Buendia(iの頭は´),C., Kleidon,A. and Porporato,A.(2010): The role of tectonic uplift, climate and vegetation in the long-term terrestrial phosphorus cycle. Biogeosciences Discuss., 7, 301-333.

『長期の陸上リン循環における地殻構造の隆起と気候と植生の役割』


Abstract
 Phosphorus (P) is a crucial element for life and therefore for maintaining ecosystem productivity. Its local availability to the terrestrial biosphere results from the interaction between climate, tectonic uplift, atmospheric transport and biotic cycling. Here we present a mathematical model that describes the terrestrial P-cycle in a simple but comprehensive way. The resulting dynamical system can be solved analytically for steady-state conditions, allowing us to test the sensitivity of the P-availability to the key parameters and processes. Given constant inputs, we find that humid ecosystems exhibit lower P availability due to higher runoff and losses, and that tectonic uplift is a fundamental constraint. In particular, we find that in humid ecosystems the biotic cycling seem essential to maintain long-term P-availability. The time-dependent P dynamics for the Franz Josef and Hawaii chronosequences show how tectonic uplift is an important constraint on ecosystem productivity, while hydroclimatic conditions control the P-losses and speed towards steady-state. The model also helps describe how with limited uplift and atmospheric input, as in the case of the Amazon Basin, ecosystems must rely on mechanisms that enhance P-availability and retention. Our analysis underlines the need to include the P cycle in global vegetation-atmosphere models for a reliable representation of the response of the terrestrial biosphere to global change.』

1. Motivation
2. Model formulation
 2.1. Synthesis of the P-cycle model
 2.2. Climatic forcing
 2.3. Inputs
  2.3.1. Atmospheric transport and input from animals
  2.3.2. Input by tectonic and isostatic uplift
 2.4. Ecosystem internal fluxes
  2.4.1. Phosphorus weathering
  2.4.2. Formation of secondary minerals and P occlusion
  2.4.3. Vegetation P-uptake and litter fall
  2.4.4. P-mineralization
 2.5. Losses
 2.6. P-balance equations
3. Results
 3.1. Steady-state solution
  3.1.1. Sensitivity of ecosystems external inputs to soil moisture
  3.1.2. Sensitivity of organic biomass losses to soil moisture
  3.1.3. Sensitivity of active P uptake by vegetation to soil moisture
  3.1.4. Special solutions for systems without uplift
 3.2. Phosphorus temporal dynamics
  3.2.1. The Walker and Syers' model for New Zealand
  3.2.2. The Hawaii chronosequence
  3.2.3. Dynamics of an uplift dominated site (the Amazon Basin)
4. Summary and conclusions
Acknowledgements
References


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