ausblenden:
Schlagwörter:
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Zusammenfassung:
Forests are a major and diverse land cover occupying a third of the terrestrial vegetated
surface; they store 50 to 65% of terrestrial organic carbon (including the soil) and contribute
half to terrestrial productivity. Forest biomass stores close to 80% of all the biomass
on Earth. As noted earlier, forests play an important role in the Earth system as carbon
stocks, carbon sinks, mediator of the water cycle and as modifier of land surface roughness
and albedo. Moreover, forests play a role as habitat for many species, are an economic
source of timber and firewood and have recreational value for local populations and touristic
visitors. Here, we appraise how ecosystem functions are influenced in particular by biomass
and its vertical and horizontal distribution and hypothesize that almost all functions
are directly or indirectly related to biomass, in addition to other factors. At landscape or
regional scale, heterogeneity of biomass presumably has an important influence on a variety
of processes, but there are gaps both in quantifying the heterogeneity of forests globally
and in quantifying the effect of this heterogeneity. Similarly, while the role of forests for
the global carbon cycle is important, large uncertainties exist regarding stocks, turnover
times and the carbon sink function in forest, as an analysis of state-of-the-art carbon cycle
and vegetation models shows. Upcoming global satellite missions such as GEDI, NISAR
and BIOMASS will be able to address the above uncertainties and lack of understanding in
combination with modeling approaches, in particular by exploiting information on vertical and horizontal heterogeneity.
