EFRI ELiS: Bioweathering dynamics and ecophysiology of microbially catalyzed soil genesis of Martian regolith

人类登上火星的任务预计将在本世纪30年代末进行。考虑到地球和火星之间的巨大距离，确定可行的食物来源对于任务的成功至关重要。然而，火星土壤中含有的高氯酸盐浓度对包括植物和农作物在内的大多数生命形式都是有毒的。该项目的总体目标是探索开发和实施微生物催化的土壤发生过程，该过程可以从火星风土层中去除高氯酸盐，同时产生含有支持植物生长和栽培所需的有机碳和无机营养的土壤。为了推进这一目标，项目组建议研究如何调整选定微生物联盟对火星土壤模拟物的生物风化，以产生能够支持火星上植物生长和作物种植的可行土壤。这一项目的成功完成将使社会受益，因为它将产生基础知识，并确定可以将火星风化层等贫瘠和有毒的土壤转化为能够维持植物生长和作物种植的有机和营养丰富的土壤的微生物协会。还将通过教育和培训为社会带来更多好处，包括指导亚利桑那州立大学的一名博士后研究员、一名研究生和两名本科生，佛罗里达理工学院的一名研究生和一名本科生，以及亚利桑那大学的一名研究生。火星表层材料是无菌的，含有高浓度的有毒高氯酸盐。此外，火星表层缺乏土壤有机质(SOM)，这使得火星上用于生物再生生命支持和食物生产的植物栽培具有极大的挑战性。该项目的目标是设计和开发可扩展的微生物技术和解决方案，以从火星风土层中产生有机和营养丰富的土壤。拟议研究的指导性假设是，可以调整选定微生物联合体的核心代谢过程，以将化学上多样化和稳定的SOM的产生与火星风暴层中高氯酸盐的微生物还原相结合。这项研究的具体目标包括：1)使用不饱和和饱和风化层模拟物，在相关火星条件下，对选定的微生物群落还原高氯酸盐的程度和速率进行实验研究；2)利用高分辨率质谱仪与高效液相联用，表征土壤有机质的组成和微生物风化火星风化物产生的生物可利用元素/养分；以及3)展示火星风化物微生物风化产生的土壤样品中持续种子萌发和植物生长。这一项目的成功完成有可能产生变革性的影响，通过产生基本知识和开发新的方法，将贫瘠和有毒的土壤转化为可支持植物生长和作物种植的有机和营养丰富的土壤。为了实施该项目的教育和外展活动，首席调查员(PI)建议制定和实施教师研究经验(RET)计划，以支持亚利桑那州立大学(ASU)对8名高中教师的培训。此外，PIS计划将这项研究的结果纳入各自机构现有的研究生/本科生课程和公共外联活动，包括每年在亚利桑那州立大学的开放式公共外联活动和佛罗里达理工学院NPR附属站的STEM播客，重点是与生物收集、用于空间探索的微生物以及火星表层植物生长和作物种植有关的主题。该项目由国家科学基金会、新兴前沿和多学科活动办公室(EFMA)和美国国家航空航天局(NASA)联合赞助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A human mission to Mars is projected to take place by the late 2030s. Identifying viable sources of food will be critical to a successful mission given the significant distance between Earth and Mars. However, the Martian soil contains perchlorate salts at concentrations that are toxic to most forms of life including plants and crops. The overarching goal of this project is to explore the development and implementation of a microbially catalyzed soil genesis process that could remove perchlorate from Martian regolith while producing a soil containing the required organic carbon and inorganic nutrients to support plant growth and cultivation. To advance this goal, the project team proposes to investigate how to tune the bioweathering of Martian soil simulants by selected microbial consortia to generate viable soils that could support plant growth and crop cultivation on Mars. The successful completion of this project will benefit society through the generation of fundamental knowledge and the identification of microbial consortia that could convert sterile and toxic soils, such as the Martian regolith, to organic and nutrient rich soils that can sustain plant growth and crop cultivation. Additional benefits to society will be achieved through education and training including the mentoring of one postdoctoral researcher, one graduate student, and two undergraduate students at Arizona State University, one graduate student and one undergraduate student at the Florida Institute of Technology, and one graduate student at the University of Arizona.Mars regolith, or the surface material of Mars, is sterile with high concentrations of toxic perchlorate salts. In addition, the Mars regolith is devoid of soil organic matter (SOM) making plant cultivation for bio-regenerative life support and food production on Mars extremely challenging. The goal of this project is to design and develop scalable microbiological technologies and solutions to generate an organic and nutrient rich soil from Martian regolith. The guiding hypothesis of the proposed research is that the core metabolic processes of selected microbial consortia can be tuned to couple the production of a chemically diverse and stable SOM with the microbial reduction of perchlorate salts in Martian regolith. The specific objectives of the research include 1) experimental investigations of the extents and rates of perchlorate reduction by the selected microbial consortia under relevant Mars conditions using unsaturated and saturated regolith simulants, 2) characterization of the composition of the SOM and the bioavailable elements/nutrients that are generated from the microbial weathering of Mars regolith simulants using high resolution mass spectrometry coupled with liquid chromatography, and 3) demonstration of sustained seed germination and plant growth in the soil samples generated from the microbial weathering of Martian regolith simulants. The successful completion of this project has the potential for transformative impact through the generation of fundamental knowledge and the development of new methods to enable the conversion of sterile and toxic soils to organic and nutrient rich soils that could support plant growth and crop cultivation. To implement the education and outreach activities of the project, the Principal Investigators (PIs) propose to develop and implement a Research Experience for Teachers (RET) program to support the training of eight high school teachers at Arizona State University (ASU). In addition, the PIs plan to integrate the findings from this research into existing graduate/undergraduate courses and public outreach activities at their respective institutions including a yearly Open Door public outreach event at ASU and STEM podcasts of the Florida Institute of Technology NPR affiliate station with a focus on topics related to bioweathering, microorganisms for space exploration, and plant growth and crop cultivation in Martian regolith. This project is jointly sponsored by the National Science Foundation, Office of Emerging Frontiers and Multidisciplinary Activities (EFMA) and the National Aeronautics and Space Administration (NASA).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.