Agriculture Reference
In-Depth Information
Table 3.14.2.
Abundance of morphological classes of particles observed with TEM in fraction
< 2
µ
m.
% total surface of particles
Organomineral
aggregates
Organic
particles
Mineral
particles
No. of
particles
analysed
Mean
Mean
Mean
SD
SD
SD
Forest
219
47.9
13.4
12.0
3.6
40.0
12.4
Cultivated 7 years
422
9.4
8.4
4.5
4.3
89.5
9.7
Cultivated 35 years
570
5.9
7.3
6.4
10.0
87.7
16.9
Electron micrographs of the < 2
m fractions.
µ
with clay minerals and that disruption of the microaggregates by tillage or
exposure to rain in cultivated soil caused its de-protection.
Acknowledgements
The authors thank D. Arrouays for site selection and sampling, J.
Lapeyronnie for the thin sections, and M. Perrier for laboratory assistance.
References
Arrouays, D. (1992) Veracrisols. In: Baize, D. and Girard, M.C. (eds)
Référentiel
Pédologique
. INRA Editions, Paris, pp. 171-174.
Balesdent, J., Besnard, E., Arrouays, D. and Chenu, C. (1998) The dynamics of
carbon in particle-size fractions of soil in a forest-cultivation sequence.
Plant
and Soil
201, 49-57.
Cambardella, C.A. and Elliott, E.T. (1992) Particulate organic matter across a
grassland cultivation sequence.
Soil Science Society of America Journal
56,
777-783.
Chenu, C. and Jaunet, A.M. (1992) Cryoscanning electron microscopy of microbial
extracellular polysacharides and their association with minerals.
Scanning
14,
360-364.
Chenu, C., Puget, P. and Balesdent, J. (1998) Clay-organic matter associations in
soils: microstructure and contribution to soil physical stability. In:
Proceedings of
the 16th World Congress of Soil Science
, CDROM, Cirad, Montpellier, France.
Chenu, C., Le Bissonnais, Y. and Arrouays, D. (2000) Organic matter influence on
clay wettability and soil aggregate stability.
Soil Science Society of America
Journal
64 (in press).
Christensen, B.T. (1992) Physical fractionation of soil and organic matter in
primary particle size and density separates.
Advances in Soil Sciences
20, 1-90.
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