Murray M. B., Smith R. I., Leith I. D., Fowler D., Lee H. S., Friend A. D., Jarvis P. G.
Institute of Terrestrial Ecology, Bush Estate, Penicuik EH26 0QB, Midlothian, U.K.
Tree Physiol. 1994 Jul-Sep;14(7_9):691-706. doi: 10.1093/treephys/14.7-8-9.691.
Effects of elevated CO(2), clone and plant nutrition on bud dormancy of Sitka spruce (Picea sitchensis (Bong.) Carr.) were examined. Sitka spruce seedlings were fumigated with ambient or elevated (ambient + 350 micro mol mol(-1)) concentrations of CO(2) in open-top chambers for three growing seasons. In 1991 and 1992, elevated CO(2) delayed bud burst in the spring and advanced bud set in the autumn. The effect of the open-top chamber on the thermal requirement for bud burst was greater than the effect of elevated CO(2) (50 and 30 day degrees (D(d)), respectively). In a second study, four clones of Sitka spruce taken from two provenances, at 43 and 54 degrees N, were fumigated with ambient or elevated CO(2). There was a large natural variation in the timing of bud burst and bud set among the clones. Elevated CO(2) had no effect on bud dormancy of the Skidegate a clone, but it reduced the growing season of the North Bend b clone by 20 days. In a third study, Sitka spruce seedlings growing in ambient or elevated CO(2), were supplied with one of three nutrient regimes, low (0.1 x potential), medium (0.5 x potential) or high (2.0 x potential), using a method and solution based on the Ingestad technique. Elevated CO(2) did not affect bud dormancy in the high-nutrient treatment, but it reduced the growing season of plants in the low-nutrient treatment by 22 days. Increasing plant nutrient supply lengthened the growing season, plants flushed earlier in the spring and set bud later in the autumn. The effects of elevated CO(2) plus a 0, 2 or 4 degrees C climatic warming on the timing of bud burst and the subsequent risk of frost damage were assessed using a simulation model and meteorological data from three sites, Edinburgh, Braemar and Masset. The model predicted that (i) doubling the CO(2) concentration in the absence of climatic warming, will delay the onset of bud burst at all three sites, (ii) climatic warming in ambient CO(2) will hasten bud burst and (iii) climatic warming in elevated CO(2) will hasten bud burst at Edinburgh and Braemar but to a lesser extent than climatic warming alone. At Masset, a 4 degrees C warming was required to advance the date of bud burst of seedlings in the elevated CO(2) treatment. At all three sites, elevated CO(2) and climatic warming increased the mean daily temperature on the date of bud burst, thus reducing the risk of subsequent frost damage.
研究了二氧化碳浓度升高、克隆以及植物营养对西加云杉（Picea sitchensis (Bong.) Carr.）芽休眠的影响。在开放式气室中，用环境浓度或升高浓度（环境浓度 + 350微摩尔/摩尔）的二氧化碳对西加云杉幼苗进行熏蒸处理，持续三个生长季。在1991年和1992年，二氧化碳浓度升高使春季芽萌发延迟，秋季芽形成提前。开放式气室对芽萌发所需热量的影响大于二氧化碳浓度升高的影响（分别为50和30日度（D(d)））。在第二项研究中，从北纬43度和54度的两个种源采集的四个西加云杉克隆体，用环境浓度或升高浓度的二氧化碳进行熏蒸处理。各克隆体之间芽萌发和芽形成的时间存在很大的自然差异。二氧化碳浓度升高对斯基德盖特a克隆体的芽休眠没有影响，但使北本德b克隆体的生长季缩短了20天。在第三项研究中，用基于英格斯塔德技术的方法和溶液，为生长在环境浓度或升高浓度二氧化碳中的西加云杉幼苗提供三种营养方案之一，即低（0.1×潜在水平）、中（0.5×潜在水平）或高（2.0×潜在水平）。在高营养处理中，二氧化碳浓度升高不影响芽休眠，但在低营养处理中使植物生长季缩短了22天。增加植物养分供应延长了生长季，植物在春季更早萌发，秋季更晚形成芽。使用模拟模型和来自爱丁堡、布雷马和马塞特三个地点的气象数据，评估了二氧化碳浓度升高加上0℃、2℃或4℃的气候变暖对芽萌发时间以及随后霜冻危害风险的影响。该模型预测：（i）在没有气候变暖情况下，将二氧化碳浓度加倍，会使所有三个地点的芽萌发开始时间延迟；（ii）环境浓度二氧化碳下的气候变暖会加速芽萌发；（iii）升高浓度二氧化碳下的气候变暖会使爱丁堡和布雷马两地的芽萌发加速，但程度小于单独的气候变暖。在马塞特，需要4℃的升温才能使升高浓度二氧化碳处理下的幼苗芽萌发日期提前。在所有三个地点，二氧化碳浓度升高和气候变暖都增加了芽萌发当天的日均温度，从而降低了随后遭受霜冻危害的风险。
