... foliage nitrogen concentration and leaf area index: a modelling analysisDavid WHITEHEAD a *, Adrian S. WALCROFTb a Landcare Research, PO Box 69, Lincoln 8152, New Zealandb Landcare Research, ... (f.) Poole and Pinuscontorta Douglas ex Loudon spp. contorta at alpine and subalpinealtitudes, in: Waring R.H. (Ed.), Carbon Uptake and Allocation in Subalpine Ecosystems as a Key to Management, ... results of a simulationwhere leaf area index, L, is increased by50% and foliage nitrogen concentration, N a , is increased by 20%. Carbon uptake, leaf area and nitrogen 527photosynthesis in some...