight, measure the scale of the line or pole.

Let’s try it!