The communities have these different traditions to represent their cultures. Most Singaporeans are members of other communities in South East Asia, and they have brought aspects of those cultures to Singapore, which I believe adds to the overall atmosphere and culture there.
These traditions are not connected to the environment, but rather to the region and its people. I was able to learn this music by taking a class titled "Social and Cultural Studies Through Music", which helped put the music in context with the culture that created it.
I have put together a few extra YouTube videos for you to learn more about the music!
Here is my teacher reciting rhythms for classical Indian music:
https://www.youtube.com/watch?time_continue=2&v=iDzXVwpWV4E&feature=emb_logo
Here is my teacher playing the kacapi:
https://www.youtube.com/watch?time_continue=1&v=EhjZX8fAt2A&feature=emb_logo
And here is some Chinese New Year drumming!
https://www.youtube.com/watch?v=G_FIpEfgumI&feature=emb_logo