These effects on tree growth, which may persist for several decades (Hatchell et al. 1970, Butt 1987, Miller et al. 1996), may lead to shortand long-term reductions in tree growth and forest productivity. The level of soil disturbance will vary with soil texture, forest floor thickness, and soil water content at time of harvest (Miller and Sirois 1986, Corns 1988). In addition, machine type, si...

Determining how anthropogenic disturbances affect site productivity through bioassays requires a complete understanding of both overstory and understory vegetation. This study was installed in 1997 to determine how soil compaction and intensive harvesting affected the inherent site productivity of pine stands on the western boundary of loblolly pine’s (Pinus taeda L.) natural range. We measured...

We evaluated foliar and forest floor chemistry across a gradient of N deposition in the Northeast at 11 red spruce (Picea rubens Sarg.) sites in 1987/1988 and foliar and forest floor chemistry and basal area growth at six paired spruce and deciduous sites in 1999. The six red spruce plots were a subset of the original 1987/1988 spruce sites. In 1999, we observed a significant correlation betwee...

Exotic plants and river regulation have changed riparian ecosystems throughout the south-western U.S. We compared litter dynamics at sites dominated by native cottonwoods or exotic saltcedar in the Middle Rio Grande Valley of central New Mexico. Litter production was greater at cottonwood sites and may have increased after experimental flooding in cottonwood but not in saltcedar. Decomposition ...

In forested ecosystems, water soluble organics play an important role in soil processes including carbon and nutrient turnover, microbial activity and pedogenesis. The quantity and quality (i.e., chemistry) of these materials is sensitive to land management practices. Monitoring alterations in the chemistry of water soluble orgat~ics resulting from land management practices is difficult because...

The podzolic soils of the Kola Peninsula, Russia, have in localised areas been highly contaminated with copper and nickel from smelting activities. Migration and retention of these metals were investigated in undisturbed soil columns irrigated with simulated background and polluted precipitation in order to study the temporal processes of retention and release within the soil. The mineral layer...

Anthropogenic release of biologically available nitrogen (N) has increased dramatically over the last 150 years, which can alter the processes controlling carbon (C) storage in terrestrial ecosystems. In a northern hardwood forest ecosystem located in Michigan in the United States, nearly 20 years of experimentally increased atmospheric N deposition has reduced forest floor decay and increased ...

To investigate the dynamics and relative drivers of cellulose degradation during litter decomposition, a field experiment was conducted in three individual ecosystems (i.e., forest floor, stream, and riparian zone) of an alpine forest meta-ecosystem on the eastern Tibetan Plateau. Four litter species (i.e., willow: Salix paraplesia, azalea: Rhododendron lapponicum, cypress: Sabina saltuaria, an...

Little information has been available on the shifts in the microbial community in decaying fallen logs during critical periods in cold forests. Minjiang fir (Abies faxoniana) fallen logs in decay classes I-V were in situ incubated on the forest floor of an alpine forest in the eastern Tibet Plateau. The microbial community was investigated during the seasonal snow cover period (SP), snow thawin...

Soil incorporation of postharvest forest floor or logging residues during site preparation increased mineral soil carbon (C) and nitrogen (N) concentration and had a differential effect on early stand growth in a clonal loblolly pine (Pinus taeda L.) plantation. Incorporating 25 Mg ha 1 of forest floor (FF) (C/N ratio 112:1) or 25 (1LR) or 50 (2LR) Mg ha 1 masticated logging residues (C/N ratio...