Readers who are interested in more details of the general theory and empirical studies of forest decline and soil acidification please consult this paper:
by Lee Klinger MA PhD
Presented at: Treework Environmental Practice Seminar XIII
Linnean Society, Burlington House, London, UK – 30th June 2009
Forest communities are complex systems comprised of populations of organisms representing every kingdom of life – plants, animals, fungi, protists, and monists – living and growing together on the land. They are part of a larger group of communities that constitute the regional ecosystem, or landscape. Forest communities are developmentally related to the surrounding communities in ways that can be characterized through chronosequence studies. Chronosequences from southeast Alaska and subarctic Canada are described and interpreted as indicating that, while early successional processes facilitate forest growth and productivity, later successional processes tend to slow and inhibit forest growth and regeneration. In many places forests are seen to have transitioned into peat bogs over the course of several thousand years. This is thought to reflect the true climax nature of bog ecosystems.
Forest to bog transitions are linked to two main developmental processes: podzolization and paludification. Podzolization affects many northern forests and involves the translocation of iron, aluminium, clays and organic compounds in response to vegetation, especially mosses, acidifying and leaching the soils. This is often followed by paludification, which occurs as peat-forming mosses, such as Sphagnum species, become established and expand.
From the perspective of succession, forests are seen to flourish under early successional conditions, conditions that are enhanced by periodic or regular disturbances. However, where disturbances are eliminated, forests begin to show decline as a consequence of natural successional changes. This work points to the potential for managing forest ecosystems through the maintenance of disturbance regimes and the remediation of acidification tendencies in the vegetation and soils.
Download the complete paper here.