Southern California and the Santa Monica Mountains experience a climate similar to that of the Mediterranean basin. This means hot, dry summers, mild, wet winters, and large amounts of plant diversity. A major issue that can affect these regions is water availability and processing. To demonstrate this, hydraulic conductance (Kh) was measured as a function of leaf area (KS Leaf) and xylem size (KS Xylem). Two vascular plants were used for this study, Encelia californica and Venegasia carpesioides. This is because they are similar morphologically but are different genus and species. It was hypothesized that the larger plant (V. carpesioides) will have a larger hydraulic conductance (Kh), larger hydraulic conductance per leaf area (KS Leaf), as well as a larger hydraulic conductance per xylem area (KS Xylem) because of its larger need for water. Kh was found using a Sperry apparatus and the student t-test gave a P-value of 0.1517, which does not suggest a significant difference, KS Xylem (Kh/Axylem) using venier caliper and gave a P-value of 0.2867, which does not suggest a significant difference, and KLeaf (Kh/ Aleaf) using Leaf Area Index which gave a P-value of 0.0385, suggesting a significant difference in Leaf-specific hydraulic conductance (KS Leaf) between Encelia californica and Venegasia carpesioides. This shows that the hypothesis was only partially accepted.
Audin, Tony; Dudley, Andrew; and Gonzalez, Janel, "Differences in hydraulic conductance (Kh) as a function of leaf area (KS Leaf) and xylem size (KS Xylem) in Encelia californica and Venegasia carpesioides" (2010). Pepperdine University, Featured Research. Paper 16.