Braun Sabine, Flückiger Walter
Institute for Applied Plant Biology, Sandgrubenstrasse 25, 4124 Schönenbuch, Switzerland.
New Phytol. 1995 Jan;129(1):33-44. doi: 10.1111/j.1469-8137.1995.tb03007.x.
The effect of unfiltered versus filtered air was tested on tree seedlings at different sites with prevailing ozone pollution, at different altitudes. Growth and biomass data from different experiments were evaluated in relation to ozone dose above 40 nl l during the exposure time. In beech (Fagtis sylvatica L.), biomass was significantly correlated with ozone dose whereas shoot length was not. There was no change in shoot/root ratio but there were more significant reductions in fine root biomass than in shoot biomass. The effect of ozone was cumulative within the duration of the experiments, i.e. from a few months to three years. A cumulative dose of 7 μl 1 h > 40 nl l Per growing season, calculated for 24 h day , corresponded to a 10% biomass reduction within three years. Seedlings grown in unfiltered air also exhibited much more severe symptoms of frost injury following a cold winter with rapid temperature change. Laboratory experiments suggest that winter desiccation may have played a more important role than low temperatures, but that medium frost temperatures may cause more latent injuries in seedlings exposed to ambient air. Water loss of detached leaves from unfiltered air was significantly higher later m the season. Both increased chlorosis and premature leaf fall were observed in the beech seedlings grown in unfiltered air, but in different years. The biomass of spruce [Picea abies (L.) Karst.] showed a tendency towards a reduction, but this was not significant within the dose range tested. Three years of fumigation, however, caused increased chlorosis also in the spruce seedlings. Tests with low temperatures suggest that the vitality of the spruce seedlings during winter may also be impaired by the ambient air pollution.
在不同海拔、存在臭氧污染的不同地点，对树木幼苗进行了未过滤空气与过滤空气效果的测试。将不同实验中的生长和生物量数据与暴露期间高于40 nl l的臭氧剂量相关联进行评估。在山毛榉（Fagtis sylvatica L.）中，生物量与臭氧剂量显著相关，而苗高则不然。茎根比没有变化，但细根生物量的显著减少比地上生物量更多。在实验持续期间，即从几个月到三年，臭氧的影响是累积的。每个生长季节7 μl 1 h > 40 nl l的累积剂量（按每天24小时计算）相当于三年内生物量减少10%。在未过滤空气中生长的幼苗在经历了温度快速变化的寒冷冬季后，还表现出更严重的冻害症状。实验室实验表明，冬季干燥可能比低温起了更重要的作用，但中等霜冻温度可能会在暴露于环境空气的幼苗中造成更多潜在伤害。在季节后期，未过滤空气中离体叶片的水分流失显著更高。在未过滤空气中生长的山毛榉幼苗中，观察到了黄化增加和叶片过早脱落，但发生在不同年份。云杉[Picea abies (L.) Karst.]的生物量有减少的趋势，但在测试的剂量范围内不显著。然而，三年的熏蒸也导致云杉幼苗黄化增加。低温测试表明，环境空气污染也可能损害云杉幼苗冬季的活力。
