Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Life Sciences

Disturbances In North American Boreal Forest And Arctic Tundra: Impacts, Interactions, And Responses, Adrianna C. Foster, Jonathan A. Wang, Gerald V. Frost, Scott J. Davidson, Elizabeth Hoy, Kevin W. Turner, Oliver Sonnentag, Howard Epstein, Logan T. Berner, Amanda H. Armstrong, Mary Kang, Brendan M. Rogers, Elizabeth Campbell, Kimberley R. Miner, Kathleen M. Orndahl, Laura Bourgeau-Chavez, David A. Lutz, Nancy H. F. French, Dong Chen, Jinyang Du, Tatiana A. Shestakova, Jacquelyn K. Shuman, Ken Tape, Anna Maria Virkkala, Christopher Potter, Scott Goetz Oct 2022

Disturbances In North American Boreal Forest And Arctic Tundra: Impacts, Interactions, And Responses, Adrianna C. Foster, Jonathan A. Wang, Gerald V. Frost, Scott J. Davidson, Elizabeth Hoy, Kevin W. Turner, Oliver Sonnentag, Howard Epstein, Logan T. Berner, Amanda H. Armstrong, Mary Kang, Brendan M. Rogers, Elizabeth Campbell, Kimberley R. Miner, Kathleen M. Orndahl, Laura Bourgeau-Chavez, David A. Lutz, Nancy H. F. French, Dong Chen, Jinyang Du, Tatiana A. Shestakova, Jacquelyn K. Shuman, Ken Tape, Anna Maria Virkkala, Christopher Potter, Scott Goetz

Michigan Tech Publications

Ecosystems in the North American Arctic-Boreal Zone (ABZ) experience a diverse set of disturbances associated with wildfire, permafrost dynamics, geomorphic processes, insect outbreaks and pathogens, extreme weather events, and human activity. Climate warming in the ABZ is occurring at over twice the rate of the global average, and as a result the extent, frequency, and severity of these disturbances are increasing rapidly. Disturbances in the ABZ span a wide gradient of spatiotemporal scales and have varying impacts on ecosystem properties and function. However, many ABZ disturbances are relatively understudied and have different sensitivities to climate and trajectories of recovery, resulting …


Understanding The Role Of Small Mammals In Arctic Biogeochemical Cycling, Austin Roy May 2022

Understanding The Role Of Small Mammals In Arctic Biogeochemical Cycling, Austin Roy

Open Access Theses & Dissertations

Small mammals play an integral role in their ecosystems. This is especially true in northern ecosystems, where small mammals represent both top-down and bottom-up forces and can have strong effects on ecosystem function through affecting biogeochemical cycling. Despite these important effects, the role of small mammals in influencing biogeochemical cycling has been largely underappreciated in the understanding of arctic ecosystems, leading to a call to better understand how small mammal herbivores impact ecosystem processes including carbon cycling. The overarching goal of this dissertation is to assess how biogeochemical cycling is affected by small mammal herbivore presence, behavior, and population dynamics …


The Comparative Effects Of Short Duration, High Density And Conventional, Rotational Grazing On Different Soil, Vegetation And Animal Parameters In Dry And Mesic Grasslands Of South Africa, Jamie Paulse, Paul Malan, Nico Smit Mar 2022

The Comparative Effects Of Short Duration, High Density And Conventional, Rotational Grazing On Different Soil, Vegetation And Animal Parameters In Dry And Mesic Grasslands Of South Africa, Jamie Paulse, Paul Malan, Nico Smit

IGC Proceedings (1997-2023)

Short duration, high density grazing is a grazing management strategy that incorporates the rotation of large livestock herds, often at double or triple the normal prescribed stocking densities of the specific area. It is claimed that this type of grazing management can improve rangeland health by improving soil and vegetation condition, and subsequently influencing animal performance. Regardless of the scarcity of scientific evidence validating these claims, the change from conventional rotational grazing systems to short duration, high density grazing systems is on the increase in South Africa. This study aims to assess these claims, through the quantification of various rangeland …


Characterization Of Site-Specific Vegetation Activity In Alaskan Wet And Dry Tundra As Related To Climate And Soil State, Michael Gregory Brown, Kyle C. Mcdonald, Reiner Zimmermann, Nicholas Steiner, Stephanie Devries, Laura Bourgeau-Chavez Feb 2022

Characterization Of Site-Specific Vegetation Activity In Alaskan Wet And Dry Tundra As Related To Climate And Soil State, Michael Gregory Brown, Kyle C. Mcdonald, Reiner Zimmermann, Nicholas Steiner, Stephanie Devries, Laura Bourgeau-Chavez

Michigan Tech Publications

We present discrete (2-h resolution) multi-year (2008–2017) in situ measurements of seasonal vegetation growth and soil biophysical properties from two sites on Alaska's North Slope, USA, representing dry and wet sedge tundra. We examine measurements of vertical active soil layer temperature and soil moisture profiles (freeze/thaw status), woody shrub vegetation physiological activity, and meteorological site data to assess interrelationships within (and between) these two study sites. Vegetation phenophases (cold de-hardening start, physiological function start, stem growth start, stem growth end, physiological function end, cold hardening completion) were found to have greater interannual day of year (DOY) occurrence variability at the …