| Dendroindication of land use dynamics |
| Paper ID : 1075-ADA2013 |
| Authors: |
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Kirill N. Diakonov1, Tatiana Kharitonova *2 1MSU Leninskie gory, Moscow 2119991 Leninskie gory, Lomonosov MSU, GSP-1, Department of Geography |
| Abstract: |
| Dendrochronology as a reflection of the whole ecosystem annual productivity serve as a confident indicator of landscape dynamics. In order to determine influence of fen drainage, its cultivation, further abandonment and secondary swamping on adjacent forested territory, tree ring sampling of Norway Spruce (Picea abies) and Scots Pine (Pinus sylvestris) was performed at the sites which corresponded to various relief levels and distance from the drained fen and at similar geosystems which were not influenced by drainage. Research was held in Meschera lowland, Russia (55,3N, 40,2E). Hypothesis was that anthropogenic impact would come apparent at middle frequency fluctuations of chronologies. So two-step tree ring standardization was undertaken to devide chronologies into three components – low frequency described by stiff spline function with a 50% frequency cutoff in 50 years, middle frequency described by same function with a cutoff in 11 years and high frequency described by remains after detrending. Middle fluctuation curves show high synchrony among all sites, which means all territory dependence on same set of factors. Climatic factors influence was revealed by means of forward stepwise regression with reliable R2 from 0,34 to 0,69: Spruce middle frequency fluctuations showed dependence on april temperature, winter-summer amplitude of middle temperatures and winter precipitation, while Pines - on summer precipitation and may moisture index. Endogeneous factors and anthropogenic impact are responsible for the rest fluctuations. Predicted curves show less variation then observed, difference in variation is most prominent at drained sites, which proves its instability owing to amplification of a climatic signal. The highest instability of curves is recorded in period of drainage which in addition to unfavourable climatic conditions resulted in considerable increment decrease at all drained sites. Ecosystem adaptation to new moist conditions was finished in a period of approxomately 12 years for Pine stands, neither further renovation of drainage, nor abandonment and secondary swamping didn't effect Pine increment fluctuation. Spruce stand dynamics still differs in drained and indigenous sites though territory secondary swamping proceeds during last 20 years. |
| Keywords: |
| dendroindication, drainage, abandonment |
| Status : Abstract Accepted |
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