| Abstrakt: |
Carbon storage and dynamics are receiving increasing attention because of the hypothesized role of CO2in global climate change. This study was carried out to determine total C storage in Lake States' forests, including C in biomass, forest floor, and mineral soil. Overstory trees were measured and samples of both forest floor and mineral soil (to 1 m) were collected from plots in 169 forest stands across Minnesota, Wisconsin, and Michigan. Five forest types were represented: balsam fir, Abies balsamea(L.) Mill.; jack pine, Pinus banksianaLamb.; red pine, P. resinosaAit.; aspen, Populus tremuloidesMichx.; and northern hardwoods dominated by sugar maple, Acer saccharumMarsh. There were no strong geographic trends in C storage in biomass, forest floor, or mineral soil across the study area. Storage differed significantly among forest types. Each major C pool was related to a different set of descriptors. Total C storage, the sum of all pools, was related to forest type, stand age, available water, actual evapotranspiration, and soil clay content, explaining about 65% of the variation. Use of soil and site descriptors did not completely account for the strong effects of forest type on C storage. Differences in the size of C pools, as related to time since disturbance and forest type, indicate that C storage in forests of the Lake States can be influenced by forest management activities. Patterns of C storage in these moist temperate ecosystems are not as strongly influenced by climatic variables as is C storage in grasslands to the west. |
Plný text