Hawkesbury Institute for the Environment, University of Western Sydney, Penrith South, New South Wales, Australia.
Appl Environ Microbiol. 2013 Jul;79(13):4031-40. doi: 10.1128/AEM.00095-13. Epub 2013 Apr 26.
Microbes play an essential role in ecosystem functions, including carrying out biogeochemical cycles, but are currently considered a black box in predictive models and all global biodiversity debates. This is due to (i) perceived temporal and spatial variations in microbial communities and (ii) lack of ecological theory explaining how microbes regulate ecosystem functions. Providing evidence of the microbial regulation of biogeochemical cycles is key for predicting ecosystem functions, including greenhouse gas fluxes, under current and future climate scenarios. Using functional measures, stable-isotope probing, and molecular methods, we show that microbial (community diversity and function) response to land use change is stable over time. We investigated the change in net methane flux and associated microbial communities due to afforestation of bog, grassland, and moorland. Afforestation resulted in the stable and consistent enhancement in sink of atmospheric methane at all sites. This change in function was linked to a niche-specific separation of microbial communities (methanotrophs). The results suggest that ecological theories developed for macroecology may explain the microbial regulation of the methane cycle. Our findings provide support for the explicit consideration of microbial data in ecosystem/climate models to improve predictions of biogeochemical cycles.
微生物在生态系统功能中发挥着至关重要的作用，包括进行生物地球化学循环，但目前在预测模型和所有全球生物多样性辩论中被视为一个黑匣子。这是由于（i）微生物群落的时空变化被认为是不可预测的，以及（ii）缺乏解释微生物如何调节生态系统功能的生态理论。提供微生物调节生物地球化学循环的证据对于预测生态系统功能至关重要，包括在当前和未来气候情景下的温室气体通量。使用功能措施、稳定同位素示踪和分子方法，我们表明，微生物（群落多样性和功能）对土地利用变化的响应是稳定的。我们调查了由于沼泽、草原和荒地造林而导致的净甲烷通量和相关微生物群落的变化。造林导致所有地点大气甲烷汇的稳定和一致增强。这种功能的变化与微生物群落（甲烷营养菌）的特定生态位分离有关。研究结果表明，为宏观生态学开发的生态理论可能解释了微生物对甲烷循环的调节。我们的研究结果为在生态系统/气候模型中明确考虑微生物数据以改善生物地球化学循环预测提供了支持。
