Our Environment - Mining and the Environment: From Ore to Metal - page 308

TABLE 7.3
Biodiversity Checklist of the Three Components of Biodiversity - Composition, Structure, and Function

Components of Biological Diversity

Level of biological
diversity

Composition Structure (temporal) Structure (spatial:

horizontal and vertical)

Key processes

Genetic diversity Minimal viable popula-

tion (avoid destruction by
inbreeding/gene erosion)

Cycles with high and low
genetic diversity within a
population

Dispersal of natural genetic
variability

Exchange of genetic material
between populations (gene
fl o w )

Local cultivars Dispersal of agricultural

cultivars

Mutagenic infl uences

Living modifi ed organisms Intraspecifi c competition

Species diversity Species composition, genera,

families etc., rarity/abundance,
endemism/exotics

Seasonal, lunar, tidal, diurnal
rhythms (migration, breeding,
fl owering, leaf development,
etc.)

Minimal areas of species to
survive

Regulation mechanisms
such as predation, herbivory,
parasitism

Population size and trends Reproductive rate, fertility,

mortality, growth rate.

Essential areas (stepping
stones) for migrating species.

Interactions between species

Know key species (essential
role)

Reproduction strategy Niche requirements within

ecosystem (substrate prefer-
ence, layer within ecosystem)

Ecological function of a
species

Conservation status Relative or absolute isolation

Ecosystem diversity Types and surface area of

ecosystems

Adaptations to/dependency
on regular seasonal rhythms

Spatial relations between
landscape elements (local
and remote)

Structuring process(es) of key
importance for the mainte-
nance of the ecosystem itself
or for other ecosystems

Uniqueness/abundance Adaptations to/dependency of

on irregular events; droughts,
fl oods, frost, fi re, wind

Spatial distribution (continu
-ous or discontinuous/patchy)

Succession stage, existing
disturbances and trends
( autonomous
development)

Succession (rate) Minimal area for ecosystem

to survive

Vertical structure (layered
horizons, stratifi ed)

Source:
Convention on Biological Diversity, COP 6 Decision VI/7 ( www.unep.org )

Why is Biodiversity Important?

Biodiversity values, conveniently categorized as economic, social, and intrinsic values,
are often underestimated. Economic values comprise biodiversity as a source of harvest-
able goods (food, medicines, building materials, and products sold for income or used as
inputs to other economic activities) and its regulative function of natural processes and the