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Thirty-year Changes in Mineral Soil C in a Cumberland Plateau Forest as Influenced by Inorganic-N, Soil Texture, and TopographyKiser, Larry Christopher 09 January 2008 (has links)
Increases in atmospheric C have resulted in concerns about global warming and interest in finding means to sequester atmospheric C through land management strategies. The purpose of this study was to (i) compare changes in mineral soil C after a 30-year interval and (ii) examine the role of inorganic-N, soil texture, and topography in these changes. Soil samples were collected at permanently identified points on the Camp Branch Watershed, a second growth oak forest on the Cumberland Plateau in central Tennessee, in July of 1976 and archived. These points were re-sampled in July of 2006 and both archived and new samples of the 0 to 10 cm increment of the mineral soil were analyzed for C and N using the same procedures. Paired comparisons revealed changes in C and N were distinct to each of the 8 soil series. Comparison of 2006 samples to 1976 samples indicated changes in C concentration ranged from -13.1% to +12.0%. Changes in C mass ranged from -11.3% to +8.3%. Increases in C were most closely associated with increases in the C/total-N ratio. C was positively correlated to exchangeable inorganic-N in 1976 (r2 = 0.387) and 2006 (r2 = 0.107). Regression analysis revealed C increased with increasing azimuth and decreasing elevation in 1976 (r2 = 0.140). C was predicted only by clay content in 2006 (r2 = 0.079) and exhibited a negative relationship. Since topography was no longer a predictor of mineral soil C in 2006, we speculate that changes in forest cover also influenced changes in mineral soil C. / Master of Science
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Trophic structure of soil animal food webs of deciduous forests as analyzed by stable isotope labelingZieger, Sarah Lorain Janice 22 January 2016 (has links)
No description available.
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The effects of Amur honeysuckle (Lonicera maackii) and white-tailed deer (Odocoileus virginianus) on spider communities in a deciduous forestCunningham, Connor James 22 November 2021 (has links)
No description available.
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Soil litter and soil-dwelling invertebrate response to experimental removal of white-tailed deer (<i>Odocoileus virginianus</i>) and Amur honeysuckle (<i>Lonicera maackii</i>)Mahon, Michael B. 17 July 2019 (has links)
No description available.
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CARBON EXCHANGE IN A TEMPERATE DECIDUOUS FOREST IN SOUTHERN ONTARIOParsaud, Ananta R. 10 1900 (has links)
<p>Continuous measurements of carbon fluxes and meteorological variables were made at a newly initiated flux tower site at an oak-dominant temperate deciduous forest in Southern Ontario, Canada from January to December 2012. Results indicate this forest was a moderate carbon sink in 2012. Annual values of net ecosystem productivity (NEP), gross ecosystem productivity (GEP) and ecosystem respiration (R) were 263 ± 30, 1192 and 922 g C m<sup>-2</sup>, respectively. An unusual warm period in March caused a strong increase in R. Erratic peaks of daily air temperature in April also increased R. A drought in July and early August reduced NEP rates when soil moisture values reached the lowest point of the year in late July and early August (minimum 0.023 m<sup>3</sup> m<sup>-3</sup>). This decrease in NEP was mostly caused by a decrease in GEP, rather than increased R. Water use efficiency at this deciduous forest was 2.86 g C kg<sup>-1</sup> H<sub>2</sub>O, indicating conservative water use by the forest. Downwelling photosynthetic active radiation (PAR) was a dominant environmental control on photosynthesis, followed by air temperature and vapour pressure deficit, except in extreme dry periods when soil water stress affected carbon uptake. Extremely cloudy days in the growing season resulted in net carbon release due to low photosynthetic uptake values. Results indicate that large climatic fluctuations in this region may cause high instability in photosynthetic carbon uptake and release from soil carbon pools. This study helps to evaluate and quantify the responses of deciduous forests in the Great Lakes region to future climate change and extreme weather events.</p> / Master of Science (MSc)
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Vliv světla na složení a diverzitu lesní vegetace v Českém Středohoří / Influence of understory light on diversity and composition of forest vegetation in the České Středohoří Mts.Macek, Martin January 2011 (has links)
Light is essential component of forest ecosystem, as limited light availability in forest-floor restricts herb and tree seedlings growth. Importance of light availability for maintaining plant species diversity and community structure wasn't sufficiently evaluated in the Czech Republic. This study focus on the ecological relevance of light availability on both landscape and local scale. Relationship of light to cover, diversity and species composition was quantified in the thesis. Dominant tree species affected light availability and its spatial variability. Light availability was along the soil reaction and slope most influential factor for large-scale species diversity. Within-site light variability affected plant diversity more than soil reaction variability. Measuring light by means of hemispherical photography seems to be an appropriate for studies like this. Light availability influnence on community compostition is weak in comparison with other environmental gradients.
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