Agriculture Reference
In-Depth Information
TABLE 6.1
Earthworm Tissue Production in Relation to Food (mg fresh mass g
dry mass)
Ï
1
Lumbricus
terrestris
Aporrectodea
caliginosa
Mixed
spp.
Grass,
Lolium perenne
1.5% nitrogen (Boyle 1990)
82Ï251
17Ï69
118Ï320
Grass,
Festuca pratensis
Roots 0.8% nitrogen (Bostrm and Lofs-Holmin 1986)
53 (17)
Shoots 1.7Ï2.2% nitrogen (Bostrm and Lofs-Holmin 1986;
Bostrm 1987)
182 (152) to 247
Decayed 2.2-2.4%N (Bostrm 1987)
187Ï225
Willow,
Salix burjatica
1.8% nitrogen (Curry and Bolger 1984)
180Ï250
Barley,
0.7Ï2.9% nitrogen (Bostrm and
Lofs-Holmin 1986; Bostrm 1987)
Hordeum distichum
74 (39) to 224 (206)
Barley, decayed 1.1Ï1.2% nitrogen (Bostrm 1987)
242Ï255
Barley residues in field (N.C. Andersen 1983)
120Ï180
Lucerne,
2.4Ï4.0% nitrogen (Bostrm and
Lofs-Holmin 1986; Bostrm 1987)
Medicago sativa
106 (76) to 132
Lucerne decayed 2.2Ï2.9% nitrogen (Bostrm 1987)
175Ï249
Note
: Values in parentheses are corrected to allow for growth in unamended soil.
TABLE 6.2
Earthworm Growth Rates in Peat/Mineral Soil Cultures under
Different Feeding Regimes (mg ind
-1
d
-1
± SE)
Lumbricus
terrestris
Aporrectodea
caliginosa
n
n
Milled grass
On the surface
18.9 ° 1.2 a
7
5.2 ° 1.6 a
6
Mixed in
6.2 ° 1.4 b
6
2.7 ° 0.7 b
7
Chopped grass
On the surface
17.7 ° 2.3 a
7
2.1 ° 0.6 b
8
Mixed in
8.0 ° 2.2 b
6
1.2 ° 0.2 b
5
n
= number of surviving earthworms.
Note:
Means in the same column followed by the same letter (a or b) do not differ
significantly at
p
< 0.05 in ANOVA and
t
-tests.
Source:
Boyle 1990.
where it could be located easily and concentrated, but rather more surprisingly, this was also the
case for
A. caliginosa
. It may be that
A. caliginosa
benefited by gaining access to concentrations
of decaying grass residues in
L. terrestris
burrows. However,
A. caliginosa
growth rates were low
compared with those recorded when
was reared individually under comparable
conditions (Bostrm and Lofs-Holmin 1986), suggesting that
A. caliginosa
A. caliginosa
was at a net disadvantage
as a result of its association with
.
In addition to its nutrient content, litter quality is influenced by factors such as carbohydrate
content and the concentration of phenolic compounds (especially tannins), which can reduce
L. terrestris
