This website contains age-restricted materials including nudity and explicit depictions of sexual activity.
By entering, you affirm that you are at least 18 years of age or the age of majority in the jurisdiction you are accessing the website from and you consent to viewing sexually explicit content.
Alternative in what sense?
Pretty sure some cities have about zero areas for a tree to grow. Algae produces a much larger percentage of oxygen compared to any tree.
Pretty sure trees in cities aren’t there to produce oxygen or capture carbon.