, 2007 and Staland

et al., 2011). Hence, it is important to acknowledge past human impact even in areas that are considered as undisturbed; old cultural landscapes include much more than the well mTOR inhibitor known examples from central Europe ( Behre, 1988) as well as from other parts of the world (e.g. Briggs et al., 2006), although the processes behind each ecosystem change may differ significantly. Only by adopting a long-term perspective it is possible to evaluate and understand land-use legacies even in remote ecosystems considered as “natural” today ( Willis and Birks, 2006). An inability to reconstruct historical land use may skew perspectives on what is considered to be a natural or semi-natural landscape. The lack of recent or recorded disturbance is often used as a metric Tofacitinib nmr for ascribing naturalness. The notion that open spruce-Cladina forests of northern Sweden are a natural forest type is challenged by the findings provided herein. Charcoal and pollen in mire stratigraphy samples and the evidence of semi-permanent dwellings demonstrate vegetative shifts that correspond with dating of hearth use point to a human fingerprint on

the establishment of this open forest type. Recurrent use of fire to manage stand structure and understory composition led to a decline in nutrient capital on all three sites which in turn provided insufficient resources for the regeneration of Norway spruce, feathermoss forest types. Nitrogen resources in the O horizon of the degraded spruce-Cladina forests represent less than 10% of that in the reference forests and represent inadequate N resources required to sustain the biomass associated with the reference forests. Further, the loss of juniper from the understory may have eliminated an important ecosystem component which normally protects young seedlings from

browse and trampling and provides resources 4-Aminobutyrate aminotransferase and protection for N2 fixing feathermosses regeneration. The dominance of Cladina in the understory further eliminated the potential for recapture of N resource for seedling growth and regeneration combined with the relatively low resource demand of slow growing Norway spruce led to the perpetuation of an open stand structure and minimal organic soil nutrient resources. Landscape analyses that integrate historical human activities with paleoecological and ecosystem evidence proved necessary to accurately characterize the naturalness of the spruce-Cladina forests of northern Sweden and serves as an example of how ancient land use can greatly influence what we see on the landscape today and what is viewed as natural. The authors wish to thank the European Regional Development Fund and the Bank of Sweden Tercentenary Foundation for their financial support of this project. We also thank Ms. Sarah Chesworth for her assistance with laboratory analyses.

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