Increased human\uffe2\uff80\uff90derived nitrogen (N) loading in terrestrial ecosystems has caused widespread ecosystem\uffe2\uff80\uff90level phosphorus (P) limitation. In response, plants and soil micro\uffe2\uff80\uff90organisms adopt a series of P\uffe2\uff80\uff90acquisition strategies to offset N loading\uffe2\uff80\uff90induced P limitation. Many of these strategies impose costs on carbon (C) allocation by plants and soil micro\uffe2\uff80\uff90organisms; however, it remains unclear how P\uffe2\uff80\uff90acquisition 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\uffe2\uff80\uff90acquisition 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\uffe2\uff80\uff90level P limitation.
Long\uffe2\uff80\uff90term N loading can cause plants and soil micro\uffe2\uff80\uff90organisms 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\uffe2\uff80\uff90mineralizing and P\uffe2\uff80\uff90solubilizing micro\uffe2\uff80\uff90organisms. 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 stabilization. Increased relative abundances of P\uffe2\uff80\uff90mineralizing and P\uffe2\uff80\uff90solubilizing bacteria can accelerate P mining and SOC decay, which may decrease microbial C use efficiency and subsequently lower SOC sequestration.
The trade\uffe2\uff80\uff90offs between different plant P\uffe2\uff80\uff90acquisition strategies under N loading should be among future research priorities due to their cascading impacts on soil C storage. Quantifying ecosystem thresholds for P adaption to increased N loading is important because P\uffe2\uff80\uff90acquisition strategies are effective when N loading is below the N threshold. Moreover, understanding the response of P\uffe2\uff80\uff90acquisition strategies at different levels of native soil N availability could provide insight to divergent P\uffe2\uff80\uff90acquisition strategies across sites and ecosystems. Altogether, P\uffe2\uff80\uff90acquisition strategies should be explicitly considered in Earth System Models to generate more realistic predictions of the effects of N loading on soil C cycling.
Read the free Plain Language Summary for this article on the Journal blog.Data for manuscript The data provided in the present document corresponds to the manuscript: Engedal, T., Magid, J., Hansen, V., Rasmussen, J., S\u00f8rensen, H., Jensen, L. S. (2023): Cover crop root morphology rather than quality controls the fate of root and rhizodeposition C into distinct soil C pools. Global Change Biology, in press. Short abstract In order to investigate the fate of cover crop-derived belowground C as rhizodeposition and, over time, into the distinct soil organic carbon pools of particulate- and mineral-associated organic carbon (POC and MAOC), a column trial was esblished with 0.25 m top soil and 0.25 m sub soil. Four cover crops were grown for 3 months and 14CO2-labelled twice a week. Four out of eight replicate columns were destructively harvested to quantify root C and the carbon lost via rhizodeposition in absolute (qClvR) and relative terms (%ClvR) in bulk soil and rhizosphere soil from top- and subsoil (t1). The other four replicate columns were harvested for undisturbed incubation for one year, before final sampling (t2). Bulk soil from both sampling times were subject to a simple fractionation protocol by size, where particles larger from 50 microns were assigned to POC and smaller than 50 microns assigned to MAOC after dispersion in NaHMP. All fractions were dried, weighed and analyzed for 14C activity as disintegrations per minute (DPM). Further details Column ID 1-16 refer to columns sampled at t1, while column ID 17-32 refer to columns sampled at t2. Underlying assumptions and detailed descriptions of the different fractions are to be found in the manuscript.", "keywords": ["2. Zero hunger", "MOAM", "POM", "MAOC", "cover crop", "15. Life on land", "soil organic fractionation", "soil organic carbon", "mineral-associated organic matter", "rhizodeposition", "root morphology", "particulate organic matter", "root carbon", "POC"], "contacts": [{"organization": "Engedal, Tine, Magid, Jakob, Hansen, Veronika, Rasmussen, Jim, S\u00f8rensen, Helle, Jensen, Lars Stoumann,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.5281/zenodo.8090465"}, {"rel": "self", "type": "application/geo+json", "title": "10.5281/zenodo.8090465", "name": "item", "description": "10.5281/zenodo.8090465", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5281/zenodo.8090465"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2023-06-28T00:00:00Z"}}, {"id": "20.500.11755/caa0017e-1fa6-41ae-a8f0-8de3b4f939e4", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:22:12Z", "type": "Journal Article", "created": "2022-09-10", "title": "Nitrogen loading enhances phosphorus limitation in terrestrial ecosystems with implications for soil carbon cycling", "description": "Abstract
Increased human\uffe2\uff80\uff90derived nitrogen (N) loading in terrestrial ecosystems has caused widespread ecosystem\uffe2\uff80\uff90level phosphorus (P) limitation. In response, plants and soil micro\uffe2\uff80\uff90organisms adopt a series of P\uffe2\uff80\uff90acquisition strategies to offset N loading\uffe2\uff80\uff90induced P limitation. Many of these strategies impose costs on carbon (C) allocation by plants and soil micro\uffe2\uff80\uff90organisms; however, it remains unclear how P\uffe2\uff80\uff90acquisition 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\uffe2\uff80\uff90acquisition 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\uffe2\uff80\uff90level P limitation.
Long\uffe2\uff80\uff90term N loading can cause plants and soil micro\uffe2\uff80\uff90organisms 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\uffe2\uff80\uff90mineralizing and P\uffe2\uff80\uff90solubilizing micro\uffe2\uff80\uff90organisms. 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 stabilization. Increased relative abundances of P\uffe2\uff80\uff90mineralizing and P\uffe2\uff80\uff90solubilizing bacteria can accelerate P mining and SOC decay, which may decrease microbial C use efficiency and subsequently lower SOC sequestration.
The trade\uffe2\uff80\uff90offs between different plant P\uffe2\uff80\uff90acquisition strategies under N loading should be among future research priorities due to their cascading impacts on soil C storage. Quantifying ecosystem thresholds for P adaption to increased N loading is important because P\uffe2\uff80\uff90acquisition strategies are effective when N loading is below the N threshold. Moreover, understanding the response of P\uffe2\uff80\uff90acquisition strategies at different levels of native soil N availability could provide insight to divergent P\uffe2\uff80\uff90acquisition strategies across sites and ecosystems. Altogether, P\uffe2\uff80\uff90acquisition strategies should be explicitly considered in Earth System Models to generate more realistic predictions of the effects of N loading on soil C cycling.
Read the free Plain Language Summary for this article on the Journal blog.