The Necessity of Fire to Preserve: A History of the Albany Pine Bush Pine Barren using Sedimentary Charcoal and Pollen
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Pine barrens are an ecosystem type unique to North America that developed following deglaciation and contain many rare species of fauna and flora. They are fire-dependent ecosystems because both their species compositions and their reproductive cycles rely on the regular disturbance of wildfire. The Albany Pine Bush is the best intact inland pitch pine-scrub oak barren in the Northeastern United States. After many years of land development and fire suppression, this unique landscape was in danger of disappearing. In 1988 a preserve area was established to maintain and expand the pitch pine-scrub oak barrens whose management included prescribed fire as a necessary disturbance. A better understanding of the fire history of the area is needed to understand its natural fire cycle to inform future fire management decisions. Sediment core micro-charcoal analysis is a recently developed field of paleoecology which uses the accumulation rate of micro-charcoal in lakes and peat bogs to reconstruct local fire histories. Charcoal analyses are often studied alongside other fire proxies to corroborate the fire history and pollen records are especially useful since they indicate fuel availability and the relationship between fire frequency and vegetation succession. Previously, there has not been a high-resolution paleo-fire analysis of this pine barren. For this study I completed a fire history reconstruction of the Albany Pine Bush barren using sediment core micro-charcoal and pollen from the early Holocene to present day. Evidence of frequent fire events were found consistently throughout two lake and peatbog sediment cores spanning the last 12,000 years, giving average fire return intervals (FRIs) of 488 and 494 years for the respective cores. Because of the Nyquist frequency and the sampling intervals used, these results are the highest frequency FRIs that are detectable. The results of the pollen analysis show the consistency of the pine and oak, and therefore the long establishment of the pine barren here. The results also indicate a shift in the surrounding vegetation from boreal to deciduous forest ~10,000 BP which is consistent with similar pollen studies in the region. Hence, my results suggest that fires have been a consistent disturbance in this pine barren since its establishment after deglaciation in the early Holocene.