In 1999 there was a fire in San Bernardino County which burned various vegetation types. This lab’s goal is to determine the total burn area, which types of vegetation were affected and to what degree. To answer these questions it required that I upload data which showed representative polygons of the burn areas over a six day time span. These various polygons sometimes overlapped at certain points, indicating that these areas continued to burn between the time periods in which the data was taken. To remove these overlaps, I combined these six polygons into one overall burn area boundary feature. Next, I merged the data containing California’s vegetation types to fall within the boundary of the burn area. I used ArcToolbox to intersect these two layers—California’s vegetation types and the burn area boundary—and thus created a new layer which showed the different vegetation types that burned in the fire. By opening the attribute table for this layer it showed ten different vegetation records, however, there are only six vegetation types. These vegetation types are Coastal Scrub, Desert Scrub, Juniper, Montane Harwood-Conifer, Pinyon-Juniper, and Urban-Agriculture. To merge the duplicate vegetation types, I used the Dissolve tool and thus concluded with an attribute table that showed the six vegetation types and the total area for each type that burned. Since the map projection being used in this project is the Universal Transverse Mercator Zone 11, measurements are all taken in meters. Our results, however, are supposed to be shown in acres, I found a website with a unit converter and converted all of the areas originally measured in square meters into acres.
In my analysis of the Willow Fire burn area in San Bernardino County, we can see that the total area of the burn site was 68,725 acres and consisted of various types of vegetation being affected by the fire. For the Urban-Agriculture vegetation type 2,052 acres were burned, which consisted of the smallest percentage of the total burn area, only about 3 percent. More significantly 21,974 acres of Pinyon-Juniper and 17704.8 acres of Desert Scrub burned in the fire, accounting for about 31 percent and 25 percent of the total burn area. It would make sense that Urban Agriculture would account for the smallest percentage of the burn site, since agriculture sites generally are well irrigated and thus could be protected better from fire damage. Desert scrub on the other hand is very dry and thus susceptible to fire. The other types of vegetation which burned in the fire were 9,655 acres of Coastal scrub accounting for 14.1% of the total burn area, 9,660 acres of Juniper which was also about 14.1% of the burn, and 7,678.3 acres of Montane Hardwood-Conifer which made up the remaining 11.2% of the fire. Ultimately we can see from the map and the analysis that it provides that there was a significant amount of damage caused by this fire. Since this area of San Bernardino County contains several vegetation types that are more flammable, such as Desert scrub and Pinyon-Juniper vegetation, fire in this area was able to spread quickly and burn tens of thousands of acres.
In my analysis of the Willow Fire burn area in San Bernardino County, we can see that the total area of the burn site was 68,725 acres and consisted of various types of vegetation being affected by the fire. For the Urban-Agriculture vegetation type 2,052 acres were burned, which consisted of the smallest percentage of the total burn area, only about 3 percent. More significantly 21,974 acres of Pinyon-Juniper and 17704.8 acres of Desert Scrub burned in the fire, accounting for about 31 percent and 25 percent of the total burn area. It would make sense that Urban Agriculture would account for the smallest percentage of the burn site, since agriculture sites generally are well irrigated and thus could be protected better from fire damage. Desert scrub on the other hand is very dry and thus susceptible to fire. The other types of vegetation which burned in the fire were 9,655 acres of Coastal scrub accounting for 14.1% of the total burn area, 9,660 acres of Juniper which was also about 14.1% of the burn, and 7,678.3 acres of Montane Hardwood-Conifer which made up the remaining 11.2% of the fire. Ultimately we can see from the map and the analysis that it provides that there was a significant amount of damage caused by this fire. Since this area of San Bernardino County contains several vegetation types that are more flammable, such as Desert scrub and Pinyon-Juniper vegetation, fire in this area was able to spread quickly and burn tens of thousands of acres.
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