Agriculture Reference
In-Depth Information
TABLE 1:
Cont.
Species
Ecological
category
Ecological niche
Characteristic
features
Beneficial trait
Octolasion
cyaneum,
Polyhumic
endogeic
Top soil (A1)
Small size, un-
pigmented, forms
horizontal burrows,
rich soil feeder
O. lacteum,
Pontoscolex
corethrurus,
Mesohumic
endogeic
A and B horizon
Medium size,
unpigmented, forms
extensive horizontal
burrows, bulk (A1)
soil feeder
Allolobophora
chlorotica,
Aminthas sp.
Oligohumic
endogeic
B and C horizon
Very large in size,
unpigmented, forms
extensive horizontal
burrows, feeds on
poor, deep soils
L. terrestris,
Anecics
Permanent deep
burrows in soil
Large in size,
dorsally pigmented,
forms extensive,
deep, vertical perma-
nent burrows, low
reproductive rate,
sensitive to distur-
bance, phytogeopha-
gous, nocturnal
Forms vertical
burrows affect-
ing air-water
relationship and
movement from
deep layers to
surface helps in
efficient mixing
of nutrients
L. polyphemus,
A. longa
9.4 DIVERSITY OF BACTERIA ASSOCIATED WITH EARTHWORMS
Earthworm's ability to increase plant nutrient availability is likely to be
dependent on the activity of earthworm gut microflora. Earthworms indi-
rectly influence the dynamics of soil chemical processes, by comminuting
the litter and affecting the activity of the soil micro-flora (Petersen and
Luxton 1982; Lee 1985; Edwards and Bohlen 1996). Interactions between
earthworms and microorganisms seem to be complex. Earthworms ingest
