The natural environment has complicatedly changed due to the short-term changes by human activities added to the long-term basic changes in the nature.
 The global environmental problems presently intimidating our life and existence indicate the change in natural environment toward an environment undesirable for our healthy and wealthy life resulting from destruction of natural ecosystem by human activities.
 In order to preserve the natural environment and to create a natural environment desirable for us, we need to understand precisely the changes of natural environment through the earth history, to evaluate adequately the effect of the changes on our life, and to predict correctly the changes for the future.
 The program of Natural Environmental Changes focuses on the researches for the changes in geomorphic environment, climatic environment, water environment and bio-environment mainly on the basis of geological, geomorphological and archaeological data, and intends to clarify the human-nature relationships. It tries to establish the methods and techniques for rehabilitation and preservation of natural environment, and for development of a new socio-natural environment.