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

人类前往火星的使命预计将在21世纪30年代末进行。鉴于地球和火星之间的距离很远，确定可行的食物来源对成功的使命至关重要。然而，火星土壤中含有高氯酸盐，其浓度对大多数生命形式都是有毒的，包括植物和农作物。该项目的首要目标是探索开发和实施一种微生物催化的土壤生成过程，该过程可以从火星风化层中去除高氯酸盐，同时产生含有所需有机碳和无机养分的土壤，以支持植物生长和栽培。为了推进这一目标，项目团队建议研究如何通过选定的微生物财团调整火星土壤模拟物的生物风化，以产生可以支持火星上植物生长和作物种植的可行土壤。该项目的成功完成将通过产生基础知识和确定微生物联合体而造福社会，这些微生物联合体可以将火星风化层等无菌和有毒土壤转化为可维持植物生长和作物种植的有机和营养丰富的土壤。将通过教育和培训实现对社会的额外好处，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，研究火星风化层，或火星的表面物质，是无菌的含有高浓度的有毒高氯酸盐此外，火星风化层缺乏土壤有机质（SOM），这使得在火星上种植用于生物再生生命支持和粮食生产的植物极具挑战性。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，从火星风化层中产生有机和营养丰富的土壤。所提出的研究的指导假设是，选定的微生物财团的核心代谢过程可以进行调整，以耦合化学多样性和稳定的SOM的生产与微生物减少火星风化层中的高氯酸盐。研究的具体目标包括：1）在相关火星条件下，使用不饱和和饱和风化层模拟物，对选定的微生物财团还原高氯酸盐的程度和速率进行实验研究，2）表征SOM的组成和生物可利用的元素/使用高分辨率质谱法结合液相色谱法，从火星风化层模拟物的微生物风化中产生的营养物质，以及3）在火星风化层模拟物的微生物风化产生的土壤样品中证明了持续的种子萌发和植物生长。该项目的成功完成有可能通过产生基础知识和开发新方法产生变革性影响，使贫瘠和有毒土壤转化为有机和营养丰富的土壤，从而支持植物生长和作物种植。为了实施该项目的教育和推广活动，主要研究者（PI）建议制定和实施教师研究经验（RET）计划，以支持亚利桑那州州立大学（ASU）的八名高中教师的培训。此外，PI计划将这项研究的结果整合到各自机构的现有研究生/本科生课程和公共宣传活动中，包括亚利桑那州立大学的年度门户开放公共宣传活动和佛罗里达理工学院NPR附属站的STEM播客，重点关注与生物风化有关的主题，太空探索的微生物，以及火星风化层中的植物生长和作物种植。该项目由美国国家科学基金会、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知识价值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.