Can fog contribute to the nutrition of Chamaecyparis obtusa var. formosana? Uptake of a fog solute tracer into foliage and transport to roots.
Yellow cypress (Chamaecyparis obtusa (Siebold & Zucc.) Endl. var. formosana (Hayata) Rehder) is the predominant tree species of Taiwan's nutrient-poor, mountain fog forests. Little is known about the potential contribution of solute uptake from fog to the overall nutrition of these trees. Shoots of yellow cypress seedlings were misted with artificial fog containing the tracer rubidium (Rb) in laboratory and field experiments to determine if there is solute uptake from the fog. After misting shoots for six weeks, substantial amounts of tracer were detected in unexposed roots by inductively coupled plasma mass spectroscopy bulk analysis. Possible routes of entry were examined by element imaging with energy dispersive X-ray analysis. Direct uptake of the tracer into leaves across the cuticle and epidermis was small, excluding this as the major uptake path. Accumulations of Rb were found on leaf surfaces along the edges of the leaves. The almost daily changes in fog coverage and air humidity may enhance the accumulation of fog solutes at leaf edges. Accumulation of Rb was also found in narrow clefts between opposite leaves and between the outermost and underlying alternating stacked leaves. The clefts provide a direct passage from the leaf surface to the space beneath the imbricate leaves and the underlying alternate leaves, possibly facilitating solute uptake from fog, which in turn may contribute to the nutrition of yellow cypress.
Lai
I-Ling
IL
Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 106, Taiwan.
Schroeder
Walter H
WH
Wu
Jiunn-Tzong
JT
Kuo-Huang
Ling-Long
LL
Mohl
Carola
C
Chou
Chang-Hung
CH
D029780:Chamaecyparis / Q000378:metabolism* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D018515:Plant Leaves / Q000378:metabolism* / Q000648:ultrastructure; D018517:Plant Roots / Q000378:metabolism* / Q000648:ultrastructure; D012413:Rubidium / Q000378:metabolism; D036226:Seedlings / Q000378:metabolism / Q000648:ultrastructure
D012413:Rubidium