The dust cycle facilitates the exchange of particles among Earth's major systems, enabling dust to traverse ecosystems, cross geographic boundaries, and even move uphill against the natural flow of gravity. Dust in the atmosphere is composed of a complex and ever-changing mixture that reflects the evolving human footprint on the landscape. The emission, transport, and deposition of dust interacts with and connects Critical Zone processes at all spatial and temporal scales. Landscape properties, land use, and climatic factors influence the wind erosion of soil and nutrient loss, which alters the long-term ecological dynamics at erosional locations. Once in the atmosphere, dust particles influence the amount of solar radiation reaching Earth, and interact with longwave (terrestrial) radiation, with cascading effects on the climate system. Finally, the wet and dry deposition of particles influences ecosystem structure, composition, and function over both short and long-term scales. Tracking dust particles from source to sink relies on monitoring and measurement of the geochemical composition and size distribution of the particles, space-borne and ground-based remote sensing, and dust modeling. Dust is linked to human systems via land use and policies that contribute to dust emissions and the health-related consequences of particulate loads and composition. Despite the significant influence dust has in shaping coupled natural-human systems, it has not been considered a key component of the Critical Zone. Here, we demonstrate that dust particles should be included as a key component of the Critical Zone by outlining how dust interacts with and shapes Earth System processes from generation, through transport, to deposition. We synthesize current understanding from global research and identify critical data and knowledge gaps while showcasing case studies from North America.

中文翻译：

---

关键区域的粉尘：北美案例研究


尘埃循环促进了地球主要系统之间的粒子交换，使尘埃能够穿越生态系统、跨越地理边界，甚至逆着自然重力流向上移动。大气中的尘埃由复杂且不断变化的混合物组成，反映了人类在景观上不断变化的足迹。尘埃的排放、传输和沉积在所有空间和时间尺度上都与临界区过程相互作用并相互联系。景观特性、土地利用和气候因素会影响土壤的风蚀和养分流失，从而改变侵蚀地点的长期生态动态。一旦进入大气层，尘埃颗粒就会影响到达地球的太阳辐射量，并与长波（地面）辐射相互作用，对气候系统产生级联效应。最后，颗粒的湿沉降和干沉降在短期和长期尺度上影响生态系统的结构、组成和功能。从源头到汇跟踪尘埃颗粒依赖于对颗粒物的地球化学成分和粒径分布的监测和测量、星载和地基遥感以及尘埃建模。灰尘通过土地使用和政策与人类系统相关联，这些政策导致了灰尘排放以及颗粒物负荷和成分对健康的相关后果。尽管尘埃对塑造自然-人类耦合系统有重大影响，但它并未被视为临界区的关键组成部分。在这里，我们通过概述尘埃如何与地球系统从产生、运输到沉积的过程相互作用并塑造尘埃颗粒，证明尘埃颗粒应作为关键区的关键组成部分。 我们综合了当前对全球研究的理解，确定了关键数据和知识差距，同时展示了北美的案例研究。