Where does desert dust originate? Geomorphic and climatic control on the evolution of dust sources in the Mojave Desert, USA.

沙漠本质上是尘土飞扬的环境，目前的许多文献和科学研究都断言，干燥的湖床或playas是灰尘的主要来源，尽管它们只占沙漠景观的很小一部分。在美国西南部的莫哈韦沙漠东部，在大约1万年前的一次气候转变中，古老的湖泊沉积物促成了沙丘和尘埃的形成。然而，大量灰尘堆积的年龄较年轻，这表明在过去，除了playas之外，地貌也是重要的灰尘来源。这项建议的总体目标有三个方面：1)确定哪些沙漠地形提供的灰尘通过使用新的风洞技术来源,便携式原位风蚀实验室(PI-SWERL), 2)确定粉尘来源已经改变随着时间的推移,通过使用现代尘源模拟预测哪些地形排放粉尘在过去,并通过比较颞尘埃组成的变化和潜在的来源,和3)确定记录的尘埃在沙漠土壤对应于沙丘活动的年龄,利用光激发光技术测定土壤尘埃中沙粒的年龄。从这项研究中，我们将了解到更多关于沙漠环境中与粉尘排放相关的地貌和土壤性质的信息，以及这些来源如何随着地貌过程和气候变化而变化。从科学的角度来看，沙尘很重要，因为沙尘添加到土壤中控制着土壤的形成、土壤水文、景观演变和沙漠植物的生态功能。粉尘产生是一个与能见度、安全和健康问题有关的社会问题。这项研究的广泛影响包括与其他大学和研究人员的合作，年龄控制和风蚀技术和技术的持续发展，以及大学生的支持，他们将获得宝贵的领域和科学经验。这项研究的结果将在一次主要会议上提出，在同行审查的科学杂志上发表，并提供给城市/道路规划者和公园和娱乐地区的管理人员使用。

Deserts are by nature dusty environments, and much of the current literature and scientific research has asserted that dry lake beds, or playas, are the major source of dust despite the fact that they make up a very small proportion of the desert landscape. In the eastern Mojave Desert, southwestern United States, ancient lake sediments contributed to the formation of sand dunes and dust during a climatic transition about 10,000 years ago. However, a large amount of dust accumulations are younger in age, suggesting that landforms other than playas have been significant sources of dust in the past. The overall goal of this proposal is three-fold: 1) determine which desert landforms provide sources of dust by using new wind tunnel technology, the Portable In Situ Wind Erosion Lab (PI-SWERL), 2) determine if the dust sources have changed over time by using modern dust sources as analogs to predict which landforms emitted dust in the past, and by comparing temporal changes in the composition of dust and potential sources, and 3) determine if the record of dust in desert soils corresponds to the age of sand dune activity, using optically stimulated luminescence technology to determine the ages of sand grains within the soil dust. From this research, more information will be learned regarding the types of landforms and soil properties associated with dust emissions in desert environments, and how these sources might change in response to geomorphic processes and climate change. Dust is important from a scientific standpoint because dust additions to soils control soil formation, soil hydrology, landscape evolution, and the ecologic function of desert plants. Dust generation is a societal concern related to visibility, safety, and health issues. Broader impacts of this research include collaboration with other universities and researchers, continued development of age control and wind erosion technologies and techniques, and the support of university students who will gain valuable field and scientific experience. The results of this research will be presented at a major conference, published in peer-reviewed scientific journals, and provided to city/road planners and park and recreational area managers for their use.