What is an ecosystem?
An ecosystem includes all the living (biotic) and non-living (abiotic) parts in an area. Organisms in an ecosystem can be classed in one of 3 ways: a producer, a consumer and a decomposer.
An example of a producer is grass. The producers are always at the start of the food chain since they provide their own energy (food) via a process called photosynthesis. This process enables them to make their own food in the form of glucose (sugar).
Consumers eat producers (herbivores) but you also get consumers who eat other consumers (carnivores). These organisms cannot produce their own energy/food, so they have to consume producers or other consumers.
A decomposer is a microorganism which breaks down dead organisms and remains into smaller parts and digests them in order to release the nutrients back into the soil. These organisms are vital because they play a key role in the nutrient cycle by recycling the nutrients in the dead organisms for a new one.
A food chain shows what eats what. A food web shows multiple food chains and how they link. It can be used to show the feeding levels in an ecosystem. The line shows what an organism is eaten by. Each stage in a food chain is called a trophic level. The amount of energy available to each trophic level decreases due to energy being wasted via movement and keeping an organism warm, this is why food chains are relatively short.
Some parts of an ecosystem depend on the others for their food source, e.g. consumers. If the conditions in the ecosystem change, it can have severe affects on the entire structure. Factors affecting a food chain: climate change, habitat change and pollution. A change in any of these factors can unbalance a food chain, which has knock on effects for other organisms, resulting in a complete change of…