Although artists have long engaged with concepts of nature in the tradition of landscape, distinctly environmentalist artwork emerged in the 1960s in parallel with related social movements. Iconic Land Art projects by Robert Smithson and Christo and Jean-Claude were both celebrated for creating new spaces and audiences and critiqued for the damage they often inflicted on their environments. Perhaps in response, artists of succeeding generations have sought to explore the relationship between humans and the environment without damaging the latter. This is illustrated in such works as Richard Long's walks through remote territories and Andy Goldsworthy's ephemeral sculptures in nature. In 1982, Joseph Beuys initiated the planting of 7,000 oak trees throughout Kassel, Germany, as his contribution to “Documenta 7.” Contemporary artworks often use documentation to raise awareness of human-caused environmental degradation, as seen in photography by Edward Burtynsky and Richard Misrach, and in research-driven investigations of the systems governing social and natural ecologies, as in the work of Mark Dion. In the era of global climate change, new terminology sheds light on shifting priorities; scientists have proposed the term Anthropocene for the current epoch in which human activity impacts every ecosystem on the planet, and “Eco Art” is gaining currency as a term to describe art that furthers ecological sustainability or takes the form of environmental activism.