[permaculture] Biotope vs. "ecological niche"

Lawrence F. London, Jr. venaurafarm at bellsouth.net
Sat Oct 24 23:40:49 EDT 2009


More related and interesting concepts:

Niche differentiation
 From Wikipedia, the free encyclopedia

The term niche differentiation (synonymous with niche segregation, niche 
separation and niche partitioning), as it applies to the field of 
ecology, refers to the process by which natural selection drives 
competing species into different patterns of resource use or different 
niches. This process allows two species to partition certain resources 
so that one species does not out-compete the other as dictated by the 
competitive exclusion principle; thus, coexistence is obtained through 
the differentiation of their realized ecological niches.

Niche differentiation is a process which occurs through several 
different modes and on multiple temporal and spatial scales. In most 
cases, niche differentiation has created a relationship between two 
species where current competition is small or non-existent. Because of 
this, the presence of niche differentiation can be methodologically 
difficult to prove or disprove. The lack of evidence for current or past 
competition can blur the line between 1) two competitive species 
differentiating their niches to allow coexistence as opposed to 2) two 
non-competing species which occupy similar niches. It is important to 
keep in mind that niche differentiation and inter-specific competition 
cannot always be considered linked.

As an example of resource partitioning, seven Anolis lizards in tropical 
rainforest share common food needs — mainly insects. They avoid 
competition by occupying different sections of the rainforest. Some live 
on the leaf litter floor while others live on shady branches, thereby 
avoiding competition over food in those sections of the forest. All 
resources are subject to partitioning, for example; space, food, nesting 
sites. This minimizes competition between similar species.

Habitat
 From Wikipedia, the free encyclopedia
   (Redirected from Habitat (ecology))

A habitat (which is Latin for "it inhabits") is an ecological or 
environmental area that is inhabited by a particular animal and plant 
species.[1][2] It is the natural environment in which an organism lives, 
or the physical environment that surrounds (influences and is utilized 
by) a species population.[citation needed]

The term "species population" is preferred to "organism" because, while 
it is possible to describe the habitat of a single black bear, we may 
not find any particular or individual bear but the grouping of bears 
that comprise a breeding population and occupy a certain biogeographical 
area. Further, this habitat could be somewhat different from the habitat 
of another group or population of black bears living elsewhere. Thus it 
is neither the species nor the individual for which the term habitat is 
typically used.

A microhabitat is a physical location that is home to very small 
creatures, such as woodlice. Microenvironment is the immediate 
surroundings and other physical factors of an individual plant or animal 
within its habitat.


Microclimate
 From Wikipedia, the free encyclopedia

A microclimate is a local atmospheric zone where the climate differs 
from the surrounding area. The term may refer to areas as small as a few 
square feet (for example a garden bed) or as large as many square miles 
(for example a valley). Microclimates exist, for example, near bodies of 
water which may cool the local atmosphere, or in heavily urban areas 
where brick, concrete, and asphalt absorb the sun's energy, heat up, and 
reradiate that heat to the ambient air: the resulting urban heat island 
is a kind of microclimate.

Another contributory factor to microclimate is the slope or aspect of an 
area. South-facing slopes in the Northern Hemisphere and north-facing 
slopes in the Southern Hemisphere are exposed to more direct sunlight 
than opposite slopes and are therefore warmer for longer.

The area in a developed industrial park may vary greatly from a wooded 
park nearby, as natural flora in parks absorb light and heat in leaves, 
that a building roof or parking lot just radiates back into the air. 
Advocates of solar energy argue that widespread use of solar collection 
can mitigate overheating of urban environments by absorbing sunlight and 
putting it to work instead of heating the local surface 
objects.[citation needed]

A microclimate can offer an opportunity as a small growing region for 
crops that cannot thrive in the broader area; this concept is often used 
in permaculture practiced in northern temperate climates. Microclimates 
can be used to the advantage of gardeners who carefully choose and 
position their plants. Cities often raise the average temperature by 
zoning, and a sheltered position can reduce the severity of winter. Roof 
gardening, however, exposes plants to more extreme temperatures in both 
summer and winter

Microclimates can also refer to purpose made environments, such as those 
in a room or other enclosure. Microclimates are commonly created and 
carefully maintained in museum display and storage environments. This 
can be done using passive methods, such as silica gel, or with active 
microclimate control devices.

Soil Types

The type of soil found in an area can also affect microclimates. For 
example, soils heavy in clay can act like pavement, moderating the near 
ground temperature. On the other hand; if soil has many air pockets, 
then the heat could be trapped underneath the topsoil, resulting in the 
increased possibility of frost at ground level [4]



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