Nitrogen loading enhances phosphorus limitation in terrestrial ecosystems with implications for soil carbon cycling

作者：Min Luo, Daryl Moorhead, Raúl Ochoa‐Hueso, Carsten W. Mueller, Samantha C. Ying, Ji Chen · 发表于：Functional Ecology · 年份：2022 · DOI：10.1111/1365-2435.14178 · 被引用次数：203 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Water Nutrient Dynamics、Peatlands and Wetlands Ecology

Abstract Increased human‐derived nitrogen (N) loading in terrestrial ecosystems has caused widespread ecosystem‐level phosphorus (P) limitation. In response, plants and soil micro‐organisms adopt a series of P‐acquisition strategies to offset N loading‐induced P limitation. Many of these strategies impose costs on carbon (C) allocation by plants and soil micro‐organisms; however, it remains unclear how P‐acquisition strategies affect soil C cycling. Herein, we review the literature on the effects of N loading on P limitation and outline a conceptual overview of how plant and microbial P‐acquisition strategies may affect soil organic carbon (SOC) stabilization and decomposition in terrestrial ecosystems. Excessive input of N significantly enhances plant biomass production, soil acidification, and produces plant litterfall with high N/P ratios, which can aggravate ecosystem‐level P limitation. Long‐term N loading can cause plants and soil micro‐organisms to alter their functional traits to increase P acquisition. Plants can release carboxylate exudates and phosphatases, modify root morphological traits, facilitate the formation of symbiotic associations with mycorrhizal fungi and stimulate the abundance of P‐mineralizing and P‐solubilizing micro‐organisms. Releasing carboxylate exudates and phosphatases could accelerate SOC decomposition, whereas changing symbiotic associations and root morphological traits (e.g. an increase in fine root length) may contribute to higher SOC sta...