农业土壤中的碳封存具有减少温室气体排放的能力，以及改善土壤生物，物理，和化学性质。对有关澳大利亚谷物耕作系统中土壤有机碳（SOC）动态的文献的回顾并不能使我们得出最佳耕作方法，以增加或维持土壤和气候的特定组合的SOC。本研究旨在进一步探索土壤之间复杂的相互作用,气候,和SOC上的耕作方式。我们用农业生产系统模型框架进行了建模研究，通过结合对比澳大利亚的土壤，气候,和耕作实践(作物轮作，和轮换中的管理，比如受精，耕作,和残留物管理)在阶乘设计中。这种设计导致了我们模拟中对比土壤和气候的换位，提供研究区域中未发生的土壤气候组合，以帮助了解气候限制对SOC的重要性。我们对模型的输出进行了统计分析，以确定土壤参数的相对贡献，气候,和SOC上的耕作方式。初始SOC含量对SOC值影响最大,其次是气候和施肥实践。这些因素解释了66％，18％和15％的SOC变化，分别,经过80年的模拟农业实践。耕作和留茬管理对SOC的影响最小。这项研究强调了小麦-鹰嘴豆轮作中鹰嘴豆阶段对SOC的可能负面影响以及亚热带气候中覆盖作物的潜在积极影响（QLD，澳大利亚）关于SOC。它还显示了管理实现增加SOC的复杂性，同时旨在最大程度地减少农业系统中的一氧化二氮（N2O）排放和硝酸盐浸出。在我们的模拟中，对比土壤和气候的换位揭示了气候限制对SOC的重要性。
Carbon sequestration in agricultural soils has the capacity to mitigate greenhouse gas emissions, as well as to improve soil biological, physical, and chemical properties. The review of literature pertaining to soil organic carbon (SOC) dynamics within Australian grain farming systems does not enable us to conclude on the best farming practices to increase or maintain SOC for a specific combination of soil and climate. This
study aimed to further explore the complex interactions of soil, climate, and farming practices on SOC. We undertook a modeling
study with the Agricultural Production Systems sIMulator modeling framework, by combining contrasting Australian soils, climates, and farming practices (crop rotations, and management within rotations, such as fertilization, tillage, and residue management) in a factorial design. This design resulted in the transposition of contrasting soils and climates in our simulations, giving soil-climate combinations that do not occur in the
study area to help provide insights into the importance of the climate constraints on SOC. We statistically analyzed the model\'s outputs to determinate the relative contributions of soil parameters, climate, and farming practices on SOC. The initial SOC content had the largest impact on the value of SOC, followed by the climate and the fertilization practices. These factors explained 66, 18, and 15% of SOC variations, respectively, after 80 years of constant farming practices in the simulation. Tillage and stubble management had the lowest impacts on SOC. This
study highlighted the possible negative impact on SOC of a chickpea phase in a wheat-chickpea rotation and the potential positive impact of a cover crop in a sub-tropical climate (QLD, Australia) on SOC. It also showed the complexities in managing to achieve increased SOC, while simultaneously aiming to minimize nitrous oxide (N2O) emissions and nitrate leaching in farming systems. The transposition of contrasting soils and climates in our simulations revealed the importance of the climate constraints on SOC.
PDF(Sci-hub)