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在557块针叶林分中进行调查,以图了解欧洲越桔(Vaccinium myrtillus)、越桔(V.vitis-idaea)和曲芒发草(Deschampsia flexuosa)与氮沉积率的相互联系。欧洲越桔在高氮地区比在低氮地区发生频度、丰富度都较少并且易感染叶部病原(Valdensia heterodoxa),越桔的发生与氮沉积的增加呈明显的负相关,曲芒发草却没有这种趋势。在高氮沉积地区,欧洲越桔在优势种为欧洲赤松的林分中比在挪威云杉为优势种的林分中更为最普遍。在氮沉积较低水平的地区不是这种情形。调查的情况与增施氮素实验的结果一致,氮沉积对植被显示了巨大的效应。数据表明即使是较低的氮沉积也可能减少针叶林分林下植被最优势种的丰富度。
A survey was conducted among 557 coniferous forest plots to understand the interdependence of nitrogen deposition rates on Vaccinium myrtillus, V. vitis-idaea and Deschampsia flexuosa. European bilberry occurred more frequently in areas with high nitrogen than in areas with lower nitrogen, with less abundance and susceptible to leaf-borne pathogen (Valdensia heterodoxa). The occurrence of bilberry was negatively correlated with the increase of nitrogen deposition. Grass has no such trend. In areas of high nitrogen deposition, bilberry was more prevalent among the dominant species of Pinus sylvestris than the dominant species of Norway spruce. This is not the case in areas with lower levels of nitrogen deposition. The investigation is consistent with the results of the experiment of nitrogen addition, which shows a great effect on vegetation. The data indicate that even low nitrogen depositions may reduce the abundance of the most dominant species of understory vegetation in the coniferous forest.