Nitrogen addition accelerates ecosystem phosphorus cycling at multiple scales in a temperate grassland of Northeast China

• DOI: 10.5194/egusphere-egu2020-1421
• Publication Date: 2020-03-09T13:33:12Z
• Authors: Haiying Cui; Manuel Delgado-Ba...; Wei Sun; Jian-Ying Ma; Wenzheng Song; Keying Wang; Xiaoli Ling
• Keywords: Nitrogen Cycle; Cycling; Nutrient cycle; Terrestrial ecosystem

<p>Plant phosphorus (P) resorption, mutualistic symbiosis with mycorrhizas, such as arbuscular mycorrhizal fungi (AMF) and soil organic P mineralization are crucial strategies for acquiring sufficient to meet plant nutrient demand. Which is the main strategy, however, responding elevated nitrogen (N) addition alleviate deficiency caused by N enrichment remains unclear in terrestrial ecosystems. We explored responses of foliar resorption dominate species (Leymus chinensis), microbial properties multi-level a temperate meadow steppe, Northeast China. found enhancements biomass, biomass C (MBC, MBN), alkaline phosphatase activities (ALP), phoD gene abundance (main coded ALP), while reductions pH, available P, AMF abundance, no significant content under simulative deposition. When rates exceeded threshold 10 g m<sup>-2</sup>yr<sup>-1</sup>, plants microbes had little additional enrichment. Notably, distinct effects on three acquisition strategies, that conspicuous increase efficiency, reduced dependence accelerated mineralization. A positive correlation between ALP activity, rate suggested increases its functional copies play roles Nitrogen aggravated production which further resorption. Due lack plasticity efficiency symbiosis, dominated increased Furthermore, activities, activation genes decrease pH were pathways accelerate consequently alleviated anthropogenic deposition, especially at conditions saturation. Our results provide strong evidences can cycling mobilize uptake leaf important better maintain sustainable ecosystem development more fertilized word.</p><p>Acknowledgments: This work was supported National Key Research Development Program China (2016YFC0500602), Natural Science Foundation (31570470, 31870456), Fundamental Funds Central Universities (2412018ZD010), Introducing Talents Discipline (B16011). H.C. acknowledges support from Chinese Scholarship Council (CSC).</p>