Document: EUG-3-59-27

Soil respiration at dominant patch types within a managed landscape in northern Wisconsin.

EUSKIRCHEN, E.* ¹, J.CHEN ¹ and E.J.GUSTAFSON ²

Michigan Technological University, Houghton, MI 49931 USA ¹
USDA Forest Service, Rhinelander, WI 54501 USA ²

Abstract:
Soil respiration was measured during the 1999 growing season within three replications each of six dominant patch types in a managed landscape. CO₂ evolutions (SRR) were quantified using an infra-red gas analysis system. Readings of photosynthetic active radiation (PAR), soil moisture (% dry weight), and soil temperature (5cm and 10 cm below surface) were taken at the time of each SRR measurement. These data were then used to derive respiration-temperature-moisture models for each patch type. Clear differences in soil respiration between the patch types were observed. Mature and young hardwoods had the highest values (1.1 to 1.9g CO₂ /m²/hour), red and jack pine plantations had a moderate SRR (0.92 to 1.4 g CO₂ /m²/hour) while pine barrens and clearcuts had the lowest (0.47 to 0.79 g CO ₂ /m ²/hour). Soil temperature best explained the variation in soil respiration within the pine barrens patch type (56% of variation). Soil moisture explained between 10-20% of the variation within all patch types. Results from empirical models will help us to predict the cumulative SRR of the overall landscape and assess landscape responses to potential climate change.

Keywords: soil respiration, managed landscape, empirical models

This abstract is being presented at: 10:30 AM in session:
Poster Session #13: Decomposition and Soil Respiration.