Summary of Land Supply

Land Supply

Land is needed for growing crops, building houses and roads and setting up industries. Due to the increase in the world's population, more and more land is needed for housing, farming and the building of industries. Therefore, there is a shortage of land and there is a limit to the amount of land we can develop for usage. The shortage of land is called land constraint.

Reasons for Land Constraint

1. Population growth

-> With more people, more land is needed for human activities

-> All areas have a carrying capacity, hence with more people, pressure would be added to the land.

2. Increasing demand for housing

-> Growing population leads to an increase in demand for housing.

-> More houses are needed to house the growing population.

3. Growth of industries

-> Growing population leads to an increase in demand for jobs

-> More land is needed to provide more jobs for the growing population.

4. Development of transport systems

-> To enable the movement of goods

-> To enable workers to travel to and from their workplace

(This is to ensure that the country is able to develop)

5. Increasing demand for arable land

(Arable land refers to land which is suitable for growing crops)

-> To produce food for the growing population.

-> Most of the Earth's land surface is unsuitable for growing crops.

6. Increasing demand for recreational spaces

-> With the growing population, more land will need to be set aside for recreational purposes.

-> Land is needed for the development of facilities such as swimming pools, nature reserves, parks and others.

There is a limited supply of land on Earth. About only 30% of the Earth's surface is made up of land. Swamps and low-lying coastal areas are waterlogged and flooded with water, and deserts are too dry for use. Land used for mining or poor farming practices can be damaged. Hence, these land are of little use if it is left in their original state.

Not all of land is available for human use as they may be reserved for other uses, like water catchment areas. Land is also reserved for military purposes, to provide an area for the soldiers to train. In Singapore, about half of the total land is set aside for military purposes and water catchment areas. The rest, is used for other purposes such as housing and recreational spaces.

Responses to the Rising Demand for Land

Due to the limited supply of land, there is competition among people who want to use land. Opportunity cost is known as the cost of not being able to use the same piece of land for the next best use. Thus, land constraint has to be managed properly as it could lead to other problems such as conflicts between people.

1. Increasing the price of land

When the demand for land increases, the available supply of land area cannot meet with the increase in demand. Thus, the price of land may increase. Some people might be able to pay a higher price for a piece of land and this fact would push up the price of land. The way in which prices for goods or services set based on their demand and supply is known as price mechanism.

Hence, due to the high demand for the limited supply of land, the land in cities is usually expensive. Increasing the price of land discourages people from using the land, and thus, this reduces the demand for land.

2. Increasing the supply of land

There are three ways in which man can increase the supply of land available for use. These ways are land clearance, land reclamation, and maximising the use of existing land.

Land clearance

-> clearing of forests (Deforestation)

-> demolishing old buildings

Effectiveness of land clearance

-> land is freed to build new buildings and other facilities.

-> have a negative impact on the environment.

-> habitats of animals and plants are destroyed, resulting in the death of wildlife.

-> leads to negative consequences for the food chain.

Land reclamation

-> the creation of dry land from an area covered by water such as a swamp, lake or sea.

-> also refers to the process of recovering land that is damaged or abandoned and making it usable again.

-> Ways to reclaim land are by landfill, empoldering and reclaiming derelict land.

Prcoess of Landfill (used for the creation of dry land from shallow parts of seas, swamps or marshes)

1. Piles of sand are forced into the seabed to make it more stable.

2. A sand wall is built around the area to keep seawater out. Sand is stored in the sea, just outside the sand wall until it is needed.

3. The sand previously stored in the sea is sucked up and pumped into the enclosed area.

4. A granite wall is built on the side facing the sea after the sand is compressed. This is to prevent the area from being eroded by waves.

5. Trees and vegetation is grown are grown on the reclaimed land to prevent soil erosion and the land is left to rest. The time allowed for the land to rest depends on how the land will be used.

Singapore is an example of a country who uses the landfill method to reclaim land.

Empoldering (the method of reclaiming land from the sea)

-> involves the use of polders (a piece of land in a low-lying area that has been reclaimed from a body of water by building dikes and drainage canals)

-> is a way to control floods

-> although it is usually carried out in low-lying coastal areas, it can be applied to areas that a further inland, such as lakes.

-> commonly carried out in countries in the Netherlands where much of the country lies below sea level and is prone to flooding.

Process of empoldering

1. Around the area to be reclaimed, a dike is constructed to keep water from coming in.

2. Pumps and drainage canals are used to drain the area.

3. Reed (a plant) are sown by aircraft to help the soil farm.

4. The reeds are burnt after three years. The ash is used as fertilisers for the soil.

5. After a period of time (up to 15 years), the polder is ready for growing crops, building houses and constructing roads.

Derelict land

-> Natural disasters like forest fires and floods, as well as human activities, can cause damages to the land.

-> The land cannot be used for certain activities when this happens.

-> Such damaged land is known as derelict land.

-> Improper farming practices lose the fertility of arable land.

(When crops are grown too quickly, there is insufficient time for the nutrients to replace itself. Also, excessive ploughing of land also causes large amounts of soil erosion)

-> Vegetation and soil have to be removed due to mining activities. Huge holes are dug in the ground and these form deep mining pools. Mining waste, which may contain poisonous substances, is left behind after the mining activities and may contaminate the soil.

