Focus
Technology may help save grasslands from fiery wrath
By Huang Zhiling in Sichuan and Jiang Xueqing in Beijing (China Daily)
Updated: 2010-12-09 07:59
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Keeping watch
There are two major causes of grassland fires: natural events, such as lightning or extremely dry and hot weather, and human error, such as a discarded cigarette or electrical fault.
The four methods China adopted to monitor its prairies are observation towers, ground patrols, air patrols and satellite supervision. Each has its own advantages and disadvantages, according to experts.
Satellites are said to cover all grasslands but they can only successfully detect 30 to 50 percent of blazes in a small scale because their resolution power is limited.
Air patrols, on the other hand, offer higher resolution power but cover a much smaller area and is more expensive.
Wildfires are naturally difficult to monitor with satellites as they rely on light during the day and thermal temperatures at night, said a source with the Sichuan meteorological station's agrometeorological center who did not want to be identified.
"When low bushes catch fire, the smoke is not as large as a forest fire, so there's a chance that satellite monitoring efforts may fail, (especially given that) highland temperatures are relatively low and that the perimeter of grassland fires is (often) not significant," the source added.
Hu Yinan contributed to this story.
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A firefighter looks at the devastated grassland in Garze Tibetan autonomous prefecture, Sichuan province, after the wildfire was extinguished on Dec 6. The fire destroyed 33 hectares of land. He Haiyang / for China Daily |
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Firefighters work to extinguish the flames on Dec 5 in Dawu. Local authorities are still looking into the cause of the tragedy, which killed 22 people, including 15 soldiers and five villagers. China News Service |
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 Emergency workers take a rest after a hard day of fighting the wildfire on the Dawu grasslands. The wildfire raged for almost 24 hours, trapping dozens of soldiers and villagers. He Haiyang / for China Daily |
