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对瑞典南部 2 3对相邻的桦树和欧洲云杉林分的地表植被和土壤特征进行了研究。桦树和欧洲云杉林分曲芒发草( Deschampsia flexuosa L.)和苔藓植物的频度几乎没有区别 ,但桦树林分越桔 ( Vaccinium myrtillus L.)和黑果越桔 ( Vac-cinium vitis-idaea L.)的频度远大于欧洲云杉林分的频度。欧洲云杉林分各层土壤 (腐殖质层、0～ 1 0 cm矿物质土壤层和1 1～ 30 cm矿物质土壤层 )的酸度稍大于桦树林分各层土壤的酸度。欧洲云杉林分土壤可交换性 K、Ca和 Mg离子的含量稍大于桦树林分土壤的含量 ,但差别不明显 ,只有可交换性 Na离子的含量在欧洲云杉林分土壤中明显偏高。由于现在硫沉降明显降低 ,相对于桦树冠层而言欧洲云杉冠层较高的阳离子干沉降在一定程度上可能中和土壤酸化对瑞典南部欧洲云杉林的影响
The surface vegetation and soil characteristics of 23 adjacent birch and European spruce stands in southern Sweden were studied. There was almost no difference in the frequency of birch and European spruce trees between Deschampsia flexuosa L. and bryophytes, but Vaccinium myrtillus L. and Vac-cinium vitis -idaea L.) is much more frequent than the European spruce stand frequency. The acidity of soil (humus layer, 0 ~ 10 cm mineral soil layer and 11 ~ 30 cm mineral soil layer) in each layer of Picea schrenkiana forest was slightly higher than that of the soil layer in the birch stand. The content of exchangeable K, Ca and Mg ions in the spruce stand was slightly larger than that in the birch stand, but the difference was not obvious. Only the content of exchangeable Na ions was obviously higher in the spruce stand soil . Due to the marked reduction in sulfur present, the higher dry deposition of cationic spruce canopy relative to birch canopy, to a certain extent, may neutralize the effect of soil acidification on the spruce forest in southern Sweden