How much Ecology in Biology M?

I’m taking the biology M SAT in about a week, and according to the college board, about 13-15% of questions on the test are ecology related. I’m just wondering how in depth and detailed I should know ecology info, especially since I’m taking the molecular test, and ecology/evolution are definitely not my favorite topics.

To what extent should I study the Ecological/Evolution topics (in the Barron’s and PR books)?
To give an idea, here’s a portion of my notes on ecology, the topic is Ecological Succession

Ecological Succession
Rebuilding ecosystems after destruction
Primary Ecological Succession occurs in a lifeless area with no soil
First organisms that appear are lichens and mosses (pioneer)
Decomposed material of pioneer organisms allow soil and rocks to weather
Final, complete system = climax community
Remains intact until another blowout
Secondary Succession is when an existing community has been cleared, but soil is intact, gets covered in new vegetation

Will this be sufficient? How should I go about tackling ecology/evolution topics?

Any advice would be greatly appreciated

Expect to see 1-4 ecology questions among the 60 general biology questions and 0 in the M section