Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 8 of 8 for “"shrub expansion"”.
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Drivers of landscape evolution in northern ecosystems: Shrub expansion, vegetation-fire interaction, and permafrost degradation
… climate and environmental change have been the expansion of tall shrubs, the degradation of permafrost, and the increase in frequency and severity of wildfires. These responses, however, are not mutually exclusive. For example, changes in hydrology due to the degradation of permafrost can alter …
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Shrub expansion in the low Arctic: The influence of snow and vegetation feedbacks on nitrogen cycling
Climate change has coincided with expansion of deciduous shrub species in the Arctic. Increased deciduous vegetation in the tundra could have profound implications on regional climate, carbon balance, and biogeochemical cycling of nutrients. Winter biological processes may be a mechanism explaining …
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Leveraging the Landsat Archive to Track Understory Evergreen Shrub Expansions in the Coweeta Basin, North Carolina
… suppression, has driven two common evergreen shrubs, rosebay rhododendron (Rhododendron maximum) and mountain laurel (Kalmia latifolia), to expand and proliferate in areas where they were once restricted. These two common shrubs are recognized agents of change in Appalachian forests because of …
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Spatiotemporal dynamics of carbon cycling and thermokarst in response to climate and fire-regime changes in the Arctic tundra biome
… after permafrost thaw), and (3) the patterns of shrub expansion in heterogenous tundra landscape in response to accelerated warming and fire disturbance. My results indicate that fire disturbance has threshold effects on tundra carbon stocks. Variation in fire return intervals from 5000 to 900 …
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Corticular Photosynthetic Dynamics for a Coastal Evergreen Shrub: Myrica Cerifera
… photosynthesis may be a mechanism to enhance shrub expansion due to increased whole plant carbon use efficiency (CUE) and water use efficiency (WUE) attributed to refixation.
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Integrating the effects of climate change and caribou herbivory on vegetation community structure in low Arctic tundra
… aboveground biomass, particularly in deciduous shrubs. This increased shrub density has the potential to dramatically alter the functioning of tundra ecosystems through its effects on permafrost degradation and nutrient cycling, and to cause positive feedbacks to global climate change through …
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Tracing carbon flows through Arctic and alpine watersheds
… sedge—and Betula nana—a competitive dwarf shrub—with glucose, and employed stable isotope tracing to quantify substrate conversion to CO2, incorporation in microbial biomass, and retention in bulk soil. We measured responses during peak biomass, fall senescence, and spring thaw to assess …
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Novel disturbance regimes in the Arctic: paleoecological perspectives on fire and thermo-erosion from Alaskan tundra
… enhancing surface roughness, and facilitating shrub expansion and snow drift, which can alter the soil thermal regime. Thus, these novel disturbance regimes may result in more rapid ecosystem changes in the Arctic compared to warming alone. However, the paucity of observational data from remote …