This study examined how annual bedload export volume and bedload characteristics were related to disturbances including logging, floods, debris slides, and wildfires over 48 to 65-year periods in small, steep catchments in conifer forests of the western Cascade Range, Oregon. Bedload – the material rolling, sliding, or saltating along the...
Streams and rivers play a critical role in global carbon (C) cycling by processing, storing, and transporting C. Headwater streams which make up more than 95% of the length of streams and rivers worldwide have disproportionate influence on fluvial C dynamics. The hyporheic zone (HZ) of headwater streams is a...
We present a systems modeling approach to the development of a place-based ecohydrological model. The conceptual model is calibrated to a variety of existing observations, taken in watershed 10 (WS10) at the HJ Andrews Experimental Forest (HJA) in Oregon, USA, a long term ecological research (LTER) site with a long...
Population trends and patterns in species distributions are the major currencies used to examine responses by biodiversity to changing environments. Effective conservation recommendations require that models of both distribution dynamics and population trends accurately reflect reality. However, identification of the appropriate temporal and spatial scales of animal response, and then...
Field and laboratory studies are being conducted to describe the hydrologic properties of soil and to determine the timing pathway of precipitation and snowmelt water as it moved through forested soil on a steep slope. Hydrologic properties include hydraulic conductivity, porosity, pore-size distribution, moisture characteristics, stone content, and soil depth....
Most carbon (C) transformations in soil are carried out by a diverse and complex soil microbial community. The size and composition of the soil microbial community is determined by poorly understood interactions between the quantity and chemical composition of plant inputs, as well as climate. Given the metabolic diversity of...
This report describes decomposition studies conducted in the H. J. Andrews
Forest, Oregon in 1973. Changes in weight loss and nutrient content of
leaves, cones, branches, and bark of Douglas-fir and leaves of big-leaf
maple, vine maple, Rhododendron, red alder, sword fern Oregon oak, and
Chinkapin were recorded in a...
Air temperatures at i m and soil temperatures at 2C cm are reported for
twenty-one forest stands in the central Western Cascader of Oregon. Records
began in 1970 for some stands, in 1971 or 1972 for most. Temperature Growth
Index for a stand, based on temperature effects on Douglas-fir seedling...
A total of 23 forest communities have been identified and characterized in a preliminary manner. Data used in formulating the classification had previously been collected on 300 reconnaissance plots located on the
H. J. Andrews Forest and surrounding area. Vegetation classification was facilitated by similarity analysis and stand ordination procedures...
Sediment yield increases following timber harvest and road construction
were predicted for four Pacific Northwest experimental
watersheds. Sediment yields were predicted using a handbook developed
by the U.S. Forest Service entitled, "An Approach to Water Resources
Evaluation of Non-Point Silvicultural Sources" (WRENS). Predicted
sediment yield increases varied from 40 to...