Mangaluru: Environmental activists from the city have opposed all developmental projects that involve felling of trees and which lead to an ecological imbalance. They were expressing their opinions on the National Highway Authority of India's (NHAI) decision to cut down 99 trees for the expansion of a stretch of the highway, from KPT to Nanthoor, at a grievance redressal meeting organized at the Range Forest Office at Hoige Bazar in Mangaluru on Monday.