Ecosystems and Communities

An Ecosystem is a community of living things that interact with the non-living things around them:

• There are two main parts of an Ecosytem, the Biotic part and the Abiotic part:
  • The Biotic part is the section of the ecosystem thats made up of living things.
  • The Abiotic part is the section made up of non-living things like rocks and energy.
• Ecosytems can range in size, they can be as big as a forest, or as small as the area under a rock.
• A Habitat is where a living thing lives, organisms must get the things they need to survive with from their habitat.
• A Niche is the role an organism has in its Ecosystem. Such as where it lives and ho it behaves
  • Two organism cant live in the same , this is beacuse they will fight over food and space.
• Many Ecosystems are being threatend because of humans, pollution and climate change.

Ecosytems are dependent on the following abiotic (non-living) factors in order to function:

• Climate = If the temperature and rainfall in an Ecosystem is too high or low, then certain species wont be able to survive. This is why Ecosystems with different climates, E.g, a lake and a desert, have different species inhabiting them.
• Soil = different types of soil provide different types and amounts of nutrients for the plants.
• Water = The amount of water in an Ecosystem will ditermine the types of species and plants living in it.

In order to sustain a good Ecosystem, there is a very particular way that the abiotic and biotic components interact.

• The food chain in the Ecosystem is a way for everything to survive. The producers of a food chain, like the grass, make there own nutrients and provide as a food source for the primary consumers.
• This cycle is followed by the secondary and tertiary consumers, who feed on the chain before them.
• Food webs are more complex food chains.

Ecosystems go through many changes over time. The different types of factors that contribute to Ecosystem changes are Natural and Human factors:

• Natural factors that can affect Ecosystems include:
  • Fire
  • Drought
  • Floods
  • Disease
• Human factors that affect Ecosytems include:
  • Pollution
  • altering the nutrient levels of the water if fertilisers are leachedinto the water resulting in eutrophication.
  • changing the Ph of the water.
  • introducing more fish to the Ecosystem
• Certain changes in the Ecosystem can be bad and cause a collapse in its food chain.

Places with different Latitude, Winds, Air pressure etc, effect the placement and climate of an Ecosystem.

• Latitude = places with lower latitude, like the topics, have higher temperatures. This is because the sun's rays travel a shorter distance to the Equator and are therefore more concentrated. Consequently, places with higher latitude are colder. So different places within these Ecosystems will have many differences between them. 
• Winds = Ecosystems with high pressure are generally more warm and dry, so an Ecosystem in a place with high pressure will look different to one with lower pressure.
• Air pressure =  Differences in air pressure also mean differences in rainfall and temperature, so Ecosystems with different air pressures will look different and have different species that live there. 

Ecosystems gradually change from the Equator to the poles.