Intraspecific variation of leaf traits in several deciduous species in relation to length of growing season

Effects of growing season length on leaf traits were studied in three deciduous species found along an alpine snowmelt gradient (snow-free period ranging from 69 to 117 days), and in four deciduous species found along an altitudinal gradient (ranging from 140 m to 1900 m) in northern Japan. Along these gradients, leaf life-span generally decreased while specific leaf area (SLA) and nitrogen concentration (leaf N) increased with a shorter growing season. In each species, there was a negative correlation between leaf life-span and SLA, and between leaf life-span and leaf N, respectively. A positive correlation was found between SLA and leaf N. Production of high nitrogen leaves which had a lower initial carbon investment (leaf construction cost) was considered to be a response to maintain the carbon balance under the condition of a short growing season.