Regression equations applicable to biomass components of standsof western hemlock [Tsuga heterophylla (Raf.) Sarg.} were developedby destructive sampling of a thinned and an unthinned stand ofwestern hemlock near Seaside, Oregon. Equations predicted more live-branchbiomass and less dead-branch biomass per tree for the thinnedstand, but equations for biomass of foliage, twigs,...
Most soil organic C is in a stable form, associated with clay minerals in the upper soil profile. Upon environmental and land-use changes, stable soil C is subject to losses, which influence the global C cycle and the productivity of terrestrial ecosystems. However, mechanisms controlling soil C destabilization are not...
The detection and mapping of large scale changes to forested landscapes is increasingly important in ecology and management. I used Landsat TM and MSS imagery to map forest cover in 1992 for a 4.2 million ha area of the interior of British Columbia with an overall classification accuracy of 79%....
Study objectives were to survey and compare physical and chemical characteristics of soils within two thirdorder montane riparian ecosystems: a 500-year old Douglas fir (Pseudotsuga menzlesii) forest at Mack Creek, and a mature red alder (Alnus rubra) forest occupying a 35-year old clearcut at Quartz Creek, both near Blue River,...
I developed a conceptual model of Douglas-fir bark beetle dynamics and associated host mortality across spatial and temporal scales. I proposed that a hierarchy of factors influence host resistance to attack at different spatial scales. I then tested this model by measuring the association between the occurrence of beetle-kill and...
To increase our understanding of the timber harvesting behavior of family forest owners, I developed theoretical and empirical timber harvesting models for family forest owners in the southeastern United States. An individual-choice model was the basis for the models. Family forest owners were modeled as utility-maximizers who made harvesting decisions...
Dissolved organic matter (DOM) plays an important role in transport of C and essential nutrients such as N, P and S. DOM is also critical for the formation of soil organic matter (SOM), which is the largest terrestrial C pool. Nonetheless, we lack a basic understanding of what controls immobilization...
Maritime cyclonic windstorms cause widespread disturbance to forested ecosystems in southeast Alaska. The consequence of this disturbance process on the movement, storage, and quality of soil carbon, forest hydrology and streamwater chemistry was studied along a windthrow disturbance sequence. Soil profiles were described and the thickness of the major organic...
Application of N fertilizer is a common forest management practice in the Pacific
Northwest, yet the long-term influence of fertilization on forest soil properties is not well known. Although elevated N often increases mineralization of C and N from labile organic matter, negative effects have been documented in recalcitrant organic...
