Being the product of the same environment, soil and vegetation are mutually associated with each other, but the relationships between edaphic properties and vegetation characteristics are still far from clear. Accordingly, the specific aim of this study is to identify relationships between forest site types/forest types and the fertility of soil organic horizons in northwestern Russia. The relationships were assessed at the level of three large forest regions, the northern and middle taiga of the Republic of Karelia, and the Karelian Isthmus (Leningrad region), based on 37 spruce, 66 pine, and 16 birch plots which were integrated with the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). Soil forming rock and land-use history partly explain the differences in the fertility of soil organic horizons between the forest ecosystems in northwestern Russia. Climatic factors are closely correlated with plant species richness, density and the fertility of soil organic horizons. Nutrient content in the organic horizons increased from poor to rich site types identified according to composition of understory vegetation and the occurrence of certain indicator species, i.e. Cajander’s forest site types. The most informative parameters in explaining differences between Cajander’s types were nitrogen, carbon to nitrogen ratio, exchangeable calcium, magnesium, potassium, and base saturation. Extractable phosphorus, carbon to nitrogen ratio, exchangeable calcium, magnesium, aluminum and base saturation were the most informative parameters in explaining differences between forest types identified within the Cajander types in accordance with the tree species composition, i.e. Sukachev’s forest types. The organic horizons of spruce and birch-dominated forests contained significantly more nutrients, compared to those dominated by pine. These differences were explained by differences in litter quality, and the crown shape and density of tree species, which affect the intensity of nutrient leaching. The study presents new findings regarding the relationships between forest sites/types and the fertility of soil organic horizons in northwestern Russia. Differences in organic horizon’s fertility between the taiga subzones are explained by differences in the soil forming rock, climatic conditions, land-use history and shares of forest site types/forest types.

中文翻译：

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俄罗斯西北部森林植被与土壤有机层肥力之间的关联

土壤和植被是同一环境下的产物，彼此相互联系，但土壤养护性质和植被特征之间的关系还很不清楚。因此，本研究的具体目的是确定俄罗斯西北部森林林地类型/森林类型与土​​壤有机层肥力之间的关系。根据37个云杉，66个松树和16个桦木样地与三个大型森林区域，卡累利阿共和国的北部和中部针叶林和卡累利阿地峡（列宁格勒地区）的水平对这种关系进行了评估。评估和监测森林空气污染影响国际合作方案（ICP森林）。土壤形成岩石和土地利用的历史部分解释了俄罗斯西北部森林生态系统之间土壤有机层肥力的差异。气候因素与植物物种丰富度，密度和土壤有机层的肥力密切相关。根据下层植被的组成和某些指示物种的出现，即卡赞德林地的类型，有机层中的营养含量从劣地类型增加到富地类型。解释Cajander类型之间差异的最有用的参数是氮，碳氮比，可交换的钙，镁，钾和碱饱和度。可提取的磷，碳氮比，可交换的钙，镁，铝和基础饱和度是最有信息的参数，可用来解释根据树种组成在苏珊奇夫（Sukachev）的森林类型中在Cajander类型中确定的森林类型之间的差异。与以松树为主的森林相比，云杉和桦树为主的森林的有机地带含有更多的养分。这些差异可以通过凋落物质量，树冠形状和密度的差异来解释，这些差异会影响养分的淋失强度。该研究提出了有关俄罗斯西北部森林地点/类型与土壤有机层肥力之间关系的新发现。针叶林次区域之间有机层肥力的差异可以通过形成岩石的土壤，气候条件，