Too many links in page head

Hi,

here's the screen: https://postimg.org/image/4sz7knr6l/.

I'm looking for ways to stop so many links appearing in the head of my website. I don't feel I have control over this - no idea why so many of them are generated, I only have about three I see hard coded, all other appear out of nowhere. I understand some of them are generated by plugins, but could anyone help me with switching off as many of them as possible?

and why so many css files? Is there a method to move some of them down or join them into one big css? I think it must really slow down page load.

thanks
kat