Fires In Nature Flashcards
Are wildfires common
Wildfires, commonly known as bushfires (Australia) or brush fires (USA/Canada), are a normal occurrence in many ecosystems.
What are managed fires
Managed fires are frequently used in conservation areas such as wilderness (for example New South Wales) and remote national parks (for example Yellowstone) as a necessary and beneficial tool of ecosystem management.
What are wildfires
Wildfires are human induced fires that have got out of control and can no longer be classed as managed, or have been deliberately started with malicious intent or through carelessness. Many wildfires occur naturally as a result of lightning strikes, although it is estimated that lightning causes only 10% of wildfires.
What does the nature, intensity and rate of spread of a wildfire depend on
The types of plants involved, the topography, the strength and direction of the winds, and the relative humidity of the air in the region.
Wildfires are particularly associated with areas experimenting semi-arid climates where there is enough rainfall for vegetation to grow and provide a ‘fuel’, yet with a dry season to promote conditions for ignition.
How do fires travel
Some fires travel close to the ground, others spread via the canopies of fall trees.
Where are wildfires concentrated
Concentrated in parts of Australia (New South Wales and Victoria), Canada (British Columbia), the USA (California and Florida), South Africa and Southern Europe (Mediterranean areas). Some geographers have suggested that such fires have become more prevalent in these areas as there is more movement of people into the countryside, as well as an increased incidence of drought due to climate change.
Traditionally, why have wildfires not been associated with areas of tropical rainforest
Because of the high humidity and all year round rainfall.
However, the burning of the rainforest in Indonesia, for example for clearance and forest mismanagement by logging companies, combined with the drying effect of El Niño events, have revised this view.
The combination of drying winds and the burning of relatively moist timber has led to
The combination of drying winds and the burning of relatively moist timber has led to particularly smoky wildfire related events in parts of Southeast Asia in recent years.
Toxic hazes from such fires, combined with other forms of air pollution, have been an increasingly common phenomenon in cities such as Kuala Lumpur and Singapore.
Tell me the impacts of wildfires
Loss of timber, livestock and crops
Loss of valuable plant species and the creation of areas dominated by fire resistant scrub
Damage to soil structure and nutrient content, which occurs over a wide area
Loss of wildlife, of particular concern when rare or endemic species are involved
In the case of extensive fires, loss of vegetation leading to an increased risk of flooding
Temporary evacuation usually requiring emergency aid for the areas affected
Property loss increasing as a result of settlement expansion into at risk areas
Release of toxic gases and the particulate pollution
Risk to firefighters (although loss of life in general is quite low)
Heavy impact on emergency services (huge costs and large numbers of people Involved in controlling the outbreak)
What does pryophytic mean
Plants resistant to fire
What we the 2 categories that responses and risk management strategies fall into
Prevention and protection
What are the responses and risk management strategies for prevention of wildfires
In many countries such as Australia, Greece and Spain, the main approach to fire management has been to extinguish all fires as they occur, especially in populated areas or near to high value timber reserves (mitigation).
Management to modify wildfires also concentrates on reducing or eliminating the fuel supplies from the potential path of the fire by controlled burning. This practice is not only controversial, but also risky.
Technology to warn areas at risk. Aircraft and satellites are used to carry out infrared sensing to check surface ground temperatures and signs of eco stress from desiccation.
Tell me about the responses and risk management strategies for protection against wildfires
Community preparedness leading to early warning through the use of fire towers. Citizens can be trained to act as auxiliary firefighters, to organise evacuation and coordinate emergency firefighting.
Education concerning home safety in high risk areas. Supplies of fuel should be reduced, wood stores stacked correctly, and adequate water hose and ladders should be made available. Householders are also advised to remove dead leaves from gutters. School education concentrates on ensuring young people understand the dangers of arson and casual cigarette use, and the need to adhere to barbecue laws in at risk areas.
Land use planning (adaptation). Risk management identifies areas of high vulnerability, and planning legislation ensures houses are built in low density clusters with at least 30m set back from any forested area. New developments can be designed with fire breaks and wide roads to allow access for firefighting equipment
Fire resistant housing design is increasingly important in at risk areas
Insurance is another option, although expensive and difficult to obtain in fire - prone areas.
