RESPONSES OF TOTAL AND ACTIVE SOIL MICROBIAL COMMUNITIES TO CLIMATE WARMING

• Main Author: Feng, Jiajie
• Other Authors: Zhou, Jizhong, Liu, Shaorong, McCarthy, Heather R., Krumholz, Lee R., Stevenson, Bradley S.
• Language: English
• Published: 2019
• Subjects: Biology; Microbiology; Ecology; Environmental Sciences; permafrost; Tundra
• Online Access: https://hdl.handle.net/11244/322860

As illustrated by accumulating scientific evidence, unconscionable anthropogenic activities since industrialization such as intensive land utilization and accumulation of various greenhouse gases due to fossil fuel combustion have caused global climate warming, which has in turn caused instability of the earth’s ecosystems and impacts on human society. Granted that huge efforts through scientific research have been devoted to address the interactions between the biosphere and the warmer climate, there are still numerous understudied scientific areas and questions of this topic due to the complicacy of both the biosphere and the climate system. Microbial communities are the most abundant, diverse and complex assemblages in the biosphere, and play crucial roles in geochemical processes closely related to climate warming. However, due to the difficulties in observing and cultivating the microorganisms, responses and feedbacks of microbial communities to climate warming are difficult to observe and predict, in terms of microbial taxonomic, functional and interactional patterns under warming. High-throughput genomic technologies have revolutionized microbial ecology. Such technologies are capable to provide detailed characterization and thus great insight into studies of complex and uncultivated microbial communities and the microbially-mediated mechanisms governing the carbon balance under a warmer climate. Using several such high-throughput genomic technologies, this dissertation attempts to assess responses of soil microbial community to warming, based on field experiments and laboratory incubations. The high-latitude permafrost region (tundra) could be a “hot spot” in global carbon balance and the changing climate because it possesses the largest carbon reservoir globally. This dissertation focuses on the tundra regions and the residing microbial communities, while tall-grass prairie (temperate grassland), an understudied but important ecosystem type among the terrestrial ecosystems, should also be studied and ...