Process for reclaiming derelict land

(For restoring land which is destroyed due to poor farming practices)

1. Add fertilisers to the soil to restore the nutrients.

(For restoring land which is destroyed due to mining activities)

1. Waste heaps are levelled out and the mining pools are filled.

2. Chemicals are used to treat the contaminated soil.

3. New vegetation can be planted to prevent soil erosion.

Reclaimed mining land can be used for many purposes like agriculture, industry, housing and recreation. For example, Sunway Lagoon Park in Malaysia was an abandoned tin mine which was restored for recreational purposes.

Effectiveness of land reclamation

-> Current technology only allows land to be reclaimed from waters up to fifteen metres in depth.

-> To reclaim land in deeper waters, it will be of high cost.

-> More sand will be needed to fill the area being reclaimed.

-> Not enough sand within the country.

-> Buying sand from other countries increases the overall costs.

-> Land cannot be extended too far out without entering another country's territories.

-> Sea space is needed for shipping activities.

-> Negative impact on the environment (swamps and beaches are destroyed, leading to the death of marine animals and plants)

Maximising use of existing land

-> improvements in technology allow people to live in area previously unsuitable for living.

->Landuse can maximised as land that could not previously be used can now be used to build houses or for other purposes.

Maximising urban landuse

-> In urban areas, the population density is high.

-> Great competition for land.

Mixed landuse

->Landuse planning is the process by which different areas on a piece of land are assigned for for different landuses.

-> To allow the land to meet the needs of more users, countries are developing mixed landuse projects (combination of shopping malls, offices, houses and hotels in one area. These are linked by pedestrian walkways and escalators)

-> Developed on a small scale in cities such as London and Singapore. (e.g. Suntec City)

High Density Building

-> Taller building can be constructed due to technological advances when land is scarce but in high demand.

-> In Singapore, the housing board intends to build flats with 30 storeys or more to maximise the land space.

Advantages of high density building

-> More people can work or be housed on a smaller piece of land.

-> Frees up scarce land for other landuses.

-> Helps to reduce the rate which the country's remaining green spaces are developed.

Disadvantages of high density building

-> Large numbers on people in a small area leads to:

- Crowded environment.

- Traffic congestion

- Higher noise levels

-> These may lead to increased stress levels among the people and reduce their quality of life.

Maximising agricultural landuse

-> countries need more land to grow food to feed their increasing population.

-> There are three ways to do this.

Irrigation

-> Watering crops through artificial means.

-> Allows farmers to grow crops in areas facing water shortage.

-> Water can be channelled through irrigation pipes from water sources such as lakes to a place where water is scarce.

Advantages of Irrigation

-> Ensures a regular supply of water which allows farmers to grow greater amounts and wider varieties of crops.

-> Maximises the use of land.

-> Computerised irrigation systems can water plants automatically and efficiently, reducing the need for human labour.

Disadvantages of Irrigation

-> If not properly maintained, irrigation canals can hold stagnant waters and become breeding sites for mosquitoes, bacteria and other pests.

-> Poor drainage can cause irrigation may cause land to become waterlogged and damages the crops.

-> River water used for irrigation may contain high amounts of dissolved mineral salts which can cause damage to crops.

-> Expensive to construct (especially when dams need to be built across a waterway to create a reservoir)

Terracing

-> Involves the creation of flat strips of land, by cutting a series of steps into hill slopes.

-> Increases the supply of flat arable land

-> More favourable for agriculture cultivation

-> Low walls are built at the end of each step. These walls are known as bunds, which help to slow down the runoff of rainwater so that it can seep into the soil and b absorbed by the plant roots. The walls also hold water in an enclosed area to create the flooded conditions needed for growing crops such as padi.

Advantages of terracing

-> Inexpensive method of increasing the area of arable land.

-> Bunds used in terracing prevent the soilf from being washed away.

-> The flant land created by terracing make it possible for modern machinery to be used and hence, makes farming more efficient.

Disadvantages of terracing

-> Terraces are difficult to construct

-> A lot of human energy and time is needed to cut the steps into hill slopes.

-> A lot of effort is needed to maintain the terraces after construction.

-> When bunds are damaged, they may not be able to hold the soil back and this will result in soil erosion.

Soil-less farming

-> Enables crops to be grown closer together

-> Maximises the landuse for argicultural purposes.

-> Examples are hydroponics and aeroponics farming.

Advantages of soil-free farming

-> Plants can be grown closer together

-> More crops can be grown on a single area of land at the same time

-> Effective in increasing the output of crops

-> Sufficient amounts of nutrients can be delivered and distributed to plants evenly at regular intervals, resulting in better quality of crops.

-> Prevent the growth of weeds and the invasion of insects

Disadvantages of soil-free farming

-> Farmers must invest in high technology equipment and specially prepared nutrient solutions for the plants. This can be very costly.

-> Impractical if farmers do not receive enough training to know how to operate the high technology equipment.

Conserving land

-> Refers to the careful use of land resources to ensure their damage is kept to a minimum.

-> One way is to set aside land as nature reserves, where land is managed to protect wildlife and natural features for research or study.

-> In Singapore, 5% of the total land area is set aside as nature reserves. (E.g. Sungei Buloh, where it's protected for its natural heritage)

~Kimberley Lim~