Sedimentary high molecular weight (HMW) n-alkyl lipids derived from the waxes of terrestrial plants are common target compounds in biogeochemical and paleoenvironmental research. These plant waxes derive predominantly from the epicuticular cover of vascular plant leaves and their relative and absolute abundances and stable isotopic composition can be used as proxies to decipher, e.g., continental climate and land-ocean carbon transfer processes. In marine sediments, however, compound-specific radiocarbon analysis has revealed that plant waxes are often not syn-depositional, but instead are substantially ¹⁴C-depleted (‘pre-aged’) upon deposition. This ¹⁴C-depletion can be caused by various processes that either promote retention of plant waxes during transport from source to sink such as storage in soils or entrainment in deposition-resuspension loops in rivers and on continental shelves or, alternatively, by processes that add HMW n-alkyl lipids from other sources (e.g., petrogenic inputs). Here, we review the intrinsic and extrinsic processes affecting the sedimentary plant wax ¹⁴C composition (ranging from chemical processes to continental-scale environmental conditions), how plant wax ¹⁴C compositions translate into mean ages, and which processes control plant wax mean ages in marine sediments. Finally, we use a compilation of available and new compound-specific plant wax ¹⁴C data to provide a synthesis and evaluate the major controls on plant wax mean ages in marine sediments at the global scale.

源自陆生植物蜡的沉积高分子量 (HMW)正烷基脂质是生物地球化学和古环境研究中常见的目标化合物。这些植物蜡主要来自维管植物叶子的表皮覆盖物，它们的相对和绝对丰度以及稳定的同位素组成可用作破译大陆气候和陆地 - 海洋碳转移过程的代理。然而，在海洋沉积物中，特定化合物的放射性碳分析表明，植物蜡通常不是顺沉积的，而是在沉积时大量消耗¹⁴ C（“预老化”）。这¹⁴C-消耗可能由促进植物蜡在从源到汇的运输过程中保留的各种过程引起，例如储存在土壤中或夹带在河流和大陆架上的沉积-再悬浮循环中，或者由添加 HMW n 的过程引起-来自其他来源的烷基脂质（例如，石油输入）。在这里，我们回顾了影响沉积植物蜡¹⁴ C 成分的内在和外在过程（从化学过程到大陆尺度的环境条件），植物蜡¹⁴ C 成分如何转化为平均年龄，以及哪些过程控制植物蜡平均年龄海洋沉积物。最后，我们使用可用的和新的特定化合物植物蜡的汇编¹⁴C 数据提供综合和评估对全球范围海洋沉积物中植物蜡平均年龄的主要控制。