Life Sciences Commons^™

Modeling Yield And Aboveground Live Tree Carbon Dynamics In Oak-Gum-Cypress Bottomland Hardwood Forests, Suchana Aryal

Theses and Dissertations

The importance of bottomland hardwood (BLH) forests to support the economy through timber production and carbon sequestration is acknowledged; however, their full potential is yet to be explored. This study developed variable density yield models for BLH oak-gum-cypress forests along the US Gulf Coast and Lower Mississippi River Delta. The models, with an adjusted R2 of 98% for cubic foot growing stock volume and 77% for Doyle board foot sawlog volume, are expected to be valuable tools for landowners and managers seeking to make informed decisions about BLH forest management.

A carbon stock model was also developed, and carbon sequestration …

Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona

USDA Wildlife Services: Staff Publications

Climate change and disturbance make it difficult to project long-term patterns of carbon sequestration in tropical forests, but large ecosystem experiments in these forests can inform predictions. The Canopy Trimming Experiment (CTE) manipulates two key components of hurricane disturbance, canopy openness and detritus deposition, in a tropical forest in Puerto Rico. We documented how the CTE and a real hurricane affected tree recruitment, biomass, and aboveground carbon storage over 15 years. In the CTE treatments, we trimmed branches, but we did not fell trees. We expected that during the 14-year period after initial canopy trimming, regrowth of branches and stems …

Modeling Fire Observations, Ignition Sources, And Novel Fuels To Understand Human Impacts On Fire Regimes Across The U.S., Emily Fusco

Doctoral Dissertations

Fire is a natural, and necessary, component of many ecosystems. However, people are changing the spatial and temporal distribution of wildfires in the U.S. at great economic and ecological costs. My dissertation addresses the impacts of humans on U.S. fires both through the introduction of ignition sources and flammable grasses. Further, I evaluate fire datasets that are widely used to investigate these phenomena over large spatial and temporal scales. Finally, I create an aboveground carbon map that can be used to estimate the potential carbon loss consequences in western U.S. ecosystems most at risk to fire. My work shows that …

Individual Tree And Stand-Level Carbon And Nutrient Contents Across One Rotation Of Loblolly Pine Plantations On A Reclaimed Surface Mine, Hannah Z. Angel, Jeremy S. Priest, Jeremy P. Stovall, Brian P. Oswald, Hans M. Williams

Faculty Publications

While reclaimed loblolly pine (Pinus taeda L.) plantations in east Texas, USA have demonstrated similar aboveground productivity levels relative to unmined forests, there is interest in assessing carbon (C) and nutrients in aboveground components of reclaimed trees. Numerous studies have previously documented aboveground biomass, C, and nutrient contents in loblolly pine plantations; however, similar data have not been collected on mined lands. We investigated C, N, P, K, Ca, and Mg aboveground contents for first-rotation loblolly pine growing on reclaimed mined lands in the Gulf Coastal Plain over a 32-year chronosequence and correlated elemental rates to stand age, stem …

Dynamics Of Postfire Aboveground Carbon In A Chronosequence Of Chinese Boreal Larch Forests, Yuan Z. Yang, Wen H. Cai, Jian Yang, Megan White, John M. Lhotka

Forestry and Natural Resources Faculty Publications

Boreal forests store a large proportion of the global terrestrial carbon (C), while wildfire plays a crucial role in determining their C storage and dynamics. The aboveground C (AC) pool is an important component of forest C stocks. To quantify the turning point (transforming from C source to C sink) and recovery time of postfire AC, and assess how stand density affects the AC, 175 plots from eight stand age classes were surveyed as a chronosequence in the Great Xing'an Mountains of Northeast China. Linear and nonlinear regression analyses were conducted to describe postfire AC recovery patterns. The results showed …

Factors Contributing To Carbon Fluxes From Bioenergy Harvests In The U.S. Northeast: An Analysis Using Field Data, Anna M. Mika, William S. Keeton

Rubenstein School of Environment and Natural Resources Faculty Publications

With growing interest in wood bioenergy there is uncertainty over greenhouse gas emissions associated with offsetting fossil fuels. Although quantifying postharvest carbon (C) fluxes will require accurate data, relatively few studies have evaluated these using field data from actual bioenergy harvests. We assessed C reductions and net fluxes immediately postharvest from whole-tree harvests (WTH), bioenergy harvests without WTH, and nonbioenergy harvests at 35 sites across the northeastern United States. We compared the aboveground forest C in harvested with paired unharvested sites, and analyzed the C transferred to wood products and C emissions from energy generation from harvested sites, including indirect …