Different Ads According To URL Parameters

Very simple to do.

If there is one page (url) or only few pages for each parameter then you can whitelist them for specific block, for example:

/page1.php?src=email

If there are many pages for each URL parameter (query) then you can write a simple PHP code to extract the parameter and display code block accordingly.

For example, you put the following code to block 1 and enable PHP processing for this block:

<?php
if (isset ($_GET ['src'])) {
  switch ($_GET ['src']) {
    case 'email':
        echo adinserter (2);
        break;
    case 'facebook':
        echo adinserter (3);
        break;
    case 'twitter':
        echo adinserter (4);
        break;
    default:
        echo adinserter (5);
  }
}
?>

Then you put ads in blocks 2 (email), 3 (facebook), 4 (twitter) and 5 (default), enable PHP function adinserter for them and use code block 1 for automatic placement.

This is just an example to give you a hint, you should write the code according to your needs.