The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Daniel Conley

Daniel Conley

Professor

Daniel Conley

Pedogenic and biogenic alkaline-extracted silicon distributions along a temperate land-use gradient

Author

  • L. Barao
  • Wim Clymans
  • F. Vandevenne
  • P. Meire
  • Daniel Conley
  • E. Struyf

Summary, in English

The primary source of dissolved silicon (Si: DSi) is the weathering of silicate minerals. In recent years, it has been shown that Si cycling through vegetation creates a more soluble Si pool in the soil, as amorphous Si (ASi) deposits in plants (phytoliths) are returned to the soil through litter. Amorphous Si accumulation in soils depends on a number of factors, including land use. In addition to the biogenic ASi fraction, soils contain other non-biogenic amorphous and sorbed Si fractions that could contribute significantly to DSi export to rivers, but hitherto these Si fractions have been difficult to separate from each other with traditionally applied extraction methods. The objective of this paper is to understand better how land use affects the distribution of the different extractable Si fractions. We re-analysed samples from the land-use gradient studied previously by Clymans et al. () with a continuous Si and aluminium (Al) extraction technique. Different extractable Si fractions of biogenic or pedogenic origin were successfully separated on the basis of their dissolution in alkaline solutions (Na2CO3 and NaOH) and Si:Al ratios. We show that forests store almost all alkaline extractable Si (AlkExSi) in the pedogenic fraction while the importance of phytoliths increases with human disturbance to become the dominant fraction in the AlkExSi pool at the arable site. The pedogenic AlkExSi pool is also more reactive than the phytolith-bound Si. Conversely, pastures and croplands tend to preserve phytoliths in the soil, which are less reactive, decreasing the potential of DSi export relative to forested ecosystems.

Department/s

  • Quaternary Sciences
  • BECC: Biodiversity and Ecosystem services in a Changing Climate

Publishing year

2014

Language

English

Pages

693-705

Publication/Series

European Journal of Soil Science

Volume

65

Issue

5

Document type

Journal article

Publisher

Wiley-Blackwell

Topic

  • Geology

Status

Published

ISBN/ISSN/Other

  • ISSN: 1365-2389