## 4 Discussion
Table S2.2: FAPROTAX validation of prokaryotic taxa prokaryotic taxa detected in forest soil showing evident based on peer-reviewed literature of soil ecosystems on the appearance and the functional performance of prokaryotic taxa detected in forest soil. Table S2.3: FAPROTAX validation of prokaryotic taxa prokaryotic taxa detected in mangrove rhizosphere soil showing evident based on peer-reviewed literature of soil ecosystems on the appearance and the functional performance of prokaryotic taxa detected in mangrove rhizosphere soil. Table S3: Data from peer-reviewed publications showing sample sources and proportion of number of OTUs assigned by FAPROTAX to total detected OTUs. Table S4: Example of data from FAPROTAX database showing functions, prokaryotic taxa and their habitat obtained from the reference cited in FAPROTAX database. Conceptualization, T.D., T.W. and W.P. ; field experiments, C.S., S.F.M.W., T.D. and W.P. ; molecular analysis, C.S., S.F.M.W., S.H. and W.P. ; bioinformatics, S.F.M.W. and T.W. ; software, S.F.M.W. and T.W. ; formal analysis, C.S., S.H. and W.P. ; investigation, C.S., S.F.M.W., S.H. and W.P. ; resources, T.D. and W.P. ; data curation, C.S., S.H. and W.P. ; writing--original draft preparation, C.S., W.P. and T.D. ; writing--review and editing, C.S., S.F.M.W., S.H., T.D., T.W. and W.P. ; visualization, C.S. and W.P. ; supervision, W.P. and T.D. ; funding acquisition, W.P. and T.D. All authors have read and agreed to the published version of the manuscript. **Funding:** The next generation sequencing cost was covered by personal research budgets of [PERSON] from the Helmholtz Centre for Environmental Research--UFZ. **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** Publicly available datasets were analyzed in this study. This data can be found under BioProject accession number: PRJNA646011 and PRJNA554586. **Acknowledgments:** We appreciate the Helmholtz Association, the Federal Ministry of Education and Research, the State Ministry of Science and Economy of Saxony-Anhalt, and the State Ministry for Higher Education, Research and the Arts Saxony to fund the Global Change Experimental Facility (GCEF) project. We thank to [PERSON] for his role in setting up and maintaining the GCEF project and the staffs of the Bad Lauchstadt Experimental Research Station for their work in maintaining the plots and infrastructures of the GCEF. [PERSON] and [PERSON] are thanks for helping with field experiments and molecular works. We also thank to Forest Restoration Research Unit (FORRU-CMU) for their support on field experiment in Thailand. C.S. thanks to Science Achievement Scholarship of Thailand for financial support. S.F.M.W. is supported financially by the Egyptian Scholarship (Ministry of Higher Education, External Missions 2016/2017 call). T.D. is partially supported by Chiang Mai University. **Conflicts of Interest:** The authors declare no conflict of interest. Appendix A Functional Phenotypes Derived from Tax4 Fun and FAPROTAX. A Simulate Result from Bacterial Communities of Agricultural Rhizosphere of _Trifolium pretense_  
A dataset (OTU table) consisted of bacterial communities in the rhizosphere of _Trifolium prtense_ was selected to simulate the result derived from Tax4 Fun. In detail, the Tax4 Fun [8] R package, which employs 16S rRNA gene-based taxonomic information, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database were used to predict the metabolic functional attributes of bacterial communities in the rhizosphere of _T. prtense_. Tax4 Fun converted the SILVA-labelled OTUs into prokaryotic KEGG organisms and normalized these predictions using the 16S rRNA copy number (obtained from the National Center for Biotechnology Information genome annotations).