Radiation interception and productivity of willow.
Abstract
Stands of Salix viminalis growing near Edinburgh, UK, were studied in 1984 (1st yr growth from 2-yr coppice stumps) and 1985 (1st yr growth from cuttings). Accumulated DM was linearly related to accumulated intercepted radiation until heavy leaf fall, with a slope of 0.99 g/MJ in 1984 (11 t/ha annually) and 1.38 g/MJ in 1984 (14 t/ha annually); greater efficiency in 1985 is attributed to better water and nutrient supplies and lower rates of incoming radiation. Light interception (and hence DM production) was relatively insensitive to increases in LAI above 4.5, or delayed leaf fall, but was increased greatly by earlier canopy development.