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Physical Sciences and Mathematics Commons

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Environmental Sciences

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Natural Resources Management and Environmental Sciences

1998

Articles 1 - 4 of 4

Full-Text Articles in Physical Sciences and Mathematics

Stand Density Effects On Biomass Allocation Patterns And Subsequent Soil Nitrogen Demand, Christopher Dicus, Thomas J. Dean Jan 1998

Stand Density Effects On Biomass Allocation Patterns And Subsequent Soil Nitrogen Demand, Christopher Dicus, Thomas J. Dean

Natural Resources Management and Environmental Sciences

Growth and yield data from a loblolly pine plantation in southeastern Louisiana were obtained yearly from 1993 to 1996 on numbered trees within two stands initially planted on a 1.22- by 1.22-meter spacing, and two stands planted on a 2.44- by 2.44-meter spacing. Using allometric equations derived from a 1994 on-site destructive harvest, cited nitrogen concentrations of various tree tissues, and accounting for foliar nitrogen retranslocation, stand growth and soil nitrogen demands were determined. Results showed that production of all aboveground tissues increased as stand density index (SDI) increased. Annual soil nitrogen demand increased with SDI primarily as a result …


Postfire Succession And Disturbance Interactions On An Intermountain Subalpine Spruce-Fir Forest, Michael J. Jenkins, Christopher Dicus, Elizabeth G. Hebertson Jan 1998

Postfire Succession And Disturbance Interactions On An Intermountain Subalpine Spruce-Fir Forest, Michael J. Jenkins, Christopher Dicus, Elizabeth G. Hebertson

Natural Resources Management and Environmental Sciences

Four general postfire successional pathways leading to a climax Engelmann spruce (Picea engelmmlilii Parry)-subalpine fir (Abies /asiocarpa [Hook] Nutt.) forest operate on the T.W. Daniel Experimental Forest in northern Utah. Depending on the successional pathway followed. reestablishment of the prefire climax forest will take 200 to 400 years or more due to a rarity of extreme burning conditions. During the long period between catastrophic stand-replacing fires, a variety of other natural disturbances contribute to the varying structure and composition of vegetation and the fuel mosaic in internountain subalpine spruce-fir forests. Disturbances may range from chronic and small scale …


Restoration Of Mixed Conifer Communities Using Prescribed Fire In Bryce Canyon National Park, Michael J. Jenkins, Christopher Dicus, Joel E. Godfrey Jan 1998

Restoration Of Mixed Conifer Communities Using Prescribed Fire In Bryce Canyon National Park, Michael J. Jenkins, Christopher Dicus, Joel E. Godfrey

Natural Resources Management and Environmental Sciences

A fire history conducted in the mixed conifer community types of Bryce Canyon National Park found the mean fire-return interval has lengthened from 7.5 to 45 years since 1900. Dendroecology, species, diameter, and age-class analysis showed a change in stand composition in favor of white fir (Abies concolor) and Douglas-fir (Psuedotsuga menziesii) and a 200% increase in fuel accumulation. Recommendations for prescribed burning and mechanical reduction of fuels were incorporated into the Bryce Canyon management plan.


Biological And Management Implications Of Fire-Pathogen Interactions In The Giant Sequoia Ecosystem, Douglas D. Piirto, John R. Parmeter Jr., Fields W. Cobb Jr., Kevin L. Piper, Amy C. Workinger, William J. Otrosina Jan 1998

Biological And Management Implications Of Fire-Pathogen Interactions In The Giant Sequoia Ecosystem, Douglas D. Piirto, John R. Parmeter Jr., Fields W. Cobb Jr., Kevin L. Piper, Amy C. Workinger, William J. Otrosina

Natural Resources Management and Environmental Sciences

An overriding management goal for national parks is the maintenance or, where necessary, the restoration of natural ecological processes. In Sequoia-Kings Canyon and Yosemite National Parks, there is concern about the effects of fire suppression on the giant sequoia-mixed conifer forest ecosystem. The National Park Service is currently using prescribed fire management and prescribed burning as tools to reintroduce fire as a natural process. However, there are questions about the positive and negative effects of reintroducing fire in the giant sequoia-mixed conifer ecosystem. Reintroducing fire in the Sierra Nevada forests needs critical evaluation with respect to the pathogens that affect …