Complex sentence: Seedling survival for the species is lower than for banksias which regenerate by seeding over time, but the longevity of mature plants allows for maintenance of population despite poor recruitment until favourable years enable better survival of young plants.
Split into simpler sentences: Seedling survival for the species is lower than for banksias which regenerate by seeding over time. Despite this, the longevity of mature plants allows for maintenance of population until favourable years enable better survival of young plants.