Without human intervention

Does "that these systems could be sustained indefinitely without human intervention" in the following context mean:

1. that without human pollution and destructive activities natural ecosystems would live forever i.e. even if human did not exist these ecosystems would not live forever.

or

2. that without human's assistance natural ecosystems would live forever i.e. if human does not help the nature its ecosystems will die.

or

3. that without human correcting his faults (pollution), natural ecosystems would live forever i.e. if human does not correct his faults ecosystems will die.

Context:

This group included the West German artist Hans Haacke, whose early systems-oriented works Grass Grows (1969) and Rhinewater Purification Plant (1972) strove to set in place an artwork that was beyond objects, since because of its defining tie to the mutability of the environment, it could itself be “something which experiences.” But these organically based works also pointed to the fragility of ecological systems.In his Rhinewater piece, Haacke implicitly criticized the public’s incorrect assumption that these systems could be sustained indefinitely without human intervention.Working in collaboration, the artists Helen Mayer Harrison and Newton Harrison would raise this issue of sustainability more explicitly in their installations of the 1970s and 1980s.