World Dynamics

accumulate action actual agriculture appear assumed assumptions average become behavior better billion birth rate capital investment Capital-investment cause Chapter consequences continue created crowding curve death rate decline defined depends described developed discard discussed dynamic effect environment equation equilibrium examine existing expect factors falling Figure food production food ratio forces fraction future gives grow growth higher improve increase indicates industrialization influence INITIAL land less limit LOGICAL FUNCTION loop lower material standard means mental mode MULTIPLIER DIMENSIONLESS natural resources NATURAL-RESOURCE needed normal NREM occurs person policies pollution crisis pollution ratio POLR population possible pressures probably processes rate normal RATIO DIMENSIONLESS reaches reduced relationship remaining represents result rise sector shortage shown shows social systems space standard of living stop structure suppressed SWITCH TABLE taken tion understand UNITS usage variable world system