Environmental Factors Affecting Living Organisms

Environmental Factors (Terrestrial)

• Abiotic factors: non-living factors e.g. aspect: north-facing slopes are cooler and darker than south facing slopes in Northern hemisphere
• Biotic factors: living factors, e.g. food availability: more food will enable more organisms to live
• Climatic factors: effects of weather, e.g. rain: more rain means more water, which supports more life
• Edaphic factors: effects of soil, e.g. soil pH: pH affects growth of particular plants as pH affects enzyme action

Environmental Factors (Aquatic)

Aquatic habitats have unique problems in comparison to terrestrial habitats. These problems include:

• Light penetration e.g. plankton grows better in the upper layers of water due to higher light intensity.
• Currents transport organisms. Plants & animals subsequently get washed away unless they attach themselves to objects (e.g. limpets and many seaweeds).
• Wave action moves and damages organisms
• Salt content results in organisms adapting to freshwater or saltwater. This causes issues with water moving in or out of organisms and their cells. Limpets live in seawater, not freshwater.  Organisms in seashore ponds must be able to withstand changes in salinity (due to rainfall and evaporation).
• Oxygen concentration is lower.
• Tides e.g. the amount of time organisms are exposed or submerged. Shore plants lose water at low tide. Organisms on shore have shells or mucilage to retain water (The Physics Teacher, 2018).