5. Conclusion

This study investigated the variation of soil attributes and microbial community composition along a land reclamation timeline. In the light of the results gathered in this study, it can be concluded that:
(1) The activities of soil enzymes such as urease, dehydrogenase and polyphenol oxidase increased with the time after reclamation, indicating that land reclamation can promote relevant soil ecosystem functions like N and P mineralization and soil respiration.
(2) The composition of the SMC varied across the reclamation timeline, reflecting changes in the soil attributes brought by land reclamation and/or by the current land practices.
(3) The SMCs and the Molecular Ecological Networks were more stable and less complex along the reclamation timeline, suggesting that land reclamation encourages the stability of the soil ecosystem, and that it thus has a positive impact on the soil.
However, we could not disentangle the effect of land reclamation on the studied key attributes. In particular, we could not verify whether some of the observed trends in the studied soil attributes were due to land reclamation or to the current land use practices. As a result, we animate future research striving to untwine the effect of land reclamation on the soil from that from farming or other land use practices taking place after reclamation. Yet, this study provided a new approach to study soil development through microbial network interactions in agricultural land, which is readily reproducible in studies seeking to evaluate the effect of land reclamation on the soil.