Dataset Information

Nitrogen and phosphorus cycling in an ombrotrophic peatland: a benchmark for assessing change.

ABSTRACT:

Aims

Slow decomposition and isolation from groundwater mean that ombrotrophic peatlands store a large amount of soil carbon (C) but have low availability of nitrogen (N) and phosphorus (P). To better understand the role these limiting nutrients play in determining the C balance of peatland ecosystems, we compile comprehensive N and P budgets for a forested bog in northern Minnesota, USA.

Methods

N and P within plants, soils, and water are quantified based on field measurements. The resulting empirical dataset are then compared to modern-day, site-level simulations from the peatland land surface version of the Energy Exascale Earth System Model (ELM-SPRUCE).

Results

Our results reveal N is accumulating in the ecosystem at 0.2 ± 0.1 g N m^-2 year^-1 but annual P inputs to this ecosystem are balanced by losses. Biomass stoichiometry indicates that plant functional types differ in N versus P limitation, with trees exhibiting a stronger N limitation than ericaceous shrubs or Sphagnum moss. High biomass and productivity of Sphagnum results in the moss layer storing and cycling a large proportion of plant N and P. Comparing our empirically-derived nutrient budgets to ELM-SPRUCE shows the model captures N cycling within dominant plant functional types well.

Conclusions

The nutrient budgets and stoichiometry presented serve as a baseline for quantifying the nutrient cycling response of peatland ecosystems to both observed and simulated climate change. Our analysis improves our understanding of N and P dynamics within nutrient-limited peatlands and represents a crucial step toward improving C-cycle projections into the twenty-first century.

SUBMITTER: Salmon VG

PROVIDER: S-EPMC9580354 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Publications

Nitrogen and phosphorus cycling in an ombrotrophic peatland: a benchmark for assessing change.

Salmon Verity G VG Brice Deanne J DJ Bridgham Scott S Childs Joanne J Graham Jake J Griffiths Natalie A NA Hofmockel Kirsten K Iversen Colleen M CM Jicha Terri M TM Kolka Randy K RK Kostka Joel E JE Malhotra Avni A Norby Richard J RJ Phillips Jana R JR Ricciuto Daniel D Schadt Christopher W CW Sebestyen Stephen D SD Shi Xiaoying X Walker Anthony P AP Warren Jeffrey M JM Weston David J DJ Yang Xiaojuan X Hanson Paul J PJ

Plant and soil 20210701

<h4>Aims</h4>Slow decomposition and isolation from groundwater mean that ombrotrophic peatlands store a large amount of soil carbon (C) but have low availability of nitrogen (N) and phosphorus (P). To better understand the role these limiting nutrients play in determining the C balance of peatland ecosystems, we compile comprehensive N and P budgets for a forested bog in northern Minnesota, USA.<h4>Methods</h4>N and P within plants, soils, and water are quantified based on field measurements. Th ...[more]

PMID: 36267144

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Dataset Information

Nitrogen and phosphorus cycling in an ombrotrophic peatland: a benchmark for assessing change.

Aims

Methods

Results

Conclusions

Publications

Nitrogen and phosphorus cycling in an ombrotrophic peatland: a benchmark for assessing change.

Similar Datasets

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