The finding of increasing forest biomass over recent decades has proved remarkably controversial(cf for example Clark 2002; Lewis.
Phillips& Baker 2006. 2009b; Phillips et al. 2002a: wright 2005), despite the fact that an uptake of 2 PgC yr somewhere on Earth's land surface is evident from independ- ent mass-balance observations of the global carbon cycle.
While there is not space here to review the many early debates, the most persistent area of controversy can be characterised by the phrase'slow in, rapid out' (Korner 2003).
This argument stresses that forest growth is a slow process while mortality can potentially be singular in time, thereby causing rapid biomass loss and sometimes resetting forest stand structure. Consequently, limited sampling or sampling over short observation periods may tend to miss such more severe events.
Inferences based on such sampling could therefore result in positively biased estimates of aboveground biomass trends in old-growth forests when results from plot networks are extrapolated to a large are Given the still small number of tropical plots relative to the total biome area, this concern is understandable.
However, we suggest it is unlikely be a major source uncertainty or bias in our calculations for four reasons.
The finding of increasing forest biomass over recent decades has proved remarkably controversial(cf for example Clark 2002; Lewis. Phillips& Baker 2006. 2009b; Phillips et al. 2002a: wright 2005), despite the fact that an uptake of 2 PgC yr somewhere on Earth's land surface is evident from independ- ent mass-balance observations of the global carbon cycle. While there is not space here to review the many early debates, the most persistent area of controversy can be characterised by the phrase'slow in, rapid out' (Korner 2003). This argument stresses that forest growth is a slow process while mortality can potentially be singular in time, thereby causing rapid biomass loss and sometimes resetting forest stand structure. Consequently, limited sampling or sampling over short observation periods may tend to miss such more severe events. Inferences based on such sampling could therefore result in positively biased estimates of aboveground biomass trends in old-growth forests when results from plot networks are extrapolated to a large are Given the still small number of tropical plots relative to the total biome area, this concern is understandable. However, we suggest it is unlikely be a major source uncertainty or bias in our calculations for four reasons.
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