Chapter 21 Old-Growth Forests: Function, Fate and Value – a Synthesis The total number of scientific articles on old-growth forests has increased drastically over the last 10 years (Chap. 2 by Wirth et al.), and yet papers on old-growth forests make up only about 1% of all forest- or forestry-related articles listed in the Web of Science. | Chapter 21 Old-Growth Forests Function Fate and Value - a Synthesis Christian Wirth Challenges in Functional Old-Growth Forest Research The total number of scientific articles on old-growth forests has increased drastically over the last 10 years Chap. 2 by Wirth et al. and yet papers on old-growth forests make up only about 1 of all forest- or forestry-related articles listed in the Web of Science. The availability of process information as reviewed in this book decreases exponentially with stand age irrespective of the ecosystem function considered Fig. . One likely reason for the scarcity of information on old-growth forests is their seemingly low economic relevance and consequently limited research funding. Another possible reason is the scarcity of old-growth forests themselves in the countries where most scientific research is carried out. Surely this may be compensated for by the fact that rarity tends to spark interest. Like anyone else ecologists are fascinated by tall majestic forests. This is clearly reflected by the dominance of old-growth studies carried out in the famous temperate rainforests of the western United States. However the same features that make old-growth forests attractive tall trees complex structure organismic diversity remoteness pose tremendous challenges to ecosystem research. Old trees are usually tall and access to the canopy requires expensive infrastructure such as canopy cranes or towers not to mention the difficulties involved in studying root systems. Old-growth forests are highly heterogeneous in both the vertical and horizontal dimensions. Spatial heterogeneity in soil conditions is caused by tree falls Chap. 10 by Bauhus . Thus soil sampling aimed at a reliable estimate of element stocks and fluxes requires a large number of spatial replicates Chap. 11 by Gleixner et al. . To complicate matters further mere soil sampling is not sufficient to quantify ecosystem processes such as mineralisation or heterotrophic .
