An ecosystem has abiotic(no living things like water and wind) and also biotic(living things) while a community is biotic things
Construction of physical structures to protect coasts from erosive power of waves
Ocean water is most saline in dense seawater.
answer: b. in dense seawater.
The tilt of the Earths axis can affect where the Suns rays hit the Earth. If the northern hemisphere tilts slightly more than the southern hemisphere, the northern hemisphere is facing the sun more often, this is known as "Summer" for people in the north, and "Winter" for people in the south. Im not sure if that answered your question, but the suns rays bounce off the Earths surface and clouds and sometimes hit each other in our atmosphere.
