Differences in time and space in vegetation patterning: analysis of pollen data from Dartmoor, UK

作者：Fyfe Ralph M^*; Woodbridge Jessie

来源：Landscape Ecology, 2012, 27(5): 745-760.

DOI：10.1007/s10980-012-9726-3

• Pollen
• Charcoal
• Heterogeneity
• Burning
• Fire
• Moorlands
• Spatial analysis
• Palaeoecology
• Dartmoor

Moorlands perform a wide variety of roles within modern society. A vital component of these landscapes is the patterning of vegetation, and management of this requires a thorough understanding of the drivers of vegetation change. Although there has been a considerable body of research focussed on the processes that are important in patterning contemporary vegetation these typically lack any significant time-depth. Long-term data, using palaeoecological techniques, offer insights into drivers of vegetation change that are otherwise unachievable. This paper presents new palaeoecological data from Dartmoor (UK) to test two hypotheses: (1) that vegetation character of moorland is spatially homogenous through the past 8,000 years; and (2) that burning has a significant role in the development of open, grass-dominated, vegetation. Four peat cores spanning the past 8,000 years were subject to pollen and microcharcoal analysis. Thirty-seven radiocarbon age estimates were obtained to determine age-depth models for the pollen and charcoal stratigraphies. Differences within and between the pollen stratigraphies have been used as an indirect measure of landscape heterogeneity at a coarse scale. The data reveal periods of time during which differences in the vegetation (as sensed by pollen) around each site are small, and periods during which differences between vegetation are large. Periods of time characterised by greater spatial difference, and by inference greater heterogeneity, correlate with periods characterised by greater human exploitation of the landscape as revealed by archaeological evidence. Human activities therefore promote greater spatial patterning in the landscape. Fire alone is not an important control on long-term peatland vegetation development. The results are useful for conservation strategies by demonstrating variability in spatial diversity of vegetation patterns in the past, and pointing towards opportunities to recreate and maintain diverse vegetation mosaics.

• 出版日期2012-5