Agriculture Reference
In-Depth Information
Wildlife in the countryside is under pressure as
never before from many causes such as changing
agricultural practices, use of pesticides, urban spread
and introduced species. The value of gardens for
wildlife has begun to be appreciated in recent years
and they are seen more and more as an important
contribution to conservation of our natural heritage.
An understanding of the ways in which wildlife can be
can be encouraged and supported, while retaining all
the desirable qualities of a garden, is useful to know.
To know what makes a good garden for wildlife it is
useful to understand some ecological principles.
'biodiversity, conservation, ecosystem services,
and the well-being of the human population'.
See companion website for more information on
the BUGS project.
An understanding of the basics of
ecology
can
help us design and manage gardens in a way that
supports all the organisms that live there. In effect, it
is the recipe for a healthy, wildlife-friendly garden.
Broadly speaking, ecology takes over where the
study of individual organisms ends. It investigates
the relationships between the organisms themselves
and the environment they live in. Ecologists therefore
study groups of plants and animals (
populations
)
living together in a
community
which, together with
their non-living environment, form
ecosystems
. On a
global scale, major regional communities of organisms
form well-recognized
biomes
.
Studies on garden wildlife
Between 1972 and 1991, Jennifer Owens
recorded wildlife in her garden in Leicester.
She provided a range of heights and growth
forms in her planting, grew flowers for insects
and plants with fruits for birds. Apart from
a few concessions (minimal pruning and
clearing, dead heading to prolong flowering
and never using pesticides), she managed her
garden conventionally and described it as 'a
typical suburban garden . . . neat, attractive
and productive' with a lawn, some herbaceous
borders, a rockery and fruit and vegetables. A
huge diversity of organisms was found, some
422 species of plants, 1,602 insects, 121 other
invertebrates and 59 vertebrates representing
a large proportion of the fauna of Britain and
Ireland. Some species were common, many
were rare and some were new to science. She
commented that 'gardens would seem to be of
considerable significance in conservation'.
Since then, studies carried out by the University
of Sheffield across the UK (Biodiversity in Urban
Gardens in Sheffield or BUGS project) have
evaluated urban gardens for wildlife in several
UK cities. They too found an astonishing range
of plants and animals - for example, 42% of the
UK's plants were found in a combined garden
area of two football pitches. They concluded
surprisingly that small gardens were just as
good as large gardens, city centre gardens were
as good as suburban gardens and all gardens
were good for wildlife whether specifically
managed for this or not. Trees were found to be
the most important factor and piles of logs were
beneficial, while artificial methods of attracting
wildlife such as bird boxes and insect hotels
varied in their success. They concluded that any
reduction in urban gardens would impact on
The term '
ecology
' is formed from the Greek
words
oikos
, meaning a house or place, and
logos
meaning knowledge or understanding.
Ecology and gardens
Communities
A
community
is a group of populations in a
given area or
habitat
.
A
population
is defined
as a group of individuals of one species which
interbreed - for example, all the weed species
Senecio vulgaris
in a garden, or all the individual
hedgehogs within a certain area.
A community is a group of plant and animal species
(populations) living within a particular area (
habitat
).
'Wild' communities are defined by either the habitat
in which they occur
(e.g.
a 'lake community')
or
by a particular plant species which is dominant (e.g. a
'grassland community'). A
microhabitat
is on a much
smaller scale (e.g. under a log or against a wall) and its
community may differ considerably from that of the
larger habitat it occupies. Gardens are themselves a
type of habitat and often have many microhabitats
which increase the variety (biodiversity) of organisms
that live there.
Populations may be restricted to a very specific
habitat - for example,
Epilobium palustre
(marsh
willow herb) is only found in slightly acidic ponds.
However, some populations can occupy a wide range
of habitats such as
Rubus fruticosus
(blackberry)
