Limited supply of land

Land makes up only 30 percent of the Earth's surface. Of this, not all are readily available for use.

Areas like swamps, marshes and low-lying coastal areas are constantly waterlogged or flooded with water, while deserts are too dry to be of much use to us. Land can also be damaged through mining or poor farming practices. These types of land are of little use to us if left in their original state.

Even where land is suitable for human use,not all of it is available to us as they may be reserved for certain uses, such as water catchment areas. These are usually areas of forests that collect and channel  rainwater into reservoirs. Land is also set aside for military purposes -- such as training areas and water catchment areas take up more than half of the total land. That leaves a limited area of land for others purposes such as industry and housing. 

Reasons for Land Constraint

 Development of transport systems

As a country develops, more roads and railways have to be built. A good transport network is important for the movement of goods and raw materials, as well as to enable workers to travel between their homes and workplaces. In some cities, over 20 percent of the total land area is set aside for transport facilities such as roads, railways and car parks.

Increasing demand for recreational spaces

With more people, more recreational spaces will have to be provided. Land is needed for a wide range of facilities, ranging from swimming pools to public golf courses and theatres. Some land also has to be set aside as parks and nature reserves for people to enjoy and relax in.

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