阐明决定微生物群落结构的细菌和真菌之间的复杂相互作用,composition,并在土壤中发挥作用,以及调节碳(C)和营养通量,对理解生物地球化学循环至关重要。在各种互动中,资源竞争是决定土壤中这两个大微生物群适应和生态位分化的主要因素。这是因为微生物生长的C和能量限制是规则而不是例外。这里,我们回顾了细菌和真菌——土壤中的两个主要王国——对这些和其他资源的竞争机制,导致生态位分化,以及全球变化对这场竞争的影响。标准化的微生物利用偏好表明,细菌在吸收简单有机化合物作为底物方面的效率是1.4-5倍,而真菌在利用复杂化合物方面的效率是其1.1-4.1倍。因此,细菌在简单的底物上强烈胜过真菌,而真菌利用复杂的化合物。细菌还与真菌竞争在复杂底物降解期间释放的产物。基于这些细节,我们区分了空间,temporal,和土壤中这两组的化学生态位。在主要的五大全球变化下,包括二氧化碳、氮沉积、土壤酸化,全球变暖,和干旱。二氧化碳,氮沉积升高,变暖增加了细菌的优势,而土壤酸化和干旱增加了真菌竞争力。
Elucidating complex interactions between bacteria and fungi that determine microbial community structure, composition, and functions in soil, as well as regulate carbon (C) and nutrient fluxes, is crucial to understand biogeochemical cycles. Among the various interactions, competition for resources is the main factor determining the adaptation and niche differentiation between these two big microbial groups in soil. This is because C and energy limitations for microbial growth are a rule rather than an exception. Here, we review the C and energy demands of bacteria and fungi-the two major kingdoms in soil-the mechanisms of their competition for these and other resources, leading to niche differentiation, and the global change impacts on this competition. The normalized microbial utilization preference showed that bacteria are 1.4-5 times more efficient in the uptake of simple organic compounds as substrates, whereas fungi are 1.1-4.1 times more effective in utilizing complex compounds. Accordingly, bacteria strongly outcompete fungi for simple substrates, while fungi take advantage of complex compounds. Bacteria also compete with fungi for the products released during the degradation of complex substrates. Based on these specifics, we differentiated spatial, temporal, and chemical niches for these two groups in soil. The competition will increase under the main five global changes including elevated CO2, N deposition, soil acidification, global warming, and drought. Elevated CO2, N deposition, and warming increase bacterial dominance, whereas soil acidification and drought increase fungal competitiveness.