Previous research has shown that across the major groups of plants there is a strong positive relationship between stomatal conductance and hydraulic conductance (as shown in the adjacent figure). Using Fick’s law and Darcy’s law discuss why we generally observe a positive relationship between stomatal conductance and hydraulic conductance across plant species? In other words, species with a low hydraulic conductance are not able to achieve a high stomatal conductance and therefore a high transpiration rate, Why? [Note: all the stomatal conductance values in the adjacent figure were measured at the same (wi - wa) ] 700 600 3500 2 400 5300 200 O 100 10 20 30 40 Leaf hydraulic conductance (mol m-2 s-1 MPa-1) Fig. 2 A highly significant linear correlation (r2 0.87) between mean leaf hydraulic conductance (so; n- 9) and stomatal conductance (±SD; n = 9) in a sample of tropical (O) and temperate (A) angiosperms, tropical ferns (), and temperate conifers (A). 700 600 3500 2 400 5300 200 O 100 10 20 30 40 Leaf hydraulic conductance (mol m-2 s-1 MPa-1) Fig. 2 A highly significant linear correlation (r2 0.87) between mean leaf hydraulic conductance (so; n- 9) and stomatal conductance (±SD; n = 9) in a sample of tropical (O) and temperate (A) angiosperms, tropical ferns (), and temperate conifers (A).