No abstract

Microbial phylogenetic diversity and species interactions in natural ecosystems have been investigated extensively, but our knowledge about their ecological roles, community dynamics and succession patterns is far from complete. This knowledge is essential to understand the complicated interactions of microorganisms in natural ecosystems. Here, an artificial ecosystem model of microorganisms was constructed from oil-well products and cultivated in a chemostat to investigate the succession pattern of alkane-degrading bacteria, a functional population in oil reservoirs. Their abundance was quantified by an improved qPCR technique. Our results showed that the phylogenetic structure of this artificial ecosystem model is stable during most of the chemostat cultivation process, while the genotype structure of alkane-degrading bacteria containing alkB genes shifted and their relative abundance oscillated similarly to a sinusoidal curve, like the succession pattern of producers in the Lotka-Volterra model. These results suggest that some theoretical frameworks of macroecology may work well in microbial ecosystems and be an efficient tool to understand them.

In collaborative innovation, personal relationships between boundary personnel of knowledge-intensive business service (KIBS) enterprises and organizational customers have a “double-edged sword” effect on inter-organizational relations. This study adopts the empirical research method based on KIBS enterprises’ cooperative innovation projects with organizational customers in China. Based on the theory of the inter-organizational relationship, this study explores the influence of personal relationships between employees at the boundary of enterprises on organizational customers’ opportunistic behavior. It analyzes the mediating effect of relationship governance and contract governance. The results show that personal relationships between boundary personnel will improve the probability of corporate customer opportunism. The relationship between governance and contract governance for enterprises can effectively restrain the opportunistic behavior of organizational customers. Further, the personal relationships between boundary personnel will enhance the relationship norms and inhibit the opportunistic behavior of organizational customers, and relationship governance plays a partial intermediary role in this. The personal relationships between employees at an enterprise’s boundary will relax the contract’s supervision and encourage corporate customer opportunism. Contract governance plays a partial intermediary role in this.