Brown Kevin, Higginbotham K. O.
Department of Forest Science, University of Alberta, Edmonton, Alberta, Canada, T6G 2H1.
Tree Physiol. 1986 Dec;2(1_2_3):223-232. doi: 10.1093/treephys/2.1-2-3.223.
The effects of two levels of atmospheric carbon dioxide (350 microl l(-1), 750 microl l(-1)) and three levels of nitrogen (15.5 mM, 1.55 mM, 0.155 mM N) on biomass accumulation and partitioning were examined in aspen (Populus tremuloides Michx.) and white spruce (Picea glauca (Moench) Voss) seedlings grown in controlled environment rooms for 100 days after germination. Nitrogen supply had pronounced effects on biomass accumulation, height, and leaf area of both species. Root weight ratio (RWR) of white spruce was significantly increased at the lowest level of nitrogen, whereas RWR of aspen did not change much with increasing levels of nitrogen. Carbon dioxide enrichment significantly increased (1) the leaf and total biomass of spruce seedlings grown in the high-N regime, (2) the RWR of seedlings in the medium-N regime, and (3) the root biomass of seedlings in the low-N regime after 100 days. Carbon dioxide enrichment of aspen temporarily increased biomass and height in all three nitrogen regimes. Root, stem, and leaf mass, height, and leaf area of aspen were increased only at the 30-day harvest in the high-N treatment and at 50 and 60 days in the low-N treatment. Height, stem biomass, and leaf biomass of aspen seedlings were significantly increased by CO(2) enrichment after 40 days in the medium-N treatment. These effects did not persist, possibly because of the onset of mineral nutrient supply limitations with increasing plant size.
在发芽后于可控环境室中培养100天的山杨（Populus tremuloides Michx.）和白云杉（Picea glauca (Moench) Voss）幼苗上，研究了两种大气二氧化碳水平（350微升升⁻¹、750微升升⁻¹）和三种氮水平（15.5毫摩尔、1.55毫摩尔、0.155毫摩尔氮）对生物量积累和分配的影响。氮供应对两个物种的生物量积累、高度和叶面积均有显著影响。白云杉的根重比（RWR）在最低氮水平时显著增加，而山杨的RWR随氮水平增加变化不大。二氧化碳浓度升高显著增加了：（1）高氮处理下生长的云杉幼苗的叶和总生物量；（2）中氮处理下幼苗的根重比；（3）100天后低氮处理下幼苗的根生物量。山杨在所有三种氮处理下，二氧化碳浓度升高均暂时增加了生物量和高度。山杨的根、茎和叶质量、高度以及叶面积仅在高氮处理的30天收获时、低氮处理的50天和60天时有所增加。在中氮处理40天后，二氧化碳浓度升高显著增加了山杨幼苗的高度、茎生物量和叶生物量。这些影响并未持续，可能是由于随着植株大小增加矿物质养分供应开始受限。
