Natural ecosystems

Abstract

After you have read this chapter you should be able to:

• describe the main components of an ecosystem and the main processes that take place in it

• identify the abiotic factors in an ecosystem

• compare aquatic and terrestrial habitats

• identify the biotic components of an ecosystem

• describe the different kinds of ecological interactions in an ecosystem

• describe a food chain and a food web

• explain the structure of a biotic or trophic (food) pyramid

• explain how energy flows through an ecosystem

• describe the carbon and nitrogen cycles

• describe the water cycle

• understand the balance between photosynthesis and respiration

• describe the growth of a population and the effects of limiting factors

• understand that the microorganisms in an ecosystem affect other living organisms in a variety of ways