Lange O L, Zellner H, Gebel J, Schramel P, Köstner B, Czygan F-C
Institut für Botanik und Pharmazeutische Biologie der Universität Würzburg, Mittlerer Dallenbergwerg 64, D-8700, Würzburg, Federal Republic of Germany.
Gesellschaft für Strahlen- und Umweltforschung, Institut für Ökologische Chemie, D-8042, Neuherberg/München, Federal Republic of Germany.
Oecologia. 1987 Sep;73(3):351-357. doi: 10.1007/BF00385250.
Spruce (Picea abies) damage in the Fichtelgebirge (FRG) occurs as needle bleaching and a depression of CO assimilation. Such injury may primarily result from the direct, above-ground effects of air pollution or indirect, below-ground changes in mineral uptake.Typically, the new flush of spruce needles is green and exhibits high photosynthetic capacity. Mies and Zöttl concluded that the older foliage is damaged when nutrients are withdrawn to supply the current year's needles. By removing the terminal buds of single branches in the spring, we produced an experimental set of the previous year's needles with greater mineral reserves than the control needles. During the course of the growing period, the performance of the experimental needles, which lacked competition from the new flush, was compared to that of the control needles of the same age-class on intact branches with the new flush.Throughout the experiment, chloroplast pigments of a healthy control tree were not affected by the elimination of the new flush. However, the chlorophyll and carotenoid content as well as the photosynthetic capacity of the previous year's needles on those branches of a heavily damaged tree where the new flush had been eliminated increased substantially. This increase was associated with an increase in minerals, which seemed to be deficient in the control needles with the new flush. Thus, in contrast to needles of the same age-class on intact branches with undisturbed new growth in the same atmospheric environment, the experimental needles escaped bleaching and a decrease in photosynthesis. It would seem that the bleaching and the loss in photosynthetic capacity typical of trees damaged by forest decline indirectly result from nutrient deficiencies through soil environment changes and/or root damage than directly from atmospheric pollutants.
德国菲希特尔山脉的云杉（欧洲云杉）出现针叶褪色和二氧化碳同化作用降低的损害情况。这种损害可能主要源于空气污染的直接地上影响，或者是矿物质吸收方面间接的地下变化。通常，云杉新长出的针叶是绿色的，且具有很高的光合能力。米斯和措特尔得出结论，当养分被抽调以供应当年的针叶时，较老的叶子就会受到损害。通过在春季去除单个树枝的顶芽，我们培育出了一组试验用的前一年的针叶，其矿物质储备比对照针叶更多。在生长期间，将这些没有新叶竞争影响的试验针叶的表现，与同一树龄、带有新叶的完整树枝上的对照针叶进行比较。在整个实验过程中，健康对照树的叶绿体色素并未因去除新叶而受到影响。然而，在一棵严重受损的树上那些去除了新叶的树枝上，前一年针叶中的叶绿素和类胡萝卜素含量以及光合能力大幅增加。这种增加与矿物质含量的增加有关联，而对照针叶（带有新叶）似乎矿物质不足。因此，与在相同大气环境下新叶生长未受干扰的完整树枝上同龄针叶不同，试验针叶没有出现褪色现象，光合作用能力也没有下降。看起来，森林衰退受损树木典型的针叶褪色和光合能力丧失，与其说是直接源于大气污染物作用，不如说是通过土壤环境变化和/或根系损害导致养分缺乏而间接造成的。
