Graduate Thesis Or Dissertation
 

Effects of spatially dispersed green-tree retention on ectomycorrhiza diversity

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/w9505305w

Descriptions

Attribute NameValues
Creator
Abstract
  • The Demonstration for Ecosystem Management Options (DEMO) study originated out of the changing management priorities associated with federal forest lands in the Pacific Northwest which included an objective to maintain mature and old-growth forest characteristics in managed stands. The DEMO project examines the effects that different levels and patterns of green tree retention have on various aspects of biodiversity including the diversity of ectomycorrhizal fungi (EMF). Ectomycorrhizal fungi play an important functional role in forest ecosystems. Ectomycorrhizal fungi are essential for nutrient uptake by the host tree, they have been shown to play a critical role in forest regeneration success, and EMF provide an important food source (in the form of sporocarps) for many small mammals. As part of the DEMO study, this thesis documents EMF diversity in the control unit (100% retention) and the spatially dispersed 40°/a basal area retention treatment (40%D). The measures of diversity studied included EMF constancy, abundance, and species richness. Constancy and abundance measures were analyzed only for the common ectomycorrhizae (EM) types. Morphological techniques for identification of the EMF were employed together with molecular techniques to achieve the finest level of identification possible. Characters used to assess morphology include mantle structures, emanating hyphae, rhizomorphs, root morphology, chemical reactions, and mantle color. Molecular techniques were used for identification purposes and for checking EM morphotype groups. Molecular techniques used included DNA extraction of the internal transcribed spacer region, polymerase chain reaction amplification, restriction fragment length polymorphism, and DNA sequencing. Significant responses to the 40%D treatment were determined by testing both pre and post EMF diversity within the treatment and by comparing changes in diversity between the control and the 40%D treatment. Overall, within the 40%D treatment, the majority of the common EMF species did not decrease significantly. A moderately significant difference was detected between the pre-treatment and post-treatment mean number of EM types per soil core (measure of species richness). This decrease in richness of about 50% in the post-treatment2 samples seems to indicate a delayed response to the treatment since the post-treatment1 samples were not different from the pre-treatment conditions. Since no dominant types were lost, the decline in richness occurred in the less common EM types. This research demonstrates that the 40%D treatment can maintain a relatively high legacy of EMF. However, there is a loss of some rare EM types and a reduction in abundance and constancy in some of the more common EM types. These results lend support for the consideration of40% dispersed green-tree retention as a silvicultural option when management goals include the maintenance of EMF diversity. Timber harvest via implementation of ecosystem-based forest management practices will require the continuing study of complex below-ground systems for the development of potential silvicultural treatments during further iterations of adaptive management.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Language
Digitization Specifications
  • PDF derivative scanned at 300 ppi (256 B&W), using Capture Perfect 3.0, on a Canon DR-9080C. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details Kolaczkowksi_Oralia_2005.pdf 2017-08-08 Public Download