Publishing academic research in more than one field I have an important question, so please try to answer it precisely and carefully as possible.

If I want a career in one field in academia, would it be inadvisable to publish some other academic researches in other fields. 

I have seen an article in a blog that suggest against it. But on the other hand I think that ability to publish research and practise this process is important for academic persons.

Nevertheless, lately I browsed Shanghai ranking and they have a rule that divides the researcher contribution by the number of departments they published in.

To expand my point,for many fields it is necessary to combine expertise from different disciplines in order to sythesis some new approaches. So frankly, I really do not understand the logics behind such an archaic approach.

So the question is, will it help publishing in more than one discipline or will it really make everything more difficult?
Interdisciplinary research is both an advantage and a disadvantage.  

Interdisciplinary research is advantageous because the interaction between fields is often extremely productive in creating new knowledge and breakthroughs.  Lots of extremely important things start out as interdisciplinary research, and it's where entire new fields tend to emerge.  In my opinion, most of the most exciting research you'll encounter is interdisciplinary in nature.

The disadvantage is that until the new area starts to be recognized as important, interdisciplinary work isn't well "claimed" by any discipline.  This means it's harder to get published, harder to get funded, and generally harder to get respect from colleagues working in "core" areas.  There are often very few people who fully understand the content of an interdisciplinary project, and the importance of an interaction is often only recognized in retrospect.

This tension is, I believe, the reason that you often see articles calling for more interdisciplinary research.  Many people recognize its importance, but if it was well-supported by existing community dynamics, they wouldn't need to write these articles.