Nitrogen use aggravates bacterial diversity and network complexity responses to temperature

Abstract

Rising temperature affects microbial composition and function in agriculture field, especially under nitrogen fertilization. In this study, we investigated the bacterial community of paddy soil incubated at controlled temperatures (5 °C, 15 °C, 25 °C, and 35 °C). Results showed that the response of bacterial communities to temperature was not uniform. Temperature elevation from 15 to 25 °C abruptly shifted the soil bacterial community, whereas elevation from 5 to 15 °C and from 25 to 35 °C had a marginal effect. The bacterial α-diversity was higher at 5 °C and 15 °C, owing to the massively distributed taxa with low abundance. However, as the temperature increased to 25 °C and 35 °C, these taxa were diminished, whereas Firmicutes significantly increased, resulting in a strong decline in α-diversity. Simultaneously, bacterial network complexity significantly increased at 25 °C and 35 °C, indicating the bacteria had closer interactions. Nitrogen application aggravated the variation in bacterial diversity and network complexity among temperatures. Interestingly, most complex network was observed under higher temperatures in fertilized soils. Collectively, these results indicate that nitrogen exacerbates the response of the soil bacterial community to temperature, and association between diversity and network complexity may be present.

Differentiated responses of the phyllosphere bacterial community of the yellowhorn tree to precipitation and temperature regimes across Northern China

“…Another study also found that climatic factors could indirectly impact the composition of phyllosphere bacterial community by modulating bacterial interactions (Li et al, 2022c). It is almost certain that local changes in climate could have an impact on the ecosystem functioning of the phyllosphere microbiome given the narrow climatic endurance of its key microbial taxa (Xing et al, 2022). Besides, the links and nodes of the phyllosphere bacterial community networks from yellowhorn had positive and negative correlative relationships with the temperature and precipitation variables, respectively.…”

“…Work (Li et al, 2022c) also demonstrated that less precipitation could strengthen the interactions and cooperation between co-occurring microbial functional taxa, possibly due to greater bacterial separation and reduced competition between bacterial species under conditions of little precipitation (Treves et al, 2003). Previous studies also affirmed that appropriately higher temperatures could intensify both the network connectivity and complexity of microbial communities to improve the cooperation between member microbes to defend the impaired ecosystem functions (Yuan et al, 2021;Xing et al, 2022). Therefore, combining climatic factors and key microbial interactions could reinforce the regulation of phyllosphere bacterial community assembly on yellowhorn hosts.…”

Ocean acidification alters the benthic biofilm communities in intertidal soft sediments

“…All networks were visualized in Gephi software, and topological features of each network were also calculated in Gephi, including number of network nodes, number of edges, number of positive and negative correlations, average degree, network density, network diameter, network density, modularity, and average clustering coefficient. The details of network analyses referred to Xing et al (2022). Two functional prediction tools (PICRUST2 and FAPROTAX) were used to analyze the effects of OA on the functional potentials of microbial biofilms.…”

“…Network density is defined as the fraction of edges present over all possible edges in the network. Both two parameters describe the connectivity of a network (Xing et al, 2022).…”

“…For the biotic networks in muds, OA increased the number of edges (i.e., interactions), average degree and network density, suggesting a more connected biotic network in acidifying sediments. This increased connectivity of network is regarded as compensation for the decreased biodiversity under high CO 2 conditions, helping to maintain the essential ecosystem functions (Xing et al, 2022).…”