瑞士洛桑大学Marie-Elodie Perga团队研究了方解石沉淀在湖泊碳循环过程中的作用。2024年11月1日出版的《科学进展》发表了这项成果。

据介绍，湖泊向大气中排放大量的二氧化碳（CO₂），其原因一直存在争议。长期以来，湖泊仅仅是土壤中泄露的有机物的呼吸器，但有证据表明，集水区基岩风化产生的无机碳也可能支持湖泊二氧化碳的排放，这一观点受到了挑战。无机碳输入最终如何产生湖泊二氧化碳脱气仍然是一个盲点。

研究团队在一维物理-生物地球化学耦合模型中开发并引入了一个方解石模块，以模拟日内瓦湖过去40年的碳循环。该团队研究人员论证了方解石沉淀过程，是如何在年度尺度上增加二氧化碳净排放量的。结果表明，方解石沉淀可以解释全球各种湖泊（包括世界上一些最大的湖泊）的二氧化碳的释放，而绝非奇谈怪论。

附：英文原文

Title: Calcite precipitation: The forgotten piece of lakes’ carbon cycle

Author: Gal Many, Nicolas Escoffier, Pascal Perolo, Fabian Brenbold, Damien Bouffard, Marie-Elodie Perga

Issue&Volume: 2024-11-01

Abstract: Lakes emit substantial amounts of carbon dioxide (CO₂) into the atmosphere, but why they do remains debated. The long-standing vision of lakes as solely respirators of the organic matter leaking from the soils has been challenged by evidence that inorganic carbon produced by weathering of the catchment bedrock could also support lake CO₂ emissions. How inorganic carbon inputs ultimately generate lake CO₂ outgassing remains a blind spot. We develop and introduce a calcite module in a coupled one-dimensional physical-biogeochemical model that we use to simulate the carbon cycle of the large Lake Geneva over the past 40 years. We mechanistically demonstrate how the so-far neglected process of calcite precipitation boosts net CO₂ emissions at the annual scale. Far from being anecdotal, we show that calcite precipitation could explain CO₂ outgassing across various lakes globally, including some of the largest lakes in the world.

DOI: ado5924

Source: https://www.science.org/doi/10.1126/sciadv.ado5924