Analysis with 1987 data excluded confirmed a strong trend of increasing V M with E, as did simpler models where we used first- or second-order functions of environmental quality (Models II and III; Figure 1 ).
1
—
—
Analysis with 1987 data excluded confirmed a strong trend of increasing V M with E, as did simpler models where we used first- or second-order functions of environmental quality (Models II and III; Figure 1 ).