4. The uneven distribution of resources has many effects on human populations. What are the six key areas. Explain each one.

I don't know what the six key areas

Water flows along the east coast and across the western tropical pacific towards south america, while they both are directed towards that way,  el niño does not directly affect the southern flow of water along the coast. 

Answerhave flowing water either episodically or during only a portion of the year;

The answer is i believe low birth rights.hope my answer is the one you are looking for : )

Answer erosion,oil spills,pollution,tourism,urban development;