This study has analyzed factors which affect the accumulation of terrestrial organic debris within natural gravel streambeds. In
addition, the amounts, sizes, and physical conditions of intruded material were measured, along with the effect of the detritus on intragravel dissolved oxygen levels. Measurements indicate that aged intragravel detritus had no...
The atmospheric trace element abundances associated with slash
burning have been measured by instrumental neutron activation analysis
(INAA). On site ground level samples were collected during the slash
burning season using high volume samplers and a cascade impactor. In
addition to the air samples, soil, wood and ashed wood samples...
A log step develops when large woody debris extends across the active
channel, creating a change in the water surface elevation as the stream
spills over the log step. By forming a series of vertical falls, log
steps reduce the amount of potential energy available for conversion to
kinetic energy...
Amounts of natural debris in small headwater streams under old growth
stands of Douglas-fir vary from 6 1/2 tons per 100 ft. of stream
to 26 tons per 100 ft. of stream, depending on terrain and timber
characteristics and sequence in the natural accumulation-flushing
cycle. Approximately 10% of the weight...
A series of stereo photographs displays a range of residue loadings for cleancut units in three general forest types common to coastal Oregon forest lands: Douglas-fir--western hemlock (second-growth), western hemlock--Sitka spruce, and red alder. Postburn residue levels are also represented for the Douglas-fir--western hemlock, and red alder types. Information with...
Riparian vegetation (trees > 10 cm dbh), woody debris (> 10 cm diam, > 1 m long), channel, and landform characteristics were inventoried in mature (80-150 yrs) and old-growth riparian areas (>250 yrs) selected from small tributaries of the Coos and Coquille River basins in southwestern Oregon. Basal area of...
In order to decide whether or not to develop biomass energy facilities and where to best locate them, developers and investors need accurate assessments of fuel supply. This includes information about the distribution and concentration of fuel throughout the assessment area, the quality of fuel (form, moisture content, contaminant content,...
Thinning to reduce hazardous fuels often generates large amounts of woody residues, such as small-diameter logs, tree
tops, and branches. This publication discusses
several options for economically and effectively
using and disposing of woody material.
The scientific literature on logging after wildfire is reviewed, with a focus on environmental effects of logging and removal of large woody structure. Rehabilitation, the practice of planting or seeding after logging, is not reviewed here. Several publications are cited that can be described as 'commentaries', intended to help frame...
The objective of this study was to quantitatively describe the intrusion of logging debris into artificial gravel streambeds during conditions of low stream flow with a stable streambed, and begin an
analysis of the effect of high flow and unstable streambeds. This study was initiated because prior studies indicated that...
This study investigated the long-term consequences of timber stand removal on the recruitment, physical characteristics, and
spatial distribution of coarse woody debris in small (second- and third-order) streams of the Oregon Coast Range. A chronosequence of stream-stand systems, ranging from 21- to 140-years since disturbance (YSD), were sampled to determine...
Moisture content management is a key requirement to improve forest harvest residue economics for bioenergy production. This dissertation aims to contribute towards better management through these three general objectives (1) Determine average moisture content of fresh forest harvest residues and its changes over the different seasons of the year, focusing...
An economic analysis and optimization of forest biomass processing and transportation at the operational level is presented. Renewable sources of energy have captured the interest of public and private institutions to develop cost-effective supply chains to reduce dependence on fossil fuels. The production of energy from forest harvest residues constitutes...
Previous research has indicated that considerable amounts of finely divided slash accumulate in small mountain streams following timber harvesting. The subsequent biological decomposition of this organic matter can result i.n the reduction of dissolved oxygen (DO) concentration to levels as low as 0.6 ppm. These DO levels are lethal
to...
Growing societal demand for forest products is pressuring managers to increase productivity from a finite land area, and it is expected that increased supply will come mostly from expansion of intensively managed stands. The USDA Forest Service and numerous collaborators created the Long-Term Soil Productivity (LTSP) network of research sites...