Springer Old Growth Forests - Chapter 18 ppt

... et al. (eds.), Old Growth Forests, Ecological Studies 207, 411 DOI: 10.1007/978‐3 ‐540‐ 92706‐8 18, # Springer Verlag Berlin Heidelberg 2009 year between 1990 and 2005 (non-intact forests have ... deforestation is take n as changes from intact and non-intact forests to non -forests. The change rates from intact forests to non-intact forests are approximated by applying a ratio o...

Ngày tải lên: 03/07/2014, 13:20

... 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...

Ngày tải lên: 03/07/2014, 13:20

... 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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... forest use. 20.3 Consideration of Old- Growth Forests in UN Processes 20.3.1 Old- Growth Forests and the UN Framework Convention on Climate Change Old- growth forests are usually characterised by ... in their forests, including old- growth forests. But if old- growth forests are considered ‘‘unmanaged’’ they are excluded from the UNFCCC and the Kyoto Protocol, because...

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... 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 under the low levels of nitrogen ... protection of old- growth forests, and present an encouraging example. Finally, Grace and Meir (Chap. 17) close this part with a chapter on old- growth dynamics in globa...

Ngày tải lên: 03/07/2014, 13:20

... of forests that were labelled as old- growth . Altogether we identified 118 studies where ages of old- growth forests were reported, half of which were temperate or high-elevation coniferous forests and ... 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 -o...

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... the mere presence of old trees does not automatically indicate old- growth conditions (see Chap. 2 by Wirth et al., this volume), it is fair to say that many old- growth forests contain a high ... 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...

Ngày tải lên: 03/07/2014, 13:20

... 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...

Ngày tải lên: 03/07/2014, 13:20