Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests

Cusack, D; Silver, W L; Torn, M S; McDowell, W H

doi:10.1007/s10533-010-9496-4

Title: Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests

Full Record
Other Related Research

Abstract

Anthropogenic nitrogen (N) deposition is increasing rapidly in tropical regions, adding N to ecosystems that often have high background N availability. Tropical forests play an important role in the global carbon (C) cycle, yet the effects of N deposition on C cycling in these ecosystems are poorly understood. We used a field N-fertilization experiment in lower and upper elevation tropical rain forests in Puerto Rico to explore the responses of above- and belowground C pools to N addition. As expected, tree stem growth and litterfall productivity did not respond to N fertilization in either of these Nrich forests, indicating a lack of N limitation to net primary productivity (NPP). In contrast, soil C concentrations increased significantly with N fertilization in both forests, leading to larger C stocks in fertilized plots. However, different soil C pools responded to N fertilization differently. Labile (low density) soil C fractions and live fine roots declined with fertilization, while mineral-associated soil C increased in both forests. Decreased soil CO2 fluxes in fertilized plots were correlated with smaller labile soil C pools in the lower elevation forest (R2 = 0.65, p\0.05), and with lower live fine root biomass in the upper elevation forest (R2 = 0.90,more »« less

Authors:: Cusack, D; Silver, W L; Torn, M S; McDowell, W H

Publication Date:: Fri Apr 15 00:00:00 EDT 2011

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:: Earth Sciences Division

OSTI Identifier:: 1051650

Report Number(s):: LBNL-5143E
Journal ID: ISSN 0168--2563

DOE Contract Number:: DE-AC02-05CH11231

Resource Type:: Journal Article

Journal Name:: Biogeochemistry

Additional Journal Information:: Journal Volume: 104; Journal Issue: 1-3; Related Information: Journal Publication Date: 2011; Journal ID: ISSN 0168--2563

Country of Publication:: United States

Language:: English

Subject:: 54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; Aboveground biomass; Dissolved organic carbon; Nutrient limitation; Roots; Soil density fractions; Soil respiration

Citation Formats


                    Cusack, D, Silver, W L, Torn, M S, and McDowell, W H. Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests.  United States: N. p., 2011. 
        Web.  doi:10.1007/s10533-010-9496-4.

Copy to clipboard


                    Cusack, D, Silver, W L, Torn, M S, & McDowell, W H. Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests.  United States.  https://doi.org/10.1007/s10533-010-9496-4

Copy to clipboard


                    Cusack, D, Silver, W L, Torn, M S, and McDowell, W H. 2011.  
        "Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests".  United States.  https://doi.org/10.1007/s10533-010-9496-4.  https://www.osti.gov/servlets/purl/1051650.

Copy to clipboard


                    
@article{osti_1051650,

  title        = {Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests},

  author       = {Cusack, D and Silver, W L and Torn, M S and McDowell, W H},

  abstractNote = {Anthropogenic nitrogen (N) deposition is increasing rapidly in tropical regions, adding N to ecosystems that often have high background N availability. Tropical forests play an important role in the global carbon (C) cycle, yet the effects of N deposition on C cycling in these ecosystems are poorly understood. We used a field N-fertilization experiment in lower and upper elevation tropical rain forests in Puerto Rico to explore the responses of above- and belowground C pools to N addition. As expected, tree stem growth and litterfall productivity did not respond to N fertilization in either of these Nrich forests, indicating a lack of N limitation to net primary productivity (NPP). In contrast, soil C concentrations increased significantly with N fertilization in both forests, leading to larger C stocks in fertilized plots. However, different soil C pools responded to N fertilization differently. Labile (low density) soil C fractions and live fine roots declined with fertilization, while mineral-associated soil C increased in both forests. Decreased soil CO2 fluxes in fertilized plots were correlated with smaller labile soil C pools in the lower elevation forest (R2 = 0.65, p\0.05), and with lower live fine root biomass in the upper elevation forest (R2 = 0.90, p\0.05). Our results indicate that soil C storage is sensitive to N deposition in tropical forests, even where plant productivity is not N-limited. The mineral-associated soil C pool has the potential to respond relatively quickly to N additions, and can drive increases in bulk soil C stocks in tropical forests.},

  doi          = {10.1007/s10533-010-9496-4},

  url          = {https://www.osti.gov/biblio/1051650},
  journal      = {Biogeochemistry},

  issn         = {0168--2563},

  number       = 1-3,

  volume       = 104,

  place        = {United States},

  year         = {Fri Apr 15 00:00:00 EDT 2011},

  month        = {Fri Apr 15 00:00:00 EDT 2011}

}

Copy to clipboard

Journal Article:

View Journal Article (0.59 MB)

https://doi.org/10.1007/s10533-010-9496-4

Other availability

Find in Google Scholar

Search WorldCat to find libraries that may hold this journal

Save / Share:

Export Metadata

Save to My Library

Similar records in OSTI.GOV collections:

Consequences of Altered Root Nutrient Uptake for Soil Carbon Stabilization (Final Report)

Technical Report Cusack, Daniela; Turner, Benjamin; Wright, S; ...

