Impacts of N/P inputs on organic P dynamics and P status in soils and plants along a nutrient gradient

N/P 输入对沿养分梯度的土壤和植物有机磷动态和磷状态的影响

• 批准号: 241216797
• 负责人: Professorin Dr. Yvonne Oelmann
• 金额: --
• 依托单位: Institut für Pflanzenbauwissenschaften
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/241216797?language=en
• 关键词: Impacts; inputs; organic; dynamics; status

Atmospheric nitrogen (N) deposition has been shown to affect N cycling in forests with feedbacks on the phosphorus (P) cycle. Therefore, the main objective of the 2nd phase of the SPP 1685 priority program is to investigate the importance of soil organic matter turnover on P cycling under environmental change. This will be tested in a common field experiment installed in Lüss and Bad Brückenau studying the effect of N, P and N+P additions on N and P dynamics and forest nutrition. Major effects are expected in Lüss, the P-limited ecosystem, which would eventually shift from a recycling to an acquiring strategy.The objectives of our joint proposal (Group of Plant Nutrition, ETH Zurich; Group of Geoecology, University of Tübingen; Group of Environmental Sensing and Monitoring, FZ Jülich) are to determine which and to which extent soil biological processes in the forest ecosystem are affected by mineral N and P additions and how this further translates into plant nutrition over the three years of the second phase of the SPP 1685. We plan to extend the set of field sites because of the unique opportunity to study the fate of fertilizer-P by radioactive isotopes (P-32, P-33) under outdoor conditions in a forest at the FZ Jülich (intermediate in terms of soil P fractions as compared to Lüss and Bad Brückenau). Our hypotheses are that after mineral fertiliser additions, the distribution of inorganic and organic P forms in soils will change, more in Lüss than in Jülich and Bad Brückenau. The mineralogy and initial P status of the soils will also be determinant factors for the changes. As a result, the source for plant P (and N) nutrition will differ between Lüss, Jülich, and Bad Brückenau. Processes in soil and fluxes in soil and between plants and soil will also be affected in the short term (3 years of the project), most likely because of an increased organic matter turnover. We will use microbiological tools and P-31 NMR analysis together with stable and radioactive isotope techniques. Using these complementary tools we will be able to quantify soil and plant P pools, characterize organic P forms, assess soil microbial community structure harbouring phosphatase genes, quantify fluxes of P between pools in soils and plants, and identify the contribution of different sources for plant nutrition of exemplary forest ecosystems subject to N and P additions.

大气氮(N)沉积已被证明通过对P循环的反馈来影响森林中的N循环。因此，SPP1685优先计划第二阶段的主要目标是研究环境变化下土壤有机质周转对P循环的重要性。这将在Lüss和巴德布鲁克瑙设置的一个普通田间试验中进行验证，研究N、P和N+P添加对N、P动态和森林营养的影响。我们联合提案(苏黎世理工大学植物营养小组；图宾根大学地球生态小组；FZ Jülich环境传感和监测小组)的目标是确定森林生态系统中的土壤生物过程受到矿物质N和P添加的影响，以及这种影响如何在SPP1685第二阶段的三年内进一步转化为植物营养。我们计划扩大田间地点，因为这是一个独特的机会，可以在室外条件下通过放射性同位素(P-32，P-33)在FZ Jülich的森林中研究化肥-P的去向(与Lüss和巴德·布吕克瑙相比，土壤P组分处于中等水平)。我们的假设是，在添加矿物质肥料后，土壤中无机和有机磷形态的分布将发生变化，在Lüss比在Jülich和Bad Bruück enau更大。土壤的矿物学和初始磷状况也将是决定变化的因素。因此，植物P(和N)营养的来源将在L、朱利希和巴特布鲁克瑙之间有所不同。土壤中的过程和土壤中的通量以及植物和土壤之间的通量在短期内(项目的3年)也将受到影响，很可能是因为有机物质周转增加。我们将使用微生物工具和P-31核磁共振分析以及稳定和放射性同位素技术。使用这些辅助工具，我们将能够量化土壤和植物的磷库，表征有机磷的形态，评估含有磷酸酶基因的土壤微生物群落结构，量化土壤和植物的磷库之间的磷通量，并确定不同来源对N和P添加的典型森林生态系统植物营养的贡献。