"It became clear by the late 1960's that the major issue confronting us was planetary ecological change," he said.

Iwokrama evaluates the social, economic and ecological changes that occur as a result of business development.

Perhaps ecological changes as well - behavioral changes, although I can't he sure of that.

The climatic and ecological changes preceded them, according to this analysis.

Long-term ecological changes in the densely populated rural landscapes of China.

Possible explanations for this fall into three broad categories: environmental, developmental, and ecological changes.

The project allows the garden to tell a story of ecological change and the importance of restoration.

These ecological changes in turn impact many recreational and commercial activities dependent on aquatic ecosystems.

Various environmental and ecological changes could also influence the emergence of viruses, the doctors said.

But the crossover caused great ecological change and half the world was submerged underwater.