Effects of organic matter manipulation on archaeal, bacterial, and fungal community assembly

Community assembly is not only important for community structure, it is also a strong predictor of ecosystem functioning. Understanding how communities initially form and colonize lake sediments where essential functions like carbon cycling occur is therefore important for whole-ecosystem processes. Here, we tested for the deterministic processes that drive assembly order. Is this order primarily determined by the sediment or by the lake conditions ? What influences how rapidly this environmental filtering occurs? Do communities become more interconnected with time because of the sediment or lake conditions? Artificial mesocosms were created with varying levels and types of terrestrial organic matter. The mesocosms were placed at the bottom of three lakes. We sampled the sediment monthly over a two-month period to characterize microbial communities.

群落组装不仅对群落结构至关重要，而且是对生态系统功能具有强大预测力的关键因素。因此，理解群落如何最初形成并侵占湖泊沉积物（其中碳循环等基本功能得以发生）对于整个生态系统过程至关重要。在本研究中，我们测试了驱动组装顺序的确定性过程。这一顺序是否主要由沉积物或湖泊条件所决定？是什么影响了这一环境筛选过程的速度？是否由于沉积物或湖泊条件的影响，群落随着时间的推移而变得更加相互关联？我们构建了包含不同水平和类型的陆地有机物的模拟生态系统。这些模拟生态系统被放置在三个湖泊的底部。在两个月的时间内，我们每月对沉积物进行采样，以表征微生物群落。