In actuality, Christian theologians contributed significantly to early ecological thought, much like they participated in every facet of culture. They recognized that human activity changes the natural environment and therefore biological processes. What theology offers quite successfully is what has been missing in the more money-oriented flavor of modern environmentalism - a positive approach on a cosmic scale.
Writing in Open Theology, Dr. Panu Pihkala from the University of Helsinki details Christian environmentalism and the Christians who partook in early green politics. It is believed that ecotheology only surfaced in the late 1960s - hippies who embraced nature and Jesus - but much earlier texts show that significant elements were converting to the service of the earth community well before that.
Prior to the 1960s, when modern environmentalists took hold of the movement, there was a great deal of cooperation with religion and disagreements were scarce, because it was not about government regulation and money and population control - the constructive resources of Christian theology and ethics helped guide movement toward preserving nature.
This kind of theological archeology, bringing ecotheological reflection, could take environmentalist culture back from malevolent groups like Greenpeace and SourceWatch, and put it squarely in mainstream positive approaches again.