碳循环科学示意图

一张复古自然历史风格的碳循环示意图，绘于暖象牙色纸张，细密交叉排线的手刻版画风格。五大碳库由标注通量箭头连接：海洋（波纹蓝灰）、森林（深绿针叶树轮廓）、大气（顶部浅蓝渐变带）、土壤（富棕色剖面）、工厂（黑色，冒烟）。各碳库附小棕褐字体的储量数值，弯曲通量箭头标注光合作用、呼吸作用、海洋吸收、化石燃料排放、分解等过程。做旧羊皮纸卷轴写道：「碳循环科学示意图」顶部窄衬线科学标题，右下角指南针玫瑰图。

A vintage natural-history illustration of the carbon cycle on warm ivory paper. Hand-engraving style with fine cross-hatching. Five main reservoirs connected by labelled flux arrows: an ocean (wavy blue-grey), a forest (dark green, conifer silhouettes), the atmosphere (pale blue gradient band at top), soil (rich brown cross-section), and a factory silhouette (black, emitting smoke). Each reservoir has a numeric stock value in tonnes in small sepia type. Flux arrows curve naturally between them, each labelled: "Photosynthesis", "Respiration", "Ocean absorption", "Fossil fuel emission", "Decomposition". Callout scroll in aged parchment reads: "Oceans absorb roughly one-quarter of all human CO₂ emissions each year." Scientific title in a narrow serif at top; compass rose at bottom-right corner.