In comparison to herbaceous plant materials, a larger proportion of arabinose in
the composition of non-forest soils was notable. This was ascribed to more recalcitrant nature of L-arabinose than D-xylose in the microbial decomposition of plant
materials in soil.
The monosaccharide composition of ECM fungal sclerotium grain (SG) collected
from sub-alpine forest soil was dominated by EH-glucose, 80%, followed by small
proportion of mannose, galactose, and NEH-glucose. Saccharides of SG occupied
3.6% of the total of forest soil from which SG was collected. Sclerotia-forming ECM
fungal species such as Cenococcum geophilum might be key sources of forest soil
polysaccharides.
Keywords Accumulation · Cenococcum geophilum · Decomposition · Forest soil ·
Monosaccharide composition · Plant polysaccharides · Sclerotium grain · Soil
polysaccharides
6.1 Introduction
Polysaccharides in soil significantly affect the physical, chemical, and biological
properties of soil, thereby affecting plant growth, management of arable soil, and soil
resource conservation. Several differences in playing role in soil process between
plant polysaccharides and microbial polysaccharides have been discussed (Cheshire
1979; Oades 1984). For instance, microbial polysaccharides contribute more to
stabilizing soil micro-aggregates than plant polysaccharides (Cheshire et al. 1983,
1984; Puget et al. 1999).
Saccharides in soil originate from organisms mostly in form of polysaccharides.
Surface soil receives plant materials which contain polysaccharides cellulose, hemicelluloses, and pectin as major constituents of cell wall. Soil microbes decompose
the plant materials, and the organisms are themselves made up predominantly of
polysaccharides. Fungal cell wall is composed of a polysaccharide-based threedimensional network and the saccharides account for more than 90% of cell wall
(Latgé 2007; Gow et al. 2017). Bacteria produce variety of glycoconjugates and
polysaccharides of enormous structural diversity and complexity (Whitfield et al.
2017).
Saccharides can be acidic, neutral, and basic, and neutral saccharides are the
predominant in soil. The neutral saccharide content varies widely from less than 0.5
to more than 25 g kg
À1 soil (Fig. 6.1). Neutral saccharides account for 4–14% of soil
organic matter (SOM) by carbon; the higher the SOM content, the smaller the
proportion of neutral saccharides tend to be (Fig. 6.1). Acidic saccharides,
glucuronic acid and galacturonic acid of arable and grassland soil account for
small portion, 0.23–1.5% of SOM by carbon (Benzing-Purdie and Nikiforuk 1988;
Amelung et al. 1999a). Basic saccharides, glucosamine and galactosamine of arable
and grassland soil account for 1.0–4.6% of SOM by carbon (Benzing-Purdie 1984;
Amelung et al. 1999b). Mannosamine in grassland soil occupied only 1.6–2.6% of
total amino sugars (Amelung et al. 1999b).
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S. Murayama and Y. Sugiura
the composition of non-forest soils was notable. This was ascribed to more recalcitrant nature of L-arabinose than D-xylose in the microbial decomposition of plant
materials in soil.
The monosaccharide composition of ECM fungal sclerotium grain (SG) collected
from sub-alpine forest soil was dominated by EH-glucose, 80%, followed by small
proportion of mannose, galactose, and NEH-glucose. Saccharides of SG occupied
3.6% of the total of forest soil from which SG was collected. Sclerotia-forming ECM
fungal species such as Cenococcum geophilum might be key sources of forest soil
polysaccharides.
Keywords Accumulation · Cenococcum geophilum · Decomposition · Forest soil ·
Monosaccharide composition · Plant polysaccharides · Sclerotium grain · Soil
polysaccharides
6.1 Introduction
Polysaccharides in soil significantly affect the physical, chemical, and biological
properties of soil, thereby affecting plant growth, management of arable soil, and soil
resource conservation. Several differences in playing role in soil process between
plant polysaccharides and microbial polysaccharides have been discussed (Cheshire
1979; Oades 1984). For instance, microbial polysaccharides contribute more to
stabilizing soil micro-aggregates than plant polysaccharides (Cheshire et al. 1983,
1984; Puget et al. 1999).
Saccharides in soil originate from organisms mostly in form of polysaccharides.
Surface soil receives plant materials which contain polysaccharides cellulose, hemicelluloses, and pectin as major constituents of cell wall. Soil microbes decompose
the plant materials, and the organisms are themselves made up predominantly of
polysaccharides. Fungal cell wall is composed of a polysaccharide-based threedimensional network and the saccharides account for more than 90% of cell wall
(Latgé 2007; Gow et al. 2017). Bacteria produce variety of glycoconjugates and
polysaccharides of enormous structural diversity and complexity (Whitfield et al.
2017).
Saccharides can be acidic, neutral, and basic, and neutral saccharides are the
predominant in soil. The neutral saccharide content varies widely from less than 0.5
to more than 25 g kg
À1 soil (Fig. 6.1). Neutral saccharides account for 4–14% of soil
organic matter (SOM) by carbon; the higher the SOM content, the smaller the
proportion of neutral saccharides tend to be (Fig. 6.1). Acidic saccharides,
glucuronic acid and galacturonic acid of arable and grassland soil account for
small portion, 0.23–1.5% of SOM by carbon (Benzing-Purdie and Nikiforuk 1988;
Amelung et al. 1999a). Basic saccharides, glucosamine and galactosamine of arable
and grassland soil account for 1.0–4.6% of SOM by carbon (Benzing-Purdie 1984;
Amelung et al. 1999b). Mannosamine in grassland soil occupied only 1.6–2.6% of
total amino sugars (Amelung et al. 1999b).
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S. Murayama and Y. Sugiura