• Login
    View Item 
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Older Theses Not Clearly Affiliated with a Current College
    • View Item
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Older Theses Not Clearly Affiliated with a Current College
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Scholarworks@UACommunitiesPublication DateAuthorsTitlesSubjectsTypeThis CollectionPublication DateAuthorsTitlesSubjectsType

    My Account

    Login

    First Time Submitters, Register Here

    Register

    Statistics

    Display statistics

    Seasonal Patterns Of Nitrogen Mineralization And Nitrification Following Harvesting In The White Spruce Forests Of Interior Alaska

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Gordon_A_1986.pdf
    Size:
    6.290Mb
    Format:
    PDF
    Download
    Author
    Gordon, Andrew Maclean
    Keyword
    Forestry
    Metadata
    Show full item record
    URI
    http://hdl.handle.net/11122/9287
    Abstract
    The effects of commercial timber harvesting upon nitrogen transformations were evaluated for the forest floor and mineral soil of mature white spruce (Picea glauca (Moench.) Voss) forest sites in interior Alaska. Analyses of forest floor and mineral soil incubated in situ in mature forest and two recently harvested areas of different ages indicated an ammonium-dominated soil system for the unharvested area. Statistically, logging had no effect upon mineralization, nitrification or on the average NH(,4)-N or NO(,3)-N produced on incubation in the forest floor. In the mineral soil the same patterns were apparent with the exception that the NO(,3)-N produced on incubation was significantly greater in the harvested areas. However, the lack of a large number of incubation periods (n = 8), over the entire course of study (22 months of continuous incubation) likely contributed to this result. While mineralization (ammonification) rates did not differ between areas, there were times in mid-summer when nitrification rates in the clearcut areas far exceeded those in the control area. Thus, although the net amount of NH(,4)-N produced was not different between areas, the amount of nitrogen moved from the organic pool into available pools (net nitrogen mineralization) was greater in the harvested areas, primarily because of mid-summer nitrification in the latter. Increased soil moisture and temperature regimes due to harvesting were thought to be the prime factors responsible. Nitrogen cycling in the mature white spruce forest was typical of a steady-state system; cycling was very tight. Field estimates of mineralization for the forest floor (2.48 g/m('2)/yr) and the mineral soil (0.48 g/m('2)/yr) fit well into a schematic cycle developed around other estimates of N-pools and fluxes derived from the literature. This was also true of nitrification rates which were very low in both horizons. In the cleared areas, mineralization rates in the forest floor varied from 0.11 to 3.59 g/m('2)/yr and in the mineral horizon from 0.42 to 0.54 g/m('2)/yr. Nitrification rates varied from 1.49 to 3.01 g/m('2)/yr in the forest floor and from 0.24 to 0.27 g/m('2)/yr in the mineral soil. The effects of changes in abiotic and biotic controls on nitrogen mineralization and nitrification due to harvesting, and the implications of whole-tree vs. conventional logging are also discussed.
    Description
    Dissertation (Ph.D.) University of Alaska Fairbanks, 1986
    Date
    1986
    Type
    Dissertation
    Collections
    Older Theses Not Clearly Affiliated with a Current College
    Theses (Unassigned)

    entitlement

     
    ABOUT US|HELP|BROWSE|ADVANCED SEARCH

    The University of Alaska Fairbanks is an affirmative action/equal opportunity employer and educational institution and is a part of the University of Alaska system.

    ©UAF 2013 - 2023 | Questions? ua-scholarworks@alaska.edu | Last modified: September 25, 2019

    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.