Abstract

M orphological and anatomical features of plant leaves are commonly associated with metabolic type (e.g., Kranz anatomy of C4 species), amount of sun exposure (e.g., sun and shade leaves), or water stress (e.g., xeromorphism). However, although the primary function of the leaf is to absorb and process sunlight and carbon dioxide for photosynthesis, few structural features of leaves have been related mechanistically to these tasks. For example, it has been known for over a century that the internal anatomy of leaves is characterized by different cell layers (e.g., the palisade and spongy mesophyll) and that stomatal pores can be located on one or both sides of a leaf. Yet, only recently has any functional relationship between leaf form and photosynthetic performance been suggested. A variety of ecological studies have correlated numerous leaf structural parameters with photosynthetic performance (e.g., Abrams and Kubiske 1990, 1994, Hinckley et al. 1989,