Objectives: The primary objectives of this project are to improve our understanding of tropical forest belowground processes, and to increase representation of this biome in ecosystem-scale and global C cycle models. Belowground dynamics present a major source of uncertainty inhibiting our ability to predict C cycle responses to climate change. Representation of tropical forests in these models is particularly lacking, even though these ecosystems hold >25% of terrestrial C stocks. While the majority of humid tropical forests exist on relatively infertile soils (i.e. poor in rock-derived nutrients), enormous gradients in soil nutrient availability exist at landscape-scales due to shifts inmore »« less
https://doi.org/10.2172/1763927

Full Text Available
Changes in microbial community characteristics and soil organic matter with nitrogen additions in two tropical forests

Journal Article Cusack, Daniela; Silver, Whendee; Torn, Margaret; ... - Ecology, 92(3):621-632

Microbial communities and their associated enzyme activities affect the amount and chemical quality of carbon (C) in soils. Increasing nitrogen (N) deposition, particularly in N-rich tropical forests, is likely to change the composition and behavior of microbial communities and feed back on ecosystem structure and function. This study presents a novel assessment of mechanistic links between microbial responses to N deposition and shifts in soil organic matter (SOM) quality and quantity. We used phospholipid fatty acid (PLFA) analysis and microbial enzyme assays in soils to assess microbial community responses to long-term N additions in two distinct tropical rain forests. Wemore »« less
https://doi.org/10.1890/10-0459.1
Reducing conditions, reactive metals, and their interactions can explain spatial patterns of surface soil carbon in a humid tropical forest

Journal Article Hall, Steven; Silver, Whendee - Biogeochemistry

Humid tropical forests support large stocks of surface soil carbon (C) that exhibit high spatial variability over scales of meters to landscapes (km). Reactive minerals and organo-metal complexes are known to contribute to C accumulation in these ecosystems, although potential interactions with environmental factors such as oxygen (O₂) availability have received much less attention. Reducing conditions can potentially contribute to C accumulation, yet anaerobic metabolic processes such as iron (Fe) reduction can also drive substantial C losses. We tested whether these factors could explain variation in soil C (0–10 and 10–20 cm depths) over multiple spatial scales in the Luquillo Experimentalmore »« less
https://doi.org/10.1007/s10533-015-0120-5

Full Text Available
Carbon Organisms Rhizosphere and Protection in Soil Environment model script and input data for soil moisture-respiration responses in tropical forests

Dataset Sulman, Benjamin; Cusack, Daniela

Objectives: Climatic drying is predicted for many tropical forests, yet models remain poorly parameterized for tropical forests, hampering predictions of forest-climate feedbacks. We applied an integrated model–experiment approach, parameterizing an ecosystem model Carbon Organisms Rhizosphere and Protection in the Soil Environment (CORPSE) with tropical forest observational data, and comparing model predictions with a field drying manipulation. We hypothesized that drying would suppress soil CO2 fluxes (i.e., respiration) in already-drier tropical forests, but increases CO2 fluxes in wetter tropical forests by alleviating anaerobiosis. We measured soil CO2 fluxes, soil moisture, soil temperature, and forest floor biomass during wet-dry cycles (2015 –more »« less
https://doi.org/10.15485/1960048

View Dataset
Competing effects of soil fertility and toxicity on tropical greening

Journal Article Fisher, Joshua; Perakalapudi, Naga; Turner, Benjamin; ... - Scientific Reports

Tropical forests are expected to green up with increasing atmospheric CO₂ concentrations, but primary productivity may be limited by soil nutrient availability. However, rarely have canopy-scale measurements been assessed against soil measurements in the tropics. Here, we sought to assess remotely sensed canopy greenness against steep soil nutrient gradients across 50 1-ha mature forest plots in Panama. Contrary to expectations, increases in in situ extractable soil phosphorus (P) and base cations (K, Mg) corresponded to declines in remotely sensed mean annual canopy greenness (r² = 0.77– 0.85; p < 0.1), controlling for precipitation. The reason for this inverse relationship appearsmore »« less
https://doi.org/10.1038/s41598-020-63589-1

Full Text Available

Similar Records