Gross primary production (GPP) is a fundamental ecosystem process that sequesters carbon dioxide (CO₂) and forms the resource base for higher trophic levels. Still, the relative contribution of different controls on GPP at the whole-ecosystem scale is far from resolved. Here we show, by manipulating CO₂ concentrations in large-scale experimental pond ecosystems, that CO₂ availability is a key driver of whole-ecosystem GPP. This result suggests we need to reformulate past conceptual models describing controls of lake ecosystem productivity and include our findings when developing models used to predict future lake ecosystem responses to environmental change.

中文翻译：

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二氧化碳刺激了湖泊的初级生产。

初级生产总值（GPP）是一种基本的生态系统过程，会隔离二氧化碳（CO ₂）并形成更高营养级别的资源基础。尽管如此，在整个生态系统规模上，不同控件对GPP的相对贡献还远未解决。在这里，我们通过控制大型实验池塘生态系统中的CO ₂浓度，表明CO _2的可用性是整个生态系统GPP的关键驱动力。该结果表明，我们需要重新描述过去描述湖泊生态系统生产力控制的概念模型，并在开发用于预测未来湖泊生态系统对环境变化的响应的模型时纳入我们的发现。