The theoretical approach of ecoplexivity focusing on mass outbreaks of phytophagous insects and altering forest functions

Anne le Mellec¹*, Jerzy Karg², Jolanta Slowik³, Ignaczy Korczynski⁴, Andrzej Mazur⁴, Timo Krummel¹, Zdzislaw Bernacki³, Holger Vogt-Altena¹, Gerhard Gerold¹ and Annett Reinhardt¹

¹Landscape Ecology Section, University of Göttingen, Goldschmidtstr 5, D-37077 Göttingen, Germany.

²Research Centre for Agricultural and Forest Environment, Polish Academy of Sciences, Field Station Turew, Szkolna 4, Pl-4-000 Kościan, Poland.

³Centre for Nature Conservation (CNC), University of Göttingen, von Sieboldstrasse 2, D-7075 Göttingen, Germany.

⁴Department of Forest Entomology, Poznan University of Life Sciences, Ul Wojska Polskiego 71c, PL-60-637 Poznan, Poland.

*Corresponding author. E-mail: amellec@gwdg.de. Tel: (+49) 0551-3912134.

Accepted 30 November, 2009

 Abstract

Epidemics of forest insects can have deep impacts on ecosystem functioning and dynamics, with consequences for forest economics and forest carbon feedback to climate change. Despite the many roles that insects fulfil in terrestrial ecosystems, their importance in nutrient cycling is not well known (Kosola et al., 2001). The only instances where herbivores are recognized to have a large effect on ecosystem function are mass outbreaks of particular species like herbivores. However, the climate change induced alterations in precipitation and temperature patterns will undoubtedly affect occurrence, intensity, frequency, magnitude and timing of these phenomena and thus, provoke an increasing susceptibility of hosts and a significantly larger habitat presence of pests. Records show that, in an increasing number of cases severe outbreaks can even cause the complete devastation of vast areas and thus, imply considerable economic losses at a large scale. Down to the present day, it remains uncertain how forest ecosystems will respond to the changing environmental conditions in the long run. This work reports on the possible alterations of forest functions due to mass outbreaks of phytophagous insects with respect to the changing ecosystem service of carbon sequestration ability of forests on the northern hemisphere.

Key words: Forest disturbances, insect mass outbreaks, forest functioning, carbon sequestration.