In order to protect Queens Park there are two sections which allows dogs in one area and not in the other, conserving the grass in the eastern part of the park. If dogs are taken into the exclusion zone a fine is the penalty as stated by The Clean Neighborhoods and Environment Act 2005.

https://www.brighton-hove.gov.uk/sites/brighton-hove.gov.uk/files/downloads/2012/The_Professional_Dog_Walkers_Code.pdf