A 7000-Year Record of Environmental Change, Bear Lake, Rocky Mountain National Park, USA
A 7000-Year Record of Environmental Change, Bear Lake, Rocky Mountain National Park, USA
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7000 年环境变化记录，美国落基山国家公园熊湖
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
James P. Doerner
中科院分区：
文献类型：
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作者：
M. Caffrey;James P. Doerner
关于落基山国家公园火灾历史的长期记录很少。从湖泊沉积物芯的数据被用来重建在过去的7000卡年的植被和火灾频率的变化。熊湖是位于科罗拉多落基山国家公园的一个高海拔湖泊，周围环绕着亚高山植被。花粉资料表明，一个温暖和干燥的气候占主导地位之间的约。7000和5000 cal年BP。气温上升，直到不久前约。3500 cal/yr BP时，发现明显下降的证据。比现在更冷的条件下保持，直到约。1700 cal yr BP，当条件过渡到更像今天的气候。根据宏观木炭分析，火灾频率在每1000年2到5次之间。木炭中的最大峰在约。590 cal yr BP.火灾复发间隔随时间的气候变化而变化;然而，我们计算出在过去7000年中火灾复发间隔为325年。鉴于这些结果，根据政府间气候变化专门委员会目前对年气温上升的气候预测，火灾活动可能会增加。
Few long-term records of the fire history of Rocky Mountain National Park exist. Data from a lake sediment core was used to reconstruct changes in vegetation and fire frequencies over the last 7000 cal yr. Bear Lake is a high-elevation lake surrounded by subalpine vegetation in Rocky Mountain National Park, Colorado. Pollen data indicate that a warm and dry climate prevailed between ca. 7000 and 5000 cal yr BP. Temperatures increased until shortly before ca. 3500 cal yr BP when evidence for a marked decline is seen. Cooler-than-present conditions were maintained until ca. 1700 cal yr BP, when conditions transitioned to more like those of the present-day climate. Based on macroscopic charcoal analyses, fire frequency had varied between two and five episodes per 1000 years. The largest peak in charcoal was at ca. 590 cal yr BP. The fire return interval has varied with climate over time; however, we calculate a fire return interval of 325 years over the past 7000 years. Given these results, fire activity is likely to increase under current Intergovernmental Panel on Climate Change climate projections of an increase in annual temperatures.