Wednesday, January 25, 2012

Spatial patterns

(http://una.edu/geography/lights_night/step_1.htm)

What are spatial patterns? 
A spatial pattern is a perceptual structure, placement or arrangement of objects on Earth. It also includes the space in between those objects. Patterns maybe recognised because of their arrangement; maybe in a line or by a clustering of points.

Some questions that you may ask:
1) Is there an area that is more/less dense than others?
2) How do we calculate population density?
3) Are there clusters of objects?
4) Is there a randomness or a uniformity in the locations of various objects?

Spatial patterns usually refer to the patterns by which buildings have been arranged.

1) Is there an are that is more/less danse than others?
The answer is yes, there are areas that are mor dense than others. This may be due to the main function of a settlement, the way of life and the amenities that the settlement has.

More dense:


Less dense:


There are also areas of varying densities withim a country. For instance, China:


2) how do we calculate population density?
Simply divide the total number of people over the total land area.

3) are there clusters of objects?
We can classify settlements accordind to how the buildings are arranged. A settlement pattern shows how buildings are arranged in a settlement. There are three types of settlement patterns- dispersed, linear and nucleated.

Dispersed settlement patterns are made up of individual buildings scattered over a wide area. These buildings mat be separated by large open spaces, farmlands, forests or grasslands. Dispersed settlements are also found in hilly areas where it is difficult to build houses and cultivate crops. Thus, people tend to spread out to settle in the best places available. In addition, in places where natural resources or fertile soil is limited, large plots of land are needed to support each household. This ensures that there is enough land  for people to cultivate crops or to obtain resources from the ground. As a result, houses are dispersed.
Example:

 Linear settlements are located along main transport routes such as roads, railways, rivers and canals. Not only do these trasport routes make travelling easy, they may also serve as a source of livelihood for the people living nearby. For example, a fisherman may live alongside a river as rivers are a source of fish. As transport routes are usually arranged in a linear pattern, the settlements built alongside them naturally take on the same pattern.
Example:



Nucleated settlements are made up of buildings clustered together in an area. They are usually the meting point of transport routes, such as rivers, roads and railway lines.The buildings are clustered togetherso that the resources such as water and electricity can be shared. Sometimes, houses are clustered together as there is a shortage of flat land for the buildings to spread out. An example is a settlement locted within a valley that is surrounded by steep slopes.
Example:


4) is there a randomness or uniformity in the locations of various objects?
Refer to point number 3 :)

Saturday, January 14, 2012

Birth rate

What makes birth rate high?

-lack of knowledge about contraceptives
-low education
-certain religions believe in the importance of large families
-family oriented people, less career minded
-desire for a male offspring (some families want a male offspring to carry on the family name, thus couples that have daughters tend to keep trying to have a son)
-early marriages
-high infant mortality rates
-large families gives status (in some developing countries)

What makes birth rates low?

-use of contraceptives
-career oriented people
-late marriages
-spending too much time on education
-low infant mortality rates

Population growth impacts

How does a changing population affect the world?
(increase)

-growth of urban areas
-increased price of land
-mixed landuse
-increasing demand for housing
-growth of industries
-development of transport systems
-increasing demand for recreational spaces
-growth of agriculture
-limited supply of fresh water
-change in lifestyle

http://www.wisegeek.com/what-are-the-effects-of-population-growth.htm
The effects of population growth are varied and vast. While population growth, of any species, may be beneficial to a certain extent, there may come a time when the number in the population exceeds the natural resources available to sustain it. This is referred to as overpopulation. The consequences of such an event are severe and major.

The population growth of any animal, if left uncontrolled can become burdensome. Farmers have noted, for many centuries, what the effects of an uncontrolled predator population can do to livestock. Once their natural prey run out, or are harder to find, the predators may turn to domesticated animals, despite the risks. This can cause a severe hardship on any family depending on those animals for survival.

However, when most think of a growing population, they do not think of other animals. The prime fear in most people's minds is the population growth of their own species. As humans leave a much larger footprint on the environment than any other creature, uncontrolled overgrowth can be especially devastating.

First, as the population grows the opportunities for quality, available housing may become an issue. More people crowded into less space is not a good combination in any locality. As space is taken up, it becomes more valuable. Eventually, it begins to affect to poorest in the area. In the long run the effect of population growth may be substandard housing or homelessness.