Ryegrass residue consists of three main C fractions: readily available soluble C, intermediately available cellulose and hemicellulose, and slowly available lignin. Changes in chemical composition during decomposition influence rate of degradation as well as composition of the microbial community involved. Use of ¹³C-labeled plant material coupled with analysis of phospholipid...
Field-plot experiments and pot culture techniques were used to
investigate reported Cu deficiency in certain Oregon organic soils.
Field experiments were established in 1973 and 1974 on an acid peat
soil and two alkaline muck soils near Klamath Falls, The effect of
rates of from 0 to 45 kg Cu/ha...
Copper deficiency and Mo-induced Cu deficiency are nutrition
problems of ruminant livestock in the Burns and Klamath Falls area
of Oregon. Chemical analysis of plant and soil samples was used to
survey Cu and Mo levels in forage in these areas. The objectives
were to assess the possibility of animal...
As part of a participatory research project, where farmers and Oregon State University researchers collaborated, aspects of potato (Solanum tuberosum L.) growing systems were studied. It was determined through conversations with the farmers that quantification of certain growth parameters of potato was lacking, including dry matter accumulation, crop nitrogen (N)...
The mechanisms governing short- and long-term belowground carbon dynamics need to be understood. As part of a larger project developed to assess the effect of quantity and quality of litter inputs on the rate of soil organic matter (SOM) formation, I examined SOM in the H. J. Andrews Detritus Input...
Interest in measuring soil quality continues to increase worldwide in view of demands on land productivity and the necessity to preserve soil resources, yet identification of suitable indicators for soil quality assessment is still evolving. This study adapted 10 biological, physical, and chemical indicators of soil quality identified by the...
Forest harvest can have significant impacts on forest ecosystems that may influence the capacity of soils to sequester carbon (C). The microbial community controls decomposition, which is a critical process in partitioning litter- and root-C between CO₂ and storage in semi-permanent soil-C pools. The objectives of this study were to...
Soil erosion by mass wasting is the major problem on forest
lands of the Pacific Northwest, The clay fractions of soils from a
large number of sites in Oregon's Western Cascades were characterized
in order to determine the relationships of various clay materials to
mass movements. Each site was either...
In arid and semi-arid deserts, soils are commonly covered with biological soil crusts. The
study of arid biocrusts and their ecological function has become increasingly common in
the literature over the last several decades. Interestingly, no mention is made of
biological soil crusts in forested ecosystems, raising the question as...