CAREER: Microbial controls on wetland carbon stabilization and storage

职业：湿地碳稳定和储存的微生物控制

• 批准号: 1845845
• 负责人: Ariane Peralta
• 金额: $ 59.39万
• 依托单位: East Carolina University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1845845&HistoricalAwards=false
• 关键词: CAREER; Microbial; controls; wetland; carbon

---------------------------------------------------------------------------------------While wetlands only occupy about 7% of Earth's land surface, they are estimated to hold about 40% of its carbon (C). Wetlands are effective at storing C due to their high rates of vegetation growth and generally low rates of soil C losses from decomposition by microbes. Like many ecosystems, wetlands are subjected to nutrient enrichment via fertilization from agricultural runoff. Often, fertilization effects can increase microbial activity, leading to higher rates of C loss through microbial decomposition. Thus, wetland C storage is vulnerable to changes in the environment, which, in turn, can result in a reduced capacity for wetlands to compensate for change. Wetland C storage potential could be overestimated when impacts of nutrient enrichment and microbial physiology are not incorporated into the earth-system context. This research will provide insights into microbial controls on soil C processes, which have implications for broad national interests in energy, natural resources management and conservation. This research will advance the fields of ecosystem science, ecology, and microbiology by examining the relationships among microbial diversity, microbial metabolisms, and C-cycling functions. It will also benefit society through classroom educational content focused on microbial diversity and processes at the K-12, undergraduate and graduate levels that will reach under-served populations, enhancing diversity of the STEM workforce. This study will test the hypothesis that inorganic nutrient enrichment causes shifts in microbial communities from slow growing oligotroph- to fast growing copiotroph-dominated assemblages, resulting in changes in microbial processing of C and nutrients in soils. An altered ecosystem may lead to soil organic matter (SOM) destabilization, due to decreased mineral-protected SOM and increased respiration rates, thereby reducing soil C storage in wetlands. The specific objectives of this project include: (1) determine how variation in above- and below-ground plant biomass relates to SOM buildup in a historically nutrient-poor wetland now experiencing nutrient enrichment; (2) relate microbial resource-use strategies to atmospheric gas exchange (methane, carbon dioxide), and soil organic matter pools under ambient and nutrient-enriched conditions; and (3) examine how shifts in microbial biomass, community structure, and metabolic diversity affect SOM stabilization and C storage potential due to long-term fertilization. Since 2003, replicated fertilization and disturbance (by mowing) treatments have been applied to a nutrient-poor wetland ecosystem in the North Carolina coastal plain. This new project will leverage the field experiment to determine whether ongoing fertilization influences plant-microbe relationships and soil C storage potential. If nutrient enrichment disrupts wetland C storage, then predictions for wetland C pools may be overestimated since wetlands experience both human and temperature-induced nutrient enrichment. This study will also determine whether physiological assessments of microbial communities (used to characterize oligotrophic and copiotrophic taxa) provide a better predictor of ecosystem responses than taxonomy or biomass-based metrics.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.

- -湿地在储存碳方面是有效的，因为它们的植被生长率高，而微生物分解造成的土壤碳损失率一般较低。像许多生态系统一样，湿地通过农业径流的施肥进行营养富集。通常，施肥效应可以增加微生物活性，导致通过微生物分解的更高的C损失率。因此，湿地碳储量容易受到环境变化的影响，这反过来又会导致湿地补偿变化的能力降低。湿地碳储存潜力可能被高估时，营养富集和微生物生理的影响，不纳入地球系统的背景下。这项研究将为微生物控制土壤碳过程提供见解，这对能源，自然资源管理和保护方面的广泛国家利益具有影响。本研究将通过研究微生物多样性、微生物代谢和碳循环功能之间的关系，推动生态系统科学、生态学和微生物学领域的发展。它还将通过重点关注K-12，本科生和研究生水平的微生物多样性和过程的课堂教育内容造福社会，这些内容将覆盖服务不足的人群，增强STEM劳动力的多样性。这项研究将测试的假设，无机营养富集导致微生物群落从缓慢增长的寡养型快速增长的共生为主的组合，导致微生物处理的C和土壤中的养分的变化。改变的生态系统可能会导致土壤有机质（SOM）不稳定，由于减少矿物保护的SOM和呼吸速率增加，从而减少土壤C储存在湿地。本项目的具体目标包括：（1）确定在一个历史上营养贫乏的湿地中，地上和地下植物生物量的变化与有机质积累的关系;（2）将微生物资源利用策略与大气气体交换联系起来（甲烷、二氧化碳）和土壤有机物库;以及（3）研究长期施肥导致的微生物生物量、群落结构和代谢多样性的变化如何影响SOM稳定性和C储存潜力。自2003年以来，复制施肥和干扰（割草）治疗已被应用到营养贫乏的湿地生态系统在北卡罗来纳州沿海平原。这个新项目将利用田间试验来确定持续施肥是否会影响植物-微生物关系和土壤碳储存潜力。如果养分富集破坏湿地碳存储，那么预测湿地碳库可能会被高估，因为湿地经历人类和温度引起的养分富集。这项研究还将确定是否微生物群落的生理评估（用于表征寡养和共养类群）提供了一个更好的预测生态系统的反应比分类学或生物量为基础的metrics.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

Mud in the city: Effects of freshwater salinization on inland urban wetland nitrogen and phosphorus availability and export

• DOI: 10.1002/lol2.10273
• 发表时间: 2022-08
• 期刊: Limnology and Oceanography Letters
• 影响因子: 7.8
• 作者: Lauren E. Kinsman-Costello;E. Bean;Audrey Goeckner;Jeffrey W. Matthews;M. O’Driscoll;M. Palta;A. Peralta;A. J. Reisinger;Gabriela Reyes;A. Smyth;Marie L. Stofan

Distinct microbial communities alter litter decomposition rates in a fertilized coastal plain wetland

• DOI: 10.1002/ecs2.3619
• 发表时间: 2021-06
• 期刊: Ecosphere
• 影响因子: 2.7
• 作者: Megan E. Koceja;Regina B. Bledsoe;C. Goodwillie;A. Peralta

Long-Term Nutrient Enrichment of an Oligotroph-Dominated Wetland Increases Bacterial Diversity in Bulk Soils and Plant Rhizospheres

• DOI: 10.1128/msphere.00035-20
• 发表时间: 2020-05-01
• 期刊: MSPHERE
• 影响因子: 4.8
• 作者: Bledsoe, Regina B.;Goodwillie, Carol;Peralta, Ariane L.
• 通讯作者: Peralta, Ariane L.