Springer Old Growth Forests - Chapter 13 ppsx

... dominance of a shade-intolerant tree species contrasts with typical old- growth forests, older aspen forests do contain many typical old- growth attributes. Tree 13 Old Growth Forests in the Canadian ... the presence of old- growth forests. These should be taken into account in any regional assessment of the abundance of old- growth forests. 13. 3 Characteristics of...

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... 13) , is devoted to the old- growth forests of the Canadian boreal forest. Old- growth boreal forest is considered rare since disturbances occur too frequently to allow forest stands to reach old ... interaction for the functioning and main- tenance of old- growth forests. Second, they take a closer look at the peculiarities of nitrogen dynamics in old- growth forests unde...

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... Boreal old- growth forests were somewhat younger (median age 224 years, inter-quartile range 150 300 years), whereas tropical old- growth forests tended be older (median age 400 years, inter-quartile ... young old- growth forests are 6 0- to 120-year -old oak stands (Laiolo et al. 2003), a 100-year -old boreal Norway spruce stand (Dahlberg et al. 1997), and a 110-year -old...

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... Wirth Chapter 3 Old Trees and the Meaning of Old Fritz Hans Schweingruber and Christian Wir th 3.1 Introduction While the mere presence of old trees does not automatically indicate old- growth ... are generally shorter-lived than trees (Schweingruber 1995) and dwarf-shrubs (see below). The oldest known shrub s grow in Siberia. Hantemirov et al. (2003) found an 840-year -old Juniperus...

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... decrease in net primary productivity in old- growth forests if it occurs is related more to decreasing photosynthesis in old and tall trees (as well as in old- growth forest canopies) than to increasing respiratory ... shifts compen- sated each other such that relative growth rates were similar across the shade- tolerance gradient, while our results suggest higher growth rates f...

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... 20 1- to 400-year -old stands (early old- growth) are either carbon-neutral or still accumulating carbon. Few successions exhibited a pronounced late-successional decline. These results are consis- tent ... progressing from early- to late-successional conifers, and from early-successional hardwoods to late-successional conifers, tended to accumu- late carbon during the early old- gro...

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... Comparisons with second -growth forests are also often made to highlight the uniqueness of old- growth forests. 6.2 Structural and Compositional Features of Old- Growth Old- growth forests possess distinct ... environment in old- growth forests, (2) the particular understorey light condi- tions found under such forests, and (3) the unique understorey vegetation assem- bla...

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... of old- growth forests are expected to influ- ence biosphere atmosphere exchange of such forests. In this chapter we will focus on structural features of old- growth, i.e. the fact that old- growth ... multi-y ear calibration periods. In this chapter, we summarise results from studies in old- growth forests across the globe in order to (1) describe structura l characteristic...

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... reduction in NPP or an increase in decom- position rate-constants as forests age could lead to mid-successional forests having more woody detritus than old- growth forests. Repeated disturbance was ... decomposition rate-constants (Olson 1963). In general, as the NPP of old- growth forests increases, the live biomass, and the input of mortality increases. Thus, more productive...

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... (Brais et al. 1995; De Luca et al. C. Wirth et al. (eds.), Old Growth Forests, Ecological Studies 207, 193 DOI: 10.1007/978‐3‐540‐ 92706‐8 9, # Springer Verlag Berlin Heidelberg 2009 2002). This is ... relatively fast-growing early-successional species such as Pinus sylvestris and Vaccinium myrtillus, and the middle-sized islands are dominated by Betula pubescens and Vaccinium vitis-idaea...

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