Long-term removal of wheat straw decreases soil amorphous silica at Broadbalk, Rothamsted

A - Papers appearing in refereed journals

Guntzer, F., Keller, C., Poulton, P. R., McGrath, S. P. and Meunier, J-D. 2012. Long-term removal of wheat straw decreases soil amorphous silica at Broadbalk, Rothamsted. Plant and Soil. 352 (1-2), pp. 173-184.

AuthorsGuntzer, F., Keller, C., Poulton, P. R., McGrath, S. P. and Meunier, J-D.
Abstract

Aims
Most cereals accumulate Si in their shoots. Soil bioavailability of Si may be a constraint on the beneficial role of silica in cereals but it is not yet well supported by field data. The aim of this study is to evaluate the long-term impact of wheat straw exports on the pool of soil phytoliths, which, it is suggested, represents the most labile and renewable pool of soil Si.

Methods
We measured the amorphous Si (ASi) in soils from several experiments at Rothamsted Research (UK), which provided long-term soil data back to the middle of the 19th century, using two alternative extraction techniques: Na2CO3 (referred to as ASnc) or zinc bromide extraction (referred to as ASizb).

Results
All samples showed a similar range of ASnc and ASizb but low values (0.1–3.4 mg g−1 DW) compared to published data on natural ecosystems. In the Broadbalk experiment, a decrease over time in ASi in the topsoil samples is in good agreement with the hypothesis that cropping and exports of straw leads to depletion of soil phytoliths. A decrease in Si concentration in straw samples was observed between 1883 and 1944. From 1944 to the present, Si concentration increased irregularly in the straw, probably as the result of liming, which enhanced the dissolution of the remaining phytoliths through increasing pH. In the reforested Geescroft field the higher phytolith concentration in the modern topsoil samples is in good agreement with a re-building of phytolith storage from litter input in an acidic environment.

Conclusions
Our results therefore support the hypothesis that export of wheat straw leads to a decrease in bioavailable Si.

Keywordsphytolith; silicon; bioavailability; cereals; sustainability
Year of Publication2012
JournalPlant and Soil
Journal citation352 (1-2), pp. 173-184
Digital Object Identifier (DOI)doi:10.1007/s11104-011-0987-4
Open accessPublished as non-open access
FunderBiotechnology and Biological Sciences Research Council
Lawes Agricultural Trust
Funder project or codeSEF
The 'Classical' experiments: Broadbalk and Park Grass [2001-2012]
Maintaining soil resilience and function for sustainable land management
Publisher's version
Copyright license
Publisher copyright
File Access Level
Open
Output statusPublished
Publication dates
Online20 Sep 2011
Publication process dates
Accepted30 Aug 2011
PublisherSpringer
Copyright licensePublisher copyright
ISSN0032-079X

Permalink - https://repository.rothamsted.ac.uk/item/8qq36/long-term-removal-of-wheat-straw-decreases-soil-amorphous-silica-at-broadbalk-rothamsted

Restricted files

Publisher's version

Under embargo indefinitely

8 total views
0 total downloads
1 views this month
0 downloads this month