I'm going to ditto the theory that the first cuts are for grades in many instances. I hope your grades are high enough that you won't even have to worry about GPA cuts!
Most schools have some kind of PNM manual or cd-rom about recruitment and each chapter where the sororities list a "minimum" GPA for their chapter. That may be as low as a 2.0 (if their International states that as an absolute minimum) and could be as high as a 2.75, 3.0 (or even higher, I guess, but I think the highest I've ever seen printed was a 3.0.)
Reality is that even if the chapter says their minimum is a 2.0, 2.25, 2.5 or whatever; their actual target GPA is considerably higher. Take a look at the grade ranking for the sororities on your campus, if available. That will give you a much more accurate picture of each sorority's academic goals.
Here's an example--XYZ lists their minimum GPA is a 2.5, and rank 6 of 12 sororities last year in grades, with a chapter GPA of 3.24. Most likely, XYZ is looking for PNMs with 3.25 and higher GPAs. They may bid a couple new members in the 2.9-3.0 range if their overall grades and membership are solid enough to take a few "grade risks." On many competitive campuses, if your grades are under the all-sorority average, a PNM may have an extremely difficult time getting a bid. Not impossible, but grades are an important part of sorority life these days (as they should be!)
When there are hundreds or even thousands of girls going through recruitment, the sororities have to cut somewhere. Often, grades are the first cut because it's the easiest--no emotions involved, just cold hard facts.
AMelie, have you searched the UNL website? Look for links to each sorority and see what you can learn about them (grades of course, new member and recruitment info, chapter activities, campus and community involvement. Check out the International websites for each sorority too. Do you like what you see? Seriously, the more you know about each sorority at UNL, the more informed of a decision you can make for yourself.
Stay calm (I know, easy for me to say as an alumna!) and breathe deep
You'll be ready to make a lot of friends and have fun during recruitment. We'll do our best to support you every step of the way!
Christin