Biome and ecosystem | Environmental science homework help

Pick a biome and ecosystem and create a 500-700-word essay addressing   the following:

1. Refer to the infographic provided and chose a biome to     describe with an example ecosystem. 
2. Provide one     example of a keystone species found in the biome/ecosystem.      Why is this keystone species important to the biome/ecosystem?      What defines it as a keystone species?
3. Provide an example     of an invasive species found in the biome/ecosystem.  What are     some of the negative impacts this invasive species has on the     ecosystem?  What is being done to mitigate impacts?
4. Provide one example of an endangered species found in the     biome/ecosystem.  Briefly discuss the causes of the decline in     the species and what is being done to help.   

Please include at least three academic sources and make sure   all sources are cited in your essay.