Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic
Discussion papers
https://doi.org/10.5194/bg-2019-41
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-2019-41
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Reviews and syntheses 18 Feb 2019

Reviews and syntheses | 18 Feb 2019

Review status
This discussion paper is a preprint. A revision of the manuscript is under review for the journal Biogeosciences (BG).

Biological weathering and its consequences at different spatial levels – from nanoscale to global scale

Roger D. Finlay1, Shahid Mahmood1, Nicholas Rosenstock2, Emile B. Bolou-Bi3, Stephan J. Köhler4, Zaenab Fahad1,5, Anna Rosling5, Håkan Wallander2, Salim Belyazid6, Kevin Bishop4, and Bin Lian7 Roger D. Finlay et al.
  • 1Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
  • 2Department of Biology, Lund University, Box 117, 221 00 Lund, Sweden
  • 3Université Felix Houphouët-Boigny, UFR des Sciences de la Terre et des Ressources Minières, Departement des Sciences du sol, BP 582 Abidjan 22, Côte D’Ivoire
  • 4Soil-Water-Environment Center, Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
  • 5Department of Ecology and Genetics, EBC, Uppsala University 752 36 Uppsala, Sweden
  • 6Department of Physical Geography, Stockholm University, 106 91 Stockholm, Sweden
  • 7Laboratory College of Life Sciences, Nanjing Normal University, Nanjing 210023, China

Abstract. Plant nutrients can be recycled through microbial decomposition of organic matter but replacement of base cations and phosphorus, lost through harvesting of biomass/biofuels or leaching, requires de novo supply of fresh nutrients released through weathering of soil parent material (minerals and rocks). Weathering involves physical and chemical processes that are modified by biological activity of plants, microorganisms and animals. This article reviews recent progress made in understanding biological processes contributing to weathering. A perspective of increasing spatial scale is adopted, examining the consequences of biological activity for weathering from nanoscale interactions, through in vitro and in planta microcosm and mesocosm studies, to field experiments and finally, ecosystem and global level effects. The topics discussed include: the physical alteration of minerals and mineral surfaces, the composition, amounts, chemical properties and effects of plant and microbial secretions, and the role of carbon flow (including stabilization/sequestration of C in organic and inorganic forms). Although the predominant focus is on the effects of fungi in forest ecosystems, the properties of biofilms, including bacterial interactions, are discussed. The implications of these biological processes for modelling are discussed and finally, we attempt to identify some key questions and knowledge gaps, as well as experimental approaches and areas of research in which future studies are likely to yield useful results. A particular focus of this article is to improve the representation of the ways in which biological processes complement physical and chemical processes that mobilize mineral elements, making them available for plant uptake. This is necessary to produce better estimates of weathering that are necessary for sustainable management of forests in a post-fossil fuel economy. While there are abundant examples of nm- and µm-scale physical interactions between microorganisms and different minerals, opinion appears to be divided with respect to the quantitative significance of these observations to overall weathering. Numerous in vitro experiments and microcosm studies involving plants and their associated microorganisms suggest that the allocation of plant-derived carbon, mineral dissolution and plant nutrient status are tightly coupled but there is still disagreement about the extent to which these processes contribute to field-scale observations. Apart from providing dynamically responsive pathways for the allocation of plant-derived carbon to power dissolution of minerals, mycorrhizal mycelia provide conduits for the long-distance transportation of weathering products back to plants that are also quantitatively significant sinks for released nutrients. These mycelial pathways bridge heterogeneous substrates, reducing the influence of local variation in C : N ratios. The production of polysaccharide matrices by biofilms of interacting bacteria and/or fungi at interfaces with mineral surfaces and roots, influences patterns of production of antibiotics and quorum sensing molecules, with concomitant effects on microbial community structure, and the qualitative and quantitative composition of mineral solubilizing compounds and weathering products. Patterns of carbon allocation and nutrient mobilization from both organic and inorganic substrates have been studied at larger spatial and temporal scales, including both ecosystem and global levels and there is a generally wider degree of acceptance of the "systemic" effects of microorganisms on patterns of nutrient mobilization. Theories about the evolutionary development of weathering processes have been advanced but there is still a lack of information connecting processes at different spatial scales and detailed studies of the liquid chemistry of local weathering sites at the µm-scale, together with up-scaling to soil-scale dissolution rates, are advocated, as well as new approaches involving stable isotopes.

Roger D. Finlay et al.
Interactive discussion
Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Roger D. Finlay et al.
Roger D. Finlay et al.
Viewed  
Total article views: 376 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
274 99 3 376 1 0
  • HTML: 274
  • PDF: 99
  • XML: 3
  • Total: 376
  • BibTeX: 1
  • EndNote: 0
Views and downloads (calculated since 18 Feb 2019)
Cumulative views and downloads (calculated since 18 Feb 2019)
Viewed (geographical distribution)  
Total article views: 300 (including HTML, PDF, and XML) Thereof 298 with geography defined and 2 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 15 Jun 2019
Publications Copernicus
Download
Short summary
Effects of biological activity on mineral weathering operate at scales ranging from short-term, microscopic interactions to global, evolutionary time-scale processes. Microorganisms have had well-documented effects at large spatio-temporal scales but to establish the quantitative significance of microscopic measurements to field-scale processes, higher-resolution studies of liquid chemistry at local weathering sites and improved up-scaling to soil-scale dissolution rates are still required.
Effects of biological activity on mineral weathering operate at scales ranging from short-term,...
Citation