土壌の深さの関数として大気と土壌の炭素転送
Jérôme Balesdent1, Isabelle Basile-Doelsch2, Joël Chadoeuf3
1Aix-Marseille Université, CNRS, IRD, INRA, Coll France, CEREGE, Aix en Provence, France. jerome.balesdent@inra.fr.
Nature
|July 12, 2018
まとめ
土壌有機炭素 (SOC) の深層貯蔵は,気候と農業にとって極めて重要です. 最近の炭素吸収は主に浅い土層で起こっており,深い地下には発生せず,土壌の炭素管理戦略に影響を与えています.
科学分野:
- 土壌科学
- 気候科学
- エコロジー
背景:
- 土壌の有機炭素の交換は気候と農業の生産性に影響を及ぼします.
- 表面土壌の炭素動態は理解されていますが,深層土壌の炭素交換 (30cm以下) は不明です.
- この知識のギャップは,効果的な土壌炭素管理とグローバルな炭素モデルを制限しています.
研究 の 目的:
- 土壌全体のプロファイルに近年の大気中の炭素を定量化します.
- 最近統合されたSOCの様々な生態系における深度分布を分析する.
- 深い土壌の炭素吸収に影響を与える要因を特定する.
主な方法:
- 112の場所からの安定した炭素同位体シグネチャのメタ分析 (1965年−2015年).
- 草原,森林,農地が様々な気候圏に含まれています.
- 炭素吸収の深さとその気候と土地利用との関係の分析
主要な成果:
- 地下 (30~100cm) はSOCの47%を占めるが,最近吸収されたSOCは19%しか占めていない.
- 炭鉱土壌に最近吸収された炭素の平均深さは10cmです.
- 温度ではなく乾燥度指数は,深層の土壌への炭素配分をよりよく説明します.作物の土地の使用は,表面SOCの組み込みを減少させます.
結論:
- 土壌の深さは SOCの動態と気候と土地利用への反応に大きな影響を与えます.
- 現在の世界的な炭素モデルは 深い土壌の炭素貯蔵を過小評価しているかもしれません
- 土壌と大気の炭素交換の理解を深めるために多層の土壌モジュールが必要です.
さらに関連する動画
関連する概念動画
The Soil Ecosystem
24.9K
Plants obtain inorganic minerals and water from the soil, which acts as a natural medium for land plants. The composition and quality of soil depend not only on the chemical constituents but also on the presence of living organisms. In general, soils contain three major components:
24.9K
The Carbon Cycle
43.9K
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
43.9K
Transfer Function to State Space
811
State-space representation is a powerful tool for simulating physical systems on digital computers, necessitating the conversion of the transfer function into state-space form. Consider an nth-order linear differential equation with constant coefficients, like those encountered in an RLC circuit. The state variables are selected as the output and its n−1 derivatives. Differentiating these variables and substituting them back into the original equation produces the state equations.
In an RLC...
In an RLC...
811
State Space to Transfer Function
591
The conversion of state-space representation to a transfer function is a fundamental process in system analysis. It provides a method for transitioning from a time-domain description to a frequency-domain representation, which is crucial for simplifying the analysis and design of control systems.
The transformation process begins with the state-space representation, characterized by the state equation and the output equation. These equations are typically represented as:
The transformation process begins with the state-space representation, characterized by the state equation and the output equation. These equations are typically represented as:
591
Transfer function and Bode Plots-II
782
In the standard form, the transfer function is shown in constant gain, poles/zeros at origin, simple poles/zeros, and quadratic poles/zeros; each contributing uniquely to the system's overall response. The term represents the magnitude of the simple zero:
782
Transfer function and Bode Plots-I
741
A transfer function presented in its standard form integrates elements' constant gain, the zeros, and poles at the origin, simple zeros and poles, and quadratic poles and zeros. The transfer function can be written as H(ω):
741


