References

Importance of Microorganisms for Soil Aggregation 115
5
Conclusion
A large number of papers are devoted to characterizing and understanding
the aggregate formation–stabilization processes. Most of the papers concern
the nature of the microbiological factors. They support the role, over
and over again, of soil microorganisms. They emphasize the interactions
between these microbial factors in aggregation and reveal the importance
of complex systems with more than one agent and one process:
– bacteria versus fungi biomass,
– the growth of fungi and their dependence on roots and plant debris
for their energy source,
– the importance of fungal and bacterial metabolites and exudates in
adsorptive reactions with mineral particles,
– the distribution of these metabolites through the soil pore systems
It is all an energy-driven process. Therefore, any strategy aims at improving
the impact of soil microorganism on soil structure should take into account
the allocation of carbon inputs that fuel these biological processes.
Acknowledgements. The author expresses his gratitude to Dr M. Oades for
his helpful comments
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