What are the advantages and disadvantages of general research which is case study based and more generic (problem) research which can be applied to different climatic/physiographic settings?
Generic, as you refer to it, research involves the isolation of individual variables to understand their effect, typically in a lob or other controlled setting. However, this is not the real world case, and sometimes the effect in isolation does not perform the same as it does in a complex system. Therefore case studies, which observe the entire complex system, come in to play to see how things actually work in real life.
They both have their strengths and weaknesses. In isolation you can observe the effect but out of context. In case study you are observing the context but it can be very hard to see the effects amongst the complexity.