Do palm water use characteristics explain the spatial distribution of palms in the Central Amazon

摘要: We studied plant water use characteristics of the tree Theobroma grandiflorum (Cupuacu, (Willd. ex Spreng.) Schum., Malvaceae) and palm Euterpe precatoria (Acai, Mart., Arecaceae) both native to Amazon commonly occurring in region. The species is mainly terra firme forest whereas restricted extreme habitats stream valleys. This study was conducted a small fruit plantation close city Manaus, Central Amazon, Brazil. main objective this compare relation structural traits. Three representative individuals each were equipped with Granier-type thermal dissipation probes measure sap flux density. Water scaled independent size conductive xylem area (r2=0.85). Furthermore, we found clear species-specific scaling plant-size. Overall, palms had 3.5-fold higher consumption compared trees similar stem diameter and/or height. Palms transpired mean 1.67 mm m-2 per unit crown projection day, only 0.30 resulting 5.6 times lower transpiration rate. assume that especially unbalanced height/water ratio might be limiting height growth due increasing hydraulic limitations. Hence, are availability usually do not co-occur more efficient taller broad leaved forest.