Eco damage at a base is caused by terraforming and by mineral prodcution. Each terraform existing in a bases radius does some increment to the base eco impact, usually small except for boreholes and condensers. Each mineral produced for the base, except by satilites and some secret projects over a base 'mineral immunity' number causes eco damage. Your planet rating can magnify or reduce eco effects. To build up your 'mineral imunity' number (which starts IIRC, at 16, you need to build "green" facilites (tree farms, hybrid forests, centauri preserves, and temples of planet) AFTER YOU HAVE SUFFERED your first eco damge fungal bloom 'pop'. EACH of these facilities you build at ANY base thereafter increases the mineral immunity for ALL your bases. Eco damage from terraforming is usualy less the minerial production eco damage, but is reduced at each base that builds tree farms and/or hybrid forests. Centauri preserves and temples of planets increase the planet rating for calculating the eco damge at base where they are located. To go back to mineral immunity, it is important to get you first fungal pop early by building up the mineral procution at one base with mines and supply crawlers, and maybe running social enginering to lower your planet rating. After you get that first pop, you switch to more planet freindly SE and build tree farms and centauri preserves like mad.
