Geography For Schools

Soils

The best soils for transport infrastructure are stable and flat, but they are also best for agriculture.

Clearance of vegetation for the construction of the transport infrastructure often leads to soil erosion. Local soil pollution by chromium, lead and zinc is caused by heavy transport.

The use of salt and grit in the winter is also a major factor. Oils and other fluids used in cars such as antifreeze and battery acid can be a danger to the environment, as can paints and other bodywork treatments.

Construction works often result in the loss of habitats which is turn results in a loss of species.

Transport links often cause fragmentation. The cutting through of corridors used by animals for obtaining food, finding shelter or for breeding causes a decrease in the number of animals and will eventually result in a loss of species natural territorial spread of animals as offspring seek out new areas. This lack of mobility can lead to poor genetic diversity within colonies.

As evidence of this note the number of animals killed on the road in the late summer and early winter months.

Transport noise, lights and pollution all contribute to increased stress levels in animal populations often leading them to abandon sites due to continued disruption.

Accidental deaths to mature adults can lead to a decrease in the number of animals.

Roads open ways for intruding species, eroded material affects fish spawning sites in rivers and the diversion of waters disturbs water flow which has negative impacts on plankton and may disturb other food chains.

Drainage from large areas can lead to spate conditions in rivers being exaggerated during periods of heavy rain causing problems for juvenile animals and physically carrying pollutants to the river in solid and dissolved form.

Construction of transport infrastructure causes direct pressure on the land. Indirect pressure is caused by urban development that is induced by the transport sector.

Increased land use for transport increases the pressure on biodiversity through habitat loss and fragmentation. It should also be noted however that large transport infrastructure can create wilderness areas supporting a variety of animals and ecosystems due to the reduced use of these areas for leisure, recreation and other industry.

Modifications to the water flow are caused by diversions during the construction which leads to flooding and erosion, often resulting in habitat destruction and silting at areas remote to the site.

Changes in the water tables negatively affect vegetation and often cause loss or contamination of water for drinking and agriculture. Poor drainage systems can lead to unintentional flooding and water retention changing habitats and driving out non-wetland species.

Runoff from roads (hydrocarbons, heavy metals, de-icing chemicals) causes water pollution and the transportation of dangerous goods increases the risk of accidental contamination.

Noise

Continuous noise increases stress levels and leads to the damage of auditory systems and sleeping disorders. Noise may also disturb animal breeding, feeding and migration patterns.