The
studies of below-ground
biodiversity were
concentrated on four
key functional groups
of soil biota:
(1) microsymbionts
such as N-fixing bacteria
and mycorrhizal fungi,
(2) macrofauna such
as earthworms and
termites which regulate
soil porosity and
organic matter dynamics,
(3) nematodes which
include many plant
pests as well as regulators
of soil nutrient fluxes,
and (4) groups of
soil micro-organisms
which are important
drivers of nutrient
cycles.
The
ASB data show
that there are
substantial differences
among land uses
with respect to
the diversity
and/or abundance
of one of more
of the groups
of soil biota.
For example, there
is a drastic decrease
in the number
of termite species
(Figure
4; Swift et al.,
1998) and
the elimination
of soil-feeding
termites as
land-use intensity
increases and
trees are removed
from the system
in Indonesia.
Similar findings
have been documented
for earthworms
in Brazil. Such
changes in below-ground
biodiversity may
have significant
implications for
system productivity.
The availability
of these data
on the soil biota,
together with
those on nutrient
and carbon stocks,
provides information
that facilitates
the development
of management
strategies for
improved soil
productivity.
BACK
Page
preparation by Dr.
Erick C.M. Fernandes,
Cornell University.
--ASB Global Coordinator
(1998-1999)--
