环境科学
土壤水分
产甲烷
牧场
含水量
微观世界
物种均匀度
甲烷
农学
生态学
环境化学
土壤科学
生物
化学
物种多样性
地质学
岩土工程
作者
Andressa Monteiro Venturini,Naíssa Maria Silvestre Dias,Júlia Brandão Gontijo,Caio Augusto Yoshiura,Fabiana da Silva Paula,Kyle Meyer,Fernanda Mancini Nakamura,Aline Giovana da França,Clóvis Daniel Borges,Jos Barlow,Erika Berenguer,Klaus Nüsslein,Jorge L. Mazza Rodrigues,B. J. M. Bohannan,Siu Mui Tsai
标识
DOI:10.1016/j.envres.2022.113139
摘要
Climatic changes are altering precipitation patterns in the Amazon and may influence soil methane (CH4) fluxes due to the differential responses of methanogenic and methanotrophic microorganisms. However, it remains unclear if these climate feedbacks can amplify land-use-related impacts on the CH4 cycle. To better predict the responses of soil CH4-cycling microorganisms and emissions under altered moisture levels in the Eastern Brazilian Amazon, we performed a 30-day microcosm experiment manipulating the moisture content (original moisture; 60%, 80%, and 100% of field capacity - FC) of forest and pasture soils. Gas samples were collected periodically for gas chromatography analysis, and methanogenic archaeal and methanotrophic bacterial communities were assessed using quantitative PCR and metagenomics. Positive and negative daily CH4 fluxes were observed for forest and pasture, indicating that these soils can act as both CH4 sources and sinks. Cumulative emissions and the abundance of methanogenesis-related genes and taxonomic groups were affected by land use, moisture, and their interaction. Pasture soils at 100% FC had the highest abundance of methanogens and CH4 emissions, 22 times higher than forest soils under the same treatment. Higher ratios of methanogens to methanotrophs were found in pasture than in forest soils, even at field capacity conditions. Land use and moisture were significant factors influencing the composition of methanogenic and methanotrophic communities. The diversity and evenness of methanogens did not change throughout the experiment. In contrast, methanotrophs exhibited the highest diversity and evenness in pasture soils at 100% FC. Taken together, our results suggest that increased moisture exacerbates soil CH4 emissions and microbial responses driven by land-use change in the Amazon. This is the first report on the microbial CH4 cycle in Amazonian upland soils that combined one-month gas measurements with advanced molecular methods.
科研通智能强力驱动
Strongly Powered by AbleSci AI