Across:
   1. Concerned with the web of life as cool glacier mostly melted (10)
   7,16dn. Judge Who 'ten' (listen carefully for their bass player!) (4 9)
   9. Pact broken with manic heir being less consistent (8)
  10,28. Alas, mark hair styling for female politician (6 6)
  11. New leaf for bass player (4)
  12. Stop for bride; come in finally for groom (5)
  13. Play early part in Four Seasons (4)
  14. Hope pear is diced (6)
  15. Correcting final words in ballad: "Ned daringly returned" (7)
  17. Where 15 across found in book found in 15 across? (3)
  18. see 21 down
  21. Poor set in jam, which could get thrown away (6)
  24. Cut sticks up (4)
  26. Primarily seasonal worker, a jovial one (5)
  27. see 2 down
  28. see 10
  29. Mathematical statement mangled in a quote (8)
  30,25dn. King and Harry losing head over sort of musician (4 5)
  31. Winding slender pit divided, going several ways (10)
Down:
   2,27ac. Cleaner survives taking tips from enormous popular musician (7 4)
   3. Developed vital cure, making lots of dough (9)
   4. Walks awkwardly in case of gaffe (showing little bit of spotting) (7)
   5. see 7 down
   6. Compared with Livingstone, was dishonest all round (7)
   7,5. Running around close to Tom cat, I'm Jerry, the boss! (5 6)
   8. Country of lax liberal leaders taken in hand (7)
  15. Latin prefix commonly used in hexadecimal (2)
  16. see 7 across
  17. Latin prefix commonly used in hexadecimal (2)
  19. Barbara in Ohio holds back Pacific capital (7)
  20. Maintains suzerains; is tsar so accommodating? (7)
  21,18ac. Actor "wrestling with tiger to become hero" (a Xi Jinping quote) (7 7)
  22. In Australia, we so meaningfully exclaim this! (7)
  23. Beheaded bull, embracing strange new "sick" (6)
  25. see 30 across