Modeling the Carbon Cost of Plant Nitrogen and Phosphorus Uptake Across Temperate and Tropical Forests

Frontiers in Forests and Global Change, Journal Year: 2020, Volume and Issue: 3

Published: May 21, 2020

Nutrient limitation is a key source of uncertainty in predicting terrestrial carbon (C) uptake. Models have begun to include nitrogen (N) dynamics; however, phosphorus (P), which can also limit or co-limit net primary production (NPP) many ecosystems, currently absent most models. To meet this challenge, we integrated P dynamics into cutting-edge plant nutrient uptake model (Fixation and Uptake Nitrogen: FUN 2.0) that mechanistically tracks the C cost N from soil based on allocating leaf resorption root/root-microbial uptake, availability soil. We incorporated direct as well synthesizing phosphatase enzymes extract soil, new formulation Nutrients: 3.0). confronted validated 3.0 against empirical estimates canopy, root, pools 45 temperate forest plots Indiana, USA 18 tropical dry located Guanacaste, Costa Rica vary distribution arbuscular mycorrhizal- (AM) ectomycorrhizal- (ECM) associated trees. was able accurately predict retranslocation across sites (slopes 0.95 0.92 for retranslocation, respectively). Carbon costs acquiring were three times higher compared sites, driving overall sites. In addition, lead substantial increase fixation support enzyme production. Sensitivity analyses showed appeared be severely limited, while evidence co-limitation by P. Collectively, provides novel framework coupled earth system models leverage enhance predictions ecosystem response global change.

Language: Английский

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Bringing function to structure: Root–soil interactions shaping phosphatase activity throughout a soil profile in Puerto Rico

Ecology and Evolution, Journal Year: 2021, Volume and Issue: 11(3), P. 1150 - 1164

Published: Jan. 19, 2021

Abstract Large areas of highly productive tropical forests occur on weathered soils with low concentrations available phosphorus (P). In such forests, root and microbial production acid phosphatase enzymes capable mineralizing organic is considered vital to increasing P for plant uptake. We measured both soil throughout depth alongside a variety factors better understand the potential roots biota increase availability constrain estimates biochemical mineralization within ecosystem models. down 1 m, 30 cm, collected data fine‐root mass density, specific length, P, bulk texture using cores in four Luquillo Experimental Forest Puerto Rico. found that decreased depth, but not phosphatase. Furthermore, when were expressed per volume, was 100‐fold higher Both influenced Soil increased density which together explained over 50% variation Over 80% unit attributed length (positive correlation) (resin) (negative correlation). Synthesis : Fine‐root traits are necessary represent activity column across sites different conditions tree species. These findings can be used parameterize or benchmark models contain biomass distributions depth.

Language: Английский

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Tradeoffs and Synergies in Tropical Forest Root Traits and Dynamics for Nutrient and Water Acquisition: Field and Modeling Advances

Frontiers in Forests and Global Change, Journal Year: 2021, Volume and Issue: 4

Published: Dec. 2, 2021

Vegetation processes are fundamentally limited by nutrient and water availability, the uptake of which is mediated plant roots in terrestrial ecosystems. While tropical forests play a central role global water, carbon, cycling, we know very little about tradeoffs synergies root traits that respond to resource scarcity. Tropical trees face unique set limitations, with rock-derived nutrients moisture seasonality governing many ecosystem functions, versus availability often separated spatially temporally. Root characterize biomass, depth distributions, production phenology, morphology, physiology, chemistry, symbiotic relationships can be predictive plants’ capacities access acquire links aboveground like transpiration, wood productivity, leaf phenology. In this review, identify an emerging trend literature fine biomass surface soils greatest infertile or sufficiently moist soils. We also interesting paradoxes forest responses changing resources merit further exploration. For example, specific length, typically increases under scarcity expand volume soil explored, instead increase greater base cation both across natural gradients fertilization experiments. Also, additions, rather than reducing mycorrhizal colonization as might expected, increased rates scenarios some forests. Efforts include functions vegetation models have grown more sophisticated over time, yet there disconnect between emphasis characterizing carbon costs field experiments on measuring production, morphology response changes availability. Closer integration modeling efforts could connect mechanistic investigation fine-root dynamics ecosystem-scale understanding allowing us better predict forest-climate feedbacks.

Language: Английский

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Phosphorus limitation of early growth differs between nitrogen‐fixing and nonfixing dry tropical forest tree species

New Phytologist, Journal Year: 2022, Volume and Issue: 237(3), P. 766 - 779

Published: Nov. 10, 2022

Summary Tropical forests are often characterized by low soil phosphorus (P) availability, suggesting that P limits plant performance. However, how seedlings from different functional types respond to availability is poorly known but important for understanding and modeling forest dynamics under changing environmental conditions. We grew four nitrogen (N)‐fixing Fabaceae seven diverse non‐N‐fixing tropical dry tree species in a shade house three fertilization treatments evaluated carbon (C) allocation responses, demand, P‐use, investment acquisition traits, correlations among traits. Nitrogen fixers larger with increasing addition contrast non‐N fixers, which showed fewer responses C use. Foliar increased both types, while strategies did not vary differed between N showing higher root phosphatase activity (RPA) than nonfixers. Growth suggest limited P, nonfixers may be other resources. regardless of limitation, traits such as mycorrhizal colonization RPA were nonplastic across steep gradient. Differential limitation has implications succession earth system models.

Language: Английский

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Phosphorus is the key soil indicator controlling productivity in planted Masson pine forests across subtropical China

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 822, P. 153525 - 153525

Published: Jan. 29, 2022

Language: Английский

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