Environmental changes

• the biodiversity and distribution of organisms within an ecosystem is due to both abiotic and biotic factors
• Biotic factors:

  -Availably of food

  -Number of predators

  -Presences of disease caused by pathogens.
• Light intensity is linked to photosynthesis- this can be measured using a light meter. errors can be made when measuring light intensity by accidentally shading the light.
• Temperature is linked to the speed of enzyme controlled chemical reactions- this can be measured with a thermometer- temperature probe. Digital thermometers are more accurate then traditional thermomotors.
• Moisture levels - a rain gauge can be used to measure rainfall and a humidity sensor can be used to measure moisture levels.
• Soil pH is linked to the speed of enzyme controlled chemical reactions. Universal indicator can be used to measure the pH of a soil sample, but a pH meter is more accurate as it does not rely on human judgement. Errors can be made when measuring pH and soil moisture when probes are not cleaned between readings.
• Oxygen levels are linked to aerobic respiration - an oxygen meter can be used to measure how much oxygen is present in lakes and rivers.
• abiotic factors:

  -Light intensity

  -Temperature

  -Moisture levels

  -soil pH

  -oxygen levels.