RAPID: Sources and ecosystem significance of dust inputs during extremely wet and dry years in the Sierra Nevada, California

RAPID：加利福尼亚州内华达山脉极端潮湿和干燥年份灰尘输入的来源和生态系统重要性

• 批准号: 1744089
• 负责人: Emma Aronson
• 金额: $ 4万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1744089&HistoricalAwards=false
• 关键词: RAPID; Sources; ecosystem; significance; dust

Investigators have shown that, during drought, dust is important to soils in the Sierra Nevada, California (CA) and it is entering the Sierra from both the Central Valley (CA) and from the Gobi Desert, China, and that both sources bring in high-nutrient dust. These results are based on analyses of dust collected at the peak of the recent 2012-2016 drought, raising the question of whether the same trends would be observed during a wet year. Here, the team will collect new dust samples monthly to bi-monthly during the summer of 2017, following the recent wet winter of 2016-2017, from the same four elevations of the Southern Sierra Critical Zone Observatory that were used in previous research. In addition, they will collect shallow topsoil samples for comparison. They will then begin to describe the microbial community of the dust and soil from 2017, and to analyze the origin of dust entering the Sierra in the dry seasons of 2015, a dry year, and 2017, a wet year. The research will involve three graduate students and a postdoctoral scientist, as well as underserved minority undergraduates from both University of California (UC) Riverside and Merced, both Hispanic Serving Institutions. This project will be an excellent opportunity for educational and professional development. Additionally, the participating postdoctoral scientist takes part in a residential summer institute in Earth System Science for American Indian and Alaska Native high school students at UC Irvine. The research from this project will be disseminated during the summer institute in an effort to interest students in the interplay between climate and Earth surface processes. Dust has long been recognized as a vital source of nutrients in slowly eroding tropical ecosystems where intense weathering limits nutrient inputs from underlying bedrock. Investigators' recent work along an actively eroding montane landscape in the Sierra Nevada, California (CA) revealed large contributions of dust from both regional and transoceanic sources; growth-limiting nutrients (e.g., phosphorus) were determined to be supplied at rates on par with those from underlying bedrock weathering. This work also shows that microbial communities in dust varied between elevations, and community composition contained very few overlapping sequences with co-located soil communities. Also, the contributions from the Central Valley to mid-elevation sites increased substantially over the summer dry period, suggesting that the relative importance of regional dust sources to these ecosystems increases as the time since the last significant precipitation event increases. Analyses thus far have been based on dust inputs collected (2014) at the peak of the recent 2012-2016 drought, raising the question of whether findings are sensitive to changes in dust sources and emissions. The proposed work will begin to evaluate this question by analyzing the provenance and nutrients of dust collected during another drought-year summer (2015), and collecting new samples throughout the summer of 2017, after a wet year, with the goal of analyzing them in the near future.

调查人员表明，在干旱期间，灰尘对加利福尼亚山脉（CA）的内华达州的土壤很重要，并且它正在中央山谷（CA）和中国戈比沙漠（CA）进入塞拉山脉，并且两者都带来了高度营养的灰尘。这些结果基于对最近2012-2016干旱峰值的尘埃的分析，这提出了一个问题，即在潮湿的一年中是否会观察到相同的趋势。在这里，在2017年夏季，在2016-2017年潮湿的冬季之后，该团队将每月每月收集新的灰尘样品，从月份开始，从先前的研究中使用的南部塞拉山脉关键区观测站的四个高程。此外，它们将收集浅层表土样品以进行比较。然后，他们将从2017年开始描述灰尘和土壤的微生物群落，并分析2015年干旱季节，干燥的一年和2017年，尘埃进入山脉的起源，这是潮湿的一年。这项研究将涉及三名研究生和一名博士后科学家，以及来自加利福尼亚大学河滨大学和默塞德的服务不足的少数族裔本科生，都是西班牙裔服务机构。该项目将是教育和专业发展的绝佳机会。此外，参与的博士后科学家参加了UC Irvine的美洲印第安人和阿拉斯加本地高中生地球系统科学的住宅夏季研究所。该项目的研究将在夏季研究所期间传播，以使学生对气候和地面过程之间的相互作用感兴趣。长期以来，尘埃在缓慢侵蚀的热带生态系统中被认为是至关重要的养分来源，在这种生态系统中，强烈的风化限制了基础基岩的营养输入。调查人员最近在加利福尼亚州内华达州内华达州（CA）积极侵蚀的山地景观中的最新工作揭示了区域和跨科学来源的尘埃贡献。确定限制生长的养分（例如磷），以与基础基岩风化的养分相提并论。这项工作还表明，灰尘中的微生物群落在高程之间有所不同，社区组成几乎包含与共同建立的土壤群落的重叠序列。同样，在夏季干旱期间，从中央山谷到中期地点的贡献大大增加，这表明，随着上次重​​大降水事件的增加，区域尘埃源对这些生态系统的相对重要性增加。迄今为止的分析是基于收集的（2014年）在最近的2012 - 2016年干旱峰值上收集的（2014年），这提出了一个问题，即发现是否对尘埃源和排放的变化敏感。拟议的工作将通过分析在另一个夏季（2015年）（2015年）中收集的灰尘的出处和营养来评估这个问题，并在潮湿的一年中收集了整个2017年夏季的新样本，目的是在不久的将来分析它们。

项目成果

Microbiome interactions and their ecological implications at the Salton Sea

• DOI: 10.3733/ca.2022a0002
• 发表时间: 2022-04
• 期刊: California Agriculture
• 影响因子: 1.3
• 作者: Hannah L. Freund;M. Maltz;Mark P. Swenson;Talyssa M. Topacio;Vanessa A. Montellano;W. Porter;E. Aronson

Competing droughts affect dust delivery to Sierra Nevada

• DOI: 10.1016/j.aeolia.2019.100545
• 发表时间: 2019-12-01
• 期刊: AEOLIAN RESEARCH
• 影响因子: 3.3
• 作者: Aarons, S. M.;Arvin, L. J.;Aronson, E. L.
• 通讯作者: Aronson, E. L.