Text of the President's Third Annual Environmental Message to Congress is repeoduced. New policies and proposals to improve the Nation's environment are outlined together with an urging on the proposals given in previous years. The year 1972 should be a year of action, to move from intention to accomplishment. The message points up the importance of decisive action by the Congress to adopt and implement measures that would strengthen present programs, control emerging problems and promote overall environmental quality. New areas of concern focus on: (1) tightening pollution control, (2) making technology an environmental ally, (3) improving land use, (4) protecting our natural heritage, (5) expanding international cooperation on the environment, (6) protecting children from lead-based paint, and (7) enlisting the young. (BL)