Abstract

An experiment with the enrichment of acid organic-rich mountain-meadow soils (Umbric Leptosols) of alpine ecosystems with mineral nutrients has demonstrated that the contents of organic carbon, total nitrogen, and labile organic compounds are stable and tolerant towards long-term (20 years) application of mineral fertilizers. Only the following direct effects are well pronounced: an increase in the content of inorganic nitrogen and phosphorus after the application of corresponding fertilizers, as well as a rise in pH as a result of liming. Plants are more sensitive indicators of changes in the conditions of nitrogen nutrition. They are characterized by active absorption of additional nitrogen, and the isotopic composition of nitrogen in them becomes heavier. The degree of these effects depends on the initial nitrogen availability. In addition to these direct effects, changes in the nitrogen status of plants also reflect changes in the transformation of nitrogen-containing compounds in soil and in the nitrogen nutrition of plants taking place due to an increased availability of phosphorus and lower acidity under the most phosphorus-depleted and most acid conditions, respectively. These impacts lead to the mobilization of soil organic nitrogen and are likely to reduce the role of mycorrhiza in plant nitrogen nutrition. As a result, a heavier isotopic composition of nitrogen is formed in some plant species.

中文翻译：

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生物量可利用量长期增加下的西北高加索高山生态系统植物的土壤和氮营养

摘要

一项利用矿物质营养素丰富高山生态系统中富含酸性有机物的高山草甸土壤（Umbric Leptosols）的实验表明，有机碳，总氮和不稳定的有机化合物的含量稳定且可长期耐受（20年）的矿物肥料的应用。只有以下直接作用才很明显：施用相应肥料后无机氮和磷的含量增加，以及由于石灰添加而导致pH值升高。植物是氮营养状况变化的更敏感指标。它们的特征是主动吸收额外的氮，并且其中的氮同位素组成变得更重。这些影响的程度取决于初始氮的可用性。除了这些直接作用外，由于磷的有效性增加，而大多数磷在较低的酸度下，植物中氮含量的变化也反映了土壤中含氮化合物的转化以及植物中氮营养的变化。 -贫化和大多数酸性条件。这些影响导致土壤有机氮的动员，并可能减少菌根在植物氮营养中的作用。结果，在一些植物物种中形成了较重的氮同位素组成。植物中氮素状态的变化也反映了土壤中含氮化合物的转化以及植物中氮素营养的变化，这归因于在最贫磷和最酸的条件下磷的有效性增加和酸度降低，分别。这些影响导致土壤有机氮的动员，并可能减少菌根在植物氮营养中的作用。结果，在一些植物物种中形成了较重的氮同位素组成。植物中氮素状态的变化也反映了土壤中含氮化合物的转化以及植物中氮素营养的变化，这归因于在最贫磷和最酸的条件下磷的有效性增加和酸度降低，分别。这些影响导致土壤有机氮的动员，并可能减少菌根在植物氮营养中的作用。结果，在一些植物物种中形成了较重的氮同位素组成。