Ironstone, phosphorite, and nutrient cycling during Paleozoic biodiversification

铁矿和磷矿是具有重要科学和工业意义的海洋化学沉积物。铁石富含铁，铁不仅是炼钢所必需的，也是几乎所有生物所必需的。它是植物光合作用所必需的，是许多蛋白质的一部分，并参与其他营养元素循环的微生物代谢。磷矿是肥料中磷的最重要来源，因此对养活地球上迅速增长的人口至关重要。和铁一样，P也是一种生物必需元素。它形成骨架，是DNA的组成部分，对细胞能量转移至关重要，并在地质时间尺度上限制生物生产力。因为铁矿和磷矿的沉淀与生物学密切相关，这些沉积物不仅仅是地质过程的记录者，而且与地球系统的演化密切相关。

Ironstone and phosphorite are marine chemical sediments of scientific and industrial importance. Ironstone is enriched in Fe, which is not only required for steel production, but also essential for nearly all living things. It is necessary for photosynthesis in plants, part of many proteins, and involved in microbial metabolisms that cycle other nutrient elements. Phosphorite is the most important source of P in fertilizer, and therefore vital for feeding the Earth’s burgeoning population. Like Fe, P is also a bioessential element. It forms skeletons, is a building block of DNA, is essential for cellular energy transfer, and limits biologic productivity over geologic timescales. Because the precipitation of ironstone and phosphorite is so closely tied to biology, these deposits are not simply recorders of geologic processes, but intimately involved in Earth system evolution.