Ecosystems - 06/09/17

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Biotic and Abiotic factors

An ecosystem is the area where living organisms and non-living conditions interact with each other.

Why do we need to maintain biodiversity?

Aesthetic - Artists, musicians and writers get inspired by areas with high biodiversity. It makes people happy.

Economic - Resources are used for medicines, etc and used for trading. Areas rich in diversity are thriving with tourism.

Ecological - Important for keystone species and maintains ecosystems and habitats.

Abiotic factors

Soil pH - Causes soil erosion if increased. Any change can disrupt enzymes which intern affects metabolism.

Temperature - Species will migrate away from the area to warmer/cooler climates if they change. Also can cause flooding due to ice melting, etc. It also affect enzymes and metabolic reactions. Temperature changes causes a change in seasonal species movement. Also it can trigger early migration as well as blossoming and leaf fall.

Light intensity - Affects photosynthesis. Plants grow taller and with bigger leaves to maximise sunlight intake in densely populated areas.

Humidity - Increased humidity encourages bacteria and fungi growth which causes disease.

Oxygen - This is in terms of water. Moving water contains more oxygen. The colder the water, the more oxygen it has. Water logging is a problem for organisms too.

Edaphic (soil) - There are three types of soil: clay, loam and sandy. Clay: contains very fine particles which clump together. Loam: good for growing plants. It contains different sized particles ideal for growth. Sandy: Well separated particles, easily eroded.

Biotic factors

Disease - Food chain disruption.

Invasive species - Introduces disease. They create competition, compete with native species. Such as shrimp in Grafham, red squirrels, and goats in the Galapagos.

Reproduction - More species, more competition for mates, food and territory.

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Explain why abiotic factors have a greater affect on the plant species than on animal species in an ecosystem.

Animals are able to migrate to cooler/warmer conditions if there is a temperature change, unlike plants, meaning they are affected by temperature change.

Animals can move to find shelter/search for water.

Plants can't regulate their internal temperature so are more affected by temperature change than animals.

Many animals are able to survive using a range of food sources unlike plants, meaning they are less affected by a decline in a certain